Evaluation of mandibular range of motion in Brazilian children and its correlation to age, height, weight, and gender

This study aimed to measure the active mandibular range of motion (ROM) (mouth opening: MO; right and left lateral movements: RL and LL; protrusion: P) in Brazilian children of both genders and of various ages, weights, and heights, and to establish correlations among such variables. Study subjects (n = 303) were healthy boys and girls, with ages ranging between 6 and 14 years, who were regular students of a public school in the state of S?o Paulo. Analysis of variance and intra-class correlation coefficients were considered significant for p < 0.05. Weak significant correlations were observed between mandibular ROM and age, height, and weight. No statistically significant differences (p > 0.05) were observed regarding mandibular ROM between gender groups. Mean mandibular ROM values showed significant increases (p < 0.05) in relation to age, height, and weight, except for RL (p > 0.05), in the studied age range. Significantly smaller (p < 0.05) mean mandibular ROM values were observed for the intervals of 6 and 7 years of age, 1.15-1.35 m, and 17.30-26.50 kg, in relation to the other ranges. Nonetheless, no differences were observed among mean mandibular ROM values in the ranges 8 to 12-14 years, 1.36-1.75 m, and 47-85 kg. Thus, it is suggested that weight, height, and age variables be considered when obtaining mandibular ROM values, particularly in children aged 6 to 7 years, measuring 1.15-1.35 m, and weighing between 17.3-46.5 kg.     

The application of microscopic surgery in dentistry

The use of the microscope as a tool for practising Medicine, especially in surgical specialisations, has been established for decades. The microscope was first used in OdontologyDentistry back to the 1970s and 1980s, and was introduced more widely (although it was still far from being in general use) during 1990s. The purpose of this article is to describe the main applications of the microscope in OdontologyDentistry today, as well as providing odontologists and stomatologists, whether specialists or in general practice, with information about microscopic OdontologyDentistry for better patient care. This work also gives particular importance to matters needed to achieve the necessary manual dexterity to work in a magnified operating field using a surgical microscope (SM).     

CDIC柱状种植体周龈下菌群变化的2年观察

目的：了解种植体周龈下菌群构成变化与种植体周围组织炎的关系，方法：观察64枚CDIC种植体植入术后2年内种植体周龈下细菌构成变化以及相关临床指标。结果：种植体植入术后1月、3月、6月的龈下球菌比值降低。螺旋体，梭形菌比值增高，杆菌，弯曲菌比值差异无显著性意义。术后12月，24月这五类菌的比值接近术前水平，临床菌斑指数，龈沟出血指数高者，种植体周龈下细菌中球菌的比值较低，梭形菌，螺旋体的比值较高。结论：早期进行口腔卫生指导和定期细菌学检测，对提高种植义齿成功很有必要。     

Mechanical properties of visible light-cured resins reinforced with hydroxyapatite for dental restoration.

OBJECTIVES: The purpose of this study was to measure and analyze the mechanical properties of several composite materials designed for dental restoration. METHODS: The materials were composed of a visible light-curing monomer mixture (either Bis-GMA+TEGDMA or Bis-GMA+HEMA) as a matrix and hydroxyapatite (either microscopic or nanoscopic particles) as a reinforcing filler. The surface of the hydroxyapatite particles was modified by using a coupling agent (citric, malic, acrylic or methacrylic acid). Five specimens of 14 different composites were prepared for each mechanical test: flexural strength, Young's modulus and Vickers hardness. Mean values and standard deviations were calculated, and ANOVA and Student Newman Keuls multiple comparison tests were applied (P < 0.05). RESULTS: The addition of 50-60 wt% of hydroxyapatite particles to the unfilled monomer mixtures led to the increase of both Young's modulus and surface hardness of the material, while the flexural strength decreased. In general, when microscopic instead of nanoscopic hydroxyapatite was used as a reinforcing filler, mechanical properties were favored. The mechanical properties were also improved by adding citric, acrylic or methacrylic acid as a coupling agent. CONCLUSIONS: An adequate surface modification of the hydroxyapatite particles conferred enhanced mechanical properties to the final dental composite. Microscopic-hydroxyapatite particles are preferred to nanoscopic ones.     

影响老年心血管病患者开髓治疗危险性的多因素分析

目的探讨老年心血管疾病患者开髓治疗过程中的潜在危险性及影响因素。方法对235例老年心血管疾病患者心电监护下开髓治疗的资料，按治疗时心率和血压的波动、心电图缺血性改变、心律失常的发生或加剧作为潜在的危险因素(y1～y5)及患者的年龄、性别、心血管病的种类、心功能、治疗时精神状态、麻醉效果6个自变量(x1～)x6)，应用电子计算机行多元逐步回归及logistic回归分析。结果老年心血在管疾病患者开髓治疗时潜在危险的影响因素依次为：治疗时精神紧张、麻醉效果差、心脏病种类、心功能、年龄、性别。结论通过对老年心血管疾病患者开髓治疗时潜在危险性影响因素的分析，指导临床采取有效的安全措施。