고농도 불소와 미백제가 교정용 와이어와 브라켓 본딩력에 손상을 준다는 논문

J Orthod Sci. 2016 Oct-Dec; 5(4): 121–126.

doi: 10.4103/2278-0203.192114

PMCID: PMC5084473

PMID: 27843886

Fluoride influences nickel-titanium orthodontic wires' surface texture and friction resistance

Objectives:

The aim of this study was to investigate the effects exerted by the acidulated fluoride gel on stainless steel and nickel-titanium (Ni-Ti) orthodontic wires.

Materials and Methods:

Sixty stainless steel and Ni-Ti orthodontic archwires were distributed into forty archwires used for in vitro study and twenty for in situ study. Fluoride was applied for 1 h in the in vitro experiment while it was applied for 5 min in the in situ experiment. The friction resistance of all wires with ceramic brackets before/after topical fluoride application was measured using a universal testing machine at 1 min intervals of moving wire. Moreover, surface properties of the tested wires before/after fluoride application and before/after friction test were examined by a scanning electron microscope (SEM). Dunnett's t-test was used to compare frictional resistance of as-received stainless steel wires and Ni-Ti wires to the wires treated by fluoride in vitro and in situ (P < 0.05). Two-way ANOVA was used to compare the effect of fluoride application and type of wire on friction resistance in vitro and in situ (P < 0.05).

Results:

Ni-Ti wires recorded significantly high friction resistance after fluoride application when compared to stainless steel wires in vitro, P < 0.05. Fluoride application did not significantly affect the friction resistance of the tested wires in situ, P < 0.05. SEM observation revealed deterioration of the surface texture of the Ni-Ti wires after fluoride application in vitro and in situ.

Conclusions:

The in vitro fluoride application caused an increase in friction resistance of Ni-Ti wires when compared to stainless steel wires. In vitro and in situ fluoride application caused deterioration in surface properties of Ni-Ti wires.

Key words: Fluoride, friction resistance, orthodontics, prophylaxis, surfaces

The effect of carbamide peroxide bleach on the tensile bond strength of ceramic brackets: An in vitro study

Abstract

Recent advances in cosmetic dentistry have led to the development of a variety of new products and techniques including vital bleaching and ceramic brackets. Therefore this study was conducted to see whether the use of an at-home carbamide peroxide bleaching agent before bonding affected the tensile bond strength of a precoated ceramic orthodontic bracket. Sixty extracted human premolar teeth were randomly separated into three groups of 20. Group 1 was a control group that was etched and bonded in the usual manner. Group 2 was immersed in a carbamide peroxide home bleaching agent for 72 hours before pumicing and bonding. Group 3 was also bleached for 72 hours but was immersed in distilled water for 1 week before bonding. The results indicated that recently bleached teeth have significantly reduced bond strength values when compared with both groups 1 and 3. We suggest that if a patient is using a tooth whitening product, that they discontinue its use at least 1 week before the bonding of orthodontic attachments. (AM J ORTHOD DENTOFAC ORTHOP 1994;106:371-5.)