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BACKGROUND: This study was performed to determine the therapeutic effects of diosgenin (DG) which is a steroidal saponin, administered at different doses on alveolar bone loss (ABL) in rats with experimental periodontitis using immunohistochemical and cone-beam computed tomography (CBCT). METHODS: Thirty-two male Wistar rats divided into four equal groups: control (non-ligated), periodontitis (P), DG-48, and DG-96. Sutures were placed at the gingival margin of the lower first molars to induce experimental periodontitis. Then, 48 and 96 mg/kg of DG was administered to the study groups by oral gavage for 29 days. At day 30, the animals were sacrificed and ABL was determined via CBCT. The expression patterns of osteocalcin (OCN), alkaline phosphatase (ALP), type I collagen (Col-1), B cell lymphoma 2 (Bcl 2), Bcl 2-associated X protein (Bax), bone morphogenetic protein 2 (BMP-2), and receptor activator of NF κB ligand (RANKL) were examined immunohistochemically. RESULTS: Histopathologic examination showed all features of the advanced lesion in the P group. DG use decreased all these pathologic changes. It was observed that periodontitis pathology decreased as the dose increased. DG treatment increased the ALP, OCN, Bcl 2, Col-1, and BMP-2 levels in a dose-dependent manner, compared with the P group (p < 0.05). DG decreased the expression of RANKL and Bax in a dose-dependent manner (p < 0.05). ABL was significantly lower in the DG-48 and DG-96 groups than in the P group (p < 0.05). CONCLUSION: Collectively, our findings suggest that DG administration protects rats from periodontal tissue damage with a dose-dependent manner, provides an increase in markers of bone formation, decreases in Bax/Bcl-2 ratio and osteoclast activation.
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Fosfatasa Alcalina , Pérdida de Hueso Alveolar , Proteína Morfogenética Ósea 2 , Osteocalcina , Periodontitis , Ligando RANK , Ratas Wistar , Animales , Masculino , Periodontitis/tratamiento farmacológico , Periodontitis/patología , Ratas , Pérdida de Hueso Alveolar/prevención & control , Pérdida de Hueso Alveolar/diagnóstico por imagen , Pérdida de Hueso Alveolar/patología , Proteína Morfogenética Ósea 2/metabolismo , Ligando RANK/metabolismo , Ligando RANK/análisis , Tomografía Computarizada de Haz Cónico , Proteína X Asociada a bcl-2/metabolismo , Proteína X Asociada a bcl-2/análisis , Colágeno Tipo I/análisis , Colágeno Tipo I/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/análisis , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Inmunohistoquímica , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a DrogaRESUMEN
This experimental study aimed to evaluate the effects of injectable platelet-rich fibrin (i-PRF) on mucosal healing and the release of growth factors in rats. 40 rats were used; i-PRF was administered in the right buccal area while saline was injected in the left. Cytokeratin, FGF, PDGF, TGF, and VEGF expressions were determined with immunohistochemistry. Gene expressions of EGF, TGF-ß, and VEGF were analysed. Epithelialization started on the 3rd day, and connective tissue maturation was more prominent in the i-PRF-applied group. Also, the releases of VEGF, EGF, TGF-ß, PDGF, and FGF were higher in the i-PRF group during the 14 days. Gene expression analysis showed that changes in TGF-ß at 14 days after i-PRF injection and VEGF after 21 days were statistically significant. The results of this study suggested that autologous i-PRF application enhanced the healing of oral mucosal wounds by increasing the release of growth factors for 21 days.
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Fibrina Rica en Plaquetas , Ratas , Animales , Fibrina Rica en Plaquetas/metabolismo , Factor de Crecimiento Epidérmico , Factor A de Crecimiento Endotelial Vascular/genética , Factor A de Crecimiento Endotelial Vascular/metabolismo , Cicatrización de Heridas , Boca/metabolismo , Factor de Crecimiento Transformador beta/metabolismo , Factores Inmunológicos/metabolismoRESUMEN
OBJECTIVES: This single-center, randomized clinical trial evaluated and compared retainer bonding among different methods and adhesives in terms of periodontal status and failure rates. MATERIALS AND METHODS: A total of 100 patients from the orthodontic department of Pamukkale University were randomly assigned to the following 4 groups: group 1, direct bonding (DB) with two-step adhesive; group 2, DB with one-step adhesive; group 3, indirect bonding (IDB) with two-step adhesive; and group 4, IDB with one-step adhesive. Eligibility criteria included good finishing results and oral hygiene, no periodontal or systemic problems, and no missing anterior teeth or restorations. Randomization was carried out using computer-generated random numbers with allocation concealment by opaque, sealed envelopes. The main outcomes were plaque index (PI), gingival index (GI), and calculus index (CI) recorded at bonding, 6 months (T1), and 12 months (T2) after bonding. A secondary outcome was failure rate. The periodontal outcome assessor was blinded. Data were analyzed using the Mann-Whitney U-test, Kruskal-Wallis test, and chi-square test. RESULTS: PI and GI increased with time in all study groups, but there were no significant differences among groups at any time point. A small amount of calculus was observed in all study groups, with the increase in CI for group 3 significantly greater at the T2-T1 time interval (P < .05). There were no significant differences between groups for 12-month failure rates. CONCLUSIONS: The one-step retainer adhesive was similar in terms of periodontal status and failure rate. Therefore, a one-step adhesive can be used during bonding, regardless of technique.
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Cálculos , Recubrimiento Dental Adhesivo , Humanos , Recubrimiento Dental Adhesivo/métodos , Cementos Dentales , Higiene BucalRESUMEN
We investigated the therapeutic potential of taxifolin for treatment of alveolar bone loss (ABL) in experimental periodontitis in diabetic rats. Diabetes mellitus (DM) was induced by streptozotocin. Rats were divided into six groups: untreated control; DM only (D) group; ligature only (P) group; DM + ligature (DP) group; DM + ligature + 5 mg/kg/day taxifolin (Taxi-5) group; DM + ligature + 10 mg/kg/day taxifolin (Taxi-10) group. Experimental periodontitis was induced by ligation of the first molar and allowed to progress for 30 days before performing cone-beam computed tomographic (CBCT), histomorphometric and immunohistochemical analyses of periodontal tissue destruction. ABL was assessed using CBCT. ABL was greatest in the P and DP groups. Decreased ABL was observed in the Taxi-5 and Taxi-10 groups. Bone morphogenic protein (BMP-2), osteocalcin (OCN), receptor activator of nuclear factor kappa-Β ligand (RANKL), alkaline phosphatase (ALP), type I collagen, B cell lymphoma-associated X (Bax), and B-cell lymphoma 2 (Bcl-2) levels were investigated using immunohistochemistry. The Taxi-5 and Taxi-10 groups exhibited decreased RANKL expression, but increased BMP-2, ALP, type I collagen and OCN levels compared to the P and DP groups. Bax activity was increased in the D, P and DP groups. Taxi-5 and Taxi-10 groups exhibited increased Bcl-2 activity. Our findings suggest that taxifolin can reduce apoptosis and improve alveolar bone formation in diabetic rats with periodontitis.
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Diabetes Mellitus Experimental , Periodontitis , Animales , Apoptosis , Diabetes Mellitus Experimental/tratamiento farmacológico , Diabetes Mellitus Experimental/metabolismo , Osteogénesis , Periodontitis/metabolismo , Quercetina/análogos & derivados , RatasRESUMEN
INTRODUCTION: Bone regeneration depends on vascularization in the pertaining site. This study aims to investigate autogenous bone grafts mixed with recombinant human vascular endothelial growth factor (rhVEGF) effect on bone regeneration in rat mandibular bone defect. MATERIAL METHODS: Using 32 Wistar Albino rats, our experimental study consists of 4 groups: Group1 (control group), the defect was empty; Group 2, autogenous bone graft only; Group 3, gelatin sponge plus rhVEGF applications; Group 4, autogenous bone graft plus rhVEGF applications. The rats were sacrificed on the 28th day after the operation. New bone regeneration was analyzed histologically and immunohistochemically. RESULTS: Our histological analyses revealed that new bone regeneration in Group 3 was enhanced in comparison to Group 1 and Group 2. However, autogenous bone grafts combined with rhVEGF provided the best outcome in conjunction with the increased remodeling of the new bone. CONCLUSIONS: In the light of our results, it can be concluded that autogenous bone grafts in combination with rhVEGF can, potentially, enhance neovascularization and bone regeneration.
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Regeneración Ósea , Factor A de Crecimiento Endotelial Vascular , Animales , Trasplante Óseo , Humanos , Mandíbula/cirugía , Ratas , Ratas WistarRESUMEN
The aim of this study was to evaluate the effect of autogenous tooth bone graft (ATBG) combined with platelet-rich fibrin (PRF) on bone healing in rabbit peri-implant osseous defects. Eighteen New Zealand rabbits were divided into 3 groups. Bone defects were prepared in each rabbit, and then an implant cavity was created in the defects. Dental implants were placed, and the peri-implant bone defects were treated with the following 3 methods: no graft material was applied in the control group, bone defects were treated with ATBG in the ATBG group, and bone defects were treated with ATBG combined with PRF in the ATBG+PRF group. After 28 days, the rabbits were sacrificed, and the dental implants with surrounding bone were removed. New bone formation and the percentage of bone-to-implant contact (BIC) were determined with histomorphometric evaluations. New bone formation was significantly higher in the ATBG+PRF group than the control and ATBG groups (P < .05). In addition, BIC was significantly higher in the ATBG+PRF group than in the control and ATBG groups (P < .05). The combination of ATBG with PRF contributed to bone healing in rabbits with peri-implant bone defects.
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Implantes Dentales , Fibrina Rica en Plaquetas , Animales , Regeneración Ósea , Trasplante Óseo , Fibrina , ConejosRESUMEN
OBJECTIVE: This study aimed to evaluate the effect of taxifolin, a powerful antioxidant, on the progression of periodontitis by immunohistochemical and cone-beam computed tomography (CBCT) examination. DESIGN: This study was performed with 32 rats in four experimental groups: a non-ligated group (Control, n = 8), periodontitis group (Perio, n = 8), periodontitis with 1 mg/kg/day taxifolin group (Taxi-1, n = 8), and periodontitis with 10 mg/kg/day taxifolin group (Taxi-10, n = 8). A ligature-induced experimental periodontitis design was used. All rats were sacrificed at 30 days. Alveolar bone loss was determined by CBCT. Hematoxylin-eosin stained slides were examined. The expression levels of bone morphogenetic protein 2 (BMP-2), osteocalcin (OCN), alkaline phosphatase (ALP), collagen type I (Col 1), Bcl-2, Bax, and receptor activator of NF-κB ligand (RANKL) were determined immunohistochemically. RESULTS: Both doses of taxifolin showed a decrease in alveolar bone loss. The inflammatory reaction was higher in the Perio group and lower in the taxifolin groups. BMP-2, OCN, ALP, and Col 1 expression were dose-dependently elevated in the taxifolin groups. RANKL immunoexpression decreased with both doses of taxifolin. Bcl-2 expression increased and Bax expression decreased in the taxifolin groups. CONCLUSION: Taxifolin successfully reduced apoptosis and improved bone formation in alveolar bone in this experimental periodontitis model.
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Pérdida de Hueso Alveolar , Periodontitis , Quercetina/análogos & derivados , Pérdida de Hueso Alveolar/diagnóstico por imagen , Pérdida de Hueso Alveolar/tratamiento farmacológico , Animales , Apoptosis , Osteocalcina , Periodontitis/tratamiento farmacológico , Quercetina/farmacología , Ligando RANK/metabolismo , RatasRESUMEN
Tideglusib is a glycogen synthase kinase 3 (GSK-3) inhibitor which has shown the effects of bone regeneration, used for the treatment of Alzheimer disease. The aim of the study was to determine the effects of Tideglusib in the apoptosis and the bone regeneration in rats with calvarial defects. Twenty male Wistar rats (aged 11-13 weeks) were used for the study. Full-thickness flap elevated to exposure calvarial bone. Two 5âmm critical size calvarial defects were created on each rat calvarium. The defects were divided into 4 study groups: 1-Control (nâ=â10); 2- Gelatin sponge+Tideglusib (Gs+TDG; nâ=â10); 3- Autogenous bone (AB; nâ=â10); 4-Autogenous bone+Tideglusib (AB+TDG; nâ=â10). Then, the rats were sacrificed at fourth week. Three-dimensional imaging, histopathologic and immunohistochemical examinations were performed to evaluate the samples. The most increased bone formation and interaction between graft and new bone were observed in AB+TDG group. Bone morphogenic protein-2 (BMP-2), alkaline phosphatase (ALP), collagen type 1 (Col 1) and osteocalcin (OCN) was determined significantly higher in Tideglusib received groups compared with those of Control and AB groups (Pâ<â0.05). Osteoclast numbers found to be higher in Gs+TDG and AB+TDG groups as well as RANKL expression dis not affected in Gs+TDG group but decreased in AB+TDG group comparing those of Control and AB groups. In addition, Tideglusib increased the Bcl-2 levels (Pâ<â0.05) and decreased Bax levels (Pâ>â0.05) in Tideglusib received groups compared with their controls. The administration of Tideglusib in calvarial bone defects increased bone mineral density, new bone area and total bone area by decreasing apoptosis and increasing osteoblastogenesis.
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Regeneración Ósea/efectos de los fármacos , Glucógeno Sintasa Quinasa 3/antagonistas & inhibidores , Inhibidores de Proteínas Quinasas/farmacología , Cráneo/efectos de los fármacos , Tiadiazoles/farmacología , Animales , Masculino , Ratas , Ratas Wistar , Cráneo/cirugíaRESUMEN
Caffeic acid phenethyl ester (CAPE) is used as a therapeutic agent to prevent bone loss. We determined the effects of systemically administered CAPE on alveolar bone loss and oxidative stress in diabetic rats with experimental periodontitis. Forty male rats were divided into four equal groups: control, experimental periodontitis (EP), EP-diabetes mellitus (EP-DM) and EP-DM-CAPE. DM was induced by streptozotocin, then lipopolysaccharide was injected to induce periodontitis. CAPE was administered to the EP-DM-CAPE group daily for 15 days. Then, serum samples were taken and the rats were sacrificed for histological analyses. Serum interleukin (IL-1ß) and oxidative stress also were evaluated. Alveolar bone loss was assessed histomorphometrically. Alveolar bone loss and IL-1ß levels were significantly less in the EP-DM-CAPE and EP groups compared to the EP-DM group. Oxidative stress was significantly less in the EP-DM-CAPE group compared to the EP and EP-DM groups. Receptor activator of nuclear factor kappa-B ligand (RANKL) levels were significantly higher in the EP-DM group compared to the disease groups. CAPE significantly reduced RANKL levels in the EP-DM-CAPE group compared to the EP-DM group. We found that CAPE treatment significantly inhibited DM induced oxidative stress and RANKL induced osteoclastogenesis and alveolar bone loss in diabetic rats with periodontitis.
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Pérdida de Hueso Alveolar/tratamiento farmacológico , Ácidos Cafeicos/farmacología , Diabetes Mellitus Experimental/tratamiento farmacológico , Estrés Oxidativo/efectos de los fármacos , Periodontitis/tratamiento farmacológico , Alcohol Feniletílico/análogos & derivados , Pérdida de Hueso Alveolar/patología , Animales , Diabetes Mellitus Experimental/inducido químicamente , Modelos Animales de Enfermedad , Masculino , Periodontitis/patología , Alcohol Feniletílico/farmacología , Ratas Wistar , Estreptozocina/farmacologíaRESUMEN
The purpose of the present study was to evaluate the contributions of autogenous tooth bone graft (ATBG) combined with platelet-rich fibrin (PRF) on new bone formation and bone morphogenetic protein (BMP)-2 in rabbit calvarial defects. Twelve male New Zealand rabbits were used in this study. Three circular bone defects were prepared in each rabbit with a drill. These defects were divided into 3 groups: control, treated with ATBG, and treated with ATBG+PRF. The animals were sacrificed at 28 days. Samples were evaluated by histomorphometric analyses and total augmented area, new bone area and bone density were calculated. In addition, expression of BMP-2 was determined by immunohistochemical staining. The total augmented area, new bone area and bone density were significantly greater in the ATBG group than in the control group (Pâ<0.05). Also, these values were significantly higher in the ATBG+PRF group than the ATBG group (Pâ<0.05). Test groups demonstrated significantly increased BMP-2 levels compared with the control group (Pâ<0.05). The present study suggested that ATBG combined with PRF significantly increased the new bone formation and enhanced bone healing in cranial defects.
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Trasplante Óseo , Animales , Densidad Ósea , Proteína Morfogenética Ósea 2/metabolismo , Regeneración Ósea , Masculino , Osteogénesis , Fibrina Rica en Plaquetas , Conejos , Trasplante AutólogoRESUMEN
BACKGROUND/PURPOSE: Caffeic acid phenethyl ester (CAPE) is an antioxidant which is decreases the bone resorption and enhances the bone healing. The aim of this study was to investigate the effects of administering systemic CAPE on alveolar bone loss in rats with experimental periodontitis. MATERIALS AND METHODS: Thirty male Sprague Dawley rats were divided into three groups: control, endotoxin-induced periodontitis (EP), and EP treated with CAPE (EP-CAPE). Endotoxin was injected into the gingiva of test rats on days 1, 3, and 5, whereas saline was injected into the control rats. The EP-CAPE group received 10â¯mmol/kg/day CAPE intraperitoneally for 28 consecutive days. Saline was given in the control and EP groups in the same manner. At the end of the study, intracardiac blood samples were obtained, and the rats were sacrificed. Alveolar bone loss was analyzed with histometric measurements. The oxidative stress index (OSI) was used to evaluate the oxidative stress. The receptor activator of the nuclear factor kappa B ligand (RANKL) level was analyzed stereologically. RESULTS: CAPE administration significantly decreased the serum OSI and interleukin-1ß levels. Alveolar bone loss was statistically higher in the EP group compared with the EP-CAPE group (Pâ¯<â¯0.05). Immunohistochemical analyses of the RANKL were significantly lower in the EP-CAPE group than in the EP group (Pâ¯<â¯0.05). CONCLUSION: This experimental study revealed that CAPE administration significantly prevented alveolar bone loss and stimulated periodontal tissue healing.
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The present study evaluates the effects of leukocyte-platelet-rich fibrin (L-PRF) combined with open flap debridement (OFD) on clinical parameters and growth factors levels (GFL) in chronic periodontitis (CP) patients. This trial was registered at clinicaltrials.gov as NCT02594605. 16 patients (32 sites) with chronic periodontitis who had at least two areas of horizontal bone loss, were treated with OFD alone or L-PRF with OFD (OFD + L-PRF). GFL in gingival crevicular fluid (GCF) were analyzed at baseline, 1 week, 2 weeks and 4 weeks after operation. Probing depth (PD) and clinical attachment level (CAL) were measured at baseline and 6 months postoperatively. PD reduction and CAL gain were significantly higher in the OFD + L-PRF sites than in OFD sites. OFD + L-PRF group showed significantly increased bone morphogenetic protein-2 and insulin-like growth factor-1 at 2 weeks compared with baseline. L-PRF combined with OFD significantly increases GFL and thus, it enhances the periodontal healing on CP patients.
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Regeneración Ósea , Periodontitis Crónica/cirugía , Desbridamiento/métodos , Fibrina Rica en Plaquetas , Complicaciones Posoperatorias/epidemiología , Proteína Morfogenética Ósea 2/metabolismo , Desbridamiento/efectos adversos , Encía/metabolismo , Humanos , Factor I del Crecimiento Similar a la Insulina/metabolismo , Colgajos Quirúrgicos/cirugía , Andamios del Tejido/efectos adversos , Andamios del Tejido/química , Cicatrización de HeridasRESUMEN
BACKGROUND: This study evaluates contributions of platelet-rich fibrin (PRF) combined with conventional flap surgery on growth factor levels in gingival crevicular fluid (GCF) and periodontal healing. METHODS: Twenty-six patients (52 sites) with chronic periodontitis were treated either with autologous PRF with open flap debridement (OFD+PRF) or OFD alone. Growth factor levels in GCF at baseline and 2, 4, and 6 weeks after surgery were analyzed, and clinical parameters such as probing depth (PD), relative clinical attachment level (rCAL), and gingival margin level (GML) at baseline and 9 months after surgery were measured. RESULTS: Mean PD reduction and rCAL gain were significantly greater in OFD+PRF sites than in OFD sites. Mean GML change was -0.38 + 0.10 mm in OFD sites and 0.11 + 0.08 mm in the test group; difference between the two groups was statistically significant (P <0.05). Both groups demonstrated increased expression levels of fibroblast growth factor-2, transforming growth factor-ß1, and platelet-derived growth factor-BB at 2 weeks compared with baseline, followed by reductions at 4 and 6 weeks. The OFD+PRF group showed significantly higher growth factor levels compared with the OFD group at 2 and 4 weeks. CONCLUSION: PRF membrane combined with OFD provides significantly higher GCF concentrations of angiogenic biomarkers for ≈2 to 4 weeks and better periodontal healing in terms of conventional flap sites.
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Periodontitis Crónica/terapia , Líquido del Surco Gingival/química , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Fibrina Rica en Plaquetas , Cicatrización de Heridas/fisiología , Adulto , Biomarcadores/metabolismo , Terapia Combinada , Desbridamiento , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Masculino , Persona de Mediana Edad , Índice Periodontal , Colgajos Quirúrgicos , Trasplante Autólogo , Resultado del TratamientoRESUMEN
BACKGROUND: The aim of this study is to evaluate the effects of systemic melatonin treatment on serum oxidative stress index (OSI) and alveolar bone loss (ABL) in rats with diabetes mellitus (DM) and periodontitis. METHODS: Seventy Sprague Dawley rats were divided into control, experimentally induced periodontitis (EP), DM, EP-DM, EP and melatonin treatment (EP-MEL), DM and melatonin treatment (DMMEL), and EP-DM-MEL groups. DM was induced by alloxan, after which periodontitis was induced by ligature for 4 weeks. After removal of the ligature, the rats in the melatonin groups (EP-MEL, DM-MEL, and EP-DM-MEL) were treated with a single dose of melatonin (10 mg/body weight) every day for 14 consecutive days. At the end of the study, all of the rats were euthanized, and intracardiac blood samples and mandible tissues were obtained for biochemical and histologic analyses. Serum levels of total oxidant status/total antioxidant status and OSI were measured. In addition, neutrophil and osteoclast densities and myeloperoxidase activities were determined in gingival tissue homogenates, and ABL was evaluated with histometric measurements. RESULTS: Melatonin treatment significantly reduced fasting plasma glucose levels in the rats with DM. In addition, reduced OSI and ABL levels were detected in the EP-MEL and DM-MEL groups; the reductions in the EP-DM-MEL group were found to be more prominent. Melatonin also significantly decreased the increased myeloperoxidase activities and osteoclast and neutrophil densities in the EP, DM, and EP-DM groups. CONCLUSION: It is revealed in this experimental study that melatonin significantly inhibited hyperglycemia-induced oxidative stress and ABL through antiDM and antioxidant effects in rats with DM and periodontitis.
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Pérdida de Hueso Alveolar/metabolismo , Diabetes Mellitus Experimental , Melatonina/fisiología , Estrés Oxidativo , Periodontitis/fisiopatología , Animales , Antioxidantes , Ratas , Ratas Sprague-Dawley , Ratas WistarRESUMEN
BACKGROUND: The present study aims to investigate the effects of systemic melatonin administration on alveolar bone resorption in experimental periodontitis in rats. METHODS: Twenty-four male Sprague-Dawley rats were divided into three groups (control, experimental periodontitis [Ped], and experimental periodontitis treated with melatonin [Mel-Ped]). For periodontitis induction, first molars were ligatured submarginally for 4 weeks. After ligature removal, rats in the Mel-Ped group were treated with a daily single dose of 10 mg/kg body weight melatonin for 15 consecutive days. At the end of the study, intracardiac blood samples and mandible tissues were obtained for histologic, biochemical, and radiographic analysis. Serum markers related to bone turnover, calcium, phosphorus, bone alkaline phosphatase (b-ALP), and terminal C telopeptide of collagen Type I (CTX) were analyzed. Myeloperoxidase levels were determined in gingival tissue homogenates, and receptor activator of nuclear factor-kappa B ligand (RANKL) activation was analyzed in the mandible samples stereologically. Alveolar bone loss was also evaluated radiographically in the mandible samples of each group. RESULTS: Melatonin treatment decreased serum CTX levels and increased b-ALP levels. Serum calcium and phosphorus levels were not statistically different among groups (P >0.05). Alveolar bone resorption and myeloperoxidase activity were statistically higher in the Ped group compared to the Mel-Ped group (P <0.05). Immunohistochemical staining of RANKL and osteoclast activity were significantly lower in the Mel-Ped group compared to the Ped group (P <0.05). CONCLUSION: This study reveals that melatonin treatment significantly inhibits regional alveolar bone resorption and contributes to periodontal healing in an experimental periodontitis rat model.