A Rare Case of Orthokeratinized Odontogenic Cyst (OOC) in the Posterior Mandible of a Young Adult 18-Year-Old Boy.

Orthokeratinized Odontogenic Cyst (OOC) is a rare odontogenic cyst, which is important because it has a low recurrence potential, but it has a percentage of the potential for malignant changes. OOC characteristics can be different from OKC (odontogenic keratocyst), which was once classified in its category. The microscopic view of OOC cyst is the reason for its easy identification from OKC, the orthokeratinized epithelial covering and the clear granular layer, and the hyperplasia of the basal layer, and the smooth surface of this cyst. OOC cyst treatment is conservative and can be usually carried out by enucleation. In terms of gender predominance, it is often reported in men. Furthermore, OOC is more common in the 3rd and 4th decades of life. Hereby, we report a rare case of OOC in the posterior mandible of a young adult 18-year-old boy and its treatment method. The clinical and diagnostic points of view and the treatment options were discussed in this article.

The Beneficial Effect of Preoperative Dexmedetomidine in Controlling Postoperative Pain, Nausea, and Vomiting After Orthognathic Surgery: A Triple-blind Randomized Clinical Trial.

PURPOSE: Controlling postoperative pain and nausea (PONV) following orthognathic surgery can be challenging. The aim of the study was to assess the efficacy of dexmedetomidine (DEX) in reducing pain and preventing nausea and vomiting in subjects undergoing orthognathic surgery. METHODS: The authors implemented a triple-blinded, randomized clinical trial. Healthy adults with class III jaw deformity scheduled for bimaxillary orthognathic surgery were included. Subjects were randomized to the DEX or placebo groups. The DEX group received premedication with DEX 1 µg/kg IV over 10 minutes followed by a maintenance dose (0.2 µg/kg/hour) while the placebo group received normal saline. The primary outcome variables were postoperative pain, postoperative nausea, and postoperative vomiting . Pain was assessed using a visual analog scale at 1, 3, 6, 12, 18, and 24 hours, postoperatively). Nausea and vomiting were recorded throughout the postoperative period. Statistical analysis was performed using χ2, t test, and repeated measures ANOVA with a P value < .05 considered significant. RESULTS: A total of 60 consecutive subjects with a mean age of 24.6 ± 3.5 years completed the study. There were 38 females (63.33%) and 22 males (36.66%). The mean visual analog scale was significantly lower in the DEX group at all time-points (P < .05). There was a significantly greater demand for rescue analgesics in the placebo group compared to the DEX group (P = .01). Fourteen subjects (46.7%) in the placebo group and one subject (3.3%) in the DEX group reported nausea (P < .001). Postoperative vomiting was not observed in any of the subjects. CONCLUSION: Premedication with DEX can be considered a viable treatment option for reducing postoperative pain and postoperative nausea after bimaxillary orthognathic surgery.

Emergence from Anesthesia: A Comparison between Isolated Mandibular Setback and Bimaxillary Orthognathic Surgeries in Skeletal Class III Patients.

Background: We aimed to compare the emergence from anesthesia between the isolated mandibular setback and bimaxillary orthognathic surgeries in Skeletal Class III Patients. Methods: All healthy patients with skeletal class III deformity admitted to Mashhad Dental School, Mashhad, Iran from the years 2017 to 2018 were included in this study. They were candidates for either bimaxillary orthognathic surgery (Bimax surgery) through a combination of mandibular setback surgery plus maxillary advancement or isolated mandibular setback (Monomax surgery). The predictor variable was the type of jaw displacement and anesthesia duration, while the outcome variable was the duration of emergence from general anesthesia. The duration of emergence from anesthesia was calculated from the time the patient was transported to the recovery room until the time of safely discharging from the recovery room. For statistical analysis, the significance level was set at 0.05 using SPSS 21. Results: A total of 81 consecutive patients, comprising 45 (55.6%) males and 36 (44.4%) females, with an average age of 23.15±4.58 years were recruited. Among the participating patients, 56 (69.1%) underwent bimaxillary surgery while the other 25 (30.9%) were treated with Monomax surgery. Regardless of the type of performed surgery, the duration of general anesthesia was the only factor to be significantly correlated to the length of emergence from anesthesia (P= 0.001). Conclusion: Increased exposure time to general anesthesia might result in a longer emergence from anesthesia, despite the type of performed orthognathic surgery. Further clinical trials are needed to support the relevancy.

Does Mandibular Advancement Orthognathic Surgery Lead to TMJ Dysfunction in Skeletal Class 2 Patients? A Quasi-Experimental Trial in an Iranian Population.

BACKGROUND: We aimed to evaluate the possibility of temporomandibular joint (TMJ) dysfunction following mandibular advancement surgery in skeletal class 2 patients. Methods: All healthy non-syndromic patients with Class 2 deformity, who were eligible for mandibular advancement surgery, were included in this before-after quasi-experimental study. The main intervention was mandibular advancement through bilateral sagittal split osteotomy (BSSO). Maxillary impaction or setback surgery using LeFort 1 osteotomy was simultaneously performed in some cases. Variables such as TMJ pain, clicking, crepitus, or any other type of sounds or complaint as well as the amount of maximum mouth opening (MMO) were evaluated before surgery and two months postoperatively. Results: Thirty patients including 15 men and 15 women with a mean age of 23.3 ±2.7 yr were studied. The mean amount of mandibular advancement displacement was 3.30 ± 0.87 mm. The rate of TMJ dysfunctions and complaints was relatively low two months postoperatively when compared to the preoperative state. Postoperative evaluation demonstrated that there was no significant correlation between the presence of TMJ symptoms and dysfunctions and the type of surgery. After treatment was completed, the mean MMO reduced significantly from 39.03±5.86 to 38.12±6.05 (P<0.001). Conclusion: Mandibular advancement with BSSO surgery in skeletal class 2 patients did not clinically lead to TMJ dysfunctions. Among all the investigated factors, only preoperative pain, noises, or complaints were proven to have predictive value for postoperative TMJ dysfunction.

Piezotome Versus Surgical Bur: Which is More Effective in Reducing the Postoperative Pain and Edema Following Open Sinus Lift Surgery?

OBJECTIVE: The aim of this study was to compare the piezotome versus surgical bur on postoperative edema and pain following open sinus lift surgery. MATERIALS AND METHODS: This was a double-blinded split mouth randomized clinical trial. The subjects who were candidates for bilateral open sinus lifting in the posterior maxilla were included in this experiment. Each maxillary side was assigned randomly to one group, piezosurgery or surgical diamond bur for sinus lifting. Postoperative pain and edema were evaluated on the second and seventh days after the surgery, using the VAS scale. Data were analyzed by SPSS software. RESULTS: In this study, 20 subjects including 10 females (50%) and 10 males (50%) with a mean age of 50.87 ± 9.04 years participated. The mean duration of surgery in piezosurgery (240.13 ± 49.5 s) was significantly higher than the surgical bur technique (135.07 ± 43.53 s) (P < 0.001). Pain and edema were significantly decreased on the seventh day postoperatively compared to the second day in both group (P < 0.05). Pain and edema were similar between the two study groups on the second and seventh days after surgery. CONCLUSION: The results of this study depicted that the piezosurgery clinical outcomes were similar to surgical bur following open sinus lift surgery.

The Effect of Orthognathic Surgery on the Hyoid Bone Position in Skeletal Class III Patients: An Evaluation Using Cephalometric Analysis.

BACKGROUND: This study aimed to investigate the positional changes of the hyoid bone following orthognathic surgery in skeletal class III patients. METHODS: This double-blinded quasi-experimental study was carried out in Mashhad University of Medical Sciences, Iran, from Apr 2019 to Jun 2020. All skeletal Class III patients who were candidates for orthogenetic surgery were included. They underwent mandibular setback surgery using bilateral sagittal split osteotomy. Cephalometric assessments in relation to hyoid bone position and posterior airway space (PAS) were conducted one day preoperatively (T0), as well as one week (T1), six months (T2) and one year (T3) postoperatively, determining the parameters like the Long axis of the hyoid bone (LAH), Retrognation (RGn), Hyoidale (H), Palatal plane (PP), Mandibular plane (MP) and C3 Vertebrae (C3). All cephalograms were examined using AudaxCeph, Planmeca software. The data analysis was performed via SPSS-19 (P<0.05). RESULTS: 25 class III patients, including 18 females (72%) and 7 males (28%) with a mean age of 24.32±5.87, were studied. The cephalometric analysis demonstrated significant decreases in variable angles during the follow-up periods, except for LAH-MP angle (P<0.001). The hyoid bone moved downward and backward relative to its original position following the mandibular setback surgery. However, the bone gradually returned to the preoperative location between 6 to 12 months postoperatively. CONCLUSION: The findings revealed the downward and backward movement of the hyoid bone following the mandibular setback surgery, returned near to its preoperative position after 1 year, postoperatively.

Management of Temporomandibular Joint Ankylosis Using Temporoparietal Fascia Flap.

The adhesion of mandibular condyle to the glenoid fossa by bone or fibroblastic tissue is called temporomandibular joint (TMJ) ankylosis. Trauma and infection are the main reasons for affecting TMJ ankylosis. TMJ arthroplasty is the treatment of choice for this situation. This study was aimed at reporting a new technique for the treatment of chronic TMJ ankylosis caused as a result of a car accident in patients who referred to Ghaem Teaching Hospital, Mashhad, Iran. The primary Maximum Mouth Opening (MMO) of the patient was equal to 2.5 mm. Interpositional arthroplasty was done using Temporoparietal Fascia Flap (TPFF) based on the superficial temporal artery. The MMO was increased to 35 mm after regular post-operative physiotherapy and a one-year follow-up. There was no sign of reanykylosis during this time. Interpositional arthroplasty using TPFF could be an appropriate treatment option. TPFF is thin and has a reliable blood supply. It seems that TPFF has less complication compared to other Interpositional materials like temporalis muscle flap.

The Effect of Bimaxillary Orthognathic Surgery on Nasalance, Articulation Errors, and Speech Intelligibility in Skeletal Class III Deformity Patients.

BACKGROUND: We aimed to detect the changes in nasalance, articulation errors, and speech intelligibility after bimaxillary orthognathic surgery in skeletal class III patients. METHODS: This double-blinded before and after quasi-experimental study was conducted in the Department of Maxillofacial Surgery, Qaem Hospital, Mashhad, Iran from Mar 2019 to Apr 2020. The main intervention was maxillary advancement with LeFort I osteotomy and mandibular setback surgery with bilateral sagittal split osteotomy (BSSO). The nasalance score, speech intelligibility, and articulation errors were evaluated one week preoperatively (T0), 1 and 6 months (T1, T2) postoperatively by a speech therapist. The significance level was set at 0.05 using SPSS 21. RESULTS: Eleven women (55%) and 9 men (45%) with a mean age of 31.95 ± 4.72 yr were enrolled. The mean maxillomandibular discrepancy was 6.15 ± 1.53 mm. The mean scores of nasalance for the oral, nasal, and oral-nasal sentences were significantly improved postoperatively (P<0.001). Pre-operative articulation errors of consonants /r/, /z/, /s/ and /sh/ were corrected following the surgery. The percentage of speech intelligibility was significantly increased over time (P<0.001). CONCLUSION: The patients might show a normal articulation pattern and a modified nasalance feature, following maxillary advancement plus mandibular setback surgery.

Does the Presence of Impacted Mandibular Third Molars Increase the Risk of Bad Split Incidence During Bilateral Sagittal Split Osteotomy?

BACKGROUND: The possibility of mandibular bad spilt might happen during bilateral sagittal split osteotomy (BSSO). This study investigated the effect of impacted mandibular third molars on bad spilt incidence during BSSO. METHODS: Totally, 140 patients under 40 years old who were candidates for BSSO surgery due to class 3 skeletal discrepancy were divided randomly into two equal groups. The impacted mandibular third molars were presented in one group during BSSO (Exposed), and the third molars were removed at least six months before surgery for the other group (Unexposed). All cases underwent BSSO using the same technique by a single surgeon. A bad split was diagnosed by inter-operative clinical examination and postoperative panoramic radiography. RESULTS: Four bad split occurrences were observed including three patients in the group which impacted mandibular third molars were presented and one patient in the group without impacted mandibular third molars. The incidence of bad fracture in the exposed group was 3.7 times more than the unexposed group. The incidence of the bad fracture in exposed group was 3.7 times more than unexposed group. The chance of fractures in females was 1.7 times higher than males. With one year addition to the patient's age, chance of fracture increased 0.985 times more. CONCLUSION: Overall incidence of bad split fracture in presence of mandibular third molars in females and at older ages increased during BSSO. The extraction of impacted mandibular third molars, six months before the BSSO is recommended to prevent the bad split incidence during the operation.

Medication-Related Osteonecrosis of the Jaw (MRONJ) due to Simvastatin: An Unusual Case Report.

Medication-related osteonecrosis of the jaw (MRONJ) is a serious pathological condition that usually results from anti-resorptive or anti-angiogenic drugs. We aimed to report an unusual MRONJ in a female patient due to long-term simvastatin administration. A 48-year female was referred to the Department of Oral and Maxillofacial, Mashhad Dental School, Mashhad, Iran in Dec 2019. She complained of pain, swelling, and infection in the right mandibular area with a history of extraction. Based on medical history, the patient received 40 mg of simvastatin daily for ten years to control hypercholesterolemia. According to clinical and radiographic examinations, as well as previous medical and dental records, the lesion diagnosis was detected as MRONJ. Moreover, histopathological examination of the lesion confirmed our clinical diagnosis. The necrotic bone was removed with caution. The PRF was then inserted, and the flap was sutured without any tension. No complications were observed on following-up, and all symptoms were discontinued. There was a correlation between the administration of high-dose simvastatin and MRONJ. Moreover, more clinical investigation with larger sample sizes is suggested.

The Effect of Bimaxillary Orthognathic Surgery on Voice Characteristics in Skeletal Class 3 Deformity Patients: An Evaluation Using Acoustic Analysis.

ABSTRACT: The aim of this study was to analyze the effects of bimaxillary orthognathic surgery on the acoustic voice characteristics of skeletal class 3 patients. All healthy nonsyndromic patients with Class 3 deformity who were eligible for bimaxillary orthognathic surgery, were included in this before and after quasi-experimental study. This experiment's main intervention was mandibular setback surgery by bilateral sagittal split osteotomy plus maxillary advancement using LeFort 1 osteotomy. Age, sex, and intraoperative jaw movements were recorded. Acoustic analysis of voice samples (vowels /a/ and /i/) was performed with Praat software as outcome variables. The formant frequencies (F0, F1, F2, and F3) of these vowels were extracted 1 week preoperatively (T0), 1 and 6 months (T1, T2) postoperatively by a speech therapist. The significance level was set at 0.05 using SPSS 19. The study sample comprised 20 patients including 11 women (55%) and 9 men (45%) with a mean age of 31.95 ±â€Š4.72 years. The average mandibular setback and maxillary advancement were 3.30 ±â€Š0.86 and 2.85 ±â€Š0.74 mm, respectively. The fundamental frequency (F0) and the first, second, and third formants (F1, F2, F3) of vowels /i/ and /a/ were significantly decreased over time intervals, postoperatively (P < 0.05). The finding revealed that bimaxillary orthognathic surgery (maxillary advancement and mandibular setback with bilateral sagittal split osteotomy) might reduce the acoustic formant parameters of voice to the normal frequency ranges, in patients with class 3 skeletal deformities. More clinical trials with greater sample sizes and long-term follow-ups are suggested in the future.

Is Preoperative Administration of Tranexamic Acid Effective on Blood Loss Reduction in Mandibular Fracture Surgeries? A Triple-Blind Randomized Clinical Trial.

PURPOSE: Hemorrhage is one of the significant factors that cause adverse reactions and complications during trauma management. This study aimed to investigate the effectiveness of preoperative tranexamic acid (TXA) administration on intraoperative blood loss in mandibular fracture surgeries. MATERIALS AND METHODS: The authors implemented a triple blinded randomized clinical trial. All healthy young patients who suffered from bilateral displaced mandibular angle and body fractures were included in this study. All operations were performed using open reduction and internal fixation by the same surgical team. The eligible subjects were randomly divided into 2 equal groups. The anesthesiology staff administered the intravenous TXA (20 mg/kg) to the intervention group and 20 mL of intravenous normal saline (0.09%) in the control group, 30 minutes preoperatively. The study outcome variables included intraoperative blood loss and hemoglobin loss. The data were statistically analyzed in SPSS, version 20 (SPSS Inc, Chicago, IL). RESULTS: Fifty patients, including 31 males (62%) and 19 females (38%), with the mean age of 28 ± 5.6 years were studied. The mean blood loss was 360.57 ± 173.5 mL and 560.9 ± 248.07 mL in the TXA and control groups, respectively. This difference was statistically significant (P = .008). In addition, the mean drop in hemoglobin value was 0.91 ± 0.33 mg/dL in the intervention group and 1.44 ± 0.45 mg/dL in the control group, with a significant difference (P = .001). No adverse effect was observed in the TXA cases. CONCLUSIONS: TXA is a safe and effective drug for reducing intraoperative blood loss in patients who underwent mandibular fracture open reduction and internal fixation surgeries.

Is There an Increase in the Risk of Obstructive Sleep Apnea After Isolated Mandibular Setback Surgery? An Evaluation Using the STOP-BANG Questionnaire.

PURPOSE: The aim of this study was to assess the impact of isolated mandibular setback surgery on the risk of obstructive sleep apnea (OSA), using the STOP-BANG questionnaire (SBQ). PATIENTS AND METHODS: The authors implemented a double-blinded prospective quasi-experimental study. All healthy patients with skeletal Class III deformity older than 18 years were included in this study. They were candidates for isolated mandibular setback surgery. The SBQ was completed by the pulmonologist, 1 week preoperatively (T0), and 1 and 6 months postoperatively (T1 and T2, respectively). The mandibular setback displacement was the study intervention. The risk of OSA on the basis of the SBQ was the outcome variable. Descriptive and bivariate statistics were computed and the significance level was set at .05. RESULTS: The sample comprised 30 patients (15 females, 15 males) with the average age of 25.77 ± 4.76. The mean score of SBQ at T0 was 1.37 ± 0.85, which increased to 2.33 ± 1.52 at T1 interval. However, it decreased significantly to 1.47 ± 1.17 at T2 interval (P < .001). T0-T1 and T0-T2 score differences were observed to be higher in the group with a mandibular setback repositioning greater than or equal to 5 mm (P < .005). CONCLUSIONS: An isolated mandibular setback surgery less than 5 mm does not increase the risk for OSA in a young healthy nonsmoker Class III patient, according to the SBQ. Moreover, there was a significant increase in the risk for OSA when the setback was greater than or equal to 5 mm, measured at the mandibular incisor edge. Therefore, clinicians should be careful and discuss this potential increased risk with the patients, when this movement is required by the treatment plan. Further clinical trials are needed to support the relevancy.

A study on PEI among private dentists in Mashhad, Iran.

AIM: We aimed to identify the percutaneous exposure incident (PEI) by private dentists in Mashhad, Iran. METHODS: Subjects included 199 dentists enrolled in this study. A questionnaire consisting of 11 questions was sent to the dentists for data collection. Information was collected on knowledge about dangers of PEI, a history of needlestick or sharps injuries over the past 12 months, types of devices causing the needlestick or sharps injuries, HBV vaccination, knowledge about PEI protective and therapeutic protocol, and reporting PEI to the specialist. The first ten questions were corrected and each sheet received a score ranging from 0 to 10. RESULT: 95 women (47.7%) and 104 men (52.3%) participated in this study aged between 27-72 years old. The findings showed that a total of 132 dentists (66.3%) had experiences with PEI. 45 (22.6%) of them had experiences with PEI in the past year. Files and needles were found to be the most frequent tools causing PEI, each with 29.7% of frequency. 16.6%, 8.6, 5.7, and 9.7% were obtained for dental burs, band, and surgical baled, respectively as other tools responsible for injuries. Results of the question about causes of needlestick injuries showed that personal carelessness is the most frequent reason (53.8%) followed by inappropriate disposal of the needles (7.6%). CONCLUSION: The personal carelessness and inappropriate disposal of needles were reported as the most common reasons for PEI injuries. It is suggested to educational programs for dentists should focus on preventing the PEI.