In vitro comparison of peracetic acid and autoclave sterilization in the corrosion of orthodontic pliers: a pilot study

ABSTRACT Introduction: The most currently recommended method for sterilization of orthodontic pliers is the autoclave, while peracetic acid has also been shown to be effective in the chemical sterilization process. Objective: This study sought to compare the corrosive effects of peracetic acid and autoclave sterilization process of orthodontic pliers. Methods: Four active tungsten carbide (WC) stainless steel tie-cutting pliers from the manufacturers Quinelato (Rio Claro, SP, Brazil) and ICE (Cajamar, SP, Brazil) were selected. The active ends of the pliers were sectioned, and six active tips were obtained and distributed into the following groups: 1) control group (no sterilization); 2) AC group (two active pliers tips submitted to 100 autoclave sterilization cycles); and 3) AP group (two active pliers tips submitted to 100 cycles of sterilization by immersion in 2% peracetic acid solution for 30 minutes). Results: Chemical analysis using X-ray dispersive energy spectroscopy showed that after autoclave sterilization, only the ICE pliers presented oxidation corrosion (Δ[O] = +24.5%; Δ[Fe] = +5.8%; Δ[WC] = -1.9%). In comparison, following peracetic acid sterilization, both manufacturers ICE (Δ[O] = +1.8%; Δ[Fe] = +18.0%; Δ[WC] = -1.1%) and Quinelato (Δ[O] = +5.3%; Δ[Fe] = -10.4%; Δ[WC] = -15.2%) showed corrosion. The morphological analysis revealed that peracetic acid caused a pitting and localized corrosion in both brands, while the autoclave caused uniform surface corrosion on the ICE pliers. Conclusion: Autoclave application was the sterilization method that generated less corrosive damage to the orthodontic cutting pliers, when compared to the immersion in 2% peracetic acid.

摘要
引言：目前临床最推荐的正畸钳灭菌方式为高压蒸汽灭菌法，而过氧乙酸也已被证实可应用于化学灭菌流程。
目的：本研究旨在对比过氧乙酸与高压蒸汽灭菌法对正畸钳的腐蚀影响。
方法：选取巴西圣保罗州里奥克拉鲁市Quinelato公司及卡雅马尔市ICE公司生产的4支工作端为碳化钨（tungsten carbide, WC）不锈钢切断正畸钳。将钳具工作端切段，获得6个工作钳头并分为以下三组：1）对照组（未进行灭菌处理）；2）AC组：2个工作钳头经100次高压蒸汽灭菌循环；3）AP组：2个工作钳头经100次2%过氧乙酸溶液浸泡灭菌，每次浸泡时长30分钟。
结果：采用X射线能量色散光谱法（X-ray dispersive energy spectroscopy）进行化学分析显示：经高压蒸汽灭菌后，仅ICE品牌钳头出现氧化腐蚀（Δ[O] = +24.5%；Δ[Fe] = +5.8%；Δ[WC] = -1.9%）。相较而言，经过氧乙酸灭菌后，ICE（Δ[O] = +1.8%；Δ[Fe] = +18.0%；Δ[WC] = -1.1%）与Quinelato（Δ[O] = +5.3%；Δ[Fe] = -10.4%；Δ[WC] = -15.2%）两个品牌的钳头均出现腐蚀。形貌分析结果显示，过氧乙酸会导致两个品牌的钳头出现点蚀与局部腐蚀，而高压蒸汽灭菌仅会使ICE品牌钳头出现均匀表面腐蚀。
结论：与2%过氧乙酸浸泡灭菌法相比，高压蒸汽灭菌法对正畸切断钳的腐蚀损伤更小。