Flap vs. "flapless" surgical approach at immediate implants: A histomorphometric study in dogs

Aim: To compare the remodeling of the alveolar process at implants installed immediately into extraction sockets by applying a flap or a "flapless" surgical approach in a dog model.Material and methods: Implants were installed immediately into the distal alveoli of the second mandibular premolars of six Labrador dogs. In one side of the mandible, a full-thickness mucoperiosteal flap was elevated (control site), while contra-laterally, the mucosa was gently dislocated, but not elevated (test site) to disclose the alveolar crest. After 4 months of healing, the animals were sacrificed, ground sections were obtained and a histomorphometric analysis was performed.Results: After 4 months of healing, all implants were integrated (n=6). Both at the test and at the control sites, bone resorption occurred with similar outcomes. The buccal bony crest resorption was 1.7 and 1.5 mm at the control and the test sites, respectively.Conclusions: "Flapless" implant placement into extraction sockets did not result in the prevention of alveolar bone resorption and did not affect the dimensional changes of the alveolar process following tooth extraction when compared with the usual placement of implants raising mucoperiosteal flaps. © 2010 John Wiley & Sons A/S.link_to_subscribed_fulltex

Effects of enamel matrix derivative and transforming growth factor-beta 1 on human periodontal ligament fibroblasts

Aim: The objective of this study was to evaluate the effects of enamel matrix derivative (EMD), transforming growth factor-beta 1 (TGF-beta 1), and a combination of both factors (EMD+TGF-beta 1) on periodontal ligament (PDL) fibroblasts. Material and methods: Human PDL fibroblasts were obtained from three adult patients with a clinically healthy periodontium, using the explant technique. The effects of EMD, TGF-beta 1, or a combination of both were analysed on PDL cell proliferation, adhesion, wound healing, and total protein synthesis, and on alkaline phosphatase (ALP) activity and bone-like nodule formation. Results: Treatment with EMD for 4, 7, and 10 days increased cell proliferation significantly compared with the negative control (p < 0.05). At day 10, EMD and EMD+TGF-beta 1 showed a higher cell proliferation compared with TGF-beta 1 (p < 0.01). Cell adhesion was significantly up-regulated by TGF-beta 1 compared with EMD and EMD+TGF-beta 1 (p < 0.01). EMD enhanced in vitro wound healing of PDL cells compared with the other treatments. Total protein synthesis was significantly increased in PDL cells cultured with EMD compared with PDL cells treated with TGF-beta 1 or EMD+TGF-beta 1 (p < 0.05). EMD induced ALP activity in PDL fibroblasts, which was associated with an increase of bone-like nodules. Conclusion: These findings support the hypothesis that EMD and TGF-beta 1 may play an important role in periodontal regeneration. EMD induced PDL fibroblast proliferation and migration, total protein synthesis, ALP activity, and mineralization, while TGF-beta 1 increased cellular adhesion. However, the combination of both factors did not positively alter PDL fibroblast behaviour.34651452

Comparison of motor strength and function in patients with Duchenne muscular dystrophy with or without steroid therapy Comparação da força e função motora em pacientes com distrofia muscular de Duchenne com ou sem corticoterapia

OBJECTIVE: To compare muscle strength (MS) and motor function in patients with Duchenne muscular dystrophy (DMD) receiving steroids for different times against the natural evolution of DMD described by Scott et al. METHOD: 90 patients with DMD (aged 5- 12 years), receiving steroids for one to seven years, were evaluated by Medical Research Council Scale (MRC) and Hammersmith motor ability score. The relation between MS and motor abilities measurement from our data and Scott's ones were ascertained statistically. RESULTS: The relation between patient's age and Hammersmith scores revealed decrease of 0.76 point per year for age against decrease of 2.23 points on Scott's study. The relation between MRC scale and patient's age showed decrease of 0.80 point per year of age against decrease of 3.65 points on Scott's study. CONCLUSION: In patients with DMD aged five to 12 years the progression of the disease is delayed by steroids and the motor function is less reduced than muscular strength.<br>OBJETIVO: Comparar força muscular e função motora de pacientes com distrofia muscular de Duchenne (DMD) em corticoterapia com a evolução natural da doença descrita por Scott et al. MÉTODO: Noventa pacientes, entre 5 e 12 anos de idade, em corticoterapia por um até sete anos, foram avaliados quanto à força muscular (FM) (escala MRC) e função motora (Hammersmith motor ability score). A relação entre idade, FM e função motora e a comparação com o estudo de Scott et al foram determinadas estatisticamente. RESULTADOS: a relação idade/escore Hammersmith diminuiu 0,76 pontos a cada ano de aumento da idade (2,23 pontos na história natural). A relação idade/MRC decresceu 0,80 pontos a cada ano de aumento da idade (3,65 pontos na história natural). CONCLUSÃO: Nos pacientes em corticoterapia, a progressão da doença é mais lenta que na evolução natural em todas as faixas etárias avaliadas, sendo a FM mais comprometida que a função motora

Occupational exposure to acid mists and periodontal attachment loss Exposição ocupacional a névoas ácidas e perda de inserção periodontal

This study investigated the hypotheses that occupational exposure to acid mists is positively associated with periodontal disease, assessed by periodontal attachment loss. The study sample included 530 male workers at a metal processing factory. Data were obtained from interviews and oral examinations. Periodontal attachment loss was defined as > 4mm at probing, in at least one tooth. A job exposure matrix was utilized for exposure evaluation. Exposure to acid mists was positively associated with periodontal attachment loss > 4mm at any time (prevalence ratio, PRadjusted = 2.17), past (PRadjusted = 2.11), and over 6 years of exposure (PRadjusted = 1.77), independently of age, alcohol consumption, and smoking, and these results were limited to workers who did not use dental floss. Exposure to acid mists is a potential risk factor for periodontal attachment loss, and further studies are needed, using longitudinal designs and more accurate exposure measures.<br>Este estudo investigou a hipótese de que a exposição ocupacional a névoas ácidas está associada positivamente à doença periodontal, avaliada através da perda de inserção periodontal. O estudo foi conduzido com 530 trabalhadores do sexo masculino de uma metalúrgica. Os dados foram obtidos por meio de entrevistas individuais e de exames clínicos odontológicos. A perda de inserção periodontal foi avaliada durante a sondagem e definida em > 4mm, em pelo menos um dente. Uma matriz de exposição ocupacional foi utilizada para avaliação da exposição. A exposição a névoas ácidas foi associada positivamente à perda de inserção periodontal > 4mm para a ocorrência da exposição em algum momento (RPajustada = 2,17), exposição passada (RPajustada = 2,11) e duração da exposição maior que seis anos (RPajustada = 1,77), independentemente da idade, consumo de álcool e tabagismo; estes resultados foram observados apenas entre os trabalhadores que não usavam o fio dental. A exposição a névoas ácidas é um fator de risco potencial para a perda de inserção periodontal e são necessários outros estudos que utilizem desenhos longitudinais e medidas de exposição mais acuradas