Comparison of panoramic radiography and cone-beam computed tomography images for detecting external root resorption of mandibular second molar associated with third molar impaction / 口腔医学

Objective@# To compare the diagnostic performance between panoramic radiography(PR)and cone beam computed tomography(CBCT)in the assessment of external root resorption(ERR)of mandibular second molars associated with impacted third molars. @*Methods@# A total number of 832 patients with 1 074 mesially and horizontally impacted mandibular third molars treated at our institution from January 2019 to December 2020 were retrospectively analyzed. Presence of ERR on the adjacent second molar was investigated with PR and CBCT. Factors affecting the diagnostic accuracy of PR were determined. @*Results@# The overall incidence of ERR in second molars was 33.15%(356/1 074)as detected by CBCT images. The accuracy of PR was 66.39%. Multivariate Logistic regression analyses further revealed that middle and Class Ⅲ impaction, crown contact or overlap with the root of adjacent tooth were risk factors for inaccurate diagnosis of PR(P<0.05). @*Conclusion@#The accuracy of detection on ERR of mandibular second molar associated with impacted third molar using panoramic radiography is lower. CBCT is recommended for this clinical scenario.

Prevalence of impacted mandibular third molars and its association with distal caries in mandibular second molars using cone beam computed tomography / Prevalencia de terceros molares mandibulares impactados y su asociación con caries distales en segundos molares mandibulares mediante tomografía computarizada de haz cónico

This study evaluated the prevalence and eruption's pattern of impacted mandibular third molars (IMTM) and the influence of their eruption status on the distal caries of mandibular second molars (MSM) using cone-beam computed tomography (CBCT). Material and methods: CBCT images taken for different purposes in private dental practices were analyzed retrospectively. Radiographic assessment included: prevalence of IMTM, degree of angulation, level of impaction and type of IMTM. Furthermore, the distance between the cement-enamel junctions (CEJ) of second and third molars and the occurrence of caries lesion on the distal surface of MSM was also evaluated. Data were analyzed by chi square test and logistic regression was used to find the association between distal caries of MSM and eruption status of IMTM. Results: Three hundred and eight CBCTs were screened, the prevalence of IMTM was 36.88% and their angulation degree were mostly less than 90º (mesioangular). Amongst those with impaction, 58 subjects (43%) had distal caries on MSM, 29.6% in females and 30.4% in the age group 19-27 years. Caries on the distal side of MSM were significantly associated with age, level and type of impaction, angulation degree and CEJ distances (p<0.05). Conclusions: The prevalence of IMTM is high (36.88%) and there are significant relationships between angulation degree, level and type of impaction, and CEJ distances with caries on the distal side of MSM.

Introducción: Este estudio evaluó la prevalencia y el patrón de erupción de terceros molares mandibulares impactados (TMMI), y la influencia de su estado de erupción en la caries distal de los segundos molares mandibulares (SMM) mediante tomografía computarizada de haz cónico (TCHC). Material y métodos: se analizaron retrospectivamente las imágenes de TCHC tomadas para diferentes fines en prácticas dentales privadas. La evaluación radiográfica incluyó: prevalencia de TMMI, grado de angulación, nivel de impacto y tipo de TMMI. Además, también se evaluó la distancia entre la unión amelocementaria (UAC) de los segundos y terceros molares y la aparición de lesión de caries en la superficie distal de SMM. Los datos se analizaron mediante la prueba de chi cuadrado y se usó la regresión logística para evaluar asociaciones entre la caries distal de SMM y el estado de erupción de TMMI. Resultados: Se examinaron 308 TCHC, la prevalencia de TMMI fue de 36.88% y su grado de angulación fue mayoritariamente menor a 90º (mesioangular). Entre aquellos con impacto, 58 sujetos (43%) tenían caries distales en los SMM, 29.6% eran mujeres y 30.4% pertenecieron al grupo de edad de 19-27 años. Las caries en el lado distal de MSM se asociaron significativamente con la edad, el nivel y el tipo de impactación, el grado de angulación y las distancias UAC (p<0.05). Conclusiones: la prevalencia de TMMI es alta (36.88%) y existen relaciones significativas entre el grado de angulación, el nivel y el tipo de impacto, y las distancias UAC con presencia de caries en el lado distal de los SMM.

Impacted mandibular third molar: Comparison of coronectomy with odontectomy

Damage to the inferior alveolar nerve (IAN) while extracting lower third molars is often caused by the intimate relationship between the nerve and the roots of the teeth. The aim of this study was to compare the sequelae of coronectomy with odontectomy in impacted mandibular third molars. Patients and Methods: This study included thirty patients which were divided into two groups, Group-I (test group) including 15 patients undergoing coronectomy and Group-2 (control group) of 15 patients undergoing odontectomy. Investigations included digital orthopantomogram. The parameters for this study included pain, swelling, nerve paresthesia, trismus, postoperative infection, postoperative wound dehiscence, postoperative pocket depth, and migration. Results: In Group-1 (coronectomy group), the patients underwent follow-up for 6 months to evaluate migration of the retained mandibular third molar root which was in proximity with the IAN. There was a mean increase in migration when the distance from the inferior border of IAN until the apex of the retained mandibular third molar root was measured which was by 3.43 mm after 6 months of follow up. Conclusion: On statistical analysis, the result in this study showed no statistical difference in both the groups in all the parameters that were taken.

The relative location between the mandibular third molar and inferior alveolar canal studied by CBCT / 实用口腔医学杂志

Objective: To determine the positional relationship between impacted mandibular third molar(IMTM) and mandibular canal(MC) by CBCT. Methods: 664 IMTMs with root apexes contacted to MCs on panoramic radiograph were further examined by CBCT,the exact positional relationship between IMTMs and MCs was observed and analyzed by I-Dixel software. Results: The 664 cases were divided into lowly(6. 3％),intermediately(60. 7％) and highly(33. 0％) impacted groups by the depth of IMTMs in mandibulae showed on CBCT images. The distance(mm) from the root apexes of IMTMs to the intact superior wall of MCs(n = 329) in lowly, intermediately and highly impacted cases were 1. 39 ± 1. 38,1. 28 ± 1. 03 and 1. 79 ± 1. 54 respectively(P ＜ 0. 05). MCs on the buccal side,lingual side,under the IMTMs and between the root apexes were found in 49. 8％,12. 0％,36. 6％ and 1. 5％ of the cases; the MC wall deffect was found in 65. 8％,27. 5％ and 95. 0％ of the cases with the MCs under,on buccal and lingual side of the IMTMs, respectively(P ＜ 0. 001). Conclusion: CBCT examination is necessary for the determination of the positional relationship between MC canal and IMTM with the root apex cotacted or overlapped to MC.

C–reactive protein estimation: A quantitative analysis for three nonsteroidal anti‑inflammatory drugs: A randomized control trial.

Context: C‑reactive protein (CRP) estimation for quantitative analysis to assess anti‑inflammatory action of nonsteroidal anti‑inflammatory drugs (NSAIDs) after surgery in maxillofacial surgery. Aims: This study was to evaluate the efficacy of CRP as a quantitative analysis for objective assessment of efficacy of three NSAIDs in postoperative inflammation and pain control. Settings and Design: The parallel study group design of randomization was done. Totally 60 patients were divided into three groups. CRP was evaluated at baseline and postoperatively (immediate and 72 h) after surgical removal of impacted lower third molar. The respective group received the drugs by random coding postoperatively. Subjects and Methods: The assessment of pain control and inflammation using NSAIDs postoperatively after surgical removal of impacted lower third molar was qualitatively and quantitatively assessed with CRP levels. The blood sample of the patient was assessed immediate postoperatively and after 72 h. The visual analog scale (VAS) was used for assessment of pain and its correlation with CRP levels. Statistical Analysis: Comparison of difference in levels of CRP levels had P < 0.05 with immediate postoperative and baseline levels. The duration of surgery with association of CRP levels P = 0.425 which was nonsignificant. The pain score was increased with mefenamic acid (P = 0.003), which was significant on VAS. Results: Diclofenac had the best anti‑inflammatory action. There was a significant increase in CRP levels in immediate postoperative values and 72 h. CRP test proved to be a useful indicator as a quantitative assessment tool for monitoring postsurgical inflammation and therapeutic effects of various anti‑inflammatory drugs. Conclusions: CRP test is a useful indicator for quantitative assessment for comparative evaluation of NSAIDs.

A clinical comparison of impacted mandibular third molar extraction at different ages of patients / 实用口腔医学杂志

330 cases of impacted mandibular third molar were divided into 3 groups,A:younger than 18 years,B:18-25-year-old,C:ol-der than 25-year.Operation time(min)of group A,B and C was 21.95 ±5.86,6.45 ±4.92 and 18.77 ±9.64(B vs A or C,P <0.01), intraoperative complication rates were 2.73%,6.36% and 30.91%(P <0.01),postoperative complication rates were 51.82%,23.64%and 66.36%(P <0.05),respectively.18-25 year-old is the suitable age for removal of impacted mandibular third molars.

Evidence-based medical analysis of the applicaiton of microport extraction to impacted mandibular third molar removal / 实用口腔医学杂志

Objective:To evaluate the effectiveness of microport extraction of the impacted mandibular third molar removal.Meth-ods:According to the systematic review and meta-analysis,the randomized controlled clinical trials published till October 2012 were searched and collected using the method of evidence-based medicine.Results:8 clinical research papers including 1 915 subjects were collected.Complication of microport extraction(958 cases)was less than that of traditional operation(957 cases).Conclusion:Microport extraction of impacted mandibular third molar may reduce the complications.

Immunohistochemical analysis of CK 18 in dental follicles of impacted third molars: A pilot study.

Objective: Odontogenic tumors are lesions derived from epithelial, ectomesenchymal, and/or mesenchymal elements that still are, or have been, part of the tooth-forming apparatus. Approximately 80% of odontogenic tumors occur in the mandible, with a marked predilection for the posterior region, and are often associated with an unerupted tooth. The aim of this study was to determine whether cytokeratin (CK) 18 immunostaining decorated the follicular tissue removed at the time of prophylactic extraction of impacted mandibular third molars, which might suggest oncofetal transformation. Materials and Methods : Fifty-four impactions met the study inclusion criteria, of which 24 cases showed the presence of reduced enamel epithelium and/or connective tissue with odontogenic epithelium, which were subjected to CK 18 immunostaining. Results: All 24 cases with adequate epithelium were CK 18 immunonegative. Conclusion: There was no oncofetal transformation in the odontogenic epithelia of the dental follicles studied. Thus, although we reaffirm that evaluation of follicular tissue is imperative since disease conditions may be found in minute follicular spaces, development of odontogenic cysts and tumors is unlikely.

Sublingual piroxicam in the management of postoperative pain after surgical removal of impacted mandibular third molar.

Introduction: Surgical removal of impacted mandibular third molar is one of the most commonly performed procedures in oral and maxillofacial surgical practice. The role of preoperative and postoperative medications for management of postoperative complications has been extensively evaluated. Aim: To assess the therapeutic effect of a single dose of 40 mg sublingual piroxicam (study group) vs 150 mg oral diclofenac (50 mg thrice a day) (control group) in patients undergoing surgical removal of impacted mandibular third molar. Materials and Methods: A total of 100 patients with asymptomatic impacted mandibular third molars were randomized into two groups. One group received two 20-mg tablets of piroxicam once daily on the first and second postoperative days, followed by one 20-mg tablet on the third post-operative day. The other group received one tablet of diclofenac 50 mg orally thrice daily on the first, second, and third post-operative days. Repeated extraoral examinations were done for continuous assessment of swelling, trismus, and reduction in pain. Ovearall impression of the treating physician and the patient regarding efficacy of study drugs were recorded at the end of the study. Results: In the piroxicam group there was >50% reduction in pain on all three days postoperatively. The incidence of swelling and trismus was found to be higher in the control group as compared to the study group. Adverse events, such as gastrointestinal (GI) disturbances, were significantly higher in the diclofenac group (11%) as compared to the piroxicam group (0%). Conclusion: Two sublingual piroxicam 20 mg tablets once daily has better efficacy and tolerability profile than diclofenac 50 mg one tablet thrice daily in the management of pain after surgical removal of impacted mandibular third molar. Study Title: A Comparative Study to Evaluate Clinical Efficacy and Safety of Sublingual Piroxicam and Diclofenac in the Management of Pain after Surgical Removal of Impacted Mandibular Third Molar.

A comparison of two methods of extracting impacted mandibular third molars / 实用口腔医学杂志

Objective:To study the feasibility of extraction of impacted mandibular wisdom teeth using turbine drill and new instruments. Methods: 600 patients with impacted mandibular third molars were divides into 2 groups. A group used turbine drill and new instruments to extract the impacted mandibular third molar. B group used the dental chisel to extract the impacted mandibular third molar. The operation time, intraoperative and postoperative complications were recorded to assess the effects of the methods. Results: The operation time of group A and group B was (22.285±12.025 01) min and (16.115±12.078 62) min respectively. The operation time of group A was shorter(P<0.05). The intraoperative and postoperative complication incidence rate was lower(P<0.05). Conclusion: Turbine drill and new instruments method is superior to dental chisel method in the extraction of impacted mandibular wisdom teeth.