429 Too Many Requests

Mõned ettevõtted kasutavad enda toodete parendamiseks ja uute toodete turule toomiseks peamiselt teiste ettevõtete arendatud tehnoloogiaid. Leidub aga ka ettevõtteid, mis viivad põhiuuringuid ise läbi ja arendavad tehnoloogiaid ettevõttesiseselt. Kas see lähenemise erinevus peaks olema oluline neile, kes kasutavad lõpptoodet igapäevaselt enda hambaravipraksises või -laboris? Jah, kuna need ettevõtted, millel on sügav arusaam tehnoloogia aluseks olevatest materjalidest, keemiast ja tehnikatest, on suutelised lahendama olemasolevaid ja tekkivaid probleeme ning reageerima turu vajadustele paindlikult ja kiiresti. See artikkel kirjeldab mitme Kuraray Noritake Dental Inc.-i välja töötatud tehnoloogia mõju indirektsete restauratsioonide tsementimisele.

Adhesiivse tsementimise ajalugu ja tänapäev

Erinevat tüüpi keraamikatest hambarestauratsioonide freesimise võimalus on avanud hambaproteetikas uusi horisonte: võimalik on luua ja paigaldada väga esteetilisi restauratsioone. Tihti alahinnatakse selles kontekstis adhesiivsete tsementsüsteemide, mis ainult ei toeta läbipaistvate hambavärvi restauratsioonide esteetilist väljanägemist, vaid võimaldavad ka vähem invasiivset preparatsiooni ja restauratsiooni mudeleid. Varased süsteemid, millega loodi hammaste ja indirektsete restauratsioonide vahel keemiline adhesioon, ei taganud pikaajalist toimivust ja olid väga tundlikud tehnika suhtes ning ühtlasi oli pealekandmise protseduur väga keerukas. Kuraray Noritake Dental Inc.-i tootearendus soodustas oluliselt süsteemide pikaajalist toimivust ja lihtsustas käsitsemist.

Pikaajalise sidususe optimeerimine

Selleks, et varajased tsementimissüsteemid kinnituks pikaajaliselt hambastruktuuridele (eriti dentiinile), otsustas Kuraray (Kuraray Noritake emaettevõte) 1970ndatel keskenduda võimsama adhesiivse monomeeri arendamisele. Selle eduka teekonna esimene samm oli fosfaatmonomeeri fenüül-P loomine 1976. aastal. Viis aastat hiljem viisid pidevad jõupingutused parandada selle molekulaarstruktuuri populaarse MDP-monomeeri loomiseni, millega suudeti luua eriti tugev ja pikaajaline side emailiga, dentiiniga, metalliga ja tsirkooniumiga.

Asjaolu, et see aine on endiselt igas Kuraray Noritake Dental Inc.-i adhesiivis ja adhesiivses tsementimissüsteemis, ja ka kasutusel teiste tootjate toodetes, et optimeerida sidustugevust ja kinnituse kestvust, on märk selle leiutise geniaalsusest. Võrreldes mujal sünteesitud MDP-ga paistab Kuraray Noritake Dental Inc.-i originaalne MDP-monomeer silma oma ületamatu puhtuse poolest. Sõltumatud uuringud näitavad, et sellel puhtuse tasemel on kinnitumise toimivusnäitajatele positiivne mõju.1 Säilitades toimivusnäitajate stabiilsuse ka niiskes keskkonnas, on MDP-monomeer muutnud ka seda sisaldavate toodete toimivuse stabiilsemaks.

Erinevatel MDP-monomeeridel on erinev puhtuse aste ja sidumisvõime.

Ette valmistati kolm eksperimentaalset isesöövituvat praimerit, mis koosnesid 15 massiprotsendi osas 10-MDP-st, mis pärinesid eri allikatest: KN (Kuraray Noritake Dental), PCM (Saksamaa) või DMI (Designer Molecules Inc., USA). Andmed pärinevad dr Kumiko Yoshiharalt.

Ainuüksi adhesiivse monomeeri sisaldusest aga ei piisa, et adhesiivsed vaiktsemendisüsteemid saaksid luua tugeva sideme ja ääresulu. Vaja on ka see monomeer tõhusalt polümeriseerida. Seda ei ole samas alati lihtne saavutada. PANAVIA™ V5 tõhusaks valgusja nakkekõvastamiseks lõi Kuraray Noritake Dental Inc. Touch-Cure tehnoloogia. Selle tehnoloogia olulisem osa on praimeris PANAVIA™ V5 Tooth Primer sisalduvja äsja välja töötatud väga aktiivne polümerisatsiooni katalüsaator, mille omadused ei kao happelise MDPga kokkupuutel. See soodustab polümerisatsiooni algamist hamba ja tsemendi liitekohas niipea, kui pastat PANAVIA™ V5 Paste lisatakse juba praimeriga töödeldud hambapinnale. Valguskõvastuvas vaiktsemendisüsteemis PANAVIA™ Veneer LC, mida kasutatakse samade praimeritega, on praimeris PANAVIA™ V5 Tooth Primer sisalduva polümerisatsiooni katalüsaatori toimemehhanism sama. See soodustab adhesiivi liitekoha polümerisatsiooni, samal ajal kui valguskõvastatav PANAVIA™ Veneer LC Paste säilitab stabiilsuse ümbritseva valguse suhtes.

Seda fenomeni hinnati näiteks PANAVIA™ V5 eelkäija PANAVIA™ F2.0 puhul. Uuringu tulemus: PANAVIA™ F2.0-l oli palju paremad äärte sulgemise omadused kui teistel hinnatud tsemendisüsteemidel.2 See liitekoha dokumenteeritud sulgemisvõime vähendab servade lekkimise esinemissagedust, suurendab polümerisatsiooni suhet isegi isekõvastuvas režiimis (valguskõvastumiseta või kui restauratiivmaterjal blokeerib valguset) ja toob kaasa eriti tugeva sideme.

Polümerisatsiooni katalüsaatori täiendav eelis on see, et see on tugev redutseerija. See neutraliseerib naatriumhüpokloriti, mida kasutatakse enamasti endodontilise ravi ajal loputuslahusena, ja eemaldab seeläbi pärast seda peale kantud tsemendipasta sidustugevusele avalduvad negatiivsed mõjud.

Lihtsustame klaaskeraamilist tsementimist

Vähem pudeleid ja protseduurietappe ning sujuvam tsementimine: selle pärast isesidustuvad vaiktsemendid 2000ndate alguses välja töötati ja turule toodigi. Enamikel neist toodetest on aga piiratud kasutusnäidustuste ulatus. Need töötavad hästi tsirkooniumil, emailil ja dentiinil, kuid neid ei soovitata kasutata või vajavad täiendava silaanpraimeri kasutamist klaaskeraamika puhul. MDP-d sisaldav PANAVIA™ SA Cement Universal erineb selle poolest, et sisaldab veel üht Kuraray Noritake Dental Inc.-i patenteeritud tehnoloogiat: pika süsinikuahelaga silaanist sidusainet LCSi Monomer. See monomeer moodustab tugeva keemilise sideme vaikkomposiidiga, portselaniga ja ränidioksiidi tüüpi keraamikatega (nt liitiumdisilikaat), mistõttu ei ole eraldi silaanikomponenti (praimerit või adhesiivi) vaja. Selle tehnoloogia eeliseid ära kasutades eristab PANAVIA™ SA Cement Universal end selgelt teistest isenakkuvatest vaiktsementidest kui ühekomponentne tsemendisüsteem, mida saab kasutada isegi klaaskeraamikast restauratsioonidel.

Vajadusel saab suurendada toote sidustugevust hambastruktuuriga, kasutades Rapid Bond tehnoloogiat hõlmavat populaarset universaalset adhesiivi CLEARFIL™ Universal Bond Quick. Kuraray Noritake Dental Inc. töötas selle tehnoloogia välja, et lahendada universaalsete adhesiivide puhul levinud hambastruktuuri (eriti dentiini) aeglase läbitungimisega seotud probleeme. Hea läbitungimise saavutamiseks tuleb neid adhesiive hambastruktuuri pikalt hõõruda, sest vastasel korral peavad kasutajad ootama pikalt, enne kui kihti valguskõvastada saavad. Koosnedes originaalsest MDP-monomeerist ja hüdrofiilsetest amiidmonomeeridest, võimaldab Rapid Bond tehnoloogiat suurt afiinsust veega, tungides seeläbi kiirelt märja dentiini sügavatesse kihtidesse. Selle tõttu on aplitseerimisaeg lühem ja käsitsemine lihtsam, ilma et sidumisvõime väheneks.

Järeldus

Kuraray Noritake Dental Inc.-i välja töötatud tehnoloogiad on kõvasti suurendanud adhesiivsete tsemendisüsteemide sidusustugevust ja isesidustuvate vaiktsementide kasutusnäidustuste ulatust. Seetõttu suudab ettevõtte pakkuda vaiktsemente igale kasutajale kõikide tavapäraste kliiniliste olukordade puhul. Väiksem arv komponente ja vähem protseduuri etappe väldivad vigade tekkimist ja suurendavad restauratsioonide esteetikat ja püsivust. Lisaks tehnoloogiaga seotud kasuteguritele on mainitud toodetel veel nii mõndagi muud pakkuda. Täpse kirjelduse leiab veebist aadressil kuraraynoritake.eu.   

Viited

*) Functional monomer impurity affects adhesive performance.; Yoshihara K, Nagaoka N, Okihara T, Kuroboshi M, Hayakawa S, Maruo Y, Nishigawa G, De Munck J,
Yoshida Y, Van Meerbeek B. Dent Mater. 2015 Dec;31(12):1493-501.
**) Touch-Cure Polymerization at the Composite Cement-Dentin Interface.; Yoshihara K, Nagaoka N, Benino Y, Nakamura A, Hara T, Maruo Y, Yoshida Y, Van Meerbeek
B.J Dent Res. 2021 Aug;100(9):935-94

Mõned ettevõtted kasutavad enda toodete parendamiseks ja uute toodete turule toomiseks peamiselt teiste ettevõtete arendatud tehnoloogiaid. Leidub aga ka ettevõtteid, mis viivad põhiuuringuid ise läbi ja arendavad tehnoloogiaid ettevõttesiseselt. Kas see lähenemise erinevus peaks olema oluline neile, kes kasutavad lõpptoodet igapäevaselt enda hambaravipraksises või -laboris? Jah, sest kõik nullist välja töötavatel ettevõtetel on enamasti sügavam arusaam toodetest ja nende tootmisprotseduuridest, mis teeb lihtsamaks muuta spetsiifilisi omadusi, lahendada probleeme ja reageerida turu vajadustele. See artikkel kirjeldab mitme Kuraray Noritake Dental Inc.-i välja töötatud tehnoloogia mõju indirektsete restauratsioonide valmistamise töövoole.

DIREKTSED RESTAURATSIOONID – KEERULISEST LIHTSAKS

Hambaadhesiive ja vaikkomposiite kasutav adhesiivne restauratiivne hambaravi on kõige populaarsem viis ravimaks karioossete kolletega hambaid. Tänapäeval piisab enamasti ühest universaalse adhesiivi pudelist ja universaalse komposiidi ühest või kahest värvitoonist ja opaaksusest, et luua kestvaid tulemusi, st kui valitud on õiged materjalid. See ei pruugi alati nii olla. Direktsete restauratsioonide valmistamise tehnikad on pikalt olnud üsna keerulised: adhesiivid olid tehnikatundlikud mitme pudeli ja etapiga süsteemid ja neil oli pikk pealekandmise aeg. Komposiidist täitematerjalidega saab elutruusid tulemusi aga vaid mitme erineva värvitooni ja opaaksuse õigel viisil kombineerimisel. Isegi kui need komplekssed protseduurid õigel viisil läbi viia, on mikrolekke, värvimuutuse ja lõpuks ka teisese kaariese risk võrdlemisi suur. Kuraray Noritake Dental Inc. hakkas nendele probleemidele üsna varakult tähelepanu pöörama, alustades 1981. aastal välja töötatud MDP-monomeeri kasutusele võtmisega.

SIDUSUSTUGEVUSE OPTIMEERIMINE

Originaalne MDP-monomeer lahendas adhesiivsüsteemide pikaajalise toimivuse piirangutega seotud küsimusi. MDP hüdrofiilne (fosfaadi-) rühm moodustab emaili ja dentiini alusaines hüdroksüapatiidis leiduva kaltsiumiga
eriti tugeva ja kauakestva keemilise sideme. Tekkinud MDP-Ca sool moodustab põhja stabiilsele, tugevale ja kestvale hübriidkihile. Koostoimes sidusaines sisalduva vaiguga tekib kaviteedile pärast valguskõvastamist
tihke täide. MDP on tänaseni oluline osa kõigist Kuraray Noritake Dental Inc.-i adhesiividest ja on peamine põhjus, mis tegi sidusainest CLEARFIL™ SE Bond isesöövitavate adhesiivide kullastandardi.

Veendunud, et hambaadhesiivid peaksid olema võimelised rohkemaks kui kestvaks sidemeks, hakkas Kuraray Noritake Dental Inc. keskenduma teise probleemi lahendamisele: kaviteeti jäänud bakterite põhjustatud demineralisatsioonile ja kavitatsioonile. Teiste adhesiivsete monomeeride arendamise kogemusele toetudes leiutas Kuraray Noritake Dental Inc. MDPB-monomeeri, millel on antibakteriaalne kaviteeti puhastav toime. Erinedes antibakteriaalsetest ainetest, mis võivad vähendada järgmistes etappides aplitseeritud adhesiivi sidustugevust, tapab MDPB-monomeer allesjäänud bakterid sidustugevust mõjutamata. See sisaldub kahepudelise isesöövitava adhesiivi CLEARFIL™ SE Protect praimeris ja immobiliseerub polümerisatsiooni toimel.

MDPB bakteritsiidne mehhanism on eeldatavast sarnane tuntud antibakteriaalsele ainele CPC (tsetüülpüridiinkloriid), mida leidub paljudes hambapastades ja loputusvedelikes. 

Kuigi kahepudelilised isesöövitavad adhesiivid on juba lihtsustanud adhesiivi kasutamise protseduuri, lähevad ühepudelilised universaalsed adhesiivid veel kaugemale. Tuua kokku mitmeetapiliste süsteemide erinevad komponendid ühte pudelisse vähendamata seejuures toote stabiilsust, on paras väljakutse. Tänase tehnoloogiaga on see saanud võimalikuks. Pinna sulgemiseks esimesel võimalusel pärast aplitseerimist peab monomeeride läbitungimine hambakoesse olema kiire ja tõhus. Läbitungimist aeglustavad aga enamasti monomeerid, millel kulub hambastruktuuri – eriti märja dentiini – läbimiseks kauem, ja vahel tuleb neid isegi selle sisse hõõruda. See on ka põhjus, miks Kuraray Noritake Dental Inc. keskendus Rapid Bond tehnoloogia arendamisele. See sisaldab originaalset MDP-monomeeri ja hiljuti välja töötatud hüdrofiilseid ristseonduvaid amiidimonomeere ning on integreeritud sidusainesse CLEARFIL™ Universal Bond Quick. Hüdrofiilsed amiidimonomeerid tagavad kiire, sügava ja täieliku läbitungimise dentiini ja
moodustavad kõvastumisel tihedalt ristseondunud polümeeri võrgustiku ja seega tugeva ja kestva sideme. Seeläbi kaob vajadus ootamise ja hõõrumise järele ning kaviteet sulgub valguskõvastamisel tihkelt ja kestvalt.

Hüdrofiilsuse (afiinsus vee suhtes) tõttu tungivad Rapid Bond tehnoloogia amiidimonomeerid hästi dentiinist läbi. Pärast valguskõvastumist ei ima side enam vett ja peab seetõttu kaua vastu.

DIREKTSETE RESTAURATIIVIDE OPTIMEERIMINE

Mitme kihi, värvitooni ja opaaksuse kombineerimine Õnneks ei ole enam paljude kliiniliste juhtumite puhul vaja kasutada keerukaid kihistamistehnikaid, et luua elutruusid komposiitrestauratsioone. Selle põhjuseks on uudsed vaikkomposiidid, mis sulanduvad märkamatult kokku kõrvalhamba struktuuriga. Seda omadust võimaldas Kuraray Noritake Dental Inc.-i välja töötatud Light Diffusion Technology (LDT). See tehnoloogiat kätkevad spetsiaalsed eelpolümeriseeritud täiteained, mis toimivad miljonite mikroprismadena, mis edastavad ja painutavad ümbritsevalt hambastruktuurilt pärit valgust. Matriitsi suhtes optimeeritud suuruse, hajuvuse ja murdumisnäitajaga täiteaine sulab kõrvalhammastega eristamatult kokku. Kogu CLEARFIL MAJESTY™ komposiidiseeria sisaldab seda patenteeritud täiteainetehnoloogiat. Kuraray Noritake Dental Inc.-i kõige viimasem toode CLEARFIL MAJESTY™ ES-2 Universal, milles on kasutusel LDT, on kasutatav ainult ühe värvitooniga: kaks tooni esihammastele ja üks tagahammastele. See sulandub nii hästi kokku, et katab põhimõtteliselt kogu VITA A1-D4 värvispektri.

Valgusmurdumine ja -hajuvus tagavad hea optilise kattuvuse: CLEARFIL MAJESTY™ ES-2 valgust hajutavad täiteained Kuraray Noritake Dental Inc.-lt.

Hea väljanägemine ei sõltu alati sulandumisest ümbritsevaga ja restauratsiooni märkamatutest servadest, mistõttu arendas Kuraray Noritake välja täiteained, mis hoolitsevad ka ülejäänu eest: loomulik pinnaläige ja poleerimise kestvus. Kolme voolavuse astmega CLEARFIL MAJESTY™ ES Flow sisaldab Submicron Filler tehnoloogiat, mis koosneb läikivatest mikronist väiksematest täiteosakestest. Need täiteosakesed on nii väikesed, et valgus peegeldub loomulik viisil isegi pärast kulumist. Miljonite nende imepisikeste täiteosakeste ühendamiseks ja koos hoidmiseks kasutatakse Kuraray Noritake Dental Inc.-i erakordset silaanitehnoloogiat. See võimaldab kasutada suuremaid täiteaine koguseid vähese viskoossusega komposiitides ja piirab veeimavust, mis tooks kaasa kõvastunud komposiidi lagunemise. Mikronist väikesemate läikivate täiteosakeste, valgust hajuvate täiteainete, vaikmatriitsi ja silaanitehnoloogia vaheline tasakaal on võtmetähtsusega mehaaniliste ja optiliste omaduste optimeerimisel.

Näide ühetoonilisest restauratsioonist CLEARFIL MAJESTY™ ES-2 Universaliga.

JÄRELDUS

Adhesiivsed monomeerid, täiteosakeste ja silaanitehnoloogiad pakuvad tugeva täiteainete, klastrite ja vaigumatriitsidevaliku: Kuraray Noritake Dental Inc. on ilmselgelt usaldusväärne partner adhesiivsete restauratsioonide valdkonnas.Viimaste aastakümnete jooksul välja töötatud patenteeritud tehnoloogiad aitavad kaasa direktsete restauratsioonide (pikaajalisele) toimele ja võimaldavad lihtsamalt saavutada töökindlaid ja esteetilisi tulemusi.

Interview with Andreas Chatzimpatzakis

Fewer bakes, fewer ceramic powders - there is clearly a trend toward simplification in the production of zirconia-based prosthetic work. This is also true for implant-based restorations, which often involve gum parts. DT Andreas Chatzimpatzakis, international trainer for Kuraray Noritake Dental Inc., and the owner of ACH Dental Laboratory in Athens, Greece, shares his approach to high aesthetics in implant prosthodontics in the following conversation.

You are a user of the CERABIEN™ ZR portfolio from the outset. When did you test the products for the first time and why?

Well, it was many years ago when I finished my very first zirconia-based restoration. The reason to test CERABIEN™ ZR was that when I asked the dental technician who had milled the framework which porcelain system to use. He suggested to use CERABIEN™ ZR, which I did. I was immediately impressed by the system and by the outcome I was able to achieve on the first attempt.

Did you ever test any other porcelain systems for ceramic layering?

Yes. Before I becoming an international trainer for Kuraray Noritake Dental Inc., I had the opportunity to test many other porcelain systems for layering on zirconia. Based on this experience, I can say that CERABIEN™ ZR is unique and the best system I have ever used. The reason is that its translucency and chroma are extremely close to natural teeth. In addition, due to a controlled firing shrinkage, a One-Bake Technique may be employed even in long-span restorations.

Your hands-on demonstration at the Kuraray Noritake Dental booth during the IDS 2023 in Cologne focused on White and Pink Aesthetics achieved with CERABIEN™ ZR. Is there a specific concept you use?

Nowadays, everyone producing dental restorations – no matter whether based on natural teeth or on implants – is confronted with increasing aesthetic demands of patients and dental practitioners. The high demands are developed because life-like restorations and cosmetic dental treatment outcomes are presented everywhere in the web and on social media. The showcased quality of outcomes is simply expected, even if the financial budget is limited. To be able to fulfil these demands in the field of implant-based prosthodontics, I have developed an approach that allows me to achieve high aesthetics with little effort. My concept is based on using not too many ceramic powders. For extra chroma and special characterization, I rely on the power of the internal live stain technique, first introduced by Hitoshi Aoshima-sensei.

Please summarize the most important details of your presentation.

The first important detail is the design and characterization of the framework. Before sintering, I apply Esthetic Colorant for KATANA™ Zirconia. After the sintering process, shade base stain and internal stains are mixed and applied. In this way, I create a nice canvas that helps me to achieve a life-like result with only a few selected ceramic powders. In most cases, three to five powders are enough to produce a great result. Among the powders used most frequently are Opacious Body, Body, LTX, Mamelon and CCV. After the first bake and a little grinding, I make use of internal stains again. They offer support in the controlling of the chroma and the integration of special characteristics. When this step is completed, the final build-up is done with one or two ceramic powders, most of the times LT1 and Enamel or LT0. Pink aesthetics are usually created with Tissue 1, 3 and 5. For the free gingiva, LT Coral is my go-to solution. The major goal is always to obtain maximum quality in a minimum of time. To achieve this, a good knowledge of the materials and of course practicing – on both, porcelain build-up and morphology – are strictly required.

Fig. 1. Complex implant-based restoration: Framework design.

Fig. 2. Esthetic Colorant …

Fig. 3.  … applied prior to the final sintering procedure.

Fig. 4. Appearance after sintering.

Fig. 5. Final outcome.

Are there any concrete tips and tricks you would like to share?

For the characterization of the framework, I mix the internal stains with shade base stain powders; mostly with SS Fluoro. For the first bake, especially when the restoration is large and the amount of ceramic to be applied huge, I reduce the heating rate up to 38 degrees per minute. I also increase the drying process up to 17 or even 20 minutes depending to the restoration. Experience shows that these measures optimize the aesthetic outcomes.

You often mention that it is extraordinarily important to understand the morphology of natural teeth to be able to produce beautiful restorations. Why is this the case?

A successful prosthetic restoration needs to offer proper function and aesthetics. Function means a precise fit, perfect contact points and occlusion, a proper emergence profile and interproximal embrasures for self-cleaning etc. All this is described by the term morphology. Aesthetics, on the other hand, is guided by shape and colour. The effort required to establish a proper morphology is much higher (about 70 percent of the total work) than the effort involved in obtaining the right translucency, opalescence and chroma.

What instruments do you use to imitate the morphology of natural teeth and how do you do it?

I usually make use of the Optimum™ Spring Ceramic Brush Size 8 (MPF Brush Co.), stones and diamond burs for detailed grinding and carving after the final bake. I studied morphology at the Osaka Ceramic Training Centre in Japan with Shigeo Kataoka-sensei. According to him, a key factor in creating a perfect macro and micro morphology lies in the shadows. To be able to take into account the interference of light and shadow during grinding, a light source is placed on one side of the restoration.

How many bakes do you need to produce highly aesthetic restorations?

It depends on the case, although in many situations, I nowadays opt for some kind of micro-layering. Lately, I have used micro-layering a lot with internal stain directly on the zirconia framework. In other cases, I do a quick first bake, then the internal staining, a final bake and glazing. For small or single-unit restorations in the posterior region, a One-Bake Technique is often sufficient. Even a Zero-Bake approach using Esthetic Colorant on a monolithic zirconia restoration may be appropriate here, and it is very convenient. If there is a restoration with high aesthetic demands – these are typically single anterior restorations – the technique I select depends on the shade. In some cases, using only the internal stain technique is enough to reach a high aesthetic level, while in other cases, additional steps need to be taken. To my mind, there is no single technique that fits all cases. As mentioned before, I try to achieve high aesthetics in a minimum of time.

Fig. 6. Clinical example of achieving high aesthetics in a minimum of time: Before …

Fig. 7. … and after crown placement.

Fig. 8. High aesthetics …

Fig. 9. … achieved in a minimum of time.

Did your approach change due to the availability of high-translucency zirconia materials with colour (and flexural strength) gradation?

Well, yes! My overall approach changed more to micro-layering. Several years ago, we needed to consider how to mask the framework and how to achieve translucency in areas with limited space. The problem was solved for single-unit and small anterior bridge restorations with the availability of KATANA™ Zirconia UTML and STML. With the introduction of KATANA™ Zirconia YML, a high-translucency material became available for long-span or implant-based restorations as well. We have strength and translucency all in one disc. In most of my cases, the framework material replaces the dentin with regard to morphology and shade. Hence, I need to focus on adding the enamel by applying the transparent and translucent powders. The powders of the internal stain technique are used to characterize the framework, and with a micro-layer of porcelain, the goal of creating an aesthetic restoration in the minimum of time is achieved. This is exactly why I am sure that micro-layering is the future.

What drives you to share your knowledge with others?

My passion! I love my work! And I love to see technicians become better and better. Dental technology is an exciting journey, a journey that begins when the first impression arrives in the dental laboratory, and it ends when the final restoration is cemented into the patient’s mouth. And this journey is so exciting because we change lives. We change people’s personalities, we give them back their smile, we give them back their self-respect. Consider that every day, every single moment working on our bench trying to imitate nature… there is nothing more exciting than that!!!

My approach as an instructor is to lead dental technicians to master the art of observing natural teeth. This is the way every individual will understand morphology and shade. You need no special talent to be a very good dental technician. You need to observe! Your eyes see, your mind understands, and your hands will follow.

Alexander (Alek) Aronin is a master dental technician who dedicated himself to the creation of high-end, handmade porcelain restorations. He runs a dental laboratory and morphology school in Spain, and travels the world as a lecturer and teacher.

The greatest source of inspiration in his professional life is the book Collection of Ceramic Works by Hitoshi Aoshima. Through reading it in 1996, he discovered superb outcomes of working with dental ceramics. Moreover, the book’s content made him realize that the creation of handmade porcelain work is a result of special education and manual skills. Those who want to become masters need a lot of commitment and a striving for continuous improvement, which Alek shows in his work and his classes. We talked to him about his philosophy and his enthusiasm for the creation of lifelike restorations. He shared with us his perspective on the future of dental technology and gave some practical tips on how to achieve a high level of professional satisfaction.

Photo courtesy of Dennis Debiase

Alek, many dental technicians decide to focus on CAD/CAM technology and automated processing of dental ceramics. Due to improvements on the material side, a handmade porcelain layer is no longer necessary in many clinical cases. In this context, the manual refinement process is reduced to a minimum. Why did you decide to take a completely different path and focus on fully manual dental craftsmanship?

The shift towards automated processing is not a matter of choice for dental technicians rather, it is a natural response to the evolution of technology. The high-end manual refinement process remains unchanged. The human element, from communication to hand crafting among skilled individuals and demanding clients, has been a constant so far throughout history. This traditional connection remains stable for centuries.

Digitalisation is not the revolution in the dental industry, and I do not see the benefit of it in our narrow specialization yet. In the area we are working, we do all steps of our case faster, incomparably more precise and more profitable. But we are keeping eye on machines and waiting for a suitable one.

Machines and automated processes widely serve mass production businesses focused on fast, affordable and uniform results in a highly competitive field. Our goal and workflow are different - we provide individual work and personal attention to each of our partners and patients.

So, we do not compete with the production labs and do not interrupt each other, we coexist in parallel worlds as always. A small number of dentists and their patients will always demand personal attention and valued restorations and service of the highest quality.

Many dental technicians admire your work. Yet, you continue to strive for improvement. Why is this the case?

On one side, we are limited by static ceramic material used to mimic dynamic natural teeth that keep changing for a lifetime. On the other side, we are limited by our manual skills. I am still far away from my teachers and Japanese colleagues. My target is to improve the fabrication process. My goal is to achieve the simplicity and imperfectness like Aoshima-sensei.

Alek lecturing at the IDS 2023 in Cologne.
Photo courtesy of Dennis Debiase

We are enjoying the outcome, but prefer to focusing on the improvement of the process, and move on to create a better one. This is what I am learning in Japan, and this is what I teach my students.

Talking about learning: What are the most important aspects a dental technician who wants to improve his skills should have in mind when looking for a good teacher?

Manual skills are very important, but not the only aspect that should be taken into account. Every individual should be motivated and guided and this is a teacher’s job.

I love the traditional Japanese way of teaching and learning: The teachers are passionate, leading the way by evoking emotions and manual skills to bring the best out of every single student. My personal advice for dental technicians who want to become masters in the creation of lifelike high-end dental restorations is to select their teachers carefully and go to a private school or courses whenever they have the chance.

What are the most important tools a dental technician needs to use when trying to create high-end lifelike restorations?

I suggest to focus on four aspects:

1. Documentary dental photography - required for documentation and communication with the dental office and patients using constant (once set and never changed) parameters of the photo equipment.
2. Focus to the biomimetic additive dentistry. This is a minimum machine invasive field. Dental technicians and dentists should be able to develop a deep knowledge about clinical and lab-side procedures to be able communicate with each other.
3. Mastering morphology and function (shape carving), and anatomy (internal staining), which comes with value control and mimicking fine tooth details for best integration in the mouth.
4. Written communication (stop phone calls) is very important, this is the way how to exchange the information between the patient, clinic and lab by strict protocols.

I teach these complex skills in my morphology school and in many of my trainings worldwide. Focusing on the four aspects, a dental technician has a great chance to become a good specialist in a relatively short period of time in a narrow field.

Is material selection important for achieving great results?

I’ve been using Noritake ceramic for most of my life, and the reason is simple: Noritake created their EX-3 porcelain over 40 years ago, and it was so well-made that it has not needed any changes since.

This is showing their consistently high quality and creates unbroken succession in the valuable tradition of passing on techniques and knowledge.

Today, among different generations of dental technicians, we can use and share the same methods, vocabulary and abbreviations, powders, and temperature charts developed by our skilled teachers 30 to 40 years ago. This unique feature sets Noritake and Creation porcelains apart from all other brands and systems in the world.

The other Noritake porcelain I use quite frequently is CERABIEN™ ZR, which is also well-tried and tested and has even some more advantages than EX3.

Is there any final advice you would like to give?

To become a good professional, I suggest to developing in four parallel directions:

1. Practicing on phantoms - fabricating cases and ceramic samples. It helps to experiment and practice with varied materials and techniques.
2. Implementing the achieved techniques in clinical cases.
3. Working with case presentation PowerPoint or Keynote: documenting the working steps in pictures and videos from beginning to end.
4. Mastering the communication using e-mails. Constantly calibrate and adjust the information exchange process between the clinic and lab. Acquire deeper knowledge about the work of each other.

Good luck!

Interview with Mitsunobu Kawashima
Manager, Technology Division of Kuraray Noritake Dental Inc.

In 1983 – exactly 40 years ago – PANAVIA™ EX was introduced in Japan as the first product of the PANAVIA™ family and the first product containing the original MDP monomer. Since then, the PANAVIA™ family of resin cements has been continuously expanded by developing new resin-cement materials that are precisely adjusted to the contemporary demands of dental practitioners. The current line-up of easy-to-use, high-performance adhesive luting materials is globally available and used by dental practitioners with high quality standards.

We had a conversation with Mr. Mitsunobu Kawashima about PANAVIA™ EX as a ground-breaking innovation in the field of dental resin cements and subsequent steps toward the current well-balanced resin cement portfolio. He is currently responsible for the development of chair-side materials in the Technology Division of Kuraray Noritake Dental Inc. (Kuraray Noritake Dental) and has been part of the team developing the many products of the PANAVIA™ family for more than 30 years.

The resin cements developed by the company before the introduction of PANAVIA™ EX contained the adhesive monomer Phenyl-P. Why did you decide not to use Phenyl-P in the new formulation?

At the time we decided to develop PANAVIA™ EX, we were engaged in the development of new adhesive monomers to replace Phenyl-P. The main aim of this project was an improvement of our products’ bond strength to metal alloys and dentin. Among the new adhesive monomers being developed, we decided to use the MDP monomer, because it features excellent bonding to tooth structure and metal alloys used in dentistry, as well as superb resistance to water. Incidentally, our first products to contain the original MDP monomer were the resin cement PANAVIA™ EX and the bonding agent CLEARFIL™ NEW BOND.

Where did the name PANAVIA™ come from?

The name “PANAVIA™” is a compound word consisting of “PAN” and “VIA”. The former is of Greek origin, and the latter is of Latin origin. “PAN” means “everything” and “VIA” means “way” or “method”. Consequently, the name “PANAVIA” describes a “method for bonding everything”; it represents our desire to have products launched under the umbrella of the PANAVIA™ brand recognized as dental materials that can bond to all types of restoration and tooth structure.

Would you please tell us the story behind the development of PANAVIA™ EX?

Back in the early 1980s, it was indispensable for us to develop new adhesive monomers as a part of our project to develop a new resin cement with unprecedented adhesive properties. In this context, we conducted a comprehensive literature search for compounds thought to be involved in adhesion. At the same time, we carried out a variety of R&D activities, including basic research to quantitatively clarify the relationship between the molecular structures of monomers and their adhesive qualities, synthesis trials of various monomers and bond strength tests. Consequently, we succeeded in developing the MDP monomer that had the physical properties we were working to obtain. Following the development of that MDP adhesive monomer, we were finally able to create PANAVIA™ EX in our laboratory. In early 1982, we completed the first prototype of PANAVIA™ EX for external evaluation and asked a dental college in Japan to evaluate it. He found that the prototype cement might cure too quickly in clinical use. This was due to the fact that we had not taken into account the difference between room temperature and intraoral temperature, which has a huge impact on the curing time. This error led us to recognize how important clinical evaluations are during the development of dental materials. To this day, we continue to place great importance on the opinions of clinicians whenever a new material is being developed.

The name “PANAVIA™” is a compound word consisting of “PAN” and “VIA”. The former is of Greek origin, and the latter is of Latin origin. “PAN” means “everything” and “VIA” means “way” or “method”.

What were the key technological features of this new PANAVIA™ EX cementation system?

The system had five key features: Appropriate film thickness, appropriate flow properties of the paste, radiopacity, improved bond strength and improved surface-cure characteristics. At the time that PANAVIA™ EX was developed, a film thickness of 30 μm or less was desired for luting cements. The largest components we wanted to use in the formulation – the silica filler particles present in our composite resin – had a maximum particle diameter of 50 μm. We were able to achieve a film thickness of 30 μm or less by significantly extending the silica grinding time, which made the filler particles much finer. An appropriate paste consistency – a low level of viscosity and good flowability – was achieved by using low-viscosity monomers for PANAVIA™ EX. In order to make the cement radiopaque, we dispersed radiopaque filler within the powder component. In fact, we were convinced that it was essential to be able to check for the presence of excess cement under the gingival margins after a restoration was placed. The increase in bond strength was achieved by blending the MDP monomer into the liquid component.

What about the surface-cure characteristics of the cement?

Every dental practitioner knows that the surface of resin cements must be protected from oxygen in the air in order to cure properly. For this purpose, we developed OXYGUARD, a water-soluble gel material. It is applied to the restoration margins to cover the unpolymerized resin cement surface and protect it from exposure to oxygen. In this way, the formation of an oxygen inhibition layer – a layer of uncured resin on the surface that compromises the marginal integrity of the restoration – is prevented and an intact, fully polymerized cement surface can develop. In this way, the use of OXYGUARD has contributed greatly to improving the cure characteristics of cements.

What do today’s PANAVIA™ products and PANAVIA™ EX have in common?

The PANAVIA™ family of products, including PANAVIA™ EX, share the concept of “being a resin cement product that opens new dimensions in dentistry”. PANAVIA™ EX was our first resin cement, and it was conceived as a cement for a new era. It can bond to tooth structure and dental metals very well, thanks to the use of the MDP monomer. This important adhesive monomer is still used today in many of our products. Ever since the launch of PANAVIA™ EX, Kuraray Noritake Dental has continued to take on new challenges and has developed many new products in the growing PANAVIA™ family. These include PANAVIA™ 21, a cement in paste form that has a self-etching primer as an accessory; PANAVIA™ Fluoro Cement, a dual-cure cement paste that releases fluoride; and PANAVIA™ F2.0, which can be used with an LED curing unit. The current portfolio consists of PANAVIA™ V5, which features the substantially improved bonding performance that was achieved after a major review of the basic composition of the series, PANAVIA™ SA Cement Universal, which works as a standalone product without separate primers, and PANAVIA™ Veneer LC, PANAVIA™ family’s latest product. The latter is a light-curing resin cement with the specialized purpose of bonding laminate veneers.

In retrospect, what did the introduction of PANAVIA™ EX mean to Kuraray Noritake Dental?

In the development of new resin cements, it is important to quickly respond to the rapidly changing trends in the market. Whenever new prosthodontic treatment concepts appear – like adhesive bridges as a minimally invasive treatment option replacing a single tooth – or new restorative materials are introduced, such as different types of ceramics – we need to check if our resin cement systems are compatible with the tasks that come with these changes, as well as possibly developing new ones. Following the launch of PANAVIA™ EX, we received a wide range of feedback from experts working at dental clinics and laboratories. We leveraged this feedback in subsequent development projects, always striving to stick close to the clinical setting. After Kuraray Medical Inc. merged with Noritake Dental Supply Co., Limited, this ethos was embedded in the work ethic of all employees of Kuraray Noritake Dental.

Can you give us a brief history of the PANAVIA™ EX journey to the currently available PANAVIA™ family portfolio?

Since the launch of PANAVIA™ EX 40 years ago, six different PANAVIA™ products have been released. Each of them has received high acclaim for their unique features, both in the Japanese resin cement market and abroad. For 40 years, we have been improving PANAVIA™ in response to the demands of the times. We developed a product with increased adhesion when non-retentive preparation designs (adhesive bridges) and smaller bonding surfaces (due to less invasive preparations) became popular. And for users concerned about secondary caries, we developed a material with fluoride-releasing properties. At the same time, we focused strongly on making dental cementation easier by finding ways to make our resin cements bond well to various types of crown-restoration materials, including precious metals and ceramics. During these drives towards improvement, “achieving reliable general luting” has always been at the forefront of our goals. We believe that the successful evolution of the PANAVIA™ brand owes a great deal to our incessant efforts to obtain a high level of bond strength to dentin after chemical polymerisation”.

How did the R&D department evolve over the years?

Initially, our efforts in the development of dental materials had focused on bonding agents and restorative composite resins. PANAVIA™ EX was just one of our new development projects and only a few staff members were assigned to that product. After PANAVIA™ EX was launched in 1983 and it was accepted worldwide, our product line-up of resin cements was expanded considerably. Consequently, we have increased the number of development staff assigned to resin cements and set up a special development team responsible for the self-adhesive resin cement product line that includes PANAVIA™ SA Cement Universal. As a result, the size of the team assigned to resin cements has expanded substantially.

How did production change?

When PANAVIA™ EX was launched in 1983, the product was manufactured exclusively for the Japanese market in a relatively small facility. Today, in order to produce all products of the PANAVIA™ family for the global market, we have automated our production facilities and increased the production equipment and systems dedicated to producing the resin cement paste. To support our product quality, we have also set up a quality control system that assures we turn out safe and high-quality products, drawing on over 40 years of technical knowhow and experience in the production of resin cements.

For 40 years, we have been improving PANAVIA™ in response to the demands of the times.

When did external researchers start showing interest in PANAVIA™?

The development of PANAVIA™ EX was carried out with the active participation of researchers at a dental college in Japan, involving such activities as performing basic adhesion tests and experimenting with clinical applications using adhesive bridges. At that time, resin cements that provided a strong bond to tooth structure or metal alloys were not widely used. I believe that overseas researchers were interested in the development of PANAVIA™ EX at a relatively early stage, for this reason.

What current concept do you have in mind as you continue developing your adhesive cements?

We have two basic central concepts: “Achieving greater bond strength” and “Delivering easier handling characteristics”. I think that the shades of resin cements are also devised in each product in order to get the most of the characteristics of aesthetic restorative materials. At our company, we have embodied “achieving greater bond strength” in PANAVIA™ V5, and “delivering easier handling characteristics” in PANAVIA™ SA Cement Universal. We will continue to explore the development and introduction of various new technological applications, to bring even higher performance products to market.

What do you think is the strength of Kuraray Noritake Dental’s R&D team?

We conduct R&D activities continuously, focusing on the development of luting materials. In our product development department, the same person is often responsible for one product category over long period of time. For example, I have been engaged in the development of PANAVIA™ products for much of my time with the company. The result is that each person in the development department can be said to be an expert in a certain category of products. They leverage the technical knowledge acquired in the past for the development of new products, resulting in entirely new discoveries.

Do you have any ideas about what the future of PANAVIA™ will be?

We will continue to focus on the development of even simpler, easier-to-use resin cements suitable for a wide range of applications – products based on the concept of universality. This should allow users to focus more on the actual treatment than ever before, while of course delivering a strong and durable bond between the tooth structure and the restoration.

MITSUNOBU KAWASHIMA

Eight-time DENTAL ADVISOR Top Product selection provides effective relief for a painful condition

Dentine hypersensitivity is a painful condition that affects millions of people worldwide. It generally occurs when tubules are exposed for any number of reasons, including gingival recession, dental erosion or excessive tooth brushing. It can also be a side effect of professional tooth cleaning, scaling and root planning, tooth whitening, or restorative procedures.

TEETHMATE™ DESENSITIZER, which was honored by DENTAL ADVISOR every year from 2015 to 2022 as a Top Product selection, allows an effective non-invasive approach to the treatment of hypersensitivity when used as directed by dental professionals.

TEETHMATE™ DESENSITIZER is designed to crystalize hydroxyapatite (HAp), a mineral that is naturally found in enamel and dentin, and is the human body’s strongest material. When applied to exposed, mechanically treated, or freshly prepared dentin, the calcium phosphate based mixture blocks the exposed tubules and provides immediate pain relief. During setting, HAp is formed, providing for long-term prevention of hypersensitivity. Further, when used in the context of restorative treatment, TEETHMATE™ DESENSITIZER does not have a negative effect on the bond strength of subsequently utilized dental adhesives or cements.

DENTAL ADVISOR clinical study found TEETHMATE™ DESENSITIZER effective in providing hypersensitivity relief immediately following and for up to six months after application. The study evaluated 27 patients diagnosed with gingival recession-related hypersensitivity, which was diagnosed using thermal testing with cold air. For the initial assessment, patients were asked to evaluate their level and frequency of hypersensitivity per tooth on a five-point scale. They were questioned about their level of sensitivity immediately after TEETHMATE™ DESENSITIZER was applied, according to the instructions for use, and again six months later. At baseline, 91 percent of the patients stated that they had no or only mild, sporadic sensitivity, which was still the case for 85 percent after six months.

This natural, tissue-friendly product is highly biocompatible and is free of gum irritants such as glutaraldehyde or methacrylates. It is indicated for use by dental professionals for all  sensitivity challenges in everyday practice, including prevention of cervical hypersensitivity before/after bleaching, scaling or root planning, and underneath restorations.

The Top Product or Preferred Product Awards conferred by US-based DENTAL ADVISOR were introduced to support potential users in identifying high-quality dental materials and determining which among them are best suited to fulfill their individual requirements. Awards are based on results of its practice-based clinical evaluations and product performance tests, which are conducted shortly after product launch.

Among products honored this year are five from Kuraray Noritake Dental Inc.: CLEARFIL™ SE Protect, CLEARFIL MAJESTY™ ES Flow (Low), and PANAVIA™ SA Cement Universal were selected as Top Products; and CLEARFIL™ Universal Bond Quick and CLEARFIL™ CERAMIC PRIMER PLUS were chosen as Preferred Products.

Article by Dr. Adham Elsayed

High-performance adhesive resin cements are often the enablers of minimally invasive prosthodontic treatments. When the main aim is to save as much healthy tooth structure as possible, preparation designs that offer sufficient macro-mechanical retention for conventional cements are usually abandoned. The designs chosen instead need to rely on a strong and durable chemical adhesion established between the tooth structure and the restorative material – a task successfully accomplished by modern adhesive resin cement systems.

An excellent example of a minimally invasive, non-retentive preparation and restoration design is the single-retainer resin-bonded fixed dental prosthesis (RBFDPs), nowadays usually made of 3Y-TZP zirconia. With its single cantilever bonded to the oral and proximal enamel surface of an adjacent tooth, it requires minimal to no healthy tooth structure removal. The RBFDP is often used to replace a congenitally missing tooth – in many cases a maxillary lateral incisor – in young patients with incomplete dentoalveolar development and narrow edentulous spaces unsuitable for conventional implant placement¹ (Fig. 1 and 2). Additional factors hindering implant therapy – like an insufficient bone volume or angulated roots – are also not an issue for this type of restoration. And compared to orthodontic gap closure, the treatment approach with a RBFDP is less risky, as it does not affect the vertical jaw relationship, prevent canine guidance or compromise the aesthetic appearance². Finally, it is much less invasive than conventional FDPs, which is usually not a treatment option for young patients in the anterior region. The level of patient satisfaction and the success rates of this treatment approach are impressive^3-7.

Fig. 1-2. Replacement of both congenitally missing maxillary lateral incisors with single-retainer zirconia RBFDPs after soft tissue augmentation and gingival margin correction.

Despite the numerous advantages and excellent clinical performance – single-retainer RBFDP made of zirconia showed a survival of 98.2 percent and a success rate of 92.0 percent after ten years⁴ – many dental practitioners still opt for alternative treatment options. The reason may be a lack of trust in the bond strength and durability to zirconia. However, this bond can be very strong and durable – provided that a few rules are respected.

HOW TO ESTABLISH A STRONG BOND TO THE TOOTH STRUCTURE

In order to decide whether a missing tooth may be successfully replaced by a single-retainer RBFDP made of zirconia, the abutment tooth should be examined carefully. It needs to be vital and largely free of caries or direct restorations, while the oral enamel surface must be large enough for resin bonding¹. In addition, the space required for the placement of a retainer wing (thickness: about 0.7 mm) needs to be available, as a non-contact design is important for the success of the restoration. Among the preparation designs described in the literature is a lingual veneer and small proximal box preparation with retentive elements located in the enamel only¹, or no preparation at all⁷. For restoration placement, the abutment tooth is treated as usual: after cleaning e.g., with fluoride-free prophylaxis paste, phosphoric acid etchant is applied to the bonding surface, which is then thoroughly rinsed and dried.

HOW TO ESTABLISH A STRONG BOND TO THE RESTORATION

The recommended pre-treatment for the bonding surface of the retainer wing made of zirconia is small-particle (50 μm) aluminium oxide air-abrasion at a low pressure (approx. 1 bar)^8,9, followed by ultrasonic cleaning. Figures 3 (A-E) shows the sequence of surface treatment of zirconia restorations. As a visual aid for a controlled air-abrasion treatment, the marking of the surface with a pen has proven its worth. The whole air-abrasion procedure should be carried out after try-in, during which the tooth surface and the restoration usually becomes contaminated through contact with saliva and sometimes blood. Proteins present in saliva and blood that contaminate the bonding surface are safely removed in this way, while the required surface modification necessary to establish a strong and durable bond to the selected resin cement system is achieved¹⁰.

FIGURE 3: SEQUENCE OF SURFACE TREATMENT OF ZIRCONIA RESTORATION.

Fig. 3A. Cleaning of the restoration prior to luting with water steam cleaner.

Fig. 3B. Marking of the bonding surface as an visual aid for the air-abrasion.

Fig. 3C. Air-abrasion with 50-μm Al₂O₃ particles with 1 bar pressure.

Fig. 3D. Application of a primer containing 10-MDP.

Fig. 3E. Application of the composite resin cement.

WHICH RESIN CEMENT SYSTEM TO CHOOSE

Subsequently, the components of the resin cement system are applied. Regarding the selection of the system, it is generally recommended to use a restoration primer or resin cement that contains 10-Methacryloyloxydecyl dihydrogen phosphate (10-MDP)¹¹. In this way, a high-quality chemical bond is established. Among the resin cement systems used in the available long-term clinical studies is PANAVIA™ 21 (Kuraray Noritake Dental Inc.)^4-6. Launched in 1993, this anaerobic-curing adhesive resin cement contains several important technologies like the MDP monomer and the Touch Cure Technology found in PANAVIA™ V5, the state-of-the art dual-cure multi-bottle adhesive resin cement system of the company. In order to further improve the bonding performance of this present product, however, the team of developers reviewed the basic composition, updated existing technologies and combined them with completely new ingredients.

Even with PANAVIA™ 21 introduced 30 years ago, high success rates were obtained^4-6. The few observed failures were mainly due to chipping of the veneering ceramic or debonding. Sometimes caused by traumatic incidents, the debondings resulted in no further damage and the restorations were simply rebonded using the same cementation system and procedure.

One might expect that with its improved formulation, PANAVIA™ V5 will offer an even stronger and more durable bond than predecessor products, so that it is even better suited for such demanding applications as the resin-bonded fixed dental prosthesis. In a pilot study, this assumption was confirmed⁷. Without any preparation of the abutment tooth, but a defined size of the bonding surface of at least 35 mm², the team of researchers placed 24 monolithic zirconia resin-bonded bridges (made of KATANA™ Zirconia HT) to replace congenitally missing lateral incisors. The palatal sides of the central incisors were cleaned with pumice paste and treated with phosphoric acid, while the bonding surfaces of the restorations were sandblasted with aluminum oxide particles (50 μm, 2.5 bar pressure). Afterwards, twelve restorations were luted with PANAVIA™ V5, the other twelve with PANAVIA™ F2.0 (another earlier-version resin cement from Kuraray Noritake Dental Inc.). After an observation period of 32 to 50.47 months, the success and survival rates in the PANAVIA™ V5 group were 100 percent. In the other group, a connector fracture, a chipping and two debondings occurred. Based on these results, the authors of the publication concluded that “it has been seen that the new generation cement (PANAVIA™ V5) is more successful”⁷.

CONCLUSION

For many years, minimally invasive indirect restorative approaches like the replacement of missing incisors with resin-bonded fixed dental prostheses have been performed successfully by some dental practitioners. Many others, however, still seem to be hesitant whether these approaches will lead to the desired results in their hands. The available clinical study results, however, have confirmed that the procedure is highly advantageous and successful, while ongoing development efforts in the field of adhesive resin cements have led to products further decreasing the failure rates related to debonding. Even if a debonding occurs, however, no damage is usually done, so that the restoration can be rebonded again with little effort. These findings – together with the well-known benefits of minimally invasive dentistry in general – should encourage dental practitioners to start exploring the full potential of adhesive dentistry for themselves. In this context, PANAVIA™ V5 is definitely an excellent choice.

References

1. Sasse M, Kern M. All-ceramic resin-bonded fixed dental prostheses: treatment planning, clinical procedures, and outcome. Quintessence Int. 2014 Apr;45(4):291-7. doi: 10.3290/j.qi.a31328. PMID: 24570997.
2. Tetsch J, Spilker L, Mohrhardt S, Terheyden H (2020) Implant Therapy for Solitary and Multiple Dental Ageneses. Int J Dent Oral Health 6(6): dx.doi. org/10.16966/2378-7090.332.
3. Wei YR, Wang XD, Zhang Q, Li XX, Blatz MB, Jian YT, Zhao K. Clinical performance of anterior resin-bonded fixed dental prostheses with different framework designs: A systematic review and meta-analysis. J Dent. 2016 Apr;47:1-7. doi: 10.1016/j.jdent.2016.02.003. Epub 2016 Feb 11. PMID: 26875611.
4. Kern M, Passia N, Sasse M, Yazigi C. Ten-year outcome of zirconia ceramic cantilever resin-bonded fixed dental prostheses and the influence of the reasons for missing incisors. J Dent. 2017 Oct;65:51-55. doi: 10.1016/j.jdent.2017.07.003. Epub 2017 Jul 5. PMID: 28688950.
5. Kern M. Fifteen-year survival of anterior all-ceramic cantilever resin-bonded fixed dental prostheses. J Dent. 2017 Jan;56:133-135.
6. Sasse M, Kern M. Survival of anterior cantilevered all-ceramic resin-bonded fixed dental prostheses made from zirconia ceramic. J Dent. 2014 Jun;42(6):660-3. doi: 10.1016/j.jdent.2014.02.021. Epub 2014 Mar 5. PMID: 24613605.
7. Bilir H, Yuzbasioglu E, Sayar G, Kilinc DD, Bag HGG, Özcan M. CAD/CAM single-retainer monolithic zirconia ceramic resin-bonded fixed partial dentures bonded with two different resin cements: Up to 40 months clinical results of a randomized-controlled pilot study. J Esthet Restor Dent. 2022 Oct;34(7):1122-1131. doi: 10.1111/jerd.12945. Epub 2022 Aug 3. PMID: 35920051.
8. Kern M. Bonding to oxide ceramics—laboratory testing versus clinical outcome. Dent Mater. 2015 Jan;31(1):8-14. doi: 10.1016/j.dental.2014.06.007. Epub 2014 Jul 21. PMID: 25059831.
9. Kern M, Beuer F, Frankenberger R, Kohal RJ, Kunzelmann KH, Mehl A, Pospiech P, Reis B. All-ceramics at a glance. An introduction to the indications, material selection, preparation and insertion techniques for all-ceramic restorations. Arbeitsgemeinschaft für Keramik in der Zahnheilkunde. 3rd English edition, January 2017.
10. Comino-Garayoa R, Peláez J, Tobar C, Rodríguez V, Suárez MJ. Adhesion to Zirconia: A Systematic Review of Surface Pretreatments and Resin Cements. Materials (Basel). 2021 May 22;14(11):2751.
11. Al-Bermani ASA, Quigley NP, Ha WN. Do zirconia single-retainer resin-bonded fixed dental prostheses present a viable treatment option for the replacement of missing anterior teeth? A systematic review and meta-analysis. J Prosthet Dent. 2021 Dec 7:S0022-3913(21)00588-6. doi: 10.1016/j.prosdent.2021.10.015. Epub ahead of print. PMID: 34893319.

KATANA™ Zirconia STML and PANAVIA™ SA Cement Universal

Photo: KATANA ™ Zirconia STML NW with CERABIEN ™ ZR FC Paste Stain
Sergio R. Arias DDS, MS Sung Bin Im, MDC, CDT

KATANA™ Zirconia STML on väga populaarne materjal, mida kasutatakse paljudes hambalaborites üle kogu maailma. Võrreldes traditsiooniliste tsirkooniumist karkassmaterjalidega, millel on põhiliselt nelinurkne polükristalne struktuur, on sellel materjalil suurem ütriumi sisaldus, mis annab teistsuguse materjali struktuuri, mõjutades optilisi ja füüsilisi omadusi (läbipaistvus suureneb, paindetugevus väheneb). Seetõttu on näidustuste vahemik piiratud üksikute hammaste restauratsioonidega ja kahe- kuni kolmeosaliste sildadega esi- ja tagahammaste piirkondades. Suurim eelis seisneb palju suuremas esteetikas, mis tuleneb asjaolust, et materjali kasutatakse peamiselt, et valmistada monoliitseid restauratsioone ja restauratsioone, mille mikrotagasilõige on kaetud portselanist mikrokihiga.

Kuigi näidustused ja tehniline protseduur on hästi teada, on vähem teada hambaravikabinetis töötlemise kohta. Kas standardne tsementimine on võimalik ja soovituslik või on eelistatud adhesiiviga kinnitamise protseduur? Kas pinna eeltöötlus on sama, mis tetragonaalsel tsirkooniumil, või on vajalik teistsugune protseduur? Milline on KATANA™ Zirconia STML restauratsioonide pikaajaline toime? Nendele küsimustele heidab valgust teadusliku kirjanduse põhjalikum
ülevaade.

KATANA™ Zirconia STML-ist valmistatud restauratsioonide püsipaigaldus

Standardne tsementimine või adhesiiviga kinnitamine? Põhimõtteliselt on mõlemad protseduurid võimalikud, kui paigaldataval restauratsioonil on retentsiivne ülesehitus. Üldiselt arvatakse, et täiskattekroon annab piisava retentsiooni tavapärase tsementimise korral, kui abutmendi hammas on vähemalt 4 mm kõrge ja aksiaalsete seinte ühitusnurk on vahemikus 6 kuni 12 või maksimaalselt 15 kraadi.1,2

Põhjus on selles, et materjali paindetugevus on suurem kui 350 MPa3, mis on tavapärase tsementimise kriitiliseks väärtuseks. Ent kuna tavapärased tsemendid
on opaaksed ja saadaval ühe toonina, võib esteetilistel põhjustel eelistada (ise-)siduva vaiktsemendi kasutamist kõigi suure läbipaistvusega restauratiivmaterjalidega. Igal juhul on nende toodete kasutamine kohustuslik, kui makroretentsiivse preparatsiooni ülesehitus ei ole võimalik või tahetud. Kokkuvõtteks on isesiduva või adhesiivse vaiktsemendi kasutamine paljudes olukordades eelistatud. Isesiduvate vaiktsementide kasuks räägib see, et neid on
lihtne kasutada.

Kuidas tsirkooniumi eeltöödelda? Ükskõik millist tsirkooniumi tüüpi kasutada, on hüdrofluorhappega söövitamine ebaefektiivne, kuna materjalis on vähe klaaskiudu. Selge on aga see, et pinna muutmine on vajalik, et saada tugev ja vastupidav adhesioon mistahes vaiktsemendisüsteemiga4,5

Üldiselt tugeva tsirkooniumi töötlemise meetod on liivapritsimine alumiiniumoksiidiosakestega või tribokeemilise ränidioksiidiga katmine4. Osakeste suurus peab olema väike (≤ 50 μm) ja rõhk madal (u 1 baar), et vältida materjali mehaaniliste omaduste nõrgenemist3,4. Mitte nii tugevate materjalivariantide puhul on materjali nõrgenemise oht suurem5, mistõttu on eriti oluline töötada madalama rõhu ja väiksemate osakestega5-8. KATANA™ Zirconia puhul teatati aga et „alumiiniumoksiidiga liivapritsimine suurendas oluliselt KATANA™ STMLi biaksiaalset paindetugevust.“9 See tähendab, et KATANA™ Zirconia STMList valmistatud
restauratsioonide liivapritsimine ei mõjuta materjali paindetugevust, vaid see isegi suureneb Kuraray Noritake Dentali tsirkooniumi eriomaduste tõttu.

Nende leidude põhjal on suure läbipaistvusega tsirkooniumi puhul soovitatud järgmised protseduurid:

1. VÕIMALUS
Alumiiniumoksiidi õhkabrasioon, selle järgselt 10-MDP-d sisaldava isesiduva vaiktsemendi kasutamine6

2. VÕIMALUS
Tribokeemilise ränidioksiidiga katmine, selle järgselt sidumispinna silaanimine6

Kuna kahelikõvastuv isesidustuv PANAVIA™ SA Cement Universal sisaldab originaalset MDP-monomeeri ja pika süsinikuahelaga silaanist sidusainet (LCSi-monomeer), sobib see mõlemaks protseduuriks.

PANAVIA™ SA Cement Universal on saadaval automaatselt segavas süstlas ja käsitsi segatava süsteemina ning koosneb kahest pastast. Üks pasta sisaldab originaalset MDP-monomeeri hüdrofiilsete monomeeride keskkonnas ja teine sisaldab inaktiivset LCSi-monomeeri hüdrofoobsete monomeeride keskkonnas. Pastade doseerimisel segatakse need süstla segamisotsakus (automaatne segamine) või doseeritakse segamisalusele ja segatakse käega (käsitsi segamine). Pärast lisatakse materjal lihtsalt restauratsiooni mudelile ja restauratsioon paigaldatakse. Üleliigset tsementi on lihtsaim puhastada pärast nakkekõvastumist (2 kuni 5 sekundit).

Kas see töötab ka kliinilises keskkonnas?

Parim viis, kuidas kontrollida, kas kirjeldatud protseduur on kliinilises keskkonnas edukas, on kliinilise uuringu läbiviimine. See on see, mida tegid Hispaanias University Complutense of Madrid uurijad, kasutades KATANA™ Zirconia STMLi ja PANAVIA™ SA Cement Universal materjali kombinatsiooni.10 Prospektiivse kliinilise uuringu raamistikus paigaldati 24 isikule, kes vajasid tagahammaste restauratsiooni, 30 KATANA™ Zirconia STMList valmistatud tagahammaste krooni. Hambad valmistati ette vastavalt täiskeraamilistele restauratsioonide puhul kehtivatele soovitustele, mis lubavad seinapaksuseks umbes 1 mm (KATANA™ Zirconia STMLi soovituslik minimaalne seinapaksus tagahammaste kroonidele: 1,0 mm). Restauratsioonid paagutati, isikupärastati ja glasuuriti
vastavalt materjali tootja soovitustele ning seejärel prooviti neid suhu. Enne tsementimist töödeldi restauratsioonide mudeleid alumiiniumoksiidi osakestega (50 μm, rõhk 1 baari), pärast mida puhastati neid ultraheliga. Ühtlasi oli PANAVIA™ SA Cement Universali kasutamine kooskõlas tootja soovitustega.

Kroonide kliiniline hindamine tehti pärast 6., 12. ja 24. kuud, kasutades California hambaraviühingu (CDA, California Dental Association) kvaliteedi hindamise süsteemi. Selles süsteemis hinnatud parameetrid on restauratsioonide pind ja värvus, nende anatoomiline kuju ja kroonide servade terviklikkus. Pärast 24. kuud olid edukuse ja püsimise määr 100 protsenti. Kõikide kolme näitaja koha pealt said kroonid „rahuldava“ (hindeks 3 või 4) hinnangu; servade terviklikkus
(põhiline parameeter, mis näitab vaiktsemendi toimivust) sai kõigi 30 juhtumi puhul hinnanguks „suurepärane“ (suurim võimalik hinne 4).

Järeldus

Uurijad järeldasid: „Selle uuringuga saadud suurepärased tulemused viitavad sellele, et kolmanda põlvkonna hambale toetatud tagahammaste monoliitsed tsirkooniumkroonid näivad olevat hea alternatiiv metallkeraamilistele kroonidele, teise põlvkonna monoliitsetele tsirkooniumkroonidele ja laminaadiga tsirkooniumkroonidele. Selle lühikese perioodiga uuringu tulemuste kinnitamiseks on vaja läbi viia pikaajaline uuring.“ Seega näib, et KATANA™ Zirconia
STML ja PANAVIA™ SA Cement Universal on paljulubav tandem, mis kasutatuna ülalmainitud protokollide kohaselt annab tõenäoliselt suurepäraseid tulemusi, mis püsivad stabiilsetena mitmeid aastaid.

References

1. Edelhoff D, Özcan M. To what extent does the longevity of fixed dental prostheses depend on the function of the cement? Working Group 4 materials: cementation. Clin Oral Implants Res. 2007;18 Suppl 3:193-204.
2. Güth JF, Stawarczyk B, Edelhoff D, Liebermann A. Zirconia and its novel compositions: What do clinicians need to know? Quintessence Int. 2019;50(7):512-20.
3. Kern M, Beuer F, Frankenberger R, Kohal RJ, Kunzelmann KH, Mehl A, Pospiech P, Reis B. All-ceramics at a glance. An introduction to the indications, material selection, preparation and insertion techniques for all-ceramic restorations. Arbeitsgemeinschaft für Keramik in der Zahnheilkunde. 3rd English edition, January 2017.
4. Comino-Garayoa R, Peláez J, Tobar C, Rodríguez V, Suárez MJ. Adhesion to Zirconia: A Systematic Review of Surface Pretreatments and Resin Cements. Materials (Basel). 2021 May 22;14(11):2751.
5. Mehari K, Parke AS, Gallardo FF, Vandewalle KS. Assessing the Effects of Air Abrasion with Aluminum Oxide or Glass Beads to Zirconia on the Bond Strength of Cement. J Contemp Dent Pract. 2020 Jul 1;21(7):713-717.
6. Chen B, Yan Y, Xie H, Meng H, Zhang H, Chen C. Effects of Tribochemical Silica Coating and Alumina-Particle Air Abrasion on 3Y-TZP and 5Y-TZP: Evaluation of Surface Hardness, Roughness, Bonding, and Phase Transformation. J Adhes Dent. 2020;22(4):373-382.
7. Alammar A, Blatz MB. The resin bond to high-translucent zirconia-A systematic review. J Esthet Restor Dent. 2022 Jan;34(1):117-135.
8. Soto-Montero J, Missiato AV, dos Santos Dias CT, Giannini M. Effect of airborne particle abrasion and primer application on the surface wettability and bond strength of resin cements to translucent zirconia. J Adhes Sci Technol, Online publication May 2022.
9. Inokoshi M, Shimizubata M, Nozaki K, Takagaki T, Yoshihara K, Minakuchi S, Vleugels J, Van Meerbeek B, Zhang F. Impact of sandblasting on the flexural strength of highly translucent zirconia. J Mech Behav Biomed Mater. 2021 Mar;115:104268.
10. Gseibat M, Sevilla P, Lopez-Suarez C, Rodríguez V, Peláez J, Suárez MJ. Prospective Clinical Evaluation of Posterior Third-Generation Monolithic Zirconia Crowns Fabricated with Complete Digital Workflow: Two-Year Follow-Up. Materials (Basel). 2022 Jan 17;15(2):672. (https://pubmed.ncbi.nlm.nih.gov/35057389/).

Article by Dr. Bassem Jaidane

Among the most common problems in modern dentistry is that of restoring a patient‘s lost aesthetic dental appearance. To do this, new technologies are available to practitioners. For anterior teeth where aesthetics are paramount, dentists prefer the least invasive treatments possible, such as layered dental veneers (cut-back). In cosmetic dentistry, practitioners are often faced with cases requiring a multidisciplinary treatment plan or different types of restorative materials to be used at the same time. For cases of prosthetic restoration combining dental veneers, dental crowns and dental bridges, dentists are often faced with situations where the difference in shade is noticeable in the final result, this is explained by the difference in restorative material, product, adhesion technique, the thickness of the prosthetic element and the colour of the abutment, whether it is a living natural tooth, devitalized, or even an implant abutment^1-2.

In the presence of a treatment plan requiring dental veneers, crowns and dental bridges, choosing zirconia as the only restorative material is no longer an option but an obligation. The is due to the limited mechanical properties of lithium disilicate and feldspar porcelain restorations, which contraindicate their use as dental bridges. There are different factors explaining the reluctance of practitioners to use the zirconia dental veneer technique³: One is the absence of the vitreous phase. It makes impossible to create an optimal adhesion surface with hydrofluoric acid at the level of the intaglio of the zirconia veneers. Another is the lack of translucency of the first zirconia generations.

Modern zirconia materials, however, are particularly well-suited for cases requiring a combination of veneers, crowns and dental bridges of the same optical appearance. This is due to their increased translucency and excellent mechanical properties. The following article describes and discusses the realization of a clinical case treated with dental veneers and a crown using KATANA™ Zirconia UTML (Kuraray Noritake Dental Inc.). the veneers were placed with PANAVIA™ Veneer LC (Kuraray Noritake Dental Inc.). The patient presented an aesthetic problem at the level of an anterior implant-supported crown.

CASE OBSERVATION

Patient S, from the Tunisian Sahel, engineer in France, with no significant pathological history and aged 29, presented in January 2023 due to an aesthetic problem negatively affecting her smile. The extraoral examination was without abnormalities, while the intraoral examination showed good oral hygiene, healthy gums, a thin free gingiva and a protruded zirconia crown on an implant in the region of the maxillary right central incisor (figs 1 and 2).

Fig. 1. Initial clinical situation.

Fig. 2. Occlusal view revealing the volume and position of the crown on the central incisor.

During the preliminary interview, it turned out that the implant in the region of the right central incisor had been placed in 2020. The patient’s former dentist had left Tunisian territory. The patient does not have any document or reference on the dental implant, and she wishes to “straighten” the crown and improve the aesthetics of her smile before her planned wedding ten days after her first consultation.

TREATMENT PLAN

After having had the informed consent of the patient and after having asked the indication of dental veneers for aesthetic reasons, the treatment was initiated. According to the treatment plan, seven maxillary anterior teeth (from first premolar to first premolar) should receive an incisal overlap preparation (depth: 0.1 to 0.3 mm) for the placement of veneers made of KATANA™ Zirconia UTML. For the implant in the region of the right central incisor, it was planned to replace the existing crown by a crown made of KATANA™ Zirconia UTML without replacing the abutment. This was due to the lack of information about the implant type and the lack of time.

TREATMENT

After taking the preoperative photos (fig 3), choosing the color of the veneers and anesthetizing the maxillary anterior region, the incisal overlap preparation was carried out on the seven maxillary teeth and the zirconia crown was removed from the implant. A cylindrical diamond bur was used to separate the zirconia part from the abutment. Subsequently, a bite record and impressions were taken using the wash technique. In addition, a temporary crown was produced and placed on the abutment.

Fig. 3. Preoperative picture.

In the dental laboratory, virtual models were created based on the conventional impressions (fig. 4). Then, the zirconia restorations were designed in full contour, cut back for the veneering porcelain and finished by layering with CERABIEN™ ZR porcelain (Kuraray Noritake Dental Inc.). At try-in during the second session, we checked the insertion, the gingival margins, and the contact points between the veneers and the crown on the implant. Given the superior mechanical properties of the zirconia veneer, the shape and thickness of the veneers were modified chairside to have a harmonious anterior curve and a better aesthetic rendering. After determining the colour of the resin cement, the temporary crown was put back in place.

Fig. 4. Virtual model.

After glazing and preparation of the bonding surfaces in the dental laboratory, the upper veneers were cemented according to the PANAVIA™ Veneer LC protocol. We ended the session by removing excess cement. An occlusion check and postoperative photos were taken after three days.

DISCUSSION

In this case, the dental veneers and the crown on the implant were produced using a KATANA™ Zirconia UTML disc. This type of zirconia has an yttrium oxide proportion of 5 mol%, leading to about 70 % cubic zirconia phase, and therefore a higher translucency than earlier generations of zirconia. With a translucency of 51 % (light transmission, illuminant: D65, specimen thickness: 1.0 mm. Source: Kuraray Noritake Dental Inc); this zirconia allows us to have remarkable optical properties (fig 5).

Fig. 5. Remarkable optical properties of the final restorations.

The patient chose color BL1 and requested a transparent incisal edge. For this reason, a cutback design of the zirconia (fig. 6) and porcelain layering was the technique of choice. Figure 7 shows the slight transparency in the incisal edge region of the new restorations. The zirconia veneers technique was chosen to avoid the color difference between the crown on the implant and the veneers. The pleasant aesthetic appearance and a harmonious smile are confirmed by the post-operative picture (fig 8). According to the manufacturer, the flexural strength of KATANA™ Zirconia UTML is 557 MPa, which is higher than that of lithium disilicate and feldspathic porcelains. As zirconia veneers will be more resistant to shear forces, it is possible to eliminate contact points that interfere during try-in or even safely modify the shape of the restorations in vivo. This is done with specific burs adapted to zirconia during different stages of the fittings according to the wishes of the patient⁴.

Fig. 6. Cutback design of the restorations.

Fig. 7. Slight transparency at the incisal edges of the restorations.

Fig. 8. Immediate post-operative picture.

In the present case, we were able to adjust the crown until we had a perfect anterior line. It was thus possible to optimize the inclination of the crown without replacing the dental implant, in just one week.

Given the significant shear resistance, the dental laboratory technician made zirconia dental veneers with an average thickness of 0.3 mm. Such a thin veneer requires less preparation of the dental tissue, which will be limited to enamel instead of extending into the dentin, where the adhesion value is lower due to its low chemical composition in minerals⁵.

The expected difficulty in bonding zirconia veneers is explained by the absence of a vitreous phase given the poor adhesion of the crystalline phase to the bonding cement. However, the desired surface modification can be achieved with a different procedure: tribochemical silica coating. It was used in the present case to improve the adhesion of the zirconia veneers to the resin cement system. Indeed, it was found in an in-vitro evaluation that the tribochemical preparation technique and the application of MDP provide an optimized adhesive interface⁶. In this study, dual-beam focused ion-beam technology followed by scanning electron microscopy were used to compare the resin/zirconia bonding interface with tribochemical preparation/MDP and the bonding interface between resin/zirconia without this preparation.

The tribochemical process consists of an aero-abrasion of the zirconia surface with particles coated with silica combined with a silane primer containing MDP. The phosphate ester groups of this silane bind to the surface oxides of the zirconia, and the methacrylate group makes covalent bonds with the resin matrix of the PANAVIA™ Veneer LC cement⁷.

In the present clinical cases, the KATANA™ Zirconia UTML veneers were abraded with silicon dioxide with the formula SiO2. As a primer, we chose CLEARFIL™ CERAMIC PRIMER PLUS (Kuraray Noritake Dental Inc.), because it contains the original MDP monomer, developed Kuraray Co., Ltd.⁸.

To clean the veneers before applying CLEARFIL™ CERAMIC PRIMER PLUS, KATANA™ Cleaner (Kuraray Noritake Dental Inc.) was used. The presence of saliva and residues from fittings can alter the interface with the resin cement, which presents a risk of bonding failure of Zirconia veneers⁹.

One of the most important challenges in this case was to be able to hide the greyish color of the implant abutment which was visible through the zirconia crown. To hide the gray of the abutment, a resin opaker was applied. These techniques combined with the PANAVIA™ Veneer LC white gave us an optimal result (figs. 9 and 10)¹⁰.

Fig. 9. Treatment outcome.

Fig. 10. New smile designed according to the individual desires of the patient.

CONCLUSION

KATANA™ Zirconia UTML veneers have better mechanical properties than conventional veneers, so that the zirconia veneers technique allows users to combine bridges, crowns and dental veneers without a noticeable difference in shade. It offers acceptable translucency and aesthetics according to our observation. The technique of bonding the zirconia veneers with PANAVIA™ Veneer LC combined with a tribochemical treatment and the application of MDP on the adhesion surfaces allowed for a secure bonding, while the dyschromia caused by the implant abutment was effectively concealed.

Dentist:

DR. BASSEM JAIDANE

Born in Sousse, Tunisia, on June 12, 1983, Dr. Bassem Jaidane obtained his Doctorate in Dental Medicine in 2010 at the Faculty of Monastir. He opened his own clinic in 2010, specializing in aesthetics and dental implants, as well as dental veneers. Omni-patrician and passionate about all areas of dentistry, he has also developed advanced knowledge in dental prosthetics: 3D design, ceramic layering, finishing and glazing of crowns, bridges and veneers…

Dr. Bassem Jaidane has therefore acquired a certain expertise on the different types of dental veneers, whether pressed ceramic veneers, machined veneers, layereded veneers with the cut-back technique and lumineers veneers, after having carried out numerous cases. in feldspathic and lithium disilicate veneers, Dr. Bassem Jaidane has become one of the pioneers of the technique of dental veneers on zirconia.

References

1. Restaurations esthétiques grâce à la technique du cut-back Par Fleur Nadal, Geoffrey Di Bacco, Julien Chesnot Publié le 01.06.2019. Paru dans L‘Information Dentaire n°23 – 12 juin 2019 (page 28-29).
2. Effects of ceramic layer thickness, cement color, and abutment tooth color on color reproduction of feldspathic veneers Christopher Igiel, Michael Weyhrauch, Barbara Mayer, Herbert Scheller, Karl Martin Lehmann PMID: 29379907 Int J Esthet Dent 2018;13(1):110-119.
3. Influence of Air-Particle Deposition Protocols on the Surface Topography and Adhesion of Resin Cement to Zirconia. Acta Odontol: Sarmento, H.R.; Campos, F.; Sousa, R.S.; Machado, J.P.B.; Souza, R.O.A.; Bottino, M.A.; Ozcan, M: Acta Odontol Scand . 2014 Jul;72(5):346-53.doi: 10.3109/00016357.2013.837958. Epub 2013 Oct 31.
4. Comparison of the Mechanical Properties of Translucent Zirconia and Lithium Disilicate:Kwon, S.J.; Lawson, N.C.; McLaren, E.E.; Nejat, A.H.; Burgess, J.O. J.Prosthet:: J Prosthet Dent . 2018 Jul;120(1):132-137. doi: 10.1016/j.prosdent.2017.08.004. Epub 2018 Jan 6.
5. The Success of Dental Veneers According To Preparation Design and Material Type:Yousef Alothman, Maryam Saleh Bamasoud: Open Access Maced J Med Sci. 2018 Dec 14;6(12):2402-408.doi:10.3889/oamjms.2018.353. eCollection 2018 Dec 20.
6. The Effect of Resin Bonding on Long-Term Success of High-Strength Ceramics: Blatz, M.B.; Vonderheide, M.; Conejo, J: J Dent Res 2018 Feb;97(2):132-139. doi: 10.1177/0022034517729134. Epub 2017 Sep 6.
7. Ultra-thin monolithic zirconia veneers: reality or future? Report of a clinical case and one-year follow-up: Rodrigo Othávio Assunção Souza, Fernanda Pinheiro Barbosa, Gabriela Monteiro de Araújo, Eduardo Miyashita, Marco Antonio Bottino, Renata Marques de Melo, and Yu Zhang :Oper Dent :2018 ;43(1) :3_11.doi :10.234/16-350-T.
8. Functional monomer impurity affects adhesive performance :Kumiko Yoshihara 1 , Noriyuki Nagaoka, Takumi Okihara , Manabu Kuroboshi, Satoshi Hayakawa, Yukinori Maruo, Goro Nishigawa, Jan De Munck, Yasuhiro Yoshida, Bart Van Meerbeek : Dent Mater : 2015 Dec;31(12):1493-501.doi: 10.1016/j.dental.2015.09.019. Epub 2015 Oct 28.
9. Effect of decontamination materials on bond strength of saliva-contaminated CAD/CAM resin block and dentin Kei Takahashi, Tomohiro Yoshiyama, Akihito Yokoyama, Yasushi Shimada, Masahiro Yoshiyama : Dent Mater J 2022 Jul 30;41(4):601-607. doi: 10.4012/dmj.2021-268. Epub 2022 Apr 13.
10. Masking ability of implant abutment substrates by using different ceramic restorative systems Pablo Machado Soares , Ana Carolina Cadore-Rodrigues , Maria Gabriela Packaeser , Atais Bacchi , Luiz Felipe Valandro , Gabriel Kalil Rocha Pereira , Marília Pivetta Rippe J Prosthet Dent 2022 Sep;128(3):496.e1-496.e8. doi: 10.1016/j.prosdent.2022.05.010. Epub 2022 Aug 16. Affiliations PMID: 35985853 DOI: 10.1016/j.prosdent.2022.05.010.

DENTAL ADVISOR Editor’s Choice and 2023 Preferred Product award recipient, quickly provides durable bond in a single procedure

CLEARFIL™ Universal Bond Quick has been named a 2023 Editor’s Choice by DENTAL ADVISOR, which evaluates dental products and equipment and publishes its findings annually. It has also received recognition as DENTAL ADVISOR’s Preferred Product this year in the category of Universal Bonding Agents. The 31 consultants who evaluated its application during 1,065 usages gave it the excellent overall rating of 98%.

CLEARFIL™ Universal Bond Quick is a single-bottle fluoride-releasing, universal adhesive with MDP monomer and amide monomer chemistry called rapid bond technology. This combination of the MDP monomer, which creates a strong chemical bond to hydroxyapatite, and newly developed hydrophilic amide monomer, which is highly hydrophilic, is responsible for fast chemical bonding and quick penetration into dental tissue. Because the amide monomer rapidly permeates dentin and enamel, it eliminates the need for long rubbing application of the adhesive into the dentin and reduces the wait time after application. After curing, the innovative amide monomer forms a moisture-resistant cross-linked polymer network.

As a result, the bonding is moisture-resistant and stable, with durable results. This method, which reduces application time without compromising bond strengths, sealing, or desensitizing, also reduces technique sensitivity.

A fast and versatile agent that bonds directly to dentin, enamel, metals, zirconia and lithium disilicate restorative materials, CLEARFIL™ Universal Bond Quick is suitable for bonding direct and indirect restoration and can be used for total-etch, selective-etch, or self-etch methods. When mixed with CLEARFIL™ DC Activator, CLEARFIL™ Universal Bond Quick becomes dual-cure and has universal use with both self- and dual-cured resin cements and core build-up resins. 

The practitioners evaluating the product commented on its ease in dispensing and placement, viscosity, suitability for all bonding procedures, and convenience. Among their remarks were: “Perfect viscosity. Ease of use and speed were great.” and “Great for replacement of silane to prime crowns for cementation with resin cement - will self-cure with the dual-cured resin.”

Honors such as Editor’s Choice that are conferred by US-based DENTAL ADVISOR were introduced to help busy practitioners make sense of the numerous new solutions indicated for less invasive techniques, standardized or simplified procedures, and better outcomes on a regular basis. DENTAL ADVISOR conducts its practice-based clinical evaluations and product performance tests shortly after product launch, and publishes results annually online to help potential users identify high-quality new dental materials and determine which among them are best suited to fulfill their individual requirements.