The Evaluation of Condylar Position Change in the Asymmetric Mandible Following Sagittal Split Osteotomy.

BACKGROUND: The change of condyle position following orthognathic surgery affects the stability of treatments. This study aims to assess the correlation between the amount of condyles' position change and the severity of mandibular asymmetry following BSSO. MATERIALS AND METHODS: This is a cross-sectional study. Subjects with asymmetric mandibular prognathism following BSSO were studied. Subjects were classified into 2 groups: group 1, subjects had mandibular asymmetry without occlusal cant and underwent BSSO. Group 2, subjects had mandibular asymmetry with occlusal cant and underwent BSSO+ Lefort I osteotomy. The condyle position was evaluated using cone-beam computer tomography (CBCT). Pearson's correlation test was used to assess any correlation between the condyle changes and the change in the mandible in sagittal and anterior-posterior directions. RESULTS: A total of 44 subjects were studied. In group 1, the condyle tilted outward in the deviated condyle and inward in the non-deviated condyle immediately after osteotomy. After 12 months, both condyles showed a rotation relative to the original position. In group 2, the condyles of the deviated sides and non-deviated sides moved inferiorly after surgery (condylar sagging), which was more significant in the non-deviated sides. The condyle rotation was similar to group 1. The severity of asymmetry and occlusal cant correlate with the condylar position change in the two groups. CONCLUSION: The severity of mandibular asymmetry correlates with the amount of condyles' position change immediately after BSSO. However, the condyles tend to return to their original position 12 months later.

Clinical and Cephalometric Changes in Long-face Patients With Retrogenia Following the Novel B-genioplasty Technique.

BACKGROUND: The chin plays a fundamental role in facial attractiveness. Accordingly, several surgical procedures have been proposed for chin contouring. This study aimed to introduce "B-genioplasty" as a novel genioplasty technique and assess the clinical and cephalometric changes in long-face patients with retrognathia following the novel B-genioplasty. METHODS: This is a cross-sectional study. Subjects with class I occlusion increased lower facial height and retrognathia underwent B-genioplasty in this prospective experimental study. Soft and hard tissue cephalometric measurements were made, and the depth of the notch in the lower border of the mandible was measured on lateral cephalograms at 6 months postoperatively and compared with baseline. Patient satisfaction with the outcome was also assessed. RESULTS: Seventeen subjects were studied. Ten (58%) patients underwent rhinoplasty plus genioplasty. All patients were satisfied with the outcome. The step/notch in the lower border of the mandible was not detected in clinical examination in any patient. The mean notch depth was 0.5±0.83 mm on lateral cephalograms. The change in all soft and hard tissue cephalometric parameters was significant at 6 months postoperatively compared with baseline (P<0.001 for all). CONCLUSION: B-genioplasty caused satisfactory clinical and cephalometric changes in long-face patients with retrognathia, including prevention of step/notch in the inferior border of the mandible, significant reduction of gonial angle, correction of the mandibular plane, and reduction of lower facial height.

Does leucocyte- and platelet-rich fibrin enhance neurosensory recovery after genioplasty? A double-blind, split-mouth, randomised clinical trial.

Neurosensory disturbances (NSD) are common after genioplasty. In this study we aimed to assess the recovery of NSDs with or without leukocyte- and platelet-rich fibrin (L-PRF) following genioplasty. In this double-blind, split-mouth, randomised clinical trial, L-PRF was applied around the mental nerve at the osteotomy site in genioplasty (treatment side). The contralateral side was considered the control side. Two-point discrimination (TPD) test, brush test, and self-reported NSDs (SR-NSD) were used to determine NSD at one, four, and 12 months after genioplasty. Twenty patients were studied. At one and four months after osteotomy, the mean scores of TPD and SR-NSDs were significantly different between the treatment and control sides (p = 0.04, p = 0.01, respectively). The mean of TPD and SR-NSDs was not statistically different on both sides 12 months after operation (p = 0.05, p = 0.71, respectively). The application of L-PRF may enhance the speed of NSD recovery four months after genioplasty.

Use of Leukocyte-PlateletRich Fibrin in Conservative Management of Odontogenic Keratocyst: A Case Report.

A 29-year-old female patient was referred to the Department of Oral and Maxillofacial Surgery in Taleghani Hospital of Shahid Beheshti University of Medical Science, Tehran, Iran, in 2019, complaining of increased volume and pain in the posterior mandibular region. Cone-beam computed tomography and multislice computed tomography were performed, and an incisional biopsy was done. The histopathologic examination confirmed the diagnosis of Odontogenic Keratocyst (OKC). Surgical treatment was performed with marsupialization. After a year of follow-up, the resultant small-sized cyst was curetted, and Leukocyte-PlateletRich Fibrin (LPRF) was placed in the bony depression. The significant healing of the lesion was noted on regular follow-up visits with complete resolution at 15 months. This report showed that the application of LPRF might accelerate the healing of soft tissues and bone regeneration with no inhibitory effect on the natural healing process.

Efficacy of Low-Intensity Pulsed Ultrasound for Orthodontic Pain Control: A Randomized Clinical Trial.

Objectives: This study aimed to assess the efficacy of low-intensity pulsed ultrasound (LIPUS) for orthodontic pain control. Materials and Methods: This spilt-mouth randomized controlled clinical trial was performed on 44 mandibular first molars of 22 orthodontic patients at the Orthodontics Department of Shahid Beheshti Dental University. Elastomeric separators were placed at the mesial and distal of mandibular right and left first molars by separating pliers. Randomly, LIPUS was used at one side for 7 min and the same device with 0-degree intensity was used as sham for the other side on the facial skin. The same procedure was repeated after 24 h. Patients recorded their level of pain at 1, 6, and 24 h, and also on days 2 to 7 after, using a visual analog scale (VAS). Results: The effect of type of treatment (P=0.019), time of assessment (P<0.000) and the interaction effect of type of treatment and time of assessment (P=0.055) on the pain score were all significant. The mean pain score in the LIPUS group was significantly lower than that in the control group at 24 h (P=0.002), 4 days (P=0.031) and 5 days (P=0.035). Conclusion: LIPUS can be safely used during orthodontic treatment for pain control since it is safe, non-invasive, low-cost, and easy to use.

What factors affect the attachment of the inferior alveolar nerve to the buccal plate following sagittal split osteotomy?

PURPOSE: This study aimed to assess the factors that can possibly affect the positioning of the inferior alveolar nerve (IAN) in the proximal or distal segment following sagittal split osteotomy (SSO). MATERIALS AND METHODS: This was a prospective cohort study. The patients were assigned according to the position of the IAN: the IAN was attached to the buccal plate in group 1 (27 SSOs), while it was in the distal segment in group 2 (83 SSOs). RESULTS: The mean of the buccolingual thickness of the proximal segment at the vertical cut of the osteotomy (BLTP) was 5.0 ± 0.62 mm in group 1 and 4.16 ± 0.72 mm in group 2. The mean of the distance between the IAN and the external cortical bone at the distal of the second molar before the osteotomy (IANB) was 0.5 ± 0.24 mm in group 1 and 1.24 ± 0.45 mm in group 2. There were significant differences for the mean BLTP and IANB between the two groups (P = 0.001). CONCLUSION: It seems that the thickness of the buccal plate of the proximal segment, the distance from the IAN to the external cortical bone, the osteotomy technique, and the presence or absence of impacted third molars may be associated with the positioning of the IAN following SSO.

Penetrating Orbital Injury; a Case Report and Treatment Algorithm.

Penetrating orbital trauma (POT) consists of high and low velocity penetrating injuries that may lead to severe consequences such as visual impairment and globe tearing. It has been reported to make up 30% to 50% of all orbital injuries. POT requires a multidisciplinary approach due to complex orbital injury, which involves eye function, brain injury, and facial aesthetics. In this report, we presented a case of POT due to knife injury in which the knife blade was removed and bleeding was controlled, the patient's general condition after surgery was good, but the vision of the right eye was lost.

The effect of autologous leukocyte platelet rich fibrin on the rate of orthodontic tooth movement: A prospective randomized clinical trial.

OBJECTIVE: The aim of this study was to evaluate the effect of LPRF, placed in extraction sockets, on orthodontic tooth movement (OTM). MATERIALS AND METHODS: Thirty extraction sockets from eight patients (five males, three females, with a mean age of 17.37 years; range 12-25 years) requiring extraction of first premolars based on their orthodontic treatment plan participated in this split-mouth clinical trial. In one randomly selected quadrant of each jaw, the extraction socket was preserved as the experimental group by immediate placement of LPRF in the extraction socket. The other quadrant served as the control group for secondary healing. Immediately, the teeth adjacent to the defects were pulled together by a NiTi closed-coil spring with constant force. A piece of 0.016 × 0.022-inch stainless steel wire was used as the main arch wire. The amount of OTM was measured on the study casts at eight time points with 2-week intervals for 3 months. Analysis of random effect model was performed for the purpose of comparison between the experimental and control groups. RESULTS: According to the random effect model, a statistically significant difference was found between the experimental and control group in rate of OTM (P = 0.006). CONCLUSION: According to the results, application of LPRF, as an interdisciplinary approach combining orthodontics and surgery, may accelerate OTM, particularly in extraction cases.