Constructions of the scale of difficulty in the extraction of impacted mandibular third molars by using Delphi method / 北京大学学报(医学版)

OBJECTIVE@#To evaluate the relevant indicators affecting difficulty in the extraction of impacted mandibular third molars and score difficulty of different operation and risk indicators, so as to build an intuitive and accurate scale to help operators make more accurate analysis and prediction of difficulty before the operation.@*METHODS@#Based on literature and the clinical review, the difficulty indicators of tooth extraction were summarized. Firstly, 10 doctors from Peking University School and Hospital of Stomatology who had been engaged in alveolar surgery for a long time established an expert nominal group, and then rated whether the summarized indicators needed to be retained in the form of face-to-face questionnaires. A level 1 and 2 item frame for evaluating difficulty in the tooth extraction was formed after discussion; Then Delphi method was used to send a questionnaire to 30 experts by e-mail. After two rounds of scoring and modification, the scale of difficulty in the extraction of impacted mandibular third molars was formed.@*RESULTS@#The recycling rate of two rounds of questionnaires was 100.0%, which showed that the experts were very enthusiastic about the study; The authority coefficients (Cr) of the two rounds of Delphi expert consultation were both 0.92, which showed that the results were representative and authoritative. After two rounds of grading and revision, the variable coefficient (CV) decreased and the Kendall's concordance coefficient (W) increased, which were statistically significant: In the first round, the CV was 0.24 and W was 0.56 (P < 0.001), and in the second, the CV was 0.19 and W was 0.72 (P < 0.001), which indicated that there was a good convergence among the expert opinions. Finally, a scale of difficulty in the tooth extraction containing 12 items at level A and 37 items at level B was formed, including operation difficulty indicators, risk difficulty indicators and common difficulty indicators.@*CONCLUSION@#Based on comprehensive literature retrieval, the study has put forward the concept that difficulty in the extraction of impacted mandibular third molars is composed of operation difficulty and risk difficulty. Using Delphi method, the long-term clinical experience and professional knowledge of experts are transformed into quantitative indicators as a scoring scale. The scale has certain representativeness and authority.

Diagonal root separation method for extracting impacted double-root mandibular third molars / 华西口腔医学杂志

Double-root mandibular third molars are the common types of mandibular third molars that are prone to impac-tion. Based on the summary of clinical cases and experience, the commonly used crown-root separation technique is improved as diagonal root separation technique that divides the roots by the line connecting the distal axis angle to the root furcation. This new method improves the efficiency of the operation and reduces surgical trauma. This paper details the surgical method, minimally invasive mechanics, and key points of this technique, compares the technique with the crown-root separation tech-nique, and discusses their joint applications.

Clinical Use of the Round Tooth Socket Enlargement by Arc Applying in Extraction of Impacted Mandibular Third Molars / 医学研究杂志

Objective To observe the clinical use of the round tooth socket enlargement by arc in extraction the impacted mandibular third molars.Methods We used the round tooth socket enlargement by arc under local anesthesia to extract different type impacted mandibular third molars in 619 patients and analyzed the complication.Results The complications happened in extraction operation was 2.58%.The postoperative complications was 8.07%.Conclusion Use of the round tooth socket enlargement by arc to extract impacted mandibular third molars can reduce complication.It is suitable to extract different type.