Objectives. This study aimed to assess the radiographic position of impacted mandibular third molars (IMTMs) and their association with pathological conditions. Materials and Methods. The impaction depth, relationship with ramus, and angulation of 1600 IMTMs and their association with 2nd molar distal caries and root resorption, pathological conditions, and proximity to the mandibular canal were evaluated on panoramic radiographs. The IMTM position was determined based on the depth of impaction according to the Pell and Gregory classification, relationship with ramus according to the Pell and Gregory classification, and angulation according to the Winter’s classification. The classical and Bayesian logistic regressions were applied to analyze the effect of IMTM position on the associated complications using the odds ratio (OR) and 95% confidence interval (credible interval for Bayesian models). Two-tailed value < 0.05 was considered statistically significant. Results. Of 1600 IMTMs evaluated in this study, 195 (12.2%), 252 (15.8%), and 119 (7.4%) had caused second molar distal caries, second molar root resorption, and pathological lesions, respectively, and 872 (54.5%) had contact with the mandibular canal. Impaction angulation was a risk factor for second molar distal caries (maximum OR = 5.01, 95% CI: 3.12–8.18). Changed angulation and greater impaction depth were the risk factors for second molar root resorption (minimum OR = 1.64, 95% CI: 0.58–4.02). Decreased distance between the ramus and distal side of the second molar was a risk factor for associated pathological lesions (minimum OR = 2.73, 95% CI: 1.79–4.25). Mesioangular and horizontal angulations and greater impaction depth were the risk factors for contact with the mandibular canal (maximum OR = 3.44, 95% CI: 2.6–4.57 and minimum OR = 1.3, 95% CI: 094–1.8). Conclusions. The frequency of complications associated with IMTMs was low, but considerable. The occurrence of these conditions might be affected by the impaction position. Thus, regular follow-ups are recommended in order to be able to surgically intervene when the first signs of pathologies arise.
26 February 2022 in Journal of Evidence-Based Dental Practice
Background. Successful dental root canal treatments require a complete knowledge of dental anatomy and root canal morphology. Materials and Methods. One hundred and forty-five cone beam computed tomography (CBCT) images were used to assess the anatomy and morphology of mandibular premolars based on Vertucci’s classifications in a defined group of dental patients in Iran. The number of roots and root canals, root canal morphology, root and canal shape (curvature), existence of C-shaped canal, and influence of sex on each of these were evaluated. A chi-squared test was used for statistical analysis. Results. The mandibular first and second premolars had a single root in 95.97% and 100% cases, respectively. In the mandibular first premolars, 62.2% were of type I, 0.8% type II, 10.9% type III, 0.8% type IV, 20.3% type V, 4.2% type VI, and 0.8% type VII; in the second premolars, 78% of canals were of type I, 3% type II, 11% type III, 7% type V, and 1% type VI. C-shaped canals did not exist in either of the premolars. The most prevalent root and canal shape was straight. The most prevalent root curvature was a distal curvature in both premolars (71.4% and 74% of first and second premolars, resp.). The most prevalent canal curvature was lingual and buccal for the first premolars (7.6% each) and distal for the second premolars (11%). No significant difference was found between men and women in nearly all of the above (). Conclusion. The results suggest that there is a need to conduct further evaluations on finding root and canal variations among more populations to gain better knowledge prior to root canal treatment.
Early diagnosis of oral cancer is critical to improve the survival rate of patients. The current strategies for screening of patients for oral premalignant and malignant lesions unfortunately miss a significant number of involved patients. Optical coherence tomography (OCT) is an optical imaging modality that has been widely investigated in the field of oncology for identification of cancerous entities. Since the interpretation of OCT images requires professional training and OCT images contain information that cannot be inferred visually, artificial intelligence (AI) with trained algorithms has the ability to quantify visually undetectable variations, thus overcoming the barriers that have postponed the involvement of OCT in the process of screening of oral neoplastic lesions. This literature review aimed to highlight the features of precancerous and cancerous oral lesions on OCT images and specify how AI can assist in screening and diagnosis of such pathologies.
Normal airways are a key factor during the craniofacial growth of the young. Therefore, sleep-disordered breathing (SDB) without treatment can have harmful consequences for development and health. This study aimed to evaluate the cephalometric characteristics in non-snoring individuals and snoring subjects, and investigate differences in the pharyngeal airway space between the 2 groups. This case-control study included 70 patients aged over 18 years, selected from a radiology center. The patients were divided into 2 groups: case (35 patients with a history of habitual snoring); and control (35 healthy patients). The Berlin sleep questionnaire was administered to the parents of the patients. The nasopharyngeal airway was measured according to the analysis of Linder-Aronson (1970), and 4 indices were measured and analyzed in each of the lateral cephalometric radiographs. No statistically significant differences were observed in the pharyngeal measurements between the 2 groups, although all means in the control group were higher than in the experimental group. However, there was a significant relationship between gender and the Ba-S-PNS and PNS-AD2 indices. Although the patients with nocturnal snoring had smaller airway dimensions, their pharyngeal measurements were not significantly different from the control group.