Evaluation of the angulation of the nasal septum deviation as an anatomical variation for increased frequency of antral pseudocyst: a cone-beam computed tomography study.

BACKGROUND: The aim of the study was to determine whether degree of the nasal septum deviation (NSD) can affect the frequency of antral pseudocyst (AP) formation by cone-beam computed tomography (CBCT). MATERIALS AND METHODS: This retrospective study was included 466 CBCT images. The NSD were categorised into four groups according to the degree: control group (no NSD, 0°-2°), group A (2°-9°), group B (9°-15°), and group C (≥ 15°). The predictor variables were demographic factors (patient's age and gender) and anatomic factors (different degrees of nasal septum angulation). The outcome variable was presence of AP. RESULTS: Of the 466 cases, 242 (51.9%) had no NSD, 66 (14.2%) had an angle of 2°-9°, 111 (23.8%) had an angle of 9°-15°, and 47 (10.1%) had an angle of over 15°. The prevalence of AP was 2.04 (95% confidence interval [CI] 1.37 to 3.03; p = 0.001) times higher in the presence of NSD. Significant increases in presence of AP occurred with NSD in group A (2.37 times higher; p = 0.003) and group B (2.07 times higher; p = 0.003) compared to control by univariate analysis. CONCLUSIONS: Although there is no sufficient evidence to suggest that NSD is a definitive aetiological factor for AP development, our findings indicated that NSD increased the risk of AP formation.

Nonuniformity in Periodontal Ligament: Mechanics and Matrix Composition.

The periodontal ligament (PDL) plays a critical role in providing immediate response to abrupt high loads during mastication while also facilitating slow remodeling of the alveolar bone. The PDL exceptional functionality is permitted by the unique nonuniform structure of the tissue. Two distinct areas that are critical to PDL function were previously identified: the furcation and the dense collar. Despite their hypothesized functions in tooth movement and maintenance, these 2 regions have not yet been compared within the context of their native environment. Therefore, the objective of this study is to elucidate the extracellular matrix (ECM) structure, composition, and biomechanical function of the furcation and the collar regions while maintaining the 3-dimensional (3D) structure in the murine PDL. We identify significant difference between the collar and furcation regions in both structure and mechanical properties. Specifically, we observed unique longitudinal structures in the dense collar that correlate with type VI collagen and LOX, both of which are associated with increased type I collagen density and tissue stiffness and are therefore proposed to function as scaffolds for tooth stabilization. We also found that the collar region is stiffer than the furcation region and therefore suggest that the dense collar acts as a suspense structure of the tooth within the bone during physiological loading. The furcation region of the PDL contained more proteins associated with reduced stiffness and higher tissue remodeling, as well as a dual mechanical behavior, suggesting a critical function in loads transfer and remodeling of the alveolar bone. In summary, this work unravels the nonuniform nature of the PDL within the 3D structural context and establishes understanding of regional PDL function, which opens new avenues for future studies of remodeling, regeneration, and disease.

Effects of alloplastic graft material combined with a topical ozone application on calvarial bone defects in rats.

BACKGROUND: This study presents the evaluation of the damage in the bone tissue resulting from a calvarial defect in rats and the efficiency of exposure to an ozone application with an alloplastic bone graft on the calvarial bone damage. MATERIALS AND METHODS: Wistar male rats (n = 56) were divided into four groups: a control group (n = 14), defect and ozone group (n = 14), defect and graft group (n = 14), and defect, graft, and ozone group (n = 14). Under anaesthesia, a circular full-thickness bone defect was created in all groups, and the experimental groups were further divided into two sub-groups, with 7 rats in each group sacrificed at the end of the 4th and 8th weeks. Bone samples were dissected, fixed in 10% formalin solution, and decalcified with 5% ethylene-diamine-tetraacetic acid (EDTA). After the routine follow-up on tissues, immunostaining of osteopontin and osteonectin antibodies was applied to sections and observed under a light microscope. RESULTS: The control group exhibited osteopontin and osteonectin expression in fibroblasts and inflammatory cells at the end of the 4th week with an acceleration at the 8th week. Ozone administration elucidated new trabecular bone formation by increasing osteoblastic activity. Lastly, our observations underscore that a combination of allograft and ozone application increased the osteoblast, osteocyte, and bone matrix development at the 4th and 8th weeks. CONCLUSIONS: Exposure to an ozone application with an alloplastic bone graft on calvarial bone damage may induce osteoblastic activity, matrix development, mature bone cell formation, and new bone formation in rats.

Evaluation of pneumatic cavities surrounding temporomandibular joint by cone beam computed tomography.

OBJECTIVE: The purpose of this study was to detect the prevalence and characteristics of pneumatization in the roof of the glenoid fossa (PRGF) and articular eminence (PAT) by using cone beam computed tomography (CBCT) images. MATERIAL AND METHOD: CBCT images of 378 patients (756 TMJ) were analyzed to determine the PRGF and PAT. Twenty-eight patients were excluded due to some reasons such as trauma, degeneration, previous surgical operation of temporomandibular joint (TMJ). Pneumatization was detected in 297 of 350 patients, but not pneumatization in 53 patients. Age, gender, laterality (unilateral, bilateral) and lacunarity (unilacunar, multilacunar) were recorded. Unilateral types were also noted as right and left localization. Chi-square test was used to evaluate relationship between pneumatization and gender, lacunarity and laterality. RESULTS: PRGF and/or PAT were diagnosed in 491 (70%) TMJ components whom 178 (51%) were male and 172 (49%) were female with mean age of 40.38±18.34 years. In total, 103 (35%) of the patients had unilateral and 194 (65%) patients had bilateral pneumatization. CONCLUSION: CBCT provides reliable and precise images to detect pneumatization surrounding TMJ structure in comparison to 2D images. Evaluation of TMJ components accurately before surgical intervention is crucial to prevent complication or increase the success of therapy.

Effects of formaldehyde on vascular endothelial growth factor, matrix metallopeptidase 2 and osteonectin levels in periodontal membrane and alveolar bone in rats.

BACKGROUND: The objective of this study was to investigate whether long term formaldehyde inhalation may affect periodontal membrane and alveolar bone loss leading to periodontitis. The negative effects of formaldehyde were described using vascular endothelial growth factor (VEGF), matrix metallopeptidase 2 (MMP-2) and osteonectin antibodies involved in the extracellular matrix and angiogenetic development. MATERIALS AND METHODS: Thirty adult Wistar albino rats were used in this study. Rats were divided into two groups: a control group (n = 15) and formaldehyde administered group (n = 15). Formaldehyde group was exposed to inhalation of 10 ppm formaldehyde 8 hours a day, 5 days a week for 5 weeks. Maxillary bone regions were dissected under anaesthesia. After fixation in 10% formaldehyde solution, tissues were passed through graded ethanol series to obtain paraffin blocks. Five-micrometre histological sections were cut with RM2265 rotary microtome stained with Masson trichrome and VEGF, MMP-2 and osteonectin antibodies for examination under Olympus BH-2 light microscopy. RESULTS: The present study revealed that congestion in blood vessels, degeneration of collagen fibres and alveolar matrix around alveolar bone were observed to be more significant in formaldehyde group than the control group (p ≤ 0.001). Interestingly, VEGF expression in the formaldehyde group was the most significant finding between the two groups (p < 0.001). When compared inflammation, MMP-2 and osteonectin expressions were significant (p < 0.01) in the formaldehyde group. CONCLUSIONS: It was suggested that formaldehyde toxicity decreased the expression of MMP-2 and in osteoblasts as well as affecting the retention of MMP levels in tooth cavity, which is very low in collagen fibres. But, vice versa for the expression of VEGF in dilated vascular endothelial cells and osteocytes in alveolar bone. As a conclusion, formaldehyde disrupts the periodontal membrane and may cause collagen fibres degeneration by affecting the alveolar bone matrix.

Prevalence of traumatic dental injuries and associated factors among 8 to 12-years-old schoolchildren in Diyarbakir, Turkey.

BACKGROUND AND OBJECTIVES: This study aimed to assess the prevalence of traumatic injuries of the permanent incisors in public primary schoolchildren from 8 to 12 years old in South-Eastern Anatolia, Turkey. Additionally, the relationship between traumatic dental injuries, parents' education level, family income, size of incisal overjet and the presence of anterior open bite were examined. MATERIALS AND METHODS: Data were collected through oral examinations and structured interviews, and included socio-economic indicators. A total of 2907 children of both genders (1498 boys, 1409 girls) were included in the study. The response rate was 97%. RESULTS: The prevalence of dental injuries was 4.6% (n = 135). The highest frequency of trauma in permanent teeth was observed at the age of 12 (8%). Boys experienced more dental injuries than girls, 5.9% and 3.3% (p = 0.001), respectively. The most commonly reported cause of injuries to the permanent incisors was falls (71.8%), followed by collision with objects or people (17.8%). Maxillary central incisors were the most affected by dental injuries (154, 84.6%). The most common crown fracture was in enamel only (67.58%) followed by crown fracture of enamel and dentin (22.52%). CONCLUSION: Socio-economic indicators and parents' level of education were not statistically significantly associated with the occurrence of traumatic dental injuries. Factors associated with increased risk of dental injuries in permanent teeth were age, gender, having an incisal overjet greater than 5mm and anterior open bite.