Radiographs of the mandible can be utilized to characterize loss of bone density elsewhere. In addition this investigation indicated that optical densitometry is an inexpensive and low risk method for studying bone density.

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Background: This study aimed to evaluate the cone-beam computed tomography (CBCT) technique considering its reliability to diagnose resorption due to maxillary impacted canine. Methods: In this cross-sectional study, 68 CBCT images were observed by two oral and maxillofacial radiologists. The position of the impacted maxillary canine was assessed, and the severity of root resorption in adjacent teeth was determined in two rounds by viewing. Finally, statistical analyses were performed according to the percentage of agreement, intra-class correlation coefficient, and kappa. The data sheets were filled out by two radiologists who observed the CBCT images in two separate weeks and recorded their opinions about the position of the crown and root of the impacted maxillary canine. Further, four adjacent teeth were examined for root resorption. Results: In most cases, no root resorption was observed in the lateral, central, and first premolars; however, the reported percentage of root resorption in the lateral premolar was higher than that of the others, and no root resorption was reported in the second premolars. Agreement on crown and root position was reported to be above 90% in all observations. In addition, the percentage of agreement was 98.5%, 95.6%, 98.5%, and 100% for root resorption, central incisor, lateral incisor, the first premolar, and the second premolar, respectively. Maxillary impacted canines were examined considering root resorption in adjacent teeth using CBCT, and its interpretation was reliable. Conclusions: Utilization of CBCT provides a worthy data about the impacted maxillary canine localization and effects on adjacent teeth, for more explanation and treatment of these cases.

Introduction This study aimed to assess the effect of slice thickness of 3D printer in fabrication of surgical guide (SG) on the accuracy of dental implant placement. Materials and Methods After preparation of two dry human mandibles, Cone-beam computed tomography (CBCT) scans were obtained, and the location and direction of implants in the edentulous ridge of the mandible were identified using Romexis software. Data in STL format were transferred to a 3D printer and two SGs with 50 µm and 100 µm thicknesses were fabricated for each mandible. Drilling was performed using two SGs. The pre- and post-intervention CBCT scans were superimposed to measure the magnitude of differences. The two groups were compared using the Mann-Whitney U test. Results No significant difference was noted in SGs with 50 and 100 µm thicknesses in the coronal and apical regions of the implants or the depth of drilling. However, the difference in angular deviation was statistically significant. Conclusion Considering the higher accuracy of SGs with 50 µm thickness (despite the presence of a significant difference in AD between the SGs with different thicknesses), it is recommended to use a SG with 50 µm thickness in cases where anatomical limitations exist.

Congenital diffuse infiltrating lipomatosis of the face (CDIL-F) is a rare clinicopathological entity with an unknown etiology, in which mature adipose tissue infiltrates the soft tissue structures in one side, and causes considerable asymmetry. Herein, we report a case of CDIL-F who underwent many surgical procedures without definite diagnosis during 12 years.  CDIL-F presents symptoms with various severity levels due to infiltration of adipose tissue that makes removal difficult. Thus, it is recommended to inform patients about the high rate of recurrence.

Background and Aim: Considering the effect of alcohol on bones, consuming alcohol may have some consequences on orthodontic tooth movement. The present study was aimed to evaluate the effect of alcohol consumption on bone density and orthodontic tooth movement in rats. Materials and Methods: In this experimental study, thirty rats were divided into three groups and underwent 3 weeks of different injection regimen. Group A received no injection while rats in group B and C were infused with saline and a mixture of alcohol and saline respectively. Tooth movement at day 21 was measured by leaf gauge. Optical density was measured using a digital densitometer at the beginning and the end of the experiment around four lateral cephalometric landmarks. One-way analysis of variance (ANOVA) was used to determine the differences in tooth movement. Changes in bone density were analyzed using paired T-test after evaluation of interactions. Results: Mean tooth movement in group C was (0.4± 0.06 mm) was significantly higher than no injection (0.26± 0.04 mm) and saline infusion (0.29± 0.04 mm) groups (P=0.001). Significant decrease in bone density were observed in alcohol injected group in skull (P=0.005) and mandible(P=0.004) after three weeks of experiment. Conclusion: Alcohol infusion could induce decreased bone density which might be a reason for faster tooth movement in alcohol-treated rats.

Background and Aim: Captopril is an oral angiotensin-converting-enzyme (ACE) inhibitor extensively used in the treatment of hypertension and heart failure. ACE has been suggested to function in bone cells and might therefore impact orthodontic tooth movement (OTM). Considering the controversy surrounding the effects of ACE and its inhibitors on osseous tissues, we aimed to evaluate the effect of captopril on OTM for the first time in a rat model. Materials and Methods: Orthodontic appliances were fixed between the left first molars and incisors of 30 rats divided into three groups (n=10) receiving captopril, saline or no treatment. Following sacrifice on day 21, the amount of tooth movement was measured as the distance created between the first and second molars. Bone density was assessed by lateral cephalograms on days 1 and 21 and osteoclast number, root resorption and periodontal ligament (PDL) width were analyzed histologically. One-way ANOVA followed by post-hoc test were used for statistical analysis (P<0.05) Results: OTM significantly increased in the captopril group compared to the saline and no-treatment groups (P<0.05). Bone density significantly decreased in the mandible of the captopril group from day 1 to 21 (P<0.05). No significant differences were found in the histological variables except for the significant increase in PDL width at the mesioapical aspect in the captopril group. Conclusion: The present study showed that captopril administration could lead to increased OTM and decreased bone density in rats. Further studies are suggested to clarify its exact role at the cellular and molecular levels.