ABSTRACT
BACKGROUND: The aim of this study was to evaluate the effects of bone resorption inhibitors, doxycycline (DOX) and erythromycin (EM), on osseous wound healing in rat alveolar socket. MATERIALS AND METHODS: In this randomized controlled trial, 45 8-10-week-old male Wistar rats had their maxillary right molar extracted. They were divided into three groups of 15. In Group 1 normal saline, Group 2 DOX, and Group 3 EM were administered at the doses of 5 ml/kg/day, 5 mg/kg/day, and 2 mg/kg/day, respectively, for 7 consecutive days. The rats were sacrificed 7, 14, and 21 days after surgery. Real-time polymerase chain reaction was employed to evaluate the mRNA expression of receptor activator of nuclear factor κB ligand (RANKL) and osteoprotegerin (OPG) and immunohistochemical staining for tartrate-resistant acid phosphatase (TRAP) to determine osteoclasts. The data were analyzed by one-way analysis of variance followed by Tukey's post hoc test using SPSS version 20. Significant level was set at 0.05. RESULTS: The results showed that when drug-treated groups compared to control groups, RANKL gene expression significantly decreased, TRAP+ cells decreased on day 7. The RANKL/OPG ratios in the first two weeks in the test groups were significantly lower than the control group. There was no significant difference in the studied indices between DOX and EM groups. CONCLUSION: Following administration of DOX and EM, the number of osteoclasts and RANKL/OPG ratio decreased suggesting their anti-osteoclastogenesis activity. These two drugs have no advantage over each other in increasing the bone formation.
ABSTRACT
BACKGROUND: The aim of the present study was to evaluate whether subantimicrobial doses of doxycycline (DOX) and erythromycin (EM) used for the treatment of peri-implant osteolysis due to their anti-osteoclastogenesis can interfere with the osseous wound healing process in rat alveolar socket. MATERIALS AND METHODS: Forty-five male Wistar rats had their first maxillary right molar extracted and were divided into three groups. DOX and EM at the doses of 5 mg/kg/day orally (p.o.) and 2 mg/kg/day intraperitoneally (i.p.) were administered respectively to two separate groups for 7 days after operation. In the control group the animals received normal saline (5 ml/kg). Five rats were sacrificed at 7, 14 and 21 days post-extraction in each study group. A histomorphometric analysis was used to evaluate new bone formation inside the alveolar socket. Significant level was set at 0.05. RESULTS: The findings showed that the percentage of new bone formation (NBF) enhanced significantly on days 7 and 14. There was no significant difference in the NBF between DOX and EM groups. CONCLUSION: Short-term treatment with both DOX and EM enhanced new bone formation without any advances in favor of each drug.
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OBJECTIVE: Recent advances in the field of alternative medicine introduced various herbal products for the treatment of periodontitis. The purpose of this study was to evaluate the effects of combined extracts from Quercus brantii and Coriandrum sativum on periodontal indices in adult periodontitis patients. METHODS: In this randomized, double-blinded clinical trial, performed in Isfahan Dental School in 2012, a new herbal medicament containing combined extracts from Q. brantii and C. sativum was formulated in the gel form for subgingival application. Following scaling and root planing (SRP), both herbal and placebo gels were delivered at the experimental and control sites, respectively. Periodontal pocket depth, clinical attachment level, papilla bleeding index, and plaque index were measured at baseline, 1 month and 3 months later. Both intra-and inter-groups changes were registered. The obtained data were analyzed by SPSS software, using repeated measure analysis of variance, paired t-test, Mann-Whitney, Friedman, and Wilcoxon tests. Differences with P < 0.05 were considered to be significant. FINDINGS: Both groups indicated statistically significant improvements in the periodontal indices (P < 0.05), but there were no significant differences between two study groups with this regard. CONCLUSION: The herbal gel does not have considerable advantages over SRP alone as an adjunct in periodontal treatment.
ABSTRACT
BACKGROUND: Tissue engineering principles can be exploited to enhance alveolar and peri-implant bone reconstruction by applying such biological factors as platelet-derived growth factors. The objective of the present study is to investigate the effect of autologous plasma-rich in growth factors (on the healing of peri-implant bone in canine mandible). MATERIALS AND METHODS: In this prospective experimental animal study, two healthy canines of the Iranian mix breed were selected. Three months after removing their premolar teeth on both sides of the mandible, 12 implants of the Osteo Implant Corporationsystem, 5 mm in diameter and 10 mm in length, were selected to be implanted. Plasma rich in growth factors (PRGF) were applied on six implants while the other six were used as plain implants without the plasma. The implants were installed in osteotomy sites on both sides of the mandible to be removed after 4 weeks with the surrounding bones using a trephine bur. Mesio-distal sections and implant blocks, 50 µ in diameter containing the peri-implant bone, were prepared By basic fuchin toluidine-bluefor histological and histomorphometric evaluation by optical microscope. The data were analyzed using Mann-Whitney Test (P<0.05). RESULTS: The bone trabeculae and the type of bone generation in PRGF and control groups had no statistically significant differences (P=0.261, P=0.2) although the parameters showed higher measured values in the PRGF group. However, compared to the control, application of PRGF had significantly increased bone-to-implant contact (P=0.028) CONCLUSION: Based on the results, it may be concluded that application of PRGF on the surface of implant may enhance bone-to-implant contact.
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BACKGROUND: It has been stated that the bone allografts from different tissue banks may lead to various amount of bone induction, so the aim of this study was to evaluate bone regeneration of three demineralized allografts both histologically and histomorphometrically in rabbits calvaria bone defects. MATERIALS AND METHODS: In this double-blind randomized experimental animal study, 32 critical size defects (11-mm diameter) in the calvaria of 16 male New Zealand white rabbits were randomly filled with three demineralized freeze-dried bone allografts (DBM, CENOBONE, DEMBONE), while the nongrafted defect was regarded as control group. After 6 and 12 weeks of healing, the experimental animals were euthanized for specimen preparation. After histological evaluation, histomorphometric analysis was performed to quantify new bone formation and remained graft particles. The data were analyzed by one-way ANOVA with Tukey's ad-hoc test and t-test. (P < 0.05 was considered to be statistically significant). RESULTS: Mean percentage of bone formation increased between two healing time, but it was not statistically significant in all groups except DBM which the bone formation significantly decreased (P = 0.04). There were not statistically significant differences between three allografts in remained particles and bone formation in both healing times and they could not induce significantly more bone formation than control group. CONCLUSION: Both test and control groups resulted in successful new bone formation. No difference was noted in bone formation and remained particles between three commercial bone allografts. Further studies in this issue may be needed.
ABSTRACT
BACKGROUND: The purpose of this study was to perform a histological, histomorphometrical, and immunohistochemical evaluation of the effect of Enamel matrix derivative (EMD) on bone formation around titanium dental implant. MATERIALS AND METHODS: In this animal study, 12 implants (10 × 3.8 mm) were inserted in the tibia bone of three dogs of Iranian breed. Two implants were placed in each tibia with EMD only on the left side. The dogs were sacrificed 2, 4, and 6 weeks after implantation. Following decalcification of the implants' surrounding tissue and preparation of 4 µm thick sections, they were stained with hematoxylin and eosin (H and E) and immunohistochemical (IHC) stain for osteopontin (OPN) marker. Histomorphometric evaluation was performed via measurement of the percentage of the woven, lamellar, and total generated bone. Light microscopy osteoblastic intensity of OPN in osteoblasts and bone matrix was also evaluated Data were analyzed by Wilcoxon signed Ranks, and Mc Nemar tests. RESULTS: In both control and EMD-applied groups, bone formation was recognized around the implants at the 4(th) week postimplantation. The percentage of total generated bone in the test group was higher than the control group, although being not statistically significant (P value = 0.917). Osteoclasts exhibited significantly higher proliferation activity compared the control group when stimulated by EMD (P value = 0.027). On average, the staining intensity in osteoblasts and extracellular matrix of bone, in EMD-applied subjects was higher than those of the controls (P value = 0.167 and P value = 0.414, respectively). CONCLUSION: EMD enhanced bone formation around dental implants, but this increase was not significant.
