Extracorporeal Shock Wave Therapy as a Helpful Method for Rapid Osseointegration of Dental Implants: Animal Study.

The aim of this study was to assess the multi-phasic use of extracorporeal shock wave therapy (ESWT) as an adjuvant treatment to accelerate the osseointegration of titanium dental implants. Initially, twelve titanium mini-screws were inserted in femur bones of six New Zealand rabbits in three groups; the one-time treated group, the three-time treated group, and the control group (without ESWT). Then, 1800 focused shockwaves with an energy flux density of 0.3 mJ/mm2 in every phase were used. Fourteen days after the last phase of ESWT, the animals were sacrificed to assess the osseointegration of screws via micro-computed tomography scan (micro-CT scan), biomechanical pull-out test, and histopathological analysis. Pull-out and histopathology analysis showed that the ESWT significantly increased bone regeneration and osseointegration around the implants compared to the control group (p < 0.05). Moreover, the pull-out test confirmed that the three-time treated screws needed more force to pull the bone out compared to the other two groups (p < 0.05). The mean bone volume fraction between the control group, the one-time treated group, and the three-time treatment group were not statistically significant (p > 0.05) according to the micro-CT scan results. Based on our results, ESWT can be suggested as a non-invasive and cost-effective adjuvant for osseointegration of dental implants. However, more in vivo studies and clinical trials are needed for validation of this finding.

Evaluation of bone regeneration in mandible large defect using undifferentiated adipose stem cells loaded on gelatin carrier: An animal model case study.

Background. Large mandibular defects are considered difficult reconstructive challenges for oral and maxillofacial surgeons. Cell therapy, as an alternative technique, might increase the speed of bone regeneration. This study aimed to investigate bone regeneration in large defects of dog mandibles using allogenic adipose-derived stem cells on gelatin foam as a cell carrier. Methods. The tissue engineering phase consisted of the sampling of adult dogs' adipose tissue that can easily be isolated from adipose stem cells (ASCs) of the dogs, ASCs were cultured in Dulbecco's Modified Eagle's Medium (DMEM, Gibco, USA) with low glucose, containing 10% fetal bovine serum (FBS) (Sigma, USA) and 1% penicillin-streptomycin (Gibco, USA), with the characterization of dog ASCs and gelatin-transplanted ASCs. Six dogs were included in this experimental study in the next step and randomly assigned to the treatment and control groups. The samples in both groups underwent surgery under general anesthesia to create uniform 3-cm bony defects. The samples in both groups were reconstructed with titanium reconstruction plates and screws. A large bone gap filled with ASCs (5×106 ) was seeded on gelatin (ASCs) in the treatment group. In the control group, bony defects were filled with a cell delivery carrier without ASCs. Six months after transplantation, the animals' mandibles were evaluated by CT scan imaging, and the results were quantified through the Hounsfield unit (HU). The data were analyzed with t-test. Results. Before transplantation, the nature of the stem cells was confirmed by the expression of CD44 and CD105 cell markers at 71.9% and 89.3%, respectively, and a lack of the CD45 cell marker expression at 2.2%. Evaluation of CT scan images showed significantly higher bone repair in the ASCs group (920.25±572.92 HU) than in the control group (-94.746± 08.42). Conclusion. The bone regeneration of the ASCs group was significantly higher than that in the control group.

Evaluating the role of microRNAs alterations in oral squamous cell carcinoma.

Oral squamous cell carcinoma (OSCC) accounts for nearly 90 percent of oral cavity malignancies and is one of the most widespread oral cancers in the world. The microRNAs (miRNAs or miRs) have an important role in cellular processes comprising cell cycle, differentiation, and also apoptosis. MiRNAs are also implicated in the progression of cancers, including OSCC, through a variety of signaling pathways. One of the most significant signaling pathways in OSCC is the PI3K / Akt pathway that has been illustrated to be under the tight regulation of miRNAs. Deregulation or activation of the PI3K / Akt pathway due to mutations has been revealed to be implicated in the development of oral cancer. According to studies, more than 47% of HNSCC and around 38% of OSCC samples indicate at least one molecular alteration in this signaling pathway. The potential of miRNAs for their use as therapeutic tools in the diagnosis as well as treatment of numerous diseases have been confirmed. In the current review, we summarize miRNAs and their possible mechanisms as well as their functions in OSCC advancement and progression.

Seven-year follow-up of spontaneous bone regeneration following segmental mandibulectomy: Alternative option for mandibular reconstruction.

Bone formation in small deposits following the loss of part of the mandible has often been reported in the literature, but the long-term follow-up reports of bone regeneration extending over the mandible are rare. Even rarer, are reports on the behavior of such new bone in terms of facial development, over a long period and the effect of load on it. A unique case of bone regeneration after resection of a large portion of the mandible in a 9-year-old male patient with myxofibrosarcoma in the body of the mandible is presented here. Intermaxillary fixation and insertion of reconstruction plate after resection without continuity defect were employed. Spontaneous bone regeneration was noted 8 weeks after surgery, and the resected portion of the mandible was regenerated when the patient was seen again 7 years later. Mandibular growth was not significantly affected and almost 7 years after his treatment, without relapsing of pathologic condition, the shape of the mandible is satisfactory without any evidence of bone resorption.

Transfection of microRNA-143 mimic could inhibit migration of HN-5 cells through down-regulating of metastatic genes.

Oral squamous cell cancer (OSCC) is one of the causes of death worldwide. The purpose of this project was to define the restoring of microRNA-143 in HN-5 cells and discover molecular apparatuses responsible for the anticancer processes. Firstly, expression levels of miR-143, K-Ras, MMP9 and C-Myc were evaluated in OSCC tissues. Then, microRNA-143 was transfected into HN-5 cells. The cytotoxic effects of microRNA-143 on HN-5 cells were evaluated. To estimate the effects of microRNA-143 on cell migration, wound healing assay was done. The expression levels of microRNA-143, K-Ras, MMP9, C-Myc, ADAMTS and CXCR4 were evaluated via the qRT-PCR method. microRNA-143 mimic inhibited cell migration in HN-5 cell line. microRNA-143 mimic decreased K-Ras, MMP9, C-My, ADAMTS and CXCR4 gene expression. microRNA-143 can inhibit HN-5 cells migration in vitro by down-regulating the expression of invasion-linked genes. Hence, microRNA-143 can be a new diagnostic biomarker and new therapeutic target for OSCC.

Secretory phospholipase-A2 and fatty acid composition in oral reactive lesions: a cross-sectional study.

BACKGROUND: Oral reactive lesions are the most common lesions of oral cavity. Phospholipases and fatty acids play key roles in the creation of inflammation by change in metabolic activities and production of lipid mediators. The aim of this study was to investigate the amount of secretory phospholipase-A2 (sPLA2) and difference of fatty acid pattern in oral reactive hyperplasia and adjacent normal appearing tissues in patients with oral reactive lesions. METHODS: Paired samples of oral hyperplastic (OH) and adjacent normal-appearing tissue of 45 patients were investigated in this study. The collected samples were analyzed with enzymatic spectrophotometric method in terms of the amount of sPLA2 and composition of fatty acids by gas-liquid chromatography method. RESULTS: The amount of sPLA2 (1.8-fold, p < 0.001), stearic acid (1.2-fold, p < 0.001), oleic acid (1.1-fold, p = 0.01), arachidonic acid (1.5-fold, p < 0.001) and docosahexaenoic acid (1.3-fold, p = 0.02) were increased, while the amount of palmitoleic acid (-45%, p < 0.001) and linoleic acid (-19%, p < 0.001) were reduced in the OH tissue samples. Furthermore, the results demonstrated significant associations between the type and location of tissue samples with monounsaturated fatty acids (MUFAs) and n-3 polyunsaturated fatty acids. Tissue samples from patients with inflammatory fibroepithelial hyperplasia showed relatively higher MUFAs and lower n-3 polyunsaturated fatty acids than other type of lesions. CONCLUSIONS: Localized changes in the sPLA2 activity and composition of fatty acid are associated with oral reactive hyperplasia and the type of pathological response. We suggest that sPLA2 activity and multiple type of fatty acids might be used as potential therapeutic target for oral reactive hyperplasia.

Effect of Preoperative Oral Amantadine on Acute and Chronic Postoperative Pain After Mandibular Fracture Surgery.

BACKGROUND: Postoperative pain from open reduction and internal fixation of mandibular fracture is a serious issue. Amantadine is an N-methyl-D-aspartic acid or N-methyl-D-aspartate (NMDA) receptor antagonist that can be effective against postoperative pain. OBJECTIVES: The present study examined the efficacy of amantadine in alleviating the postoperative pain of mandibular fracture surgery. PATIENTS AND METHODS: In this double-blind study, 60 patients (ASA physical status I-II) were randomly divided into two groups. The mean ages of the participants were 31.2 ± 13.1 years and 32.3 ± 18.1 years, respectively. The male/female ratios were 24/6 and 26/4, respectively, in the case and control groups. Randomization was based on a single sequence of random assignments using computer-generated random numbers. Group I was given oral amantadine 100 mg 1 hour before surgery, and group II received a placebo at the identical time. Through PCA pumps, patients received a bolus dose of morphine at 0.02 mg/kg body weight, to a maximum of 1.5 mg. PCA pumps were set at 6 minutes lockout intervals and a maximum dose of 0.15 mg/kg/h, to a maximum of 10 mg/h. Pain was assessed using a visual analog scale (VAS) at 0, 2, 4, 6, 12, and 24 hours and 1, 2, 3, 4, 5, and 6 months after surgery. The amounts of analgesic consumed were recorded for the first 24 hours, and for 6 months after surgery. RESULTS: There were no significant differences between the two groups with respect to age, gender, nausea and vomiting, sleep quality, blood pressure, and heart rate. No significant differences were observed between the two groups in pain scores (P = 0.39) and analgesic consumption (P = 0.78). CONCLUSIONS: The results suggest that a single dose of preoperative oral amantadine did not reduce acute or chronic postoperative pain, nor analgesic consumption.

Mandibular Fracture Associated with a Dentigerous Cyst: Report of a Case and Literature Review.

Background and aims . Pathological fractures are rare in the maxillofacial region and account for less than 2% of all fractures in this site. They are defined as fractures that take place when bone has been weakened by an underlying pathologic process. Among all pathoses, cysts (although so common in the maxillofacial region) constitute a very small part. Here we report a case of a dentigerous cyst in a 38-year-old man.The cyst was associated with a mandibular second premolar tooth and resulted in a pathologic fracture. Excision of the lesion was performed and bony union was observed after 6 months. In the literature review, only one case of dentigerous cyst causing pathologic fracture was found. In addition to the report of the present case, pathologic fractures associated with all types of odontogenic cysts (totally just 12 cases) are reviewed in this article to provide a comprehensive and detailed collection.

Efficacy of bilateral mental nerve block with bupivacaine for postoperative pain control in mandibular parasymphysis fractures.

Background and aims. Postoperative pain control is extremely important for both patients and surgeons; in this context, long-acting local anesthesia can play an important role after open reduction of maxillofacial fractures. The purpose of this study was to evaluate the effect of bilateral mental nerve block with bupivacaine on postoperative pain control in mandibular symphyseal fractures. Materials and methods. Fifty patients with pure mandibular symphyseal fractures were studied in two control and study groups. In contrast to the control group, the study group received bilateral mental nerve block with bupivacaine postoperatively. Patients were examined in relation to pain severity and opioid analgesic drug need sequences. Results. The study group needed significantly less opioid than the control group (P<0.01, U=141). The control and study groups were different in first opioid administration time. The control and study groups received first opioid dose in 0-2 and 2-4 hours, respectively. Conclusion. Bilateral mental nerve blocks with bupivacaine can reduce opioid analgesic need and it has a positive effect on postoperative pain control in mandibular symphyseal fractures.

Schwannoma in the midline of hard palate: a case report and review of literature.

Schwannoma is a benign encapsulated slow-growing tumor that originates from Schwann cells of the peripheral nerve sheath. It usually occurs in the head and neck; however, it is rare in the oral cavity. The tongue is the most common site of intraoral schwannomas, followed by the floor of the mouth, palate, gingiva, vestibular mucosa, lips and mental nerve area. We report a rare case of schwannoma in the midline of hard palate with ulcerated surface in a 21-year-old male with a two-month history of a painless swelling on his palate. Clinical, radiographic and histopathological features along with differential diagnosis and treatment are also discussed.

Infratemporal space infection following maxillary third molar extraction in an uncontrolled diabetic patient.

Infratemporal space infection is a rare but serious sequel of odontogenic infection. The diagnosis is difficult due to non spe-cific signs and symptoms. Diabetes mellitus as a definitive risk factor for odontogenic infections needs more consideration during clinical procedures. We report a case of an undiagnosed diabetic patient with isolated infratemporal space infection after tooth extraction with presentation of similar signs and symptoms of temporomandibular joint and muscle problem.

Difficult nasoendotracheal intubation in a patient with severe maxillofacial trauma.

Dental occlusion is key point for proper maxillofacial reconstruction. In this way nasal airway management is extremely important for both oral and maxillofacial surgeons and anesthesiologists. We report a challenging case with severe maxillofacial trauma and nasal obstruction that it managed with a novel anesthetic - surgical procedure.

Interleukin-1 beta, interleukin-6 and TGF-beta in follicular tissue of impacted third molars.

The clinical evaluation and management of impacted third molars remain challenging. The aim of the present study was to investigate possible associations between follicular tissue cytokines and radiographic manifestations of impacted third molar. The population included 72 patients who underwent surgical extraction of impacted third molars. All these patients underwent a preliminary panoramic radiograph. Levels of interleukin-1 beta (IL-1ß), interleukin-6 (IL-6) and transforming growth factor beta (TGF-ß) in tissue extracts were determined using ELISA. There were no significant differences between bony and tissue impaction as regards IL-1ß, IL-6 and TGF-ß levels. Moreover, the same results were obtained as far as the amount of pericoronal space and the presence or absence of a history of pericoronitis are concerned. These results suggest that radiographic findings or a history of pericoronitis are not associated with levels of expression of pro-inflammatory cytokines in patients undergoing surgical removal of impacted third molars. However, further studies are needed to address the possibility of variability during disease progression.

Analysis of the pattern of maxillofacial fractures in north western of Iran: A retrospective study.

BACKGROUND: Maxillofacial fractures can lead to substantial long-term functional, esthetic and psychological complications. AIM: The aim of this study is to evaluate these injuries in a Turkish Iranian population. MATERIALS AND METHODS: A retrospective study of 170 patients with 210 maxillofacial fractures admitted to the emergency department of a central referral emergency hospital in the area over a 5 year period is presented. Patients' data included demographic information, etiology, site and associated injuries and complications. RESULTS: Road traffic accident was the commonest cause (40%) and the age group of 21-30 comprised the biggest group (30%). Mandibular fractures outnumbered midface fractures (150 vs. 60). Ramus (21.5%) and zygoma (26.5%) were the commonest fracture regions respectively in mandible and midface. Male: female ratio was 3.8:1 Almost half of patients (46%) had sustained associated injuries most of which was soft tissue laceration of the face (17.5%). 22 patient (13%) had associated complication and the hemorrhage was the commonest form of that (9%). CONCLUSION: It seems that road traffic accidents continue to be the leading cause of maxillofacial fractures and there is an urgent need to implement enhanced regulations and monitoring on motor vehicular traffic.

Comparison of the influence of two flap designs on periodontal healing after surgical extraction of impacted third molars.

BACKGROUND AND AIMS: Impacted lower third molar is found in 90% of the general population. Impacted lower third molar surgery may result in periodontal complications on the distal surface of the adjacent second molar. The aim of this study was to evaluate the effect of flap design on the periodontal status of the second molar after lower third molar surgery. MATERIALS AND METHODS: Twenty patients, with an age range of 18-26 years, participated in the present study. The inclusion criteria consisted of the presence of bilateral symmetrical impacted third molars on panoramic radiographs. The subjects were randomly divided into two groups. The impactions on the left and right sides were operated by Szmyd and triangular flaps, respectively. Postoperative management and medications were similar for both groups. The subjects were evaluated at two-week, one-month, and six-month postoperative intervals by a surgeon who was blind to the results. Data was analyzed by t-test using SPSS 11 software. RESULTS: There were no significant differences in clinical attachment loss, pocket depth, bone level, plaque index, and free gingival margin between the two flaps (p>0.05). CONCLUSION: The results of the present study did not show any differences in pocket depth, clinical attachment level, bone level and FGM (free gingival margin) between the two flap designs under study.

Evaluating knowledge and attitudes of elementary school teachers on emergency management of traumatic dental injuries: a study in an Iranian urban area.

PURPOSE: The aim of this survey was to evaluate the knowledge and attitudes of Iranian elementary school teachers with regard to emergency management of dental trauma, in a northwestern urban area. MATERIALS AND METHODS: A total of 160 teachers from 40 schools, all selected randomly, were included in the study. A three-part self-administered questionnaire surveying teachers' background, knowledge of the growth patterns of children's dentition, general dental trauma, fractured and avulsed teeth, as well as attitudes regarding dental trauma was used. Chi-square analysis was performed to examine the effect of educational background, gender, length of service and topics they teach on their knowledge and attitudes on the management of dental trauma. RESULTS: A majority of the participants had received tertiary education. Regarding the management of tooth fracture, 52.4% provided appropriate answers. A similar proportion (50.6%) realised that they should replant a permanent avulsed tooth. However, they had little knowledge on the correct procedures; less than a fifth were acquainted with the urgent need for action. Only 38% knew about appropriate washing mediums and about a third were familiar with proper storage media. Health teachers and those with higher educational background (16 years of education) were significantly more knowledgeable regarding the disciplines of avulsion management. Teachers with a high level of experience (third decade) were also more knowledgeable in terms of prevalence of dental trauma accidents. CONCLUSIONS: The current survey indicated a substantial lack of knowledge regarding dental trauma management among elementary school teachers. Educational campaigns to improve their knowledge and awareness seem crucial for this group of adults who are usually the first to respond in cases of dental trauma accidents in schools.

Pathosis associated with radiographically normal follicular tissues in third molar impactions: a clinicopathological study.

BACKGROUND: The follicular tissue around impacted third molars has a potential to develop pathosis. However, it is generally assumed that the absence of abnormal radiolucency indicates the presence of a normal follicle. AIMS: The aim of this study was to investigate abnormalities associated with radiographically normal follicular tissue of third molar impactions. MATERIALS AND METHODS: One hundred eighty-five impacted third molars from 170 patients with no signs of abnormal radiolucency (follicular space < 3 mm) were used for this study. Follicular tissues of the relevant teeth were collected. Specimens were fixed in 10% formalin and stained routinely with hematoxilin and eosin to be independently examined by two pathologists. A diagnosis was registered only when the results from both pathologists were in concordance. Clinical details for each patient were registered in WHO standard forms to undergo chi-square statistical analysis. RESULTS: Fifty-three per cent of the specimens had developed pathosis. The incidence of pathosis was higher in the age group of 20-30 years, in men compared to women and in the mandible compared to the maxilla. CONCLUSION: The findings of this study suggest that radiographic appearance may not be reliable in the diagnosis of pathosis in follicular tissue as a surprisingly high rate of pathosis was found in the absence of any radiographically detectable sign.

Malignant fibrous histiocytoma of the mandible in the context of a traumatic Marjolin's ulcer.

We present a rare manifestation of a chronic mandibular wound with a traumatic diathesis. A 38-year-old male patient sought medical consultation because of painless swelling in the mandibular symphysis and mild paresthesia of the lower lip. He mentioned a history of physical trauma to the mandibular symphysis 12 months ago. The radiographic evaluation and CT scan showed gross destruction of bone leading to a well-defined radiolucent lesion without any sclerosing margins. The histological examination revealed numerous spindle-shaped fibroblasts arranged in a fascicular pattern and scattered multinucleated and mononuclear cells with bizarre nuclei throughout the lesion. Moderate nuclear pleomorphism was evident with few mitotic cells. The lesion was diagnosed as a malignant fibrous histiocytoma of storiform-pleomorphic type based on the previous descriptions. After surgical removal of the lesion and the adjacent tissues and reconstruction, the patient was referred to a radiotherapist for continuation of treatment. Despite this therapy, the lesion recurred after a year, and prior to the second operation, the patient died as a result of brain involvement.