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991.
As part of the Mosgiel Community Study, a longitudinal investigation of the health of the elderly, a dental survey was used to determine the oral health status and treatment needs, both objective and subjective, of a group of dentate older adults. Sixteen percent of the 817 subjects were dentate. Of these, 95 were available for the dental survey, and they were questioned and examined at their homes. The mean age was 77 years, and 55 percent of subjects were male; disproportionately more older males than females had retained some of their natural teeth. Seventy-two percent regularly sought dental treatment, and 39 percent felt they were in need of treatment. Few real barriers to treatment were identified, although a major obstacle preventing many from seeking treatment was their lack of perceived need. However, even the realisation that they required treatment was not sufficient cause for many to seek treatment. All subjects required some form of dental treatment. Eighty-five of the 95 subjects required at least one restoration, and 16 percent advanced restorative treatment. The frequencies of coronal and root surface caries were similar. Oral mucosal pathology was also common. Sixty-five percent of denture wearers required prosthetic treatment. Most subjects needed simple periodontal treatment, but 11 percent required advanced therapy. The main oral health problems of this group related to the simple management of plaque-related disease, and the wearing of dentures. However, 24 percent of people required complex restorative and periodontal treatment, or both.  相似文献   
992.
The three-dimensional orientation of a maxillary cast mounting from a simulated-kinematic facebow transfer was evaluated in multiple trials among three operators on a single subject. The anterior and posterior anatomic facial reference points were marked on the subject. Each operator performed a separate series of trials to reset the anterior facebow component, the two posterior facebow components, and a control series with no resetting of any facebow components relative to the subject. The x, y, and z coordinates of three reference points on the maxillary cast were determined with a machinist microscope relative to a fixed reference after each facebow transfer. A range of differences between mountings of the maxillary cast were found between trials with all three methods used. These mounting errors were due to setting of the instrument and would be expected in routine clinical use of this instrument.  相似文献   
993.
A case of unusual dental findings associated with mild growth and mental retardation is presented. The patient, a 15-year-old girl, manifests small teeth with peculiar short bulbous roots and roundly widened root canals, congenital absence of permanent teeth, strabismus, short stature, and borderline mentality.  相似文献   
994.
summary The influence of a three-layered flexible coating of Polyactive® on bone stress distribution was investigated by three-dimensional finite element models of mandibular bone, in which a titanium implant (coated or uncoated) was located. Poly-active® is a system of poly(ethylene oxide) poly(butylene terephthalate) segmented co-polymers with bone-bonding capacity. In the case of sagittal and transversal loading, the use of a Polyactive® coating reduced both the minimum principal stress in the bone and the compressive radial stress at the bone-implant interface. However, it raised the maximum principal and the tensile radial stress. In the case of vertical loading, the application of a flexible coating reduced the compressive radial stress at the bone-implant interface around the neck of the implant by a factor of 6.6 and the tensile radial stress by a factor of 3.6. Variations in composition and thickness of the coating did not affect the results significantly.  相似文献   
995.
996.
This study was designed to evaluate the use of salivary cotinine, salivary thiocyanate, and expired-air carbon monoxide as biochemical validation measures for assessing the smoking status of adults. The participants were 20 known non-smokers plus 216 admitted smokers and 102 proclaimed quitters participating in a clinical trial of approaches to facilitate smoking cessation. Conventional analytical procedures were utilized. By use of data from known non-smokers and admitted smokers, the sensitivity and specificity of the validation measures were as follows: salivary cotinine, 99% and 100%; expired-air carbon monoxide, 96% and 100%; and salivary thiocyanate, 67% and 95%, respectively. The salivary cotinine and expired-air carbon monoxide tests confirmed smoking cessation for 55% and 74%, respectively, of the proclaimed quitters. The length of time since quitting was significantly related to the results observed with the latter measures. Consideration of these observations along with various practical factors suggests that expired-air carbon monoxide assays may be the validation measure of choice for most clinical trials.  相似文献   
997.
998.
The effect of professional prophylaxis on the periodontium was studied in 14 adolescent orthodontic patients while under active treatment using a split-mouth experimental design. A full-banded appliance was used on all of the patients. The following variables were examined: plaque registration, gingival index, gingival migration, and width of the attached gingiva. Professional rubber-cup prophylaxis was performed on the test side of all patients together with reinforced oral hygiene instruction on a monthly basis. Measurements for the plaque registration, gingival index, gingival migration, and the width of the attached gingiva were recorded at the initial visit (baseline records), the 6-month evaluation, and the 10-month evaluation. Monthly registrations were completed for the plaque deposits and gingival inflammation at each of the 11 visits. All measurements were taken at the midfacial surface of the selected teeth. Four conclusions can be drawn from the findings of this study: the presence of an orthodontic appliance did not result in an increase of plaque accumulation or gingival inflammation for the full-banded orthodontic patient; monthly oral hygiene instruction was effective in significantly reducing the amount of visible plaque and gingival inflammation; monthly rubber-cup prophylaxis had a significant effect in reducing the gingival enlargement routinely associated with a fixed orthodontic appliance; and the width of attached gingiva showed no significant change throughout the course of the study.  相似文献   
999.
1000.
Moral reasoning in dental hygiene students   总被引:1,自引:0,他引:1  
Sixty-five students participated in a study designed to identify the level of moral reasoning of dental hygiene students. Comparisons were made with typical college students and a normative group composed of individuals representing a cross-section of ages and educational levels. The relationships among level of moral reasoning and clinical performance, other selected academic measures, and cognitive style were also assessed. The results indicated that post-certificate dental hygiene students reasoned about moral dilemmas at a higher level than the normative group and at the same level as the college student group. In addition, clinical performance, National Board Dental Hygiene Examination scores, Dental Hygiene Aptitude Test (reading scores), high school rank, and cognitive style correlated positively with level of moral reasoning and specific stages of moral development for postcertificate students.  相似文献   
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