Hyperbaric Oxygen therapy effects on bone regeneration in Type 1 diabetes mellitus in rats.

PURPOSE: The aim of this study was evaluate the effect of HBO on diabetic rats. MATERIALS AND METHODS: Twenty rats were distributed into four groups (n = 5): Control (C); Control + HBO (CH); Diabetes (D) and Diabetes + HBO (DH). Diabetes was induced by streptozotocin, and bone defects were created in both femurs in all animals. HBO therapy began immediately after surgery and was performed daily in the CH and DH groups. After 7 days, the animals were euthanized. The femurs were removed, demineralized, embedded in paraffin, and histologic images were analyzed. RESULTS: Qualitative histologic analyses showed more advanced stage bone regeneration in control groups (C and CH) compared with diabetic groups (D and DH). Histomorphometric analysis showed significantly increased bone neoformation in CH compared with the other groups (p < 0.001). Diabetic Group (D) showed decreased bone neoformation compared with non-diabetic groups (C and CH) (p < 0.001); however DH did not differ from C Group (p > 0.05). The mast cell population increased in CH compared with the other groups (C, D, and DH) (p < 0.05). The mast cell population did not differ between D and DH Groups. CONCLUSIONS: This study showed that HBO therapy improved early bone regeneration in diabetic rats and increased the mast cell population only in non-diabetic animals. HBO was shown to be important treatment for minimizing deleterious effects of diabetes on bone regeneration.

Local Drug Delivery Systems in the Treatment of Periodontitis: A Literature Review.

In order to complement non-surgical therapy in periodontitis, there are multiple options of antimicrobials, such as metronidazole, chlorhexidine, minocycline, doxycycline and tetracycline, which can be locally delivered into the mucosa. These drugs are used in periodontal pockets and can inhibit or eliminate periodontopathogenic microorganisms as well as modulate the inflammatory response of tissues. However, limited data are available concerning the relationship between effect, efficacy and clinical status of the periodontium. This review aims to evaluate the effect and the efficacy of five types of local drug delivery systems in clinical parameters of periodontology. Researched papers using MEDLINE via PubMed, and LILACS databases related to five types of local drug delivery systems as chlorhexidine gluconate, doxycycline hyclate, metronidazole gel, minocycline ointment and tetracycline fibers, were reviewed aiming to address the mechanism of action and the evidence of clinical effectiveness of adjunctive use of these antimicrobials following surgical and/or non-surgical therapies. Inclusion criteria defined that articles must be randomized controlled trials performed in humans and published between 1996 and 2014. The adjunctive use of local drug delivery systems with controlled release properties may provide a defined, but limited, beneficial response on periodontal pockets. Furthermore, local drug delivery as an active treatment or maintenance therapy depends on clinical findings, responses to treatment described in the literature, desired clinical outcomes, and patients' dental and medical histories, including their past usage of antimicrobials.

High doses of ionizing radiation on bone repair: is there effect outside the irradiated site?

Local ionizing radiation causes damage to bone metabolism, it reduces blood supply and cellularity over time. Recent studies indicate that radiation promotes biological response outside the treatment field. The aim of this study was to investigate the effects of ionizing radiation on bone repair outside the irradiated field. Ten healthy male Wistar rats were used; and five animals were submitted to radiotherapy on the left femur. After 4 weeks, in all animals were created bone defects in the right and left femurs. Seven days after surgery, animals were euthanized. The femurs were removed and randomly divided into 3 groups (n=5): Control (C) (right femur of the non-irradiated animals); Local ionizing radiation (IR) (left femur of the irradiated animals); Contralateral ionizing radiation (CIR) (right femur of the irradiated animals). The femurs were processed and embedded in paraffin; and bone histologic sections were evaluated to quantify the bone neoformation. Histomorphometric analysis showed that there was no significant difference between groups C (24.6±7.04) and CIR (25.3±4.31); and IR group not showed bone neoformation. The results suggest that ionizing radiation affects bone repair, but does not interfere in bone repair distant from the primary irradiated site.

Different approaches for aesthetic rehabilitation of discolored nonvital anterior teeth / Diferentes abordagens para reabilitação estética de dentes anteriores escurecidos não-vitais

ABSTRACT An ideal aesthetic standard consists of facial and smile harmony. Discolored teeth generally cause an imbalance in facial aesthetics, leading to low self-esteem and disturbance in social relationships. Causes of teeth discoloration are classified as intrinsic or extrinsic. Bleaching is considered a safe and effective treatment for discolored nonvital teeth and can be associated with restorative treatment to properly correct the dental color and maximize the aesthetic results. This paper aims to present two case reports of single discolored nonvital anterior teeth and the protocol used to reestablish the dental harmony of these patients by bleaching and direct composite resin restoration. To exert minimally invasive dentistry is very important to preserve tooth structure and reduce the risk of fracture. Internal bleaching, although may not be sufficient to reestablish the aesthetic in some cases, it is important to minimize dental preparation to perform an indirect or direct restoration. Dentists must take into account the patients expectations, dominate the restorative technique and know the dental materials to properly be able to restore function and aesthetics and consequently improve life quality and social relationships.

RESUMO Um padrão estético ideal consiste na harmonia facial e do sorriso. Dentes descoloridos geralmente causam um desequilíbrio na estética facial, levando a baixa auto-estima e interferência nas relações sociais. As causas da descoloração dos dentes são classificadas como intrínsecas ou extrínsecas. O clareamento é considerado um tratamento seguro e eficaz para os dentes não vitais escurecidos e pode ser associado ao tratamento restaurador para corrigir adequadamente a cor dental e maximizar os resultados estéticos. O objetivo deste trabalho é apresentar dois relatos de casos de dentes anteriores não vitais escurecidos e o protocolo utilizado para restabelecer a harmonia dentária desses pacientes por meio de clareamento e restauração direta em resina composta. Para exercer uma Odontologia minimamente invasiva é muito importante preservar a estrutura dentária e reduzir o risco de fratura. O clareamento interno, embora possa não ser suficiente para restabelecer a estética em alguns casos, é importante para minimizar o preparo dental para realizar uma restauração indireta ou direta. Os dentistas devem levar em consideração as expectativas dos pacientes, dominar a técnica restauradora e conhecer os materiais dentários para poder restaurar adequadamente a função e a estética e, consequentemente, melhorar a qualidade de vida e as relações sociais.