The effect of the surface morphology of Ti-implants on the proliferation activity of fibroblasts and osteoblasts

It is known that surface morphology greatly influences the osseointegration of dental implants. The goal of the experiments conducted by the authors was to study in vitro the effect of various surface modifications on the activity of bone and connective tissue cells. In the experiments they introduced NIH3T3 fibroblast and MCH3T3 osteoblast cells were cultured the surface of ten titanium disks with various morphology in 24-multiwell plates. The cells were let grow on the surface of the disks for two days in a culture medium. One group of the disks underwent scanning electronmicroscopy and the changes in the number and form of cells on the surfaces were studied under various magnifications. From the surface of the second group the cells were lysed and were counted in a Bürker's chamber. After counting the cells they were lysed in a lysis buffer and their protein concentrations were measured with the help of a spectrophotometer. The authors found that only a morphological study of the cells is possible under SEM, they could not detect a quantitative difference in the number or activity of the cells. Upon counting the cells and determining their protein concentration the best result were yielded by the surface roughened by aluminium oxide. In growing fibroblasts the titanium oxide treated surfaces provided good results, while in the case of the osteoblasts the laser treated disks were more successful.     

Potentiation of the bactericidal activity of Harungana madagascariensis Lam. ex Poir. (Hypericaceae) leaf extract against oral bacteria using poly (D, L-lactide-co-glycolide) nanoparticles: in vitro study

Harungana madagascariensis Lam. ex Poir. (Hypericaceae) is known to have biological properties with mainly antibacterial, antifungal, and antiviral effects. The objective of this study was to investigate the in vitro bactericidal activity of the ethyl acetate H. madagascariensis leaf extract (HLE) on the main oral bacterial strains largely implicated in dental caries and gingivitis infections, and the possibility of potentialization of HLE antibacterial effects using the poly (D,L-lactide-co-glycolide) nanoparticles (PLG-NP). The microdilution technique and the interfacial polymer deposition following the solvent diffusion method were used to investigate the in vitro bactericidal activity of ethyl acetate HLE and to prepare nanoparticles, respectively. HLE showed significant bactericidal effects against the bacterial strains tested, with minimal bactericidal concentration (MBC) to 5 x 10(2) mg/l or less, except for Lactobacillus casei with 7.5 x 10(2) mg/l. With the HLE incorporated into PLG nanoparticles (HLE-PLG-NP), we observed diminution of the bactericidal concentration compared to HLE, the upper MBC being of 1.875 x 10(2) mg/l. Incorporation of the HLE into a colloidal carrier optimized its antibacterial performance.     

Oral squamous cell carcinoma: review of prognostic and predictive factors

Oral squamous cell carcinoma has a remarkable incidence worldwide and a fairly onerous prognosis, encouraging further research on factors that might modify disease outcome. In this review article, the authors approach the factors that may exert influence on the prognosis and eventually guide the selection of patients for more aggressive therapies. Published scientific data was collected, selected, and grouped into 3 main clusters: patient-, tumor-, and treatment-related factors. Well established aspects are discussed, but also those less common or with only supposed usefulness. Disease staging, extracapsular dissemination, resection margin free of disease, and tumor thickness are factors with high influence on the prognosis. There has been an increasing interest in the study of tumor molecular factors, and some have been strongly correlated with the outcome, showing promising pathways for the future development of more effective prognosis systems and anticancer therapies.     

牙列重度磨耗对面高度的影响

目的 探讨重度磨耗对面高度的影响。方法 用Willis（威利斯）垂直测量尺测量牙列重度磨耗患者和正常对照组面中高，姿势位面下1／3高度（垂直距离），牙尖交错位面下1／3高度。结果牙列重度磨耗患者垂直距离显著低于对照组（P〈0.05）；而面中高及息止盼间隙与对照组之间未见显著性差异（P〉0．05）；磨耗组面中份高度与垂直距离间有显著性差异（P〈0．001）；而对照组面中高与垂直距离之间差异无统计学意义（P〉0.05）。结论 牙列重度磨耗可导致垂直距离降低但息止耠间隙并未增大。     

Clinical evaluation of a nanofilled composite in posterior teeth: 12-month results

This study compared the clinical performance of a nanofilled resin composite for posterior restorations with 2 microhybrid and 1 packable composite after 12 months of clinical service. Forty-two patients with at least 5 Class I or II restorations under occlusion were enrolled in this study. A total of 148 restorations were placed, 25% for each material (Filtek Supreme, Pyramid, Esthet-X or Tetric Ceram). Two calibrated operators placed all restorations, according to the manufacturers' instructions. One week later, the restorations were finished/polished. Two independent examiners evaluated the restorations at baseline and after 12 months according to the USPHS modified criteria. All patients attended the 12-month recall and 148 restorations were evaluated. Friedman repeated measures analysis of variance by rank and Wilcoxon sign-ranked test for pair-wise comparison was used for data analysis (alpha=0.05). All materials showed only minor modifications, and no differences were detected between their performance at baseline and after 12 months. After 1 year, the nanofilled resin composite showed similar performance to the other packable and microhybrid resin composites.     

手术显微镜在牙髓病治疗中的应用

20世纪80年代以来手术显微镜被应用于牙髓病治疗之中。其完美的视野、极佳的照明和舒适的操作姿势，使得越来越多的口腔科医生认识到其在牙髓病学的诊治、教学、科研中的巨大前景。本文综述了手术显微镜在口腔内科疾病治疗中的实践经验。     

Nonsurgical endodontic management using MTA for perforative defect of internal root resorption: report of a long term follow-up

Internal root resorption is an uncommon lesion following a dental injury. The use of mineral trioxide aggregate (MTA) is a conservative approach to repair lesions with periodontal communication. This case report presents a long-term follow-up of a nonsurgical endodontic management using MTA for perforative defect of internal root resorption. During the endodontic treatment, the granulation tissue was removed and the root canal prepared. Calcium hydroxide was placed as a temporary dressing for 30 days. After this period, the root canal space and the perforation defect were filled with MTA. The clinical findings and periapical radiographs indicated success of treatment until 2 years of follow-up. However, the radiograph after 8 years showed an extensive radiolucent area in the middle third of the root with separation of the apical and coronal root segments. These findings were observed more accurately by using cone-beam computerized tomography.     

Bone density around titanium implants may be influenced by intermittent cigarette smoke inhalation: a histometric study in rats

PURPOSE: This study investigated the influence of cigarette smoke on bone healing around titanium implants placed in rats. MATERIALS AND METHODS: After administration of anesthesia, the tibia surface was exposed and screw-shaped titanium implants (4.0 mm in length and 2.2 mm in diameter) were placed bilaterally (1 each side). The animals (n = 32) were randomly assigned to either group 1 (control, n = 18) or group 2 (intermittent cigarette smoke inhalation, n = 14). After 60 days, the animals were sacrificed and undecalcified sections obtained. Bone density (the proportion of mineralized bone in a 500-microm-wide zone lateral to the implant) was measured in the cortical (zone A) and cancellous bone (zone B) areas. RESULTS: In zone A, a slight difference in bone density was noted between the groups (96.18% +/- 1.08% and 95.38 +/- 1.17% in groups 1 and 2, respectively; P > .05) but was not statistically significant. In contrast, bone density was significantly decreased in zone B in the animals that were exposed to cigarette smoke (17.57 +/- 6.45% and 11.30 +/- 6.81% for groups 1 and 2, respectively; P < .05). DISCUSSION: Whether different results would be observed if animals were exposed to cigarette smoke for a longer period of time and/or before implant placement remains to be investigated. CONCLUSION: Although intermittent cigarette smoke exposure may not seriously affect cortical bone density, it may jeopardize bone quality around titanium implants in the cancellous bone area.