Reciprocal Angles Research Articles

Comparing the effect of Reciproc R25 rotary file system on the amount of apical extrusion of debris via using it with different reciprocal angles

Aim: To compare the amount of apically extruded debris using Reciproc (R25) file with different reciprocal angles.
 Methodology: In this research, 60 extracted mandibular premolars with a single root, a single canal, and a single apical foramen were used. Specimens, the working length of which was determined by a stainless steel 10-K file, were randomly distributed into three experimental groups (n = 20) as follows: Group 1 150° counterclockwise (CCW)-30° clockwise (CW); Group 2 180° CCW-60° CW; and Group 3 210° CCW-90° CW. For the irrigation, 10 mL of distilled water was administered via syringe pump. The extruded debris was collected into Eppendorf tubes tared in advance. The distribution of data was analyzed using a Shapiro-Wilk test. A Kruskal-Wallis H test was used for statistical analysis. The null hypothesis is no significant difference between the groups in terms of the amount of apical extrusion of debris.
 Results: There was no statistically significant difference between the groups with regard to amount of apical extrusion of debris (p>0.05). Nevertheless, the highest average amount of extrusion of debris was detected in group 1, and the lowest in group 3.
 Conclusion: According to the results of this study, different reciprocal angles during chemomechanical preparation has no significant effect on the amount of apical extrusion of debris.
 
 How to cite this article: Çelik N, Kaya S, Adıgüzel Ö. Comparing the effect of Reciproc R25 rotary file system on the amount of apical extrusion of debris via using it with different reciprocal angles. Int Dent Res 2021;11(Suppl.1):63-6. https://doi.org/10.5577/intdentres.2021.vol11.suppl1.10
 
 Linguistic Revision: The English in this manuscript has been checked by at least two professional editors, both native speakers of English.

Baumann's confusing legacy

Dr Ernst Baumann has been credited with describing an angle that can be measured from radiographs taken of children's elbows. This article presents three variations in the definition of this angle that we found in the orthopaedic literature. Variation I is the angle between the long axis of the humerus and a line through the physis of the lateral condyle of the distal humerus. Variation II is the angle between the perpendicular to the long axis of the humerus and a line through the physis of the lateral condyle. Variation III is the angle between the line through the physis of the lateral condyle and a line connecting a point on the edge of the trochlea to a point at the lateral limit of the physis of the lateral condyle. By reading translations of two of Baumann's own articles, we have realised that he used variation I when assessing the radiographs. He did, however, believe that the reciprocal angle, variation II equalled the carrying angle of the elbow and this can be demonstrated by Fig. 1, which has been taken from an article that was published in 1929. The relationship between this angle and the carrying angle has since been proven to be more complex than Baumann believed. We recommend that a descriptive term such as the ‘shaft-physeal’ angle would cause less confusion and variation in the definition of this angle.