RESUMO
The interradicular region of primary molars is permeated by many foramina, channels and accessories that connect the pulp cavity with the periapical tissues anatomically. Thus, pulp decomposition products or drugs used in endodontic treatment can trigger inflammatory reactions. The aim of this study was to evaluate the blood cell profile of the alveolar region after extraction of primary molars treated with CTZ paste. Forty-eight primary molars were selected with clinical and radiographic signs of extraction. The sample was divided into three groups with 16 teeth each: Group 1-healthy teeth; Group 2-untreated decayed teeth; and Group 3-teeth treated with CTZ paste. Immediately after the extraction, blood from the interface of the tooth socket was collected and smears were performed for further evaluation. The slides were stained by the Fast Panoptic® method and analysed by two previously trained examiners who counted the leucocytes in sets of 100 cells/slide, differentiating them into neutrophils, lymphocytes, monocytes, eosinophils and basophils. The data were analysed statistically by the MANOVA test. The blood samples from Group 2 differed significantly from Group 1 samples for all classes of leucocytes, except basophils, with higher average for lymphocytes (62.56), monocytes (7.81) and eosinophils (2.31). For Group 3, there was a relative difference (P < 0.05) to Group 2, of monocytes and eosinophils values. The blood cellularity interface in the tooth socket of primary teeth treated with CTZ paste is similar to those of healthy, exfoliated teeth and physiologically different from untreated decayed teeth.
Assuntos
Antibacterianos/uso terapêutico , Necrose da Polpa Dentária/tratamento farmacológico , Dente Molar/efeitos dos fármacos , Dente Decíduo/diagnóstico por imagem , Antibacterianos/administração & dosagem , Criança , Estudos Transversais , Necrose da Polpa Dentária/sangue , Humanos , Leucócitos/patologia , Dente Molar/irrigação sanguínea , Dente Molar/diagnóstico por imagem , Dente Molar/patologia , Pomadas , Alvéolo Dental/diagnóstico por imagem , Alvéolo Dental/patologia , Dente Decíduo/efeitos dos fármacosRESUMO
INTRODUCTION: Nicotine is harmful to angiogenesis, osteogenesis and synthesis of collagen. OBJECTIVE: The aim of this study was to investigate the effect of nicotine on bone remodeling during orthodontic movement in rats. METHODS: Eighty male Wistar rats were randomly divided into three groups: Group C (control), group CM (with orthodontic movement) and group NM (nicotine with orthodontic movement) groups. The animals comprising groups C and CM received 0.9% saline solution while group NM received nicotine solution (2 mg/kg). A nickel-titanium closed-coil spring was used to induce tooth movement. The animals were euthanized and tissue specimens were histologically processed. Blood vessels, Howship's lacunae and osteoclast-like cells present in the tension and compression areas of periodontal ligaments were quantified. The extent of bone formation was evaluated under polarized light, to determine the percentage of immature/mature collagen. RESULTS: It was observed lower blood vessel densities in the NM group in comparison to the CM group, three (p < 0.001) and seven (p < 0.05) days after force application. Osteoclast-like cells and Howship's lacunae in the NM group presented lower levels of expression, in comparison to the CM group, with significant differences on day 7 (p < 0.05 for both variables) and day 14 (p < 0.05 for osteoclast-like cells and p < 0.01 for Howship's lacunae). The percentage of immature collagen was increased in the NM group in comparison to the CM group, with a statistically significant difference on day 3 (p < 0.05), day 7 (p < 0.001), day 14 (p < 0.001) and day 21 (p < 0.001). CONCLUSIONS: Nicotine affects bone remodeling during orthodontic movement, reducing angiogenesis, osteoclast-like cells and Howship's lacunae, thereby delaying the collagen maturation process in new bone matrix.
Assuntos
Processo Alveolar/efeitos dos fármacos , Remodelação Óssea/efeitos dos fármacos , Nicotina/farmacologia , Ligamento Periodontal/efeitos dos fármacos , Técnicas de Movimentação Dentária , Processo Alveolar/irrigação sanguínea , Animais , Reabsorção Óssea/patologia , Colágeno/efeitos dos fármacos , Ligas Dentárias/química , Cemento Dentário/irrigação sanguínea , Cemento Dentário/efeitos dos fármacos , Masculino , Dente Molar/irrigação sanguínea , Dente Molar/efeitos dos fármacos , Neovascularização Fisiológica/efeitos dos fármacos , Níquel/química , Fios Ortodônticos , Osteoclastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Ligamento Periodontal/irrigação sanguínea , Distribuição Aleatória , Ratos , Ratos Wistar , Estresse Mecânico , Fatores de Tempo , Titânio/química , Técnicas de Movimentação Dentária/instrumentação , Raiz Dentária/irrigação sanguínea , Raiz Dentária/efeitos dos fármacosRESUMO
Introduction: Nicotine is harmful to angiogenesis, osteogenesis and synthesis of collagen. Objective: The aim of this study was to investigate the effect of nicotine on bone remodeling during orthodontic movement in rats. Methods: Eighty male Wistar rats were randomly divided into three groups: Group C (control), group CM (with orthodontic movement) and group NM (nicotine with orthodontic movement) groups. The animals comprising groups C and CM received 0.9% saline solution while group NM received nicotine solution (2 mg/kg). A nickel-titanium closed-coil spring was used to induce tooth movement. The animals were euthanized and tissue specimens were processed histologically. We quantified blood vessels, Howship's lacunae and osteoclast-like cells present in the tension and compression areas of periodontal ligaments. The extent of bone formation was evaluated under polarized light to determine the percentage of immature/mature collagen. Results: We observed lower blood vessel densities in the NM group in comparison to the CM group, three (p < 0.001) and seven (p < 0.05) days after force application. Osteoclast-like cells and Howship's lacunae in the NM group presented lower levels of expression in comparison to the CM group, with significant differences on day 7 (p < 0.05 for both variables) and day 14 (p < 0.05 for osteoclast-like cells and p < 0.01 for Howship's lacunae). The percentage of immature collagen increased in the NM group in comparison to the CM group with a statistically significant difference on day 3 (p < 0.05), day 7 (p < 0.001), day 14 (p < 0.001) and day 21 (p < 0.001). Conclusions: Nicotine affects bone remodeling during orthodontic movement, reducing angiogenesis, osteoclast-like cells and Howship's lacunae, thereby delaying the collagen maturation process in developed bone matrix. .
Introdução: a nicotina apresenta efeito prejudicial sobre a angiogênese, osteogênese e síntese de colágeno. Objetivo: investigar a ação da nicotina sobre a remodelação óssea durante o movimento dentário induzido em ratos. Métodos: oitenta ratos machos Wistar foram divididos em três grupos: grupo C (sem indução de movimento dentário e sem a ação da nicotina - controle); grupo CM (indução de movimento dentário) e grupo NM (indução de movimento dentário associado à ação da nicotina). Os animais dos grupos C e CM receberam solução salina a 0,9% e os animais do grupo NM receberam nicotina (solução PA a 98% diluída em solução salina a 0,9% estéril) por via subcutânea (2mg/kg). Após a eutanásia dos animais, com 3, 7, 14 e 21 dias de uso da mola ortodôntica, os espécimes teciduais foram processados histologicamente e quantificou-se o número de vasos sanguíneos, lacunas de Howship e células osteoclásticas nos lados de tração e compressão do ligamento periodontal. A neoformação óssea foi avaliada por meio de luz polarizada, para determinar a porcentagem de colágeno maduro e imaturo. Resultados: observou-se que a quantidade de vasos sanguíneos diminuiu no grupo NM, quando comparado ao grupo CM, nos períodos de três (p < 0,001) e sete (p < 0,05) dias. Quanto às células osteoclásticas e lacunas de Howship, o grupo NM apresentou menores níveis de expressão em relação ao grupo CM, com diferença estatisticamente significativa nos períodos de 7 e 14 dias. A porcentagem de colágeno imaturo apresentou-se aumentada no grupo NM, quando comparado ao grupo CM, em todos os períodos analisados, com diferença e...