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.

Remoción de terceros molares mandibulares con asistencia endoscópica: nota técnica de un nuevo procedimiento quirúrgico para prevenir lesiones del NAI y formación de defectos óseos / Removal of mandibular third molars with endoscopic approach. Technical note of a new surgical procedure to avoid IAN damage and bone defect formation

La variada posición anatómica de los terceros molares mandibulares presenta importantes desafíos asociados a su profundidad y grado de inclinación. Las complicaciones más habituales del procedimiento quirúrgico convencional de extracción se relacionan con la extensa osteotomía y poca visualización del sitio quirúrgico, que pueden generar consecuencias post-quirúrgicas como inflamación, dolor, trismus, lesiones reversibles e irreversibles del nervio alveolar inferior (NAI) o nervio lingual, riesgo de fractura y formación de defectos periodontales del segundo molar. La implementación de soportes rígidos en la óptica endoscópica ha permitido utilizar esta tecnología para realizar abordajes mínimamente invasivos para remover terceros molares mediante accesos flapless con una mínima osteotomía de la zona oclusal, conservando la pared bucal y lingual a través de la visualización directa y magnificada del sitio quirúrgico, adaptable a los movimientos del paciente durante la intervención. En este reporte se presenta un nuevo procedimiento quirúrgico mínimamente invasivo a través de asistencia endoscópica para la conservación ósea en la remoción de terceros molares mandibulares con riesgo de lesión del nervio alveolar inferior.

Anatomic variability of the position of mandibular third molars represents significant challenges associated with its depth and angulation. The most common complications of conventional surgical procedure are related to extensive osteotomy and poor visualization, which can cause postsurgical effects such as inflammation, pain, trismus, reversible and irreversible lesions of the inferior alveolar nerve (IAN) or lingual nerve, fracture risk and formation of a deep periodontal defect on the distal aspect of the second molar. The implementation of rigid endoscopy in optics has allowed to use this technology via a minimally invasive approach to remove third molars by a minimally occlusal flapless ostectomy, preserving the buccal and lingual walls through direct and magnified visualization of the surgical site, adaptable to the patient’s movements during the surgery. In this report, we present a new and minimally invasive procedure through endoscopic assistance for bone conservation in the removal of third molars at risk of inferior alveolar nerve injury.

A comparative evaluation of film and digital panoramic radiographs in the assessment of position and morphology of impacted mandibular third molars.

Background and Objective: Digital photo stimulable phosphor (PSP)-based radiography has many known theoretical advantages over conventional film radiography but its diagnostic efficacy has to be assessed clinically. This study compared the efficiency of conventional film-based panoramic radiographs with that of digital PSP-based panoramic radiographs in the assessment of position and morphology of impacted mandibular third molars. Materials and Methods: We selected a total of 80 impacted mandibular third molars that fulfilled the inclusion and exclusion criteria of this study. Both conventional film-based panoramic radiographs and digital PSP-based panoramic radiographs were taken of all the study samples and the teeth were later surgically removed. Conventional film-based and digital PSP-based panoramic radiographs were compared for their relative efficiencies in the assessment of impaction status, position of tooth, number of roots, root morphology, and proximity to mandibular canal of impacted mandibular third molars. An oral surgeon graded these same factors during/after surgical exploration and this assessment was considered the gold standard. The data obtained were statistically analyzed using descriptive statistics, chi-square test, and McNemar's test. Results: There was no statistically significant difference between conventional film-based radiographic assessment and digital PSP-based panoramic radiographic assessment of impaction status, position of tooth, number of roots, and proximity to mandibular canal of impacted mandibular third molars (P>0.05). However, there was significant difference between the two methods with regard to assessment of root morphology of impacted mandibular third molars (P=0.00). Interpretation and Conclusion : Conventional film-based panoramic radiographs and digital PSP-based panoramic radiographs were comparable in their accuracy in the preoperative study of impacted mandibular third molar with regard to impaction status, tooth position, number of roots, and proximity to the mandibular canal. Digital PSP-based panoramic radiographs were more accurate than conventional film-based panoramic radiographs in the assessment of root morphology of impacted mandibular third molars. Hence, we conclude that digital PSP-based panoramic radiographs can be used as an effective alternative to conventional film-based panoramic radiographs for assessment of position and morphology of impacted mandibular third molars.

Age Estimation Based On Chronological Stages of Mandibular Third Molar Development.

Age estimation using forensic methodologies cover both living and dead people. In this regard, teeth are far more beneficial for being among the most indestructible tissues of the body, both in life and after death. Considering that maturity is function of age the objective of our study was to explore the utility of stages of tooth development in estimating the chronological age, which may be considered as a tool in forensic investigations. The inference drawn from the observations of the study results support the fact that the developmental stages of mandibular third molar yields acceptable estimates of chronological age of a suitable individual.

Electro-acupuncture efficacy on pain control after mandibular third molar surgery

The aim of this study was to evaluate the efficacy of electro-acupuncture (EAC) on postoperative pain control after mandibular third molar surgery. Twenty four young patients (12 male and 12 female) with symmetrically impacted mandibular third molars were selected. Each patient was submitted to two separate surgical procedures under local anesthesia. At one side, extraction was carried out employing both prior (24h) and immediately postoperative application of EAC, while on the contralateral side surgery was carried out without any treatment. EAC was applied on 6 bilateral systemic and 2 auricular points with a WQ10Dl appliance using 40-60Hz frequency for 20 min and individually adjusted intensity. Postoperative pain intensity was rated on a 100 mm visual analog scale (VAS) between 2 and 72 h and recording the amount of analgesics intake after surgery. Statistical analysis was performed using theWilcoxon test. Postoperative pain VAS scores were significantly lower for the EAC group (p<0.05) and analgesic intake decreased (p<0.05) for all evaluated periods (p<0.05). Under the tested conditions EAC therapy is efficient was proved controlling postoperative pain following mandibular third molar surgical removal.

O objetivo desta pesquisa foi verificar a eficácia da aplicação de eletro-acupuntura (EAC) na redução da dor após a exodontia de terceiros molares inferiores inclusos. Foram selecionados 24 pacientes jovens (12 homens e 12 mulheres) com inclusão bilateral de terceiros molares inferiores em posição similar. Cada paciente foi submetido aleatoriamente a dois procedimentos cirúrgicos em dias diferentes: em um deles o dente foi extraído com uma sessão pré-operatória (24 h) e uma pós-operatória imediata de EAC enquanto no outro a extração foi feita sem EAC. A EAC foi aplicada em 6 pontos sistêmicos bilaterais e 2 auriculares com um aparelho WQ10D1 utilizando freqüência de 40-60 Hz por 20 min com intensidade ajustada individualmente. A dor foi avaliada desde 2h até 72h pós-operatórias utilizando a escala visual análoga (EVA) de 100 mm e pelo consumo de analgésicos. Os dados foram comparados pelo teste deWilcoxon. Os escores de dor da EVA foram significantemente menores para o tratamento com EAC (p<0,05) enquanto o consumo de analgésico diminuiu (p<0,05) em todos os períodos (p<0,05). O tratamento com EAC mostrou-se eficiente no controle da dor pós-operatória após cirurgia de extração de terceiros molares inferiores inclusos.

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.