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Guided bone regeneration (GBR) procedures using graft materials have been used for reconstruction of osseous defects. The aim of the present in vivo micro-computed tomographic (µCT) and histologic study was to assess in real time the bone regeneration at GBR sites in standardized experimental calvarial defects (diameter 3.3 mm) using β-tricalcium phosphate (β-TCP) with and without collagen membrane (CM). A single full-thickness calvarial defect was created on the left parietal bone in young female Wistar albino rats (n = 30) weighing approximately 300 g and aged about 6 weeks. The animals were randomly divided into three groups for treatment, based on calvarial defect filling material: (1) control group (n = 10); (2) β-TCP + CM group (n = 10); (3) β-TCP group (n = 10). Real-time in vivo µCT analyses were performed immediately after surgery and at 2, 4, 6 and 10 weeks to determine the volume and mineral density of the newly formed bone (BVNFB, MDNFB) and remaining β-TCP particles (VRBP, MDRBP). The animals were killed at 10 weeks and calvarial specimens were evaluated histologically. In the control group, MDNFB increased significantly at 6 weeks (0.32 ± 0.002 g/mm(3), P < 0.01) compared to that at baseline. In β-TCP + CM group, BVNFB (1.10 ± 0.12 mm(3), P < 0.01) and MDNFB (0.13 ± 0.02 g/mm(3), P < 0.01) significantly increased at the 4th week than baseline. In the β-TCP group, BVNFB (1.13 ± 0.12 mm(3), P < 0.01) and MDNFB (0.14 ± 0.01 g/mm(3), P < 0.01) significantly increased at 6 weeks compared to that at baseline. Significant reduction in VRBP was neither seen in the β-TCP + CM group nor in the β-TCP group. While in the β-TCP + CM group MDRBP was reduced significantly at 6 weeks (0.44 ± 0.9 g/mm(3), P < 0.01) from baseline (0.98 ± 0.03 g/mm(3)), similar significant reduction in MDRBP from baseline (0.92 ± 0.07 g/mm(3)) was seen only at 10 weeks (0.45 ± 0.06 g/mm(3), P < 0.05) in the β-TCP group. Histologic findings at 10 weeks revealed greater amount of NFB with osteocytes in the matrix, in the β-TCP + CM group than in the β-TCP group. Biomechanical assessment of NFB for hardness (H) and elastic modulus (E) revealed significantly higher values for the β-TCP + CM group (H = 612.6 ± 4.28 Mpa; E = 13.57 ± 0.07 Gpa) when compared to those of the control (H = 192.1 ± 4.93 Mpa; E = 6.76 ± 0.04 Gpa) and the β-TCP groups (H = 241.9 ± 6.29 Mpa; E = 4.34 ± 0.06 Gpa). In conclusion, based on real-time assessment, NFB is formed in calvarial defects as early as 4 weeks following GBR with β-TCP + CM as compared to 6 weeks when β-TCP alone was used.

Based on the results of this study, perioperative oral antibiotics in combination with antibacterial mouthwashes are effective in preventing ORN following dental extractions in irradiated patients.

The aim of the present real time in vivo micro-computed tomography (µCT) and histologic experiment was to assess the efficacy of guided bone regeneration (GBR) around standardized calvarial critical size defects (CSD) using bone marrow-derived mesenchymal stem cells (BMSCs), and collagen membrane (CM) with and without tricalcium phosphate (TCP) graft material. In the calvaria of nine female Sprague-Dawley rats, full-thickness CSD (diameter 4.6 mm) were created under general anesthesia. Treatment-wise, rats were divided into three groups. In group 1, CSD was covered with a resorbable CM; in group 2, BMSCs were filled in CSD and covered with CM; and in group 3, TCP soaked in BMSCs was placed in CSD and covered with CM. All defects were closed using resorbable sutures. Bone volume and bone mineral density of newly formed bone (NFB) and remaining TCP particles and rate of new bone formation was determined at baseline, 2, 4, 6, and 10 weeks using in vivo µCT. At the 10th week, the rats were killed and calvarial segments were assessed histologically. The results showed that the hardness of NFB was similar to that of the native bone in groups 1 and 2 as compared to the NFB in group 3. Likewise, values for the modulus of elasticity were also significantly higher in group 3 compared to groups 1 and 2. This suggests that TCP when used in combination with BMSCs and without CM was unable to form bone of significant strength that could possibly provide mechanical “lock” between the natural bone and NFB. The use of BMSCs as adjuncts to conventional GBR initiated new bone formation as early as 2 weeks of treatment compared to when GBR is attempted without adjunct BMSC therapy.

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Background:The biological effects of hemostatic agends on the physiological healing process need to be tested. The aim of this study was to assess the effects of oxidized cellulose (surgicel) and bone wax on bone healing in goats’ feet.Materials and Methods:Three congruent circular bone defects were created on the lateral aspects of the right and left metacarpal bones of ten goats. One defect was left unfilled and acted as a control; the remaining two defects were filled with bone wax and surgicel respectively. The 10 animals were divided into two groups of 5 animals each, to be sacrificed at the 3rd and 5th week postoperatively. Histological analysis assessing quality of bone formed and micro-computed tomography (MCT) measuring the quantities of bone volume (BV) and bone density (BD) were performed. The results of MCT analysis pertaining to BV and BD were statistically analyzed using two-way analysis of variance (ANOVA) and posthoc least significant difference tests.Results:Histological analysis at 3 weeks showed granulation tissue with new bone formation in the control defects, active bone formation only at the borders for surgicel filled defects and fibrous encapsulation with foreign body reaction in the bone wax filled defects. At 5 weeks, the control and surgicel filled defects showed greater bone formation; however the control defects had the greatest amount of new bone. Bone wax filled defects showed very little bone formation. The two-way ANOVA for MCT results showed significant differences for BV and BD between the different hemostatic agents during the two examination periods.Conclusion:Surgicel has superiority over bone wax in terms of osseous healing. Bone wax significantly hinders osteogenesis and induces inflammation.

Introduction:Ventilator-associated pneumonia is a major morbid outcome among intensive care unit (ICU) patients. Providing oral care for intubated patients is an important task by the ICU nursing staff in reducing the mortality and morbidity. The objectives of this study were to evaluate the attitudes and knowledge of ICU nurses regarding oral care delivery to critically ill patients in Saudi Arabian ICUs. The findings were further correlated to the presence of healthcare quality accreditation of the institution.Materials and Methods:The nurses’ knowledge, attitudes, and healthcare quality accreditation status of the hospital were recorded. Two hundred fifteen nurses conveniently selected from 10 random hospitals were included in this study from Riyadh city, Saudi Arabia. This is a cross-sectional study in the form of a questionnaire.Results:When comparing the knowledge of the participants to their level of education, there was no statistically significant difference between the two groups of nurses. The majority of the nurses agreed that the oral cavity is difficult to clean and that oral care delivery is a high priority for mechanically ventilated patients. Furthermore, there was no statistically significant difference in the attitudes between nurses working in accredited and nonaccredited hospitals.Conclusion:The presence of healthcare quality accreditation did not reflect any significance in attitudes or knowledge of the ICU nurses in regard to mechanically ventilated patients. Factors affecting oral care delivery should be evaluated on the personal and institutional level to achieve better understanding of them.

Lateral periodontal cyst (LPC) is an uncommon developmental odontogenic cyst arising on the lateral surface of tooth roots. Commonly reported in mandibular canine-premolar or maxillary anterior regions, it presents as a well-circumscribed or tear drop-shaped radiolucency with a sclerotic border. Associated teeth are asymptomatic and vital, and roots may be displaced without resorption. Histopathologically, cystic lining resembles reduced enamel epithelium along with glycogen-rich clear cells and epithelial plaques. Unilateral variant of LPC has low recurrence and is managed by enucleation. A 43-year-old male patient reported with asymptomatic swelling in the left mandibular canine and first premolar region. Both teeth were vital, and radiographs revealed well-circumscribed radiolucency between the roots. Following consent, surgical enucleation and guided bone regeneration (GBR) with xenograft and resorbable collagen membrane were done under local anesthesia. The immediate postoperative period was uneventful, and complete bone fill of cystic cavity and healing of periodontal tissues was observed after a one-year follow-up. Histopathologic examination confirmed the diagnosis. LPC should be a differential diagnosis in cystic lesions lateral to the surface of a tooth and without any associated inflammation. Based on this case report, unicystic LPC can be successfully managed through surgical enucleation with GBR for better periodontal healing.