Influence of autoclave sterilization procedures on the cyclic fatigue resistance of heat-treated nickel-titanium instruments: a systematic review

Abstract

Objectives: This systematic review evaluated the influence of autoclave sterilization procedures on the cyclic fatigue resistance of heat-treated nickel-titanium (NiTi) instruments. Results: From 203 abstracts, a total of 10 articles matched the eligible criteria. After reading the full articles, 2 were excluded because of the absence of the heat-treated instruments in the experimental design and 3 due to the lack of a control group using heat-treated instruments without autoclave sterilization. From the 5 included studies, 1 presented a low risk of bias, 3 presented moderate and 1 high risk. It was observed heterogeneous findings in the included studies, with autoclave sterilization cycles increasing, decreasing or not affecting the cyclic fatigue life of heat-treated NiTi instruments. However, the retrieved studies evaluating the cyclic fatigue resistance of endodontic instruments presented different protocols and assessing outcomes, this variability makes the findings less comparable within and also between groups and preclude the establishment of an unbiased scientific evidence base. Conclusions: Considering the little scientific evidence and considerable risk of bias, it is still possible to conclude that autoclave sterilization procedures appear to influence the cyclic fatigue resistance of heat-treated NiTi instruments.

Effect of body temperature on the cyclic fatigue resistance of the nickel”titanium endodontic instruments: A systematic review and meta-analysis of in vitro studies

“…The methodological quality of the included research was determined using an adaption of a prior systematic review that included in vitro investigations. [ 13 ] The domains listed below were used: (1) sample standardization, (2) sample size calculation, (3) sample randomization, (4) single-operator, (5) blinding, (6) testing model standardization, and (7) appropriate statistical analysis. The domains were categorized as “+” to specify a low risk of bias (RoB) and “-” to indicate a high RoB.…”

Effect of Autoclaving Cycles on the Cyclic Fatigue Resistance of Race and Race Evo Nickel-Titanium Endodontic Rotary Files: An In Vitro Study

“…In order to standardize experimental parameters, files were tested in a canal grooved within a metal block without any back-and-forth movement. Although this static model does not reproduce clinical situations, nor does it replicate the extended distribution of stresses associated with rhythmic movement, it remains the preferred model for evaluating cyclic fatigue used in previous studies [8,9,13,14]. That said, the results obtained in this study may not be identically reproducible in clinical settings.…”

“…Because thermal treatment has a significant influence on the mechanical properties of NiTi, the additional heat that files are subjected to during autoclaving procedures may have an effect on the mechanical qualities of these instruments. A recent systematic review [9] reported that the cyclic fatigue resistance of heat-treated NiTi instruments seems to be influenced by autoclave sterilization methods. According to Zhao et al [6], although thermal-treated HyFlex CM, Twisted File, and K3XF instruments were found to be more resistant to cyclic fatigue failure than Race and K3 instruments, autoclaved HyFlex CM and K3XF instruments were more resistant to cyclic fatigue than Twisted File.…”

Influence of sterilization procedures on the physical and mechanical properties of rotating endodontic instruments: a systematic review and network meta-analysis

“…However, there is excessive diversity in the studies, such as different apparatuses to measure cyclic fatigue, different angles of curvature of the artificial canals with which the cyclic fatigue was measured, the heterogeneity of instruments and different numbers of sterilization cycles. These differences can lead to results with a high heterogeneity index, as also indicated by a recent systematic review conducted by Silva et al [87].…”

“…First outcome: Khabiri et The entire selection and screening procedure, as described in Table 2 (Ref. [7,40,41,[87][88][89][90]), is presented in the flowchart in Fig. 1.…”