INFLUÊNCIA DA MODIFICAÇÃO DA BASE DE COLAGEM E DA CONTAMINAÇÃO SALIVAR NA RESISTÊNCIA DE UNIÃO DE TUBOS ORTODÔNTICOS COLADOS AO ESMALTE HUMANO

Germano Brandão,Mayara Paim Patel,Dimorvan Bordin,Ana Carla Raphaelli Nahás-Scocate,Marina Guimarães Roscoe,Liliana Ávila Maltagliati,Murilo Matias

doi:10.46311/2318-0579.58.euj3657

Abstract

The objective of this in vitro study was to assess and compare the shear bond strength of conventional and modified orthodontic tubes bonded to the surface of dry and saliva-contaminated enamel. The sample consisted of 40 human teeth, which were randomly divided into four groups according to attachment base and presence or absence of saliva contamination as follows: Group CB, conventional orthodontic tubes without salivary contamination; Group CB-S, conventional orthodontic tubes with salivary contamination; Groups BM, orthodontic tubes modified by welding a metal mesh to their base without salivary contamination; and Group BM-S, modified orthodontic tubes with salivary contamination. Shear bond strength test was performed in a universal testing machine and analysis of the adhesive remnant index (ARI) by optical microscopy. Two-way ANOVA was used, followed by Tukey’s test at a statistical significance level of 5%. The ARI results were analysed descriptively. There was statistically significant difference between the groups regarding the shear bond strength values, with conventional tubes presenting significantly higher values (P < 0.05). In addition, the presence of salivary contamination interfered negatively with the behaviour of conventional tubes only (P < 0.05). Shear bond strength was not improved by increasing the area of the orthodontic tubes. Moreover, salivary contamination influenced negatively the SBS values, but only when conventional tubes were used.

Highlights

Orthodontic bands have been used for years and their mechanical advantages in terms of strength and force gradients are widely known (BANKS; MACFARLANE, 2007)
This scenario has encouraged the replacement of cemented bands with directly bonded orthodontic tubes (ALEXANDER, 1991; BOYD; BAUMRIND, 1992; SCOUGALL-VILCHIS; OHASHI; YAMAMOTO, 2009; MELO et al, 2012)
Some advantages cited by Murray, Millett and Cronin (2012) are clearly evidenced, such as efficient operative time (TALPUR et al, 2012), easy detection of carious lesions due to better visibility of enamel (ZACHRISSON, 1976), lower number of visits and less risk of contamination (BOYD; BAUMRIND, 1992; BANKS; MACFARLANE, 2007), more comfort for the patient and less risk of demineralisation (BANKS; MACFARLANE, 2007), easy examination and need for less space in the arch for orthodontic treatment and possible restorative interventions (ALEXANDER, 1991; BOYD; BAUMRIND, 1992; MELO et al, 2012)

Summary

Introduction

Orthodontic bands have been used for years and their mechanical advantages in terms of strength and force gradients are widely known (BANKS; MACFARLANE, 2007). According to Gange (2015), orthodontic bands may cause undesirable periodontal problems when placed on interproximal facets, such as gingival trauma and pain on placement, including a higher risk of bacteremia (ERVERDI et al, 2001). This scenario has encouraged the replacement of cemented bands with directly bonded orthodontic tubes (ALEXANDER, 1991; BOYD; BAUMRIND, 1992; SCOUGALL-VILCHIS; OHASHI; YAMAMOTO, 2009; MELO et al, 2012). This value is empirically determined, it is clinically accepted as a sufficient force for orthodontic brackets resist the shearing forces of mastication (SCOUGALL-VILCHIS; OHASHI; YAMAMOTO, 2009)

Objectives

Methods

Results