May the flexural strength of ceramics be influenced by salivary pH?

Caroline Cotes,Mariana Camillo,Vanessa Cruz Macedo,Estevao Kimpara,Bruna Lara,Carolina Martinelli,Rodrigo Carvalho

doi:10.14295/bds.2013.v16i2.893

Caroline Cotes, Mariana Camillo + Show 5 more

Open Access

https://doi.org/10.14295/bds.2013.v16i2.893

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Abstract

Objective. This study purpose was compare the three-point flexural strengths of 50 feldspathic ceramic after storage in artificial saliva. Material and methods. The bars were luted with resin cement and subjected to storage in artificial saliva of different pHs. Results. The values of flexural strength were significantly higher for the bars stored in distilled water, at neutral and basic pH, when compared with the results for the bars stored in acidic pH and in acid/basic pH. Conclusions. Storage for 30 days in artificial saliva at acidic pH, or alternating between acidic and basic pH, can reduce the mechanical properties of ceramics.

Highlights

C eramics are widely used in dentistry because of their excellent properties
The mechanical properties of feldspathic ceramics were affected by storage in acidic artificial saliva for 30 days and 15 days with alternation
Shorter storage in acid pH did not cause surface changes [4], but after 7 days of acid immersion, surface deterioration could be observed[1,2], with numerous porosities and small cracks covering the feldspathic ceramic surface[2]. This surface alteration could reduce the ceramic’s flexural strength, the crack growth rates of existing flaws were similar over time, regardless of the salivary pH[3]

Summary

Introduction

C eramics are widely used in dentistry because of their excellent properties. Chemical durability is one of the requirements for their intra-oral use, since dental prostheses must be resistant to degradation in a wide range of variable pH solutions. Ceramics are considered to be the most inert of all dental materials used for restorations[1], in reality, some ceramics are not chemically inert, even in a neutral aqueous environment[2], and storage in acid or basic pH can result in degradation of their flexural strength[1,3]. Few studies have been performed to measure the effects of chemical ‘attack’ on ceramics over the entire pH range[1], and no study has evaluated the effects of pH changes on their mechanical properties. The aim of this study was to evaluate the flexural strength of a feldspathic ceramic stored at different pHs. Braz Dent Sci 2013 Abr/Jun;16(2)

Results

Conclusion