Influence of laser deproteinization of acid-etched dentin on marginal microleakage of class V composite restoration

Shahin Kasraei,Sogol Nejadkarimi,Mona Malek,Mahsa Mohammadi

doi:10.20396/bjos.v20i00.8660525

Abstract

Aim: Recent reports indicate that deproteinization of acid-etched dentin surface can extend penetration depth of adhesive agents. The main goal of the present research was to investigate the deproteinization effect of Nd:YAG and diode 940 lasers on acid-etched dentin and microleakage grade in class V composite restorations. Methods: 36 extracted human premolar teeth were selected to make standard buccal and lingual class V cavities. These samples were randomly split into three sub-groups: 1.Control group, in which composite was applied for restoration after etch and bonding process without deproteinization; 2.Nd:YAG laser group, in which the teeth were deproteinized with Nd:YAG laser after etching and painting internal surfaces of cavities with Van Geison stain and then composite restorations applied just as control group; 3.Diode laser group, in which the process was similar to Nd:YAG laser group, but instead, diode 940 laser was irradiated. The teeth were bisected into two equal longitudinal buccal and lingual halves. Marginal microleakage of samples was scored by using a stereomicroscope. Kruskal- Wallis, Mann-Whitney U and Fisher’s statistical tests were employed for analysis of the obtained data. Results: A significant reduction in marginal microleakage was observed for both groups treated with laser (Nd:YAG and diode 940)compared to control (p=0.001 & p=0.047). There was no significant difference in marginal microleakage between Nd:YAG laser and diode 940groups (P = 0.333). Conclusion: Nd:YAG and diode 940 laser deproteinization of acid-etched dentin decreased the marginal microleakage of in-vitro class V resin composite restorations.

Highlights

There have been many studies to improve the quality of composite restorations bonding and decrease microleakage until now
36 extracted human premolar teeth were selected to make standard buccal and lingual class V cavities. These samples were randomly split into three sub-groups: 1.Control group, in which composite was applied for restoration after etch and bonding process without deproteinization; 2.Nd:YAG laser group, in which the teeth were deproteinized with Nd:YAG laser after etching and painting internal surfaces of cavities with Van Geison stain and composite restorations applied just as control group; 3.Diode laser group, in which the process was similar to Nd:YAG laser group, but instead, diode 940 laser was irradiated
Decreasing or removing the collagen network in resin-dentin interface can improve the strength of bond and reduce marginal microleakage[2,22,23,24]

Summary

Introduction

There have been many studies to improve the quality of composite restorations bonding and decrease microleakage until now Many techniques such as oblique layering technique, using lining materials, different curing modes and pre-polymerized composite inserts have been tried on adherend surface to reduce this microleakage, there exists no method to eliminate the microleakage of gingival margin completely yet[1,2,3,4]. One of the recommended method for adherent surface to reduce the marginal microleakage complication is to eliminate or decrease the collagen network in acid-etched dentin and composite interface by the use of different materials such as enzymes, proteolytic agents[3,4,5,6] or lasers[2,5,7]. Collagen network has the potential to be painted by special dyes which can differentiate the collagen network and enhance the effectiveness of collagen removal from acid-etched dentin surface without any effect on mineralized tissue[2,3,8,9]

Objectives

Methods

Results

Conclusion