Post-BSSO condylar position stability: a comparison of miniplate and lag screw fixation.

BACKGROUND: This study was conceived to assess the postoperative stability of condylar position following fixation with miniplates and lag screws after bilateral sagittal split osteotomy (BSSO). METHODS: This retrospective study included a cohort of 20 patients undergoing BSSO using the Obwegeser-Dal Pont modification. The bony segments were stabilized using either miniplates with two 2.0-mm monocortical screws per segment or three 2.0-mm bicortical lag screws along the mandible's superior border. Pre- and postoperative (7-day interval) spiral computed tomography scans were conducted to assess skeletal changes across both groups. Data analysis employed Wilcoxon signed-rank and Wilcoxon rank-sum tests (α = 0.05). RESULTS: No statistically significant difference was observed between the pre-and postoperative condylar position parameters (P>0.05). However, the lag screw group showed a marginal significant increase in the left condyle's angulation (preoperative: 24.83 ± 6.37 vs. postoperative: 32.5 ± 4.93; P = 0.04). Changes in condylar height, length, and width were not statistically significant before and after BSSO in either groups (P>0.05). Nor was any statistically significant difference found between the miniplates and lag screws groups regarding condylar position parameters (P>0.05). CONCLUSION: The results indicated that both lag screw and miniplate fixation methods can be effectively employed in BSSO procedures without impacting condylar position parameters. Thus, either fixation method can be chosen depending on factors such as the surgeon's preference and clinical outcomes.

Carcinogenic effects of heavy metals by inducing dysregulation of microRNAs: A review.

Heavy metal exposure has soared due to the twentieth century's industrial activity. The most common heavy metals that lead to human poisoning are mercury, cadmium, and arsenic. Acute or chronic poisoning may develop following exposure to water, air, or food, so the bioaccumulation of these heavy metals causes harmful consequences in various human tissues and organs. Heavy metals interfere with biological functions such as growth, proliferation, differentiation, damage repair, and apoptosis. The mechanisms of action for these metals to cause toxicity are similar, including forming reactive oxygen species (ROS), weakening antioxidant defenses, enzyme inactivation, and oxidative stress. Heavy metal exposure is mainly associated with skin, liver, prostate, lung, urinary bladder, thyroid, and kidney cancers, as well as causing gastrointestinal malignancies. Several microRNAs (miRNAs or miRs) have been involved in various human cancers due to the dysregulation of miRNA function. Recent investigations have confirmed that microRNA dysregulation plays a role in the carcinogenesis of many tissues. This review presents the data concerning arsenic, cadmium, and mercury metals and their contamination sources, human exposure, toxicity, and inducing malignant transformations such as carcinogenicity in in-vitro or in-vivo specimens or dysregulated expression of microRNAs.

Marginal bone resorption of posterior mandible dental implants with different insertion methods.

BACKGROUND: To evaluated the marginal bone loss around dental implants by two insertion methods. METHODS: Eligible patients were divided into two groups; manual and mechanized groups. Peri-apical x-ray using a customized device to standardize the radiographs designed and used to take three periodical radiographs; after surgery, three months, and six months follow up. An independent t-test was used to compare the two groups regarding the average level of marginal bone loss (p < 0.05). RESULTS: After excluding dropouts, a total of 273 patients (120 males and 153 females, aged between 25 and 67 years old) were included in the study. The average marginal bone loss in the manual insertion method was 0.44 ± 0.84 mm, and 0.59 ± 0.20 mm, and for the mechanized method was 0.51 ± 0.20 mm and 0.67 ± 0.19 mm after three and six months, respectively. There was a significant difference in marginal bone loss after six months between the two groups(p < 0.001). However, no differences were observed after three months (p = 0.24). CONCLUSIONS: Under the condition of this study, both techniques were safe and resulted in an acceptable amount of bone resorption; however, in the manual method, the less marginal bone loss occurred after six months.

Evaluation of the Possible Synergic Regenerative Effects of Platelet-Rich Plasma and Hydroxyapatite/Zirconia in the Rabbit Mandible Defect Model.

BACKGROUND: Platelet-rich plasma (PRP) and bioceramics such as hydroxyapatite (HA) and zirconium oxide (ZrO2) are used to reconstruct mandibular defects. We sought to determine the synergistic effects of HA/ZrO2 and PRP and compare their osteogenic activity. METHODS: ZrO2 scaffolds were constructed by the slurry method and were then coated with HA and impregnated by PRP/heparan sulfate (HS). Bilateral mandibular defects were created in 26 male rabbits. In 20 rabbits, the left defects were treated with HA/ZrO2/PRP (Group 1) and the corresponding right defects were filled with HA/ZrO2 (Group 2). The 6 remaining models were treated with PRP gels at both sides (Group 3). The osteoconductivity of HA/ZrO2/PRP was compared with that of HA/ZrO2 or PRP by radiological and histological methods after the follow-up period, at weeks 2, 6 and 8. The statistical analyses were performed by ANOVA and LSD using SPSS, version 16.0, for Windows (P<0.05). RESULTS: After 2 weeks, the percentage of the surface occupied by bone was significantly higher in the HA/ZrO2/PRP-treated defects than in the PRP-treated defects (P=0.007). Osteoblast and osteocyte counts were higher significantly in the PRP-treated group (P=0.032); however, the cells had not started matrix formation on a large scale and just small islands of osteoid with trapped osteocytes were observed. In the long term, the regenerative potential of all the scaffolds was the same. CONCLUSION: HA/ZrO2 showed a superior osteoconductive capacity over PRP in the short term; however, they showed no long-term synergic effects.

Does gum chewing increase the prevalence of temporomandibular disorders in individuals with gum chewing habits?

PURPOSE: The effect of habitual gum chewing on temporomandibular joint function is controversial. This study evaluated the prevalence of temporomandibular disorder (TMD) in adolescents with and without gum chewing habits and the affiliation of TMD signs with gum chewing. SUBJECTS AND METHODS: This is a cross-sectional study. Subjects were studied in 2 groups. Subjects in the study group chewed gum for 30, 60, or 120 minutes in a 24-hour day. Subjects in the control group did not have a gum chewing habit. TMD signs of clicking, crepitus, and pain were documented for every subject. Age, gender, duration of gum chewing, and occlusal relationships were variable factors, and TMD signs (clicking, crepitus, and pain) were outcomes of the study. The chi-square test was used to compare TMD signs and gender in the 2 groups, and to evaluate the relationship between TMD signs and duration of gum chewing in the study group. An independent t test was applied to compare the ages of the 2 groups. RESULTS: Two hundred subjects participated in the study and were divided into 2 groups (100 subjects per group). An evaluation of the data showed no significant differences between the 2 groups in sex, age, and occlusion. The incidence of clicking and pain was statistically higher in the study group than in the control group (P < 0.05). Analysis of the data demonstrated considerable differences in clicking and pain among subjects with various gum chewing times in the study group (P < 0.05). The incidence of pain was higher in subjects with a class II skeletal pattern than others in the study group (P < 0.001). Nevertheless, no significant difference was noticed for clicking among subjects with various occlusions (P > 0.05). CONCLUSION: Considering that intensive gum chewing may affect TMD signs in individuals with a gum chewing habit. It seems a longer duration of gum chewing may increase the prevalence of TMD. Individuals with a class II skeletal pattern may be affected more than others.

Comparison of nonsurgical treatment options in pediatric condylar fractures: rigid intermaxillary fixation versus using guiding elastic therapy.

A prospective study was done to compare rigid intermaxillary fixation and guiding elastic for treatment of condylar fractures in pediatric patients. Sixty-one children younger than 12 years with condylar fractures were studied in 2 groups. Group 1 consisted of 31 patients who were treated with arch bar and intermaxillary fixation for 7 to 12 days, and group 2 consisted of 30 patients who were treated with arch bar and elastics without rigid intermaxillary fixation. Patients had minimal function during treatment time, which lasted 7 to 12 days. Evaluation of deviation on opening between both groups (groups 1 and 2) with a χ test did not show any relationship between them. Incidence of temporomandibular dysfunction signs was 25.8% in group 1 patients and 23.3% in group 2 patients. Comparison of temporomandibular dysfunction signs in both treatment groups did not show a statistically significant relationship. Our study showed the same results using guiding elastics as using rigid intermaxillary fixation in pediatric condylar fractures. Guiding elastic is more tolerable, and children have function during treatment.

Detection of Circulating Cell-Free DNA to Diagnose Hepatocellular Carcinoma in Chinese Population: A Systematic Review and Meta-Analysis.

BACKGROUND: Cell-free circulating DNA has been known for many years, but this knowledge has not been beneficial for diagnosis. In this meta-analysis, we examine the diagnostic role of circulating cell-free DNA in HCC patients to find a reliable biomarker for the early detection of HCC. MATERIALS AND METHODS: We performed a systematic literature search using Science Direct, Web of Science, PubMed/Medline, Scopus, Google Scholar, and Embase, up to April 1st, 2022. Meta-Disc V.1.4 and Comprehensive Meta-Analysis V.3.3 software calculated the pooled specificity, sensitivity, area under the curve (AUC), diagnostic odds ratio (DOR), positive likelihood ratio (PLR), negative likelihood ratio (NLR) Q*index, and summary receiver-operating characteristic (SROC) for the role of cfDNA as a biomarker for HCC patients. Moreover, the subgroup analyses have been performed based on sample types (serum/plasma) and detection methods (MS-PCR/methylation). RESULTS: A total of 7 articles (9 studies) included 697 participants (485 cases and 212 controls). The overall pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), and area under the curve (AUC) were 0.706 (95% CI: 0.671 - 0.739), 0.905 (95% CI: 0.865 - 0.937), 6.66 (95% CI: 4.36 - 10.18), 0.287 (95% CI: 0.185 - 0.445), 28.40 (95% CI: 13.01 - 62.0), and 0.93, respectively. We conducted a subgroup analysis of diagnostic value, which showed that the plasma sample had a better diagnostic value compared to the serum. CONCLUSION: This meta-analysis showed that cfDNA could be a fair biomarker for diagnosing HCC patients.

Blood-based microRNAs as Potential Diagnostic biomarkers for Melanoma: A Meta-analysis.

INTRODUCTION: Circulating microRNAs (miRNAs) serve as noninvasive diagnostic markers in many cancers. This meta-analysis aims to evaluate the diagnostic efficacy of circulating microRNAs for melanoma. MATERIAL AND METHODS: The pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio, and ROC curve were evaluated using the Meta-Disc V.1.4 and Comprehensive Meta-Analysis V.3.3 software packages. To investigate the heterogeneity, the I2 and Chi-square tests were used. The publishing bias was evaluated using Begg's rank correlation and Egger regression asymmetry tests. RESULTS: A total of 9 articles covering 13 studies (more than 50 miRs individually and in combination) were included, containing 1,355 participants (878 cases and 477 controls). The overall pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio (DOR), and AUC were 0.78 (95% CI: 0.76-0.81), 0.80 (95% CI: 0.77-0.83), 4.32 (95% CI: 3.21-5.82), 0.17 (95% CI: 0.09-0.32), 28.0 (95% CI: 15.34-51.09), and 0.91, respectively. According to Begg's and Egger's tests, there was no publication bias (Begg's p = 0.160 and Egger's p = 0.289). CONCLUSION: Circulating miRNAs can serve as fair and non-invasive diagnostic biomarkers for melanoma. Additionally, specific miRNAs still need to be discovered for diagnosing melanoma.

Clinical, CT scan, and laboratory changes of abscess patients with odontogenic origin admitted to Shiraz acute surgical care center, Iran.

INTRODUCTION: Rapid diagnosis of maxillofacial abscess with the odontogenic origin is effective in the treatment of patients. This study aimed to check the clinical evaluation, head, and neck computed tomography (CT) scan, and microbial sensitivity of hospitalized patients diagnosed with maxillofacial abscess admitted to the Maxillofacial Surgery Ward Shaheed Rajaie Surgical Acute Care Center of Shiraz, Iran from 2019-2021. METHOD: A cross-sectional study was conducted. The sample included patients diagnosed with the abscess of odontogenic origin. Data collection tools included personal profile registration form, chief complainant and clinical evaluation, laboratory test results, pus culture, antibiogram results, and head and neck CT scan changes form. Data was reported with descriptive statistics by SPSS-16 software. RESULTS: The majority of patients were male; infection duration was 10 days; maximum mouth opening size was less than 20 mm in more than half of patients. The scan revealed 41.8% abscess, 36.4% cellulite, and 21.8% mixed abscess and cellulitis. There was 29.1% involvement of salivary glands. The majority of abscesses were unifocal involved in the submandibular space, and the least involvement was in peri mandibular space and carotid sheath. The most common organism causing was staphylococcal abscess coagulase-negative. CONCLUSION: In patients with maxillofacial abscess requiring hospitalization, the most common clinical features were trismus, toxic appearance, and dysphagia, and the most common source of abscess in scanning patients with mandibular molars was the most involved submandibular space and pterygomandibular space. Vancomycin, cotrimoxazole, and cefazolin had the greatest effect in the treatment of odontogenic infections in terms of antibiogram results and microbial culture.

Evaluation of bite force recovery in patients with maxillofacial fracture.

The aim of this study was to measure the maximum voluntary bite force and recovery time in patients treated for different types of the maxillofacial fracture. Patients aged between 18 and 60 years, who received surgical treatment for a single isolated fracture of the maxillofacial structure, were included in this study. Healthy individuals without any maxillofacial abnormality were selected as the control group. Bite force (in kg) was measured at the first incisor tooth, bilaterally, prior to surgery and 2 weeks, 6 weeks, 3 months, and 6 months after surgery. Of 120 patients, 89 (74.17%) were male and 31 (25.83%) were female. Mean patient age (±SD) was 31.21 (±11.64) years. Bite forces relating to fractures of the zygomaticomaxillary complex (ZMC) with involvement of the arch and zygomaticofrontal suture reached normal levels after 6 weeks (from 3.89 (±1.11) to 10.82 (±1.29); p = 0.296 and from 4.20 (±0.93) to 10.70 (±1.70); p = 0.192, respectively). Bite force returned to normal after 3 months in fractures of the symphysis (from 2.05 (±0.97) to 12.18 (±0.77); p = 0.222), body (from 2.21 (±1.26) to 11.9 (±0.73); p = 0.750), angle (from 2.45 (±1.24) to 11.89 (±0.76); p = 0.769), condyle (from 2.45 (±1.27) to 11.25 (±0.82); p = 0.968), and ZMC with and without infraorbital rim involvement (from 3.83 (±0.93) to 11.92 (±0.84); p = 0.724 and from 3.7 (±1.21) to 12.03 (±0.82); p = 0.482, respectively). Patients with ZMC fracture involving the arch and zygomaticofrontal suture require fewer follow-ups in comparison with those with other maxillofacial fractures. Measurement of maximal bite force can help to evaluate dentofacial deformities before and after surgical treatment.

Changes in Blood Pressure and Pulse Rate of Patients without Systemic Diseases Following the Injection of 2% Lidocaine Plus Epinephrine 1:80000 in an Inferior Alveolar Nerve Block - A Prospective Study.

INTRODUCTION: An inferior alveolar nerve block is dental anesthesia produced by the local injection of lidocaine plus epinephrine; however, its administration could cause cardiovascular side effects. We aimed to assess the changes in blood pressure and pulse rate following the injection of 2% lidocaine with epinephrine 1:80000 for an inferior alveolar nerve block. MATERIALS AND METHODS: Seventy-one patients without any systemic disease were enrolled in this study. Systolic blood pressure (SBP), diastolic blood pressure (DBP), and pulse rate were measured using an automatic digital blood pressure monitor in four stages as follows: at the rest time (Stage 1), prior to injection (Stage 2), immediately after injection (Stage 3), and 10 min after the administration of anesthetic agents (Stage 4). All injections and measurements were carried out by a single operator to minimize the variability. RESULTS: SBP and DBP in all stages were within the normal range (lower than 130 and 80 mmHg, respectively), and none of the patients showed evidence of arterial hypertension. Although the pulse rate increased significantly at Stages 2, 3, and 4 compared with Stage 1 (P < 0.05), no evidence of bradycardia or tachycardia was seen. DISCUSSION: Local anesthesia with 2% lidocaine plus epinephrine 1:80000 for an inferior alveolar nerve block would be safe for patients without any systemic diseases.

Intraoperative Blood Loss in Maxillofacial Trauma Surgery.

BACKGROUND AND OBJECTIVES: This study is aimed to assess the intraoperative blood loss of patients with maxillofacial bone fracture surgical intervention and to assess their need for blood transfusion. MATERIALS AND METHODS: In this retrospective study, intraoperative blood loss of 206 patients with facial bone fractures, who underwent surgery between 2017 and 2018, was retrieved. The patient's demographic information, the amount of blood loss, the type of facial bone fracture, and the patient's requirement for blood products were evaluated. RESULTS: The average amount of intraoperative blood loss was 77.6 ml, and none of the patients required a blood transfusion during the operation in this group of patients. maxillofacial bone fracture was most common in young males. The leading cause of fractures was motor vehicle accident. There was a reverse correlation between the patient's age and surgical blood loss, but there was no statistically significant relationship between the patient's gender and intraoperative surgical blood loss. CONCLUSION: The results of the present study show that preparation for blood transfusion in patients with maxillofacial traumatic bone fracture requiring surgery is uncommon if patients have no systemic disease or specific blood dyscrasias preoperatively.

Effects of Different Storage Media, Temperature, and Time on Osteoblast Preservation in Autogenous Bone Grafts: A Histomorphometrical Analysis.

STATEMENT OF THE PROBLEM: Autogenous bone graft is the gold standard for bone reconstruction. Osteogenic cells must be kept viable in graft for a successful procedure. In extracorporeal preservation of grafts during surgery, three different factors may influence the quality of grafts. These factors include temperature, storage medium, and time interval. PURPOSE: In this study, we evaluated the effects of different storage media, temperatures, and times on osteoblast count in autogenous bone grafts, preserved extracorporeally. MATERIALS AND METHOD: Samples were obtained from iliac crest region in a goat. The grafts were preserved in 36 groups of different storage time, temperature, and medium. Samples were histomorphometrically analyzed to determine osteoblast count as the criteria of graft quality. RESULTS: In almost all samples, room temperature was the most and incubator was the least favorable storage temperatures. In grafts preserved in room temperature, no difference was noted between normal saline and Ringer's lactate solution and in almost all of the samples autologous blood and dry environment were more favorable media than Ringer's lactate solution. The effect of storage time was highly depended on the combination of temperature and solution. CONCLUSION: The results demonstrated that for preserving as many osteoblasts as possible in bone grafts, the best temperature was room temperature and the least favorable temperature was incubator. In addition, when bone fragments were preserved in room temperature, the best medium for graft storage was blood, which showed better results than normal saline and Ringer's lactate solution.

The LncRNA H19 rs217727 Polymorphism Is Associated with Oral Squamous Cell Carcinoma Susceptibility in Iranian Population.

Lack of protein-coding capacity is a main characteristic of long noncoding RNAs (lncRNAs) which, as molecular biomarkers, have found a novel pharmacological application in cancer and are reported to be important regulators of gene expression. H19 is reportedly involved in cancer progression and tumorigenesis. One of the most common types of head and neck cancers is oral squamous cell carcinoma (OSCC). The main objective of the present study was to evaluate the correlation of OSCC susceptibility with H19 gene in an Iranian population. This research was performed on 400 subjects of both sexes referred to the Namazi Hospital affiliated with the Shiraz University of Medical Sciences (SUMS). Individuals aged 15-88 years were divided into two groups: pathologically diagnosed patients with new-onset OSCC and healthy controls. After written and informed consent was obtained from the individuals, genomic DNA was extracted. The tetra-primer ARMS-PCR technique was performed for DNA genotyping by the use of specific primer pairs. The susceptibility of OSCC and H19 gene polymorphism sites was further analyzed (rs217727 and rs2107425). The allele and genotype frequencies of H19 rs2107425 polymorphism were similar between OSCC cases and controls. The H19 rs217727T allele frequency was significantly higher in OSCC cases (P = 0.002), and the polymorphism of H19 rs217727 was associated with OSCC susceptibility in the codominant (OR = 6.04, 95%CI = 1.70 - 21.42, P = 0.001 for TT genotype), dominant (OR = 1.62, 95%CI = 1.08 - 2.43, P = 0.01), and recessive (OR = 5.32, 95%CI = 1.51 - 18.69, P = 0.003) models. This study showed that rs217727 and OSCC susceptibility were statistically correlated in the Iranian population.

Skeletal stability following mandibular advancement: is it influenced by the magnitude of advancement or changes of the mandibular plane angle?

OBJECTIVES: The aim of this study was to investigate the effects of advancement magnitude and changes in mandibular plane angle on the stability of mandibular advancement. MATERIALS AND METHODS: This retrospective cohort study evaluated the postoperative stability of mandibular advancement in class II skeletal subjects who underwent bilateral sagittal split osteotomy. Radiographs taken preoperatively, immediately postoperatively and 1 year postoperatively were traced and analyzed using linear and angular measurements. To determine horizontal and vertical relapse, an X-Y coordinate system was established in which the X-axis was constructed by rotating S-N downward by 7° (approximation of the Frankfort horizontal plane) and the Y-axis was defined as a line perpendicular to the X-axis and passing through the point Sella. For certain reference points including point A, point B, pogonion and menton, the perpendicular distance between each point and both axes was determined and cephalometric variables were recorded as X and Y coordinates. RESULTS: Twenty-five subjects were studied. A significant correlation between the amount of mandibular advancement and relapse in the B point (vertical and horizontal) and the pogonion point was observed (vertical and horizontal, P<0.001). Evaluation of data demonstrated a positive correlation between the mandibular plane angle (SN/ML) change and vertical relapse in the B point (P<0.05). A simple regression model demonstrated that 74% of horizontal relapse and 42.3% of vertical relapse in the B point was related to the amount of mandibular advancement. The receiver operating characteristic test showed that 8.5 mm mandibular advancement is related to a relapse rate of 1 mm or more in the pogonion, vertically or horizontally. CONCLUSION: The magnitude of mandibular advancement is a stronger surgical predictor for horizontal rather than vertical relapse at the B point. Changes in mandibular plane angle (SN/ML) during surgery affect vertical, but not horizontal relapse at the B point.

Does increasing the number of short implants reduce marginal bone loss in the posterior mandible? A prospective study.

Marginal bone loss is a concern in the long-term prognosis of short dental implants. The aim of this prospective cohort study was to evaluate the loss when variable numbers of short implants were used in the posterior mandible. The subjects were allocated into three groups according to the number of short implants. The first group was given two, the second three, and the third four. Each patient had radiographs taken immediately after loading and repeated 36 months later. Twenty- three subjects with 65 implants were entered in the three groups. The mean (SD) marginal bone loss was 0.49 (0.04) mm in the two implant group, 0.41 (0.25) mm in the three implant group, and 0.35 (0.25) mm in the four implant group. There were significant differences in marginal bone loss among the three groups (p=0.001), in that the fewer the number of short implant-supported fixed prostheses in the posterior mandible, the greater the marginal bone loss. When we used more short implants the amount of marginal bone loss decreased.

Association between clinical features, treatment, and recurrence rate of adenoid cystic carcinoma of the palate: a 10-year retrospective study.

Adenoid cystic carcinoma (ACC) is both invasive and clinically unpredictable, and our aim was to evaluate the factors that affect its recurrence in the palate. We retrospectively studied 38 patients who had ACC of the palate treated surgically, and the outcome measure was recurrence during the mean (SD) followup time of 55 (18) months. Age, sex, T-stage, bony involvement, duration of follow up, histological type, perineural invasion, and surgical margins were all recorded. Results showed no association between recurrence, and age or histopathological types. However, T-stage (p=0.001), sex (p=0.04), and bony and perineural involvement (p=0.01 in each case) were significantly associated with recurrent tumour. Close superior and posterior margins (< 2mm) were also associated with recurrence (p=0.001 in each case). Large tumours with bony and perineural involvement, together with close superior and posterior surgical margins, had a higher risk of recurrence.