Influence of the implant diameter with different sizes of hexagon: Analysis by 3-dimensional finite element method

The aim of this study was to evaluate the stress distribution in implants of regular platforms and of wide diameter with different sizes of hexagon by the 3-dimensional finite element method. We used simulated 3-dimensional models with the aid of Solidworks 2006 and Rhinoceros 4.0 software for the design of the implant and abutment and the InVesalius software for the design of the bone. Each model represented a block of bone from the mandibular molar region with an implant 10 mm in length and different diameters. Model A was an implant 3.75 mm/regular hexagon, model B was an implant 5.00 mm/regular hexagon, and model C was an implant 5.00 mm/ expanded hexagon. A load of 200 N was applied in the axial, lateral, and oblique directions. At implant, applying the load (axial, lateral, and oblique), the 3 models presented stress concentration at the threads in the cervical and middle regions, and the stress was higher for model A. At the abutment, models A and B showed a similar stress distribution, concentrated at the cervical and middle third; model C showed the highest stresses. On the cortical bone, the stress was concentrated at the cervical region for the 3 models and was higher for model A. In the trabecular bone, the stresses were less intense and concentrated around the implant body, and were more intense for model A. Among the models of wide diameter (models B and C), model B (implant 5.00 mm/regular hexagon) was more favorable with regard to distribution of stresses. Model A (implant 3.75 mm/regular hexagon) showed the largest areas and the most intense stress, and model B (implant 5.00 mm/regular hexagon) showed a more favorable stress distribution. The highest stresses were observed in the application of lateral load.

Effect of antimicrobial photodynamic therapy on periodontally infected tooth sockets in rats

The aim of the present study was to evaluate the antimicrobial effect of antimicrobial photodynamic therapy (aPDT) in alveolar treatment of areas with induced periodontitis. Thirty male Wistar rats were subjected to ligature-induced periodontal disease (PD) in the first left inferior molars, while the right side molars did not receive ligatures. After 7 days of PD evolution, ligatures were removed from the left side, and the first left and right mandibular molars were extracted. Afterwards, animals were divided into groups according to the following treatments: control (C)-no treatment; mechanical debridement (MD)-mechanical debridement and irrigation with saline solution; and aPDT-mechanical debridement, irrigation with toluidine blue O (TBO), and 1 min of laser irradiation (GaAlAs, 660 nm, 30 mW, 32 J/cm2, 60 s). Ligatures were removed and samples of the alveolar content after extraction and after each treatment were collected for microbial processing by real-time polymerase chain reaction with specific primers for Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, and Treponema denticola. Data were submitted to statistical analysis by multiple comparison tests (McNemar test; p < 0.05). T. denticola was not found in the collected samples. A. actinomycetemcomitans and P. gingivalis were found in ligature samples. Tooth socket samples without periodontitis induction presented lesser microbial charge than samples with induced periodontitis (p < 0.05). aPDT significantly reduced A. actinomycetemcomitans levels on the left side (p < 0.05). It was concluded that aPDT was an effective antimicrobial treatment for tooth sockets in areas affected by induced periodontitis. © 2013 Springer-Verlag London.

Effect of the treatment of root surface-adhered necrotic periodontal ligament with propolis or fluoride in delayed rat tooth replantation

Objectives: The purpose of this study was to evaluate the application of 15 % propolis and 2 % acidulated-phosphate sodium fluoride solutions on the root surface-adhered necrotic cemental periodontal ligament in delayed tooth replantation. Materials and methods: Thirty Wistar rats (Rattus norvegicus, albinus) had their right upper incisor extracted and maintained in dry storage for 60 min. After this period, the dental papilla, enamel organ, and pulp tissue were removed, and the animals were randomly assigned to three groups: group I = immersion in saline for 10 min; group II = immersion in a 2 % acidulated-phosphate sodium fluoride solution for 10 min; and group III = immersion in a 15 % propolis and propylene glycol solution for 10 min. The root canals were filled with a calcium hydroxide paste and the teeth were replanted. Results: Inflammatory resorption, replacement resorption, and ankylosis were observed in all groups without a statistically significant difference (p > 0.05) among them. Conclusions: Under the tested conditions, the application of fluoride or propolis on root surface-adhered necrotic periodontal ligament did not favor the healing process in delayed tooth replantation. © 2013 Springer-Verlag Berlin Heidelberg.

Dimensões do corredor bucal em diferentes faixas etárias e sua proporção com a distância inter pré-molar e inter comissura

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Hipomineralização molar incisivo em escolares de Botelhos, Minas Gerais, Brasil

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Identificação precoce de neoplasia trofoblástica pós-molar pela curva de regressão normal da gonadotrofina coriônica humana

Pós-graduação em Ginecologia, Obstetrícia e Mastologia - FMB

Comportamento radiográfico dos terceiros molares inferiores em pacientes tratados ortodonticamente com e sem extrações de primeiros pré-molares

Pós-graduação em Odontologia - FOA

Aplicação de ondas de ultra-som sobre cimentos de ionômero de vidro: rugosidade superficial e perda de massa após ensaio de escovação

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Temperatura superficial e interna de cimentos de ionômeros de vidro e transmissão à câmara pulpar: aplicação de ondas de ultrassom

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Alterações cefalométricas induzidas pelo aparelho de Herbst com dois tipos de ancoragem para maxila

Pós-graduação em Ciências Odontológicas - FOAR

Análise comparativa da movimentação dentária induzida entre dois critérios de mensuração: macroscópico e microscópico

Pós-graduação em Odontologia - FOA

Comportamento transversal de caninos e segundos molares decíduos após a correção da mordida cruzada posterior com quadrihélice

Pós-graduação em Odontologia - FOA

Avaliação da reabsorção radicular após a movimentação dentária induzida com forças contínua e contínua interrompida: análise histomorfométrica em ratos

Pós-graduação em Odontologia - FOA

Marcação fluorescente de cálcio em tecidos de suporte após a movimentação dentária experimental em ratos

Pós-graduação em Odontologia - FOA

Avaliação da intrusão dos molares superiores pela técnica de ancoragem com miniplacas de titânio

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)