Ask in Person: You’re Less Persuasive Than You Think Over Email

Research has found people underestimate the likelihood strangers will comply with their direct requests (Bohns, 2016; Flynn & Lake, 2008). Here we argue this “underestimation- of-compliance effect” may be limited to requests made face-to-face. We find when making direct requests over email, requesters instead overestimate compliance. In two studies, participants asked strangers to comply with requests either face-to-face or over email. Before making these requests, requesters estimated the number of people they expected to say “yes”. While requesters underestimated compliance in face-to-face contexts, replicating previous research, they overestimated compliance in email contexts. Analyses of several theorized mechanisms for this finding suggest that requesters, anchored on their own perspectives, fail to appreciate the suspicion, and resulting lack of empathy, with which targets view email requests from strangers. Given the prevalence of email and text-based communication, this is an extremely important moderator of the underestimation-of-compliance effect.Bohns21_Ask_in_person.pdf: 205 downloads, before Oct. 1, 2020

Ask in Person: You’re Less Persuasive Than You Think Over Email

Research has found people underestimate the likelihood strangers will comply with their direct requests (Bohns, 2016; Flynn & Lake, 2008). Here we argue this “underestimation- of-compliance effect” may be limited to requests made face-to-face. We find when making direct requests over email, requesters instead overestimate compliance. In two studies, participants asked strangers to comply with requests either face-to-face or over email. Before making these requests, requesters estimated the number of people they expected to say “yes”. While requesters underestimated compliance in face-to-face contexts, replicating previous research, they overestimated compliance in email contexts. Analyses of several theorized mechanisms for this finding suggest that requesters, anchored on their own perspectives, fail to appreciate the suspicion, and resulting lack of empathy, with which targets view email requests from strangers. Given the prevalence of email and text-based communication, this is an extremely important moderator of the underestimation-of-compliance effect.Bohns21_Ask_in_person.pdf: 205 downloads, before Oct. 1, 2020

Comparison of WaveOne and ProTaper Universal Preparation Systems in the Amount of Smear Layer/Debris Production: an in-vitro SEM Study

Background and Aim: Debris and the smear layer that remain after root canal preparations may result in failure of root canal therapies. The aim of this study was to compare the smear layer formation and the amount of residual debris following the use of WaveOne and ProTaper rotary files in mesiobuccal root canals of upper first molars by scanning electron microscopy (SEM). Materials and Methods: In this experimental study, 34 mesiobuccal root canals of human maxillary first molars with 20°-40° curvatures (according to Schneider technique) were randomly distributed in two experimental groups (15 each) and two control groups. The canals in test groups were instrumented according to the manufacturers’ instructions. Five ml of 5.25% sodium hypochlorite (NaOCl) and 5 ml of normal saline were used as irrigants. The roots were split longitudinally, and apical, middle, and coronal radicular sections were randomly scanned by an SEM at ×1000 magnification. Two endodontists scored the data according to Schäfer and Schlingemann scoring system. Data of the amount of debris and smear layer were separately analyzed by Kruskal-Wallis test. Results: Although there was a slight difference in mean scores between the two groups (3.28 for WaveOne and 3.6 for ProTaper), no significant differences in debris amount were noted. The overall mean smear layer formation was not significantly different between the two groups (4.11 for WaveOne and 3.95 for ProTaper). Conclusion: There was no significant difference in remaining debris and smear layer in coronal, middle, and apical parts of root canals. However, ProTaper system appeared to produce less debris during preparation

Centering Ability of F6 SkyTaper and RaCe Rotary Files: A Cone-Beam Computed Tomography Study

Background and Aim: Maintaining the original shape and path of the canal is among the most important criteria for optimal root canal preparation. The aim of this study was to compare the centering ability of F6 SkyTaper and RaCe rotary files in mesiobuccal canals of mandibular molars.   Materials and Methods: In this experimental study, 30 mesiobuccal canals of extracted human mandibular molars with 25-30-degree curvature were randomly divided into two experimental groups (n=15) of RaCe and F6 SkyTaper. After mounting of the teeth in a putty mold, the distance between the canal walls and the outer surface of the roots in mesial and distal aspects was measured. The measurements were made at 1, 3 and 7 mm from the apex. Initial glide path in the canals was achieved using a # 15 K-file. Then, the canals in group A were prepared by RaCe rotary file #25/6% while the canals in group B were prepared by F6 Sky Taper rotary file #25/6%. Measurements were repeated and the difference between the two measurements was calculated and compared with the Mann-Whitney U test. Results: The mean centering ability was 0.72 ± 0.62 in the RaCe group and 0.95 ± 1.39 in F6 SkyTaper group. the centrality was better in F6 SkyTaper group (it was closer to 1) but the difference was not statistically significant (P=0.4). Conclusion: Both RaCe and F6 SkyTaper rotary systems partially offset the centrality of the root canal system

Effect of 2% Lidocaine and 1:80000 Epinephrine on Heart Rate and Blood Oxygen Saturation During Inferior Alveolar Nerve Block and Gow-Gates Block:A Clinical Trial

Background and Aim: The Gow-Gates (GG) block and the inferior alveolar nerve block (IANB) can be used interchangeably for anesthetizing mandibular molars. The aim of this study was to compare these two injections in root canal therapy of mandibular molars with regard to heart rate (HR) and blood oxygen saturation (BOS) changes. Materials and Methods: Thirty patients between the ages of 18-70 years having mandibular molars on both sides of their jaw and in need of root canal therapy were recruited after signing a consent form. The patients' HR and BOS were measured 5 minutes before and immediately, 2, 5, 10, 15, and 20 minutes after injection by using a pulse oximeter. Paired t-test and Friedman test were used for statistical analysis of the data. Results: This study was done on 30 patients (60 teeth). The results of HR and BOS showed no significant differences between the two injection techniques (P=0.6 and 0.7, respectively). Also, HR and BOS in each group were not significantly changed during the follow-ups (P=0.7 and 0.6, respectively). Conclusion: According to the results, IANB and GG block by using 2% lidocaine and 1:80000 epinephrine had no significant different effects on HR and BOS

The Effect of Autoclave Sterilization on the Fracture Resistance of ProTaper Rotary Files

Background and aim: The purpose of this study was to evaluate the effect of autoclave sterilization on the fracture rate of ProTaper instruments (ex vivo). Materials and methods: One hundred shaping and finishing ProTaper instruments were used in a crown – down technique for cleaning and shaping the mesial canals of extracted mandibular molars using 5.25% NaOCl for irrigation. In the experimental group, 50 files were steam autoclaved before each use. In the control group, the files were not exposed to the sterilization process. The working time was reported for each file. Independent t- test was employed to evaluate the statistical significance of the measured values. Results: The instruments that underwent the sterilization processes did not show any statistically significant differences in comparison with those of the control group. Conclusions: The results of this study showed that sterilization in autoclave in the presence of NaOCl did not lead to a decrease in survival time of the files