A new adhesive technology for all-ceramics

A new adhesive technology for all-ceramics

R.Janda,J.-F.Roulet *,M.Wulf,H.-J.Tiller

School of Dental Medicine,Humboldt-University Berlin (Charite

´),D-13353Berlin,Germany Received 13June 2001;revised 12March 2002;accepted 11July 2002

Abstract

Objectives .Evaluation of a new surface treatment method to obtain a good bond strength between a luting composite and several ceramics.

Methods .Specimen preparation and test procedure were done according to ISO 10477Amendment 1.The surfaces of Empress II,InCeram-Alumina,InCeram-Zirconia and Frialit (ZrO 2)were ground under water-cooling with 400grit grinding paper,afterwards polished with 800grit and air-dried.Each ceramic material investigated was divided into three groups of 10specimens each.Group 1was flame-treated with the PyrosilPen for 2.5s,group 2for 5s and group 3for 10s/cm 2.After the flame treatment,a methacryl silane was applied followed by a luting composite.Prior to measuring shear bond strength,the specimens were thermocycled 5000times in a water-bath between þ5and þ558C.Furthermore,SEM-and Fourier-transform infrared spectrophotometer (FT-IR)-investigations were done.As a control,Empress II etched and silaned was used.

Results .Shear bond strength measurements indicated that the optimal treatment time was 5s/cm 2.Regarding this time the following bond strength values between the luting composite and the various ceramics were obtained:Empress II 23(5)MPa,InCeram-Alumina 23(5)MPa,InCeram-Zirconia 13(8)MPa,and Frialit 16(6)MPa.The control achieved 27(6)MPa.On all surfaces of the flamed specimens Si could be detected by FT-IR.

Significance .The PyrosilPen-Technology is an easy and effective method for surface-treating silicate,aluminum oxide and zirconium oxide ceramics to obtain good bonding to luting composites.

q 2003Academy of Dental Materials.Published by Elsevier Science Ltd.All rights reserved.

Keywords:Ceramic;Dental;Adhesion;Silane;Zirconium oxide;Aluminum oxide;Silicon oxide;Composite

1.Introduction

For more than roughly 15years it has been a well-known fact that all-ceramics should be inserted using adhesive techniques [1–20].Regarding feldspathic or more precisely silicate ceramics (SiO 2),hydrofluoric acid (H 2F 2)-etching followed by application of 3-methacryloyl oxypropyl trimethoxy silane is a common and clinically well-proven procedure.The conditioned ceramic surface can interact micro-mechanically as well as chemically with the luting composite.The conditioning process is complicated and time consuming as well as awkward and involved.It should also be considered that hydrofluoric acid is a toxic chemical which causes,in the case of skin contact,severe damage.A simplified,safe and less time consuming method would be a desirable improvement.

In recent years,new high performance ceramics such as aluminum oxide and zirconium oxide ceramics are more and more commonly used in restorative dentistry.Dental applications of these materials are all-ceramic crowns and bridges [21–30]as well as various all-ceramic core and post systems [31–34].Their physical,clinical and esthetic properties are convincing so that their use will increase in the future.Although adhesion between the luting composite and alumina or zirconia ceramics is desirable,for many clinical applications only limited data can be found in the literature.However,it is quite clear,based on chemical knowledge,that hydrofluoric acid etching is only possible with SiO 2-based ceramics or glasses according to the reaction equation

6H 2F 2þ2SiO 2!2H 2SiF 6þ4H 2O

ð1Þ

This reaction certainly cannot occur regarding alumina or zirconia.Therefore,other bonding techniques are required in order to lute these materials adhesively.The following

0109-5641/03/$-see front matter q 2003Academy of Dental Materials.Published by Elsevier Science Ltd.All rights reserved.

doi:10.1016/S0109-5641(02)00106-9

Dental Materials 19(2003)567–573

/locate/dental

*Corresponding author.Tel.:þ49-30-450-562-672;fax:þ49-30-450-562-961.

E-mail address:jfroulet@ (J.-F.Roulet).