Vital Bone Formation After Grafting of Autogenous Bone and Biphasic Calcium Phosphate Bioceramic in Extraction Sockets of Rats: Histological, Histometric, and Immunohistochemical Evaluation.

PURPOSE: The study aimed to investigate through histology, histometry, and immunohistochemistry the vital bone formation after grafting of biphasic calcium phosphate bioceramic (BC) in combination with calvarial autogenous bone into the dental sockets of rats. MATERIALS AND METHODS: Forty-five male rats were submitted to upper right incisor extraction and divided according to the grafted material in: control, bioceramic (BC), and bioceramic + autogenous bone (BC + AB). The animals were killed 7, 21, and 42 days after surgery for histological, histometric, and immunohistochemistry analysis. RESULTS: Histomorphometric results demonstrated, for BC + AB group, formation of trabecular bone between the particles of BCs and autogenous bone, connecting them, as well as higher percentage of vital bone in comparison with BC. Immunohistochemical reactions showed intense labeling for Runx2-positive cells in the group BC + AB. CONCLUSIONS: Autogenous bone was able to stimulate bone turnover enabling a larger amount of vital bone synthesis and can be recommended as a viable grafting material in combination with synthetic biphasic BC.

Dimensional changes from the sintering process and fit of Y-TZP copings: Micro-CT analysis.

OBJECTIVE: To evaluate the dimensional changes from the sintering process of Y-TZP and relate them to the fit of zirconia copings. METHODS: The sintering shrinkage rate (SSR) was obtained from the measurement of geometric specimens (4×4×2mm). Thirty-six zirconia copings made using CAD/CAM were equally divided into three groups (n=12): ZMAX - IPS e.max ZirCAD (Ivoclar Vivadent, Liechtenstein); ZYZ - InCeram YZ (Vita Zahnfabrik, Germany); and ZK - Zirklein (Zirklein, Brazil). The copings were scanned in micro-CT before and after sintering so that SSR was obtained. The SSR of geometrical specimens and copings was compared to each other and those the manufacturers reported (ANOVA-2 and Tukey, p≤.05). The copings were settled on an abutment and taken to the micro-CT to evaluate their marginal and internal fit. The data enabled the statistical comparison (ANOVA-2 and Tukey, p≤.05) between groups and measurement sites and between the fit obtained with that stipulated by the CAD/CAM software (80µm) (Dunnett test, p≤.05). RESULTS: All groups showed statistical differences between the SSR the manufacturer reported and those obtained experimentally and between the SSR of the geometric specimens and copings. In general, the SSR of the copings showed no uniformity. There was no statistical difference among the groups for marginal fit, with differences only for internal fit and between the different regions measured. The fit obtained experimentally differed from the internal space determined in the CAD/CAM software. SIGNIFICANCE: The lack of uniformity of sintering shrinkage might lead to a non-uniform internal fit of Y-TZP copings.

Effects of coffee intake and intraperitoneal caffeine on bone repair process--a histologic and histometric study.

Studies have suggested that caffeine acts on bone promoting an increase of calcium excretion, inhibition of osteoblast proliferation and delay in tissue repair process, raising the risk of fractures, osteoporosis, periodontal disease and affecting the success of bone reconstructive procedures. The aim of this study was to analyze histomorphometrically the process of alveolar bone healing after tooth extraction in rats subjected to daily intake of boiled coffee or intraperitoneal administration of caffeine. Forty-five male rats were divided according to the treatment in Control group (C); Coffee group (CO) - treated with coffee since birth; and Caffeine (CAF) - intraperitoneal injection of aqueous solution of caffeine 1.5% (0.2 mL/100g body weight) for 30 days. When weighing between 250-300 g they were anesthetized, subjected to extraction of the maxillary right incisor, and euthanized 7, 21 and 42 days after surgery for histological assessments of bone volume and the quality of formed bone in the dental socket. The qualitative results demonstrated larger amounts of blood clot and immature bone in animals under treatment of pure caffeine compared to coffee and control. Histometric analysis revealed that coffee treatment led to a 40% drop in bone formation, and caffeine a 60% drop in comparison to control animals (ANOVA p≤0.01). It was concluded that both the daily ingestion of coffee and the intraperitoneal administration of caffeine in rats delayed the alveolar bone reparative process after tooth extraction, and this effect was more aggressive when pure caffeine was used.

Effects of Coffee Intake and Intraperitoneal Caffeine on Bone Repair Process - A Histologic and Histometric Study

Studies have suggested that caffeine acts on bone promoting an increase of calcium excretion, inhibition of osteoblast proliferation and delay in tissue repair process, raising the risk of fractures, osteoporosis, periodontal disease and affecting the success of bone reconstructive procedures. The aim of this study was to analyze histomorphometrically the process of alveolar bone healing after tooth extraction in rats subjected to daily intake of boiled coffee or intraperitoneal administration of caffeine. Forty-five male rats were divided according to the treatment in Control group (C); Coffee group (CO) - treated with coffee since birth; and Caffeine (CAF) - intraperitoneal injection of aqueous solution of caffeine 1.5% (0.2 mL/100g body weight) for 30 days. When weighing between 250-300 g they were anesthetized, subjected to extraction of the maxillary right incisor, and euthanized 7, 21 and 42 days after surgery for histological assessments of bone volume and the quality of formed bone in the dental socket. The qualitative results demonstrated larger amounts of blood clot and immature bone in animals under treatment of pure caffeine compared to coffee and control. Histometric analysis revealed that coffee treatment led to a 40% drop in bone formation, and caffeine a 60% drop in comparison to control animals (ANOVA p≤0.01). It was concluded that both the daily ingestion of coffee and the intraperitoneal administration of caffeine in rats delayed the alveolar bone reparative process after tooth extraction, and this effect was more aggressive when pure caffeine was used.

Estudos têm sugerido que a cafeína age sobre o osso promovendo um aumento da excreção de cálcio, inibição da proliferação dos osteoblastos e retardo no processo de reparação tecidual, aumentando o risco de fraturas, osteoporose, doença periodontal, bem como afetando o sucesso de procedimentos de reconstrução óssea. O objetivo deste estudo foi analisar histomorfometricamente o processo de reparação óssea alveolar após extração dentária em ratos submetidos à ingestão diária de café fervido ou a administração intraperitoneal de cafeína. 45 ratos machos foram divididos de acordo com o tratamento, em controle (C); café (CO), tratados com café desde o nascimento; e cafeína (CAF), injeção intraperitoneal de solução aquosa de cafeína de 1,5 % (0,2 mL/100 g de peso corporal) durante 30 dias. Quando pesavam entre 250-300 g os animais foram anestesiados, submetidos à extração do incisivo superior direito, e sacrificados em 7, 21 e 42 dias após a cirurgia para análises histológicas quanto ao volume e à qualidade do osso formado no alvéolo dental. Os resultados qualitativos demonstraram grandes quantidades de coágulo sanguíneo e osso imaturo nos animais tratados com cafeína pura, em relação aos grupos café e controle. A avaliação histométrica mostrou que o tratamento com o café levou a uma queda na formação óssea de 40%, e com a cafeína de 60% em comparação ao grupo controle (ANOVA p≤0,01). Concluiu-se que tanto a ingestão diária de café quanto a administração intraperitoneal de cafeína em ratos retardou o processo de reparação do osso alveolar após extração dentária, e este efeito é mais agressivo quando do uso da cafeína pura.

Bone integration behavior of hydroxyapatite/ß-tricalcium phosphate graft implanted in dental alveoli: a histomorphometric and scanning electron microscopy study.

PURPOSE: This study investigated the bone integration ability of a biphasic calcium phosphate bioceramic implanted in dental alveolus of rats. MATERIALS AND METHODS: A total of 21 male rats were submitted to upper right incisor extraction and implanted with a synthetic bioceramic (Straumann Bone Ceramic). The animals were killed on 7th, 21st, and 42nd day after surgery for light and scanning electron microscopy (SEM) analysis of bone, bioceramic, and soft tissue volume as well as the quality of graft in its interface. RESULTS: Light histology results showed no persistent inflammatory and foreign body reactions, a newly formed bone adhered on the ceramic surface without interposition of soft tissue, which was confirmed by SEM analysis. Histometrically, reduction/resorption, between 7 and 42 days, in the percentage of bioceramic implanted (α = 1%) left gaps for a gradual increase in vital bone formation (α = 1%) around the particles. CONCLUSIONS: The bioceramic in question is biocompatible, has good bone integration, being gradually resorbed and replaced by it, featuring a viable bone substitute for grafting procedures.

Osteointegration of autogenous bone graft associated with osteoblastic cells under treatment with caffeine.

PURPOSE: The present study investigated osteointegration of autogenous bone (AB) from calvaria graft associated with osteoblastic cells (OC) in bone defects in rats subjected to daily administration of caffeine. MATERIALS AND METHODS: Male rats received daily intraperitoneal injection of 1.5% caffeine (0.2 mL/100 g body weight) or saline solution for 30 days. Then they were anesthetized, submitted to the extraction of the upper right incisor, and implanted with AB only and AB + OC. The animals were killed on 7th, 21st, and 42nd days after surgery, and their maxilla were processed for obtaining semiserial sections (5 µm) stained with hematoxylin and eosin. Through image analysis system, the bone volume and the quality of graft in adjacent areas were estimated. RESULTS: The results showed that in caffeine treatment, the AB + OC graft showed no foreign body and acute inflammatory reactions inside the defect when compared to AB. The histometric results revealed that the association AB + OC produced significant increase (10%-15%) in bone volume in later experimental period (42 days) when compared with saline solution group (P ≤ 0.01). CONCLUSIONS: It was concluded that the association of AB from calvaria + OC demonstrated progressive osteointegration and accelerated the repair of bone defects in animals treated with daily caffeine.

Bone quality associated with daily intake of coffee: a biochemical, radiographic and histometric study.

Caffeine induces loss of calcium and influences the normal development of bone. This study investigated the effects of coffee on bone metabolism in rats by biochemical measurement of calcium, bone densitometry and histometry. Male rats, born of female treated daily with coffee and with coffee intake since born, were anesthetized, subjected to extraction of the upper right incisor, and sacrificed 7, 21 and 42 days after surgery. Blood and urine samples were taken, and their maxilla radiographed and processed to obtain 5-µm-thick semi-serial sections stained with hematoxylin and eosin. The volume and bone quality were estimated using an image-analysis software. The results showed significantly greater amount of calcium in the plasma (9.40 ± 1.73 versus 9.80 ± 2.05 mg%) and urine (1.00 ± 0.50 versus 1.25 ± 0.70 mg/24 h) and significantly less amount in bone (90.0 ± 1.94 versus 86.0 ± 2.12 mg/mg bone), reduced bone mineral density (1.05 ± 0.11 versus 0.65 ± 0.15 mmAL), and lower amount of bone (76.19 ± 1.6 versus 53.41 ± 2.1 %) (ANOVA; p≤0.01) in animals treated with coffee sacrificed after 42 days. It may be concluded that coffee/caffeine intake caused serious adverse effects on calcium metabolism in rats, including increased levels of calcium in the urine and plasma, decreased bone mineral density and lower volume of bone, thus delaying the bone repair process.

Bone quality associated with daily intake of coffee: a biochemical, radiographic and histometric study

Caffeine induces loss of calcium and influences the normal development of bone. This study investigated the effects of coffee on bone metabolism in rats by biochemical measurement of calcium, bone densitometry and histometry. Male rats, born of female treated daily with coffee and with coffee intake since born, were anesthetized, subjected to extraction of the upper right incisor, and sacrificed 7, 21 and 42 days after surgery. Blood and urine samples were taken, and their maxilla radiographed and processed to obtain 5-µm-thick semi-serial sections stained with hematoxylin and eosin. The volume and bone quality were estimated using an image-analysis software. The results showed significantly greater amount of calcium in the plasma (9.40 ± 1.73 versus 9.80 ± 2.05 mg percent) and urine (1.00 ± 0.50 versus 1.25 ± 0.70 mg/24 h) and significantly less amount in bone (90.0 ± 1.94 versus 86.0 ± 2.12 mg/mg bone), reduced bone mineral density (1.05 ± 0.11 versus 0.65 ± 0.15 mmAL), and lower amount of bone (76.19 ± 1.6 versus 53.41 ± 2.1 percent) (ANOVA; p≤0.01) in animals treated with coffee sacrificed after 42 days. It may be concluded that coffee/caffeine intake caused serious adverse effects on calcium metabolism in rats, including increased levels of calcium in the urine and plasma, decreased bone mineral density and lower volume of bone, thus delaying the bone repair process.

A cafeína induz perda de cálcio e influencia no desenvolvimento ósseo normal. Este estudo investiga os efeitos do café sobre o metabolismo ósseo em ratos através de avaliações bioquímicas do cálcio, densitometria e histometria óssea. Ratos machos, nascidos de fêmeas tratadas diariamente com café, e com ingestão de café desde o nascimento, foram anestesiados, submetidos à extração do incisivo superior direito e sacrificados 7, 21 e 42 dias após a cirurgia. Amostras de sangue e urina foram colhidas, suas maxilas radiografadas e processadas para se obter cortes semi seriados (5 µm) e corados pela hematoxilina-eosina. Através de um programa de análise de imagens, o volume e a qualidade do osso foram avaliados. Os resultados demonstraram maior quantidade de cálcio no sangue (9,40 ± 1,73 versus 9,80 ± 2,05 mg por cento) e urina (1,00 ± 0,50 versus 1,25 ± 0,70 mg/24 h) e menor no osso (90,0 ± 1,94 versus 86,0 ± 2,12 mg/mg osso), densidade mineral óssea menor (1,05 ± 0,11 versus 0,65 ± 0,15 mmAL), e menor quantidade de osso (76,19 ± 1,6 versus 53,41 ± 2,1 por cento) estatisticamente significante (ANOVA p≤0,01) nos animais tratados com café sacrificados após 42 dias. Conclui-se que a ingestão de café/cafeína causou sérios efeitos adversos no metabolismo de cálcio em ratos, incluindo aumento dos níveis de cálcio na urina e no plasma, diminuição da densidade mineral óssea e menor volume de osso atrasando o processo de reparo ósseo.