Friction and Debonding Strength of the TP Orthodontics InVu Ceramic Brackets: A Comparative Study"

Abstract

With the steady increase of the number of adults undergoing orthodontic treatment, there has been a corresponding increase in demand for more esthetic orthodontic appliances. The purpose of this study is to determine the friction value of esthetic wires compared to conventional stainless steel wire, the bending capacity, and the relationship between the coating layer's composition and the friction value, in comparison to the conventional steel wires using different types of ceramic brackets as well as a metal bracket as a control group.

Materials and methods: Four types of brackets (Clarity 3M Unitek, GAC, TP, GAC metal) were coupled with ten different types of arch wires: 0.0016" round conventional stainless steel,0.0016" round (Denturum) stainless steel,0.0016" round (Ortho.technology) stainless steel, 0.0016" round (G&H) stainless steel, 0.0016"x 0.0022" rectangular conventional stainless steel,0.0016"x0.0022"rectangular (Denturum) stainless steel, 0.0016"x0.0022" rectangular (Ortho technology)stainless steel, 0.0016"x0.0022" rectangular (G&H) stainless steel, 0.0018"x0.0022" rectangular(G&H) stainless, and 0.0018"x 0.0022" rectangular (Ortho technology) stainless steel . After testing, penetration through the coating layer was observed in all specimens, and the frictional and binding coefficients were still within the limits outlined by conventional orthodontic wire bracket couples.

A friction test,and a bending test at different angles was performed on various wires and brackets. EDS was used to determine the elemental composition of the coating layer and the wires. The wires and brackets were measured by optical microscopy. In the dry state and regardless of slot size, the mean kinetic coefficients of friction were smallest for a ceramic bracket with glazed slot; all stainless steel combinations and the ceramic bracket with metal slot had the largest values with 0.0018"x0.0022 "combinations.

Objectives: the aim of this study was to evaluate the frictional force between orthodontic brackets and archwires. Using ceramic brackets with metal reinforced slot, and stainless steel brackets in combination with traditional stainless steel, and different types of tooth colored wires.

Results: there is no significant difference between the friction values of the different wires, however Student t-test demonstrated significant difference in friction value for the 0.0018"x0.0022" wires, between the Ortho technology and G&H wires, but there was no difference between the other groups in the friction test. For the bending test, increasing the bending angle (the angle between the wire and the bracket) increased the friction force value.

Table of Contents

Abstract2

Friction and Debonding Strength of the TP Orthodontics InVu Ceramic Brackets: A Comparative Study5

Introduction5

Literature Review5

History of Orthodontic Archwires9

Esthetic wires development18

Classification of orthodontic arch wires22

Materials and Methods24

METHODS25

Scanning electron microscopy (SEM)26

Coefficient of Friction29

Limitations and Clinical implications35

Suggestions for future research35

References43

Friction and Debonding Strength of the TP Orthodontics InVu Ceramic Brackets: A Comparative Study

Introduction

So called sliding mechanics is a common approach used in the “distalization” of teeth to obtain increased arch length. Consequently, relative motion occurs between the bracket and archwire with attendant frictional resistance at their interfaces. Many studies have been conducted to evaluate the principle factors that may influence frictional resistance. These have been identified as:

(1) Relative bracket/archwire clearance;

(2) Archwire size as related to stiffness;

(3) ...