Evaluation of apical foramen deformation produced by manual and mechanized patency maneuvers

Achieving apical foramen patency through surgical maneuvers during the biomechanical preparation of root canals is a goal sought by several schools. The aim of this study was to evaluate the deformation of the foramen as a result of using stainless steel hand files and nickeltitanium rotary instruments for achieving patency. Forty recently extracted dental roots with single canals were calibrated to a length of 18 mm and mounted on acrylic blocks to enable study maneuvers. Each foramen was observed and mapped using SEM (Phillips high vacuum) at x 100, using Golden Ratio software (Softonic). Endodontic surgical preparation was subsequently performed on all samples to 1 mm from the foramen using the Protaper rotary system up to instrument F3. The samples were then divided into two groups of twenty for apical patency maneuvers: Group A (manual patency) on which stainless steel Flexofile (MailleferSuiza) hand files gauge .10 were used, and Group B (rotary patency) on which NiTi Pathfile (DentsplyMailleferSuiza) rotary instruments gauge .13 at 150 rpm, were used. The foramina were examined again using SEM, measured, mapped and compared with the previous images. A scale was established to evaluate the observations. Results were analyzed using the Mann Whitney test, which showed no significant difference between groups (p=0.110). It is concluded that under the conditions of this study, surgical apical patency maneuvers using stainless steel manual files or nickel titanium rotary instruments produced different degrees of foramen deformation, with no significant difference between methods.