Assessment of visibility and extension rate of incisive branch of the inferior alveolar nerve in cone beam computed tomography imagings

Background and Objective: Many surgeries are performed on anterior region of mandible. Incisive branch of the inferior alveolar nerve is located in the anterior region of mandible. The identification of various form of nerve is important for diagnosis and treatment plan. This study was carried out to the assessment of visibility and extension rate of incisive branch of the inferior alveolar nerve in cone beam computed tomography (CBCT) imagings. Methods: This descriptive – analytic study was performed on 105 CBCT images. The presences or absence of incisive branch of the inferior alveolar nerve and assessment of visibility and extension rate of mandibular incisive canal were studied. Results: In 79% extension of the incisive branch of the inferior alveolar nerve were observed. 18.07% of extensions were observed in one-side and 78.31% were bilateral. Extension of the incisive branch of the inferior alveolar nerve was observed to central, lateral and canine tooth in 59%, 26.5% and 14.5% respectively. There was no significant relation beween gender and age of subjects with extension of the incisive branch of the inferior alveolar nerve. Conclusion: Regarding the high visibility of the incisive nerve branches in the lower dental CBCT images this method can be used to evaluate the anterior region of mandible

A Survey on the Accuracy of Radiovisiography in the Assessment of Interproximal Intrabony Defects

Statement of problem: Digital measurement of RVG may improve diagnostic interpretation of radiographs in terms of accuracy, although it has been shown that validity of linear measurements of interproximal bone loss could not be improved by basic digital manipulations.Purpose: The aim of this study was to evaluate the accuracy of RadioVisioGraphy (RVG) in the linear measurement of interproximal bone loss in intrabony defects.Materials and Methods: Thirty two radiographs of 56 periodontally diseased teeth exhibiting interproximal intrabony defects were obtained by a standardized RVG technique and Intrabony defect depths were determined by linear measurement analysis of RVG. The following four distances were assessed intrasurgically: the cemento enamel junction (CEJ) to the alveolar crest, the CEJ to the deepest extention of the bony defect (BD), the occlusal plane to the BD and the OP to the AC. Comparison between RVG measures and intrasurgical estimates were performed using paired t-test.Results: The radiographic measurements overestimated interproximal bone loss as compared to the intrasurgical measurements: CEJ-BD measurement by RVG was 6.803±3.589 mm and intra-surgically was 6.492±3.492 (P<0.000). No statistically significant difference was seen between CEJ and occlusal references in RVG measurements (P<0.729).Conclusion: Radiographic assessment by either the CEJ or occlusal references overestimated bone loss as compared to the intrasurgical gold standard

Frequency of Maxillofacial Fractures among Patients with Head and Neck Trauma Referred to Shahid Beheshti Hospital in Babol, 2018-2019

BACKGROUND AND OBJECTIVE: Head and neck trauma and related injuries account for a high rate of mortality and neurological defects. Since maxillofacial trauma occurs alone or in combination with other severe injuries, this study was performed to determine the frequency of maxillofacial fractures in patients with head and neck trauma referred to Shahid Beheshti Hospital in Babol. METHODS: This cross-sectional study was performed among all patients with maxillofacial trauma who referred to the Oral and Maxillofacial Surgery Center of Shahid Beheshti Hospital in Babol in 2018-2019. Necessary information was collected via history, clinical examinations, facial radiographs and hospital records. CT scan was performed in patients with decreased level of consciousness, neurological symptoms or clinical signs of skull fracture. Data about age, gender, cause of injury, pattern of facial or head injuries, loss of consciousness and GCS score were recorded in the questionnaire and evaluated. FINDINGS: The mean age of patients was 30.55±15.82 years. 44 patients (18.6%) were female and 192 patients (81.4%) were male. Out of 236 patients with head and neck trauma, the rate of upper face, midface, and lower face fractures were 3.4, 53.5 and 29.6%, respectively. The most common areas that were fractured were the Condyle (7.8%) and the Angle (7.3%) of the mandible. CONCLUSION: The results showed that in maxillofacial fractures, the most commonly damaged area is the midfacial area

Evaluation of the Effects of Low-Level Laser Therapy on the Rate of Relapse of Mandibular Incisors after Fixed Orthodontic Treatment: A Randomized Controlled Trial

Background and Objective: Stability is one of the major issues in orthodontics. The purpose of this study is to investigate the effect of Low-Level Laser Therapy on the rate of relapse of mandibular incisors. Methods: This Single-blinded Randomized Controlled Trial consisted of twenty patients (aged 12-18 years) seeking orthodontic treatment. The subjects were divided into two groups with randomly permuted blocks (n=10): experimental and control groups. The Little’s irregularity index was measured on plaster models prior to treatment using American Board of Orthodontic Measuring Gauge. After unraveling of initial crowding, archwires on mandibular anterior segments of both groups were removed. The experimental group received Low-Level Diode Laser at 808 nm wavelength, 250 mW power, 4J energy and continuous wave mode, on coronal third of lower central and lateral incisors and canines’ roots for sixteen seconds three times a week, within a four-week period. The relapse rate was quantified on each plaster model using Little’s irregularity index at the end of first (T1), second (T2), third (T3), and fourth (T4) weeks. Findings: The study population consisted of twenty patients aged 12-18 years who had 5-9 mm crowding and proper oral hygiene. At T1, the relapse rate was 0 mm and 0.05±0.15 mm in experimental and control group, respectively, which was not statistically significant (p=0.343). Over the following weeks, however, there was statistically significant difference between the relapse rate of the two groups (p=0.003). The mean rate of relapse percentage was 4.48±4.31 mm in experimental and 12.06±5.52 mm in control group, which was significantly lower in Low-Level Laser Therapy group. Conclusion: The application of Low-Level Laser Therapy at 808 nm wavelength on mandibular incisors during orthodontic retention phase may slow down the relapse rate. Therefore, it could be considered as an effective adjunct to reduce immediate relapse

A Study of Dentists’ Knowledge about Dental Radiology Principles

BACKGROUND AND OBJECTIVE: The use of dental radiography is inevitable in order for disease diagnosis, assessment and monitoring. Radiogeraphy is potentially harmful due to the use of ionizing radiation. This study was conducted to evaluate dentists&rsquo; knowledge about the principles of dental radiology. &nbsp;METHODS: This cross-sectional study was performed on 600 general dentists willing to cooperate with this study in Amol, Noor, Mahmoodabad and Sari cities located in Mazandaran province, Iran, in 2014. All the data were obtained by means of a questionnaire. The questionnaire included two parts the first part surveyed demographic information, and the second part included 11 items about radiographic technique and equipments. FINDINGS: 500 questionnaires were completed. Among the surveyed population, 335 (67%) and 165 (33%) dentists were male and female, respectively. The mean of practical experiences was 12.35&plusmn;6.68 years. 469 dentists (93.8%) used the dental X-ray machine with digital timer and 404 dentist (80.8%) used the dental X-ray machine with long cone tube. Additionally, 470(94%) X-ray machine had round. Generally, 367 (73.4%) and 374 (74.8%) dentists used bisecting technique and E-speed films, respectively. Also, annual calibration of X-ray devices was suggested by 416 (83.2%) dentists. CONCLUSION: According to our study, dentists&rsquo; knowledge about the dental radiography principles was fair

Radiographic Comparison of the Relation between Mandibular Third Molar Root and Inferior Alveolar Canal in Panoramic Radiography and Cone-Beam Computed Tomography

BACKGROUND AND OBJECTIVE: There is a risk of damage to the inferior alveolar nerve when extracting third molars. A variety of common imaging modalities, such as panoramic radiography (PR) and cone-beam computed tomography (CBCT), are recommended for examination prior to mandibular third molar surgery. The aim of this study was to compare the findings of panoramic radiography and CBCT in evaluating the relation between the root of the mandibular third molar and the inferior alveolar canal. METHODS: In this cross-sectional study, 75 panoramic and CBCT images were evaluated. Cases in panoramic radiography that were suspected of the relation between the root of the mandibular third molars and the inferior alveolar canal were collected. To determine the type of connection of apex and root canal, the samples were divided into 6 groups: normal, inferior alveolar canal path loss, canal path narrowing, sudden canal path change, radiolucent band over the roots, and root curvature. Cases in the panoramic radiograph that were suspected of root contact with the canal were examined by the CBCT in terms of the position of the canal relative to the tooth (buccal or lingual or middle of the root - upper or lower) and the type of connection (whether the tooth is connected to the canal). FINDINGS: In panoramic findings, 23 cases (30.7%) were normal, 19 cases (25.3%) showed canal path loss, 9 cases (12%) canal path narrowing, 5 cases (6.7%) sudden canal path change, 3 cases (4%) radiolucent band over the roots and 16 cases (21.3%) showed root curvature. According to CBCT findings, the position of the canal relative to the root apex was lingual in 39 cases (52%) and there was connection between the mandibular canal and the third molar in 39 cases (78.7%). There was no significant relationship between panoramic radiographic and CBCT findings and only in two cases of specific radiolucent band over the roots, there was a complete agreement between panoramic and CBCT findings. CONCLUSION: Based on the results of this study, if a radiolucent band is observed on the root of the mandibular molars or a sudden change is observed in the canal path, panoramic radiography can be used to detect the relation between the inferior alveolar canal and the root of the third molars

Comparison of Ultrasonography and Cone-Beam Computed Tomography Accuracy in Measuring the Soft Tissue Thickness of Maxillary and Mandibular Gingiva in a Sheep Model

To date, few studies have compared the accuracy of cone-beam computed tomography (CBCT) and ultrasonography in measuring the soft tissue thickness of the maxillary and mandibular gingiva