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91.
Transverse molar movements during growth   总被引:1,自引:0,他引:1  
The purpose of this study was to evaluate changes in molar crown torque and intermolar arch width from the time of permanent first molar eruption to early adulthood. Molar crown torque and intermolar arch width were measured in 36 untreated subjects with Class I occlusion from the Iowa Facial Growth Study at approximate ages 7.5, 10.3, 12.9, 16.5, and 26.4 years. On average, the mandibular first and second molars uprighted buccally by 5.0 degrees and 7.5 degrees, respectively. Mandibular first and second molar intermolar width increased by 2.2 and 0.78 mm, respectively. On average, maxillary first and second molars uprighted lingually by 3.3 degrees and 5.9 degrees, respectively. Maxillary first and second intermolar width increased by 2.8 and 2.0 mm, respectively. Results of statistical analysis by the Wilcoxon signed rank test indicate that (1) maxillary molars erupt with buccal crown torque and upright with age, whereas mandibular molars erupt with lingual crown torque and upright with age (P <.01), and (2) molar crown torque changes are accompanied by concurrent increases in maxillary and mandibular intermolar width (P <.01).  相似文献   
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A critical factor that needs to be evaluated during the diagnosis and treatment planning phase for patients seeking an implant-tissue-supported overdenture or metal-resin implant fixed denture is the presence of adequate interarch distance. The amount of interarch distance is critical to the selection of appropriate implant abutments and attachments for both implant-tissue-supported overdentures and metal-resin implant fixed complete dentures. This clinical report describes a patient with complications related to the failure to diagnose inadequate interarch distance, and the methods used to resolve the patient's chief complaint. A guide for abutment-attachment selection using one commercially available implant system is given.  相似文献   
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Objectives—To report our experience with temporalis myofascial flaps (TMF), describe the healing process of uncovered flaps in the mouth, and the histology of the repaired mucosa in the long term. Design—Prospective clinical and histological study. Subjects—36 patients who received a TMF over a 6.5 year period for serial assessment of the oral healing, 24 patients whose scars over the reconstructed area were assessed clinically, and 11 whose repaired mucosa was assessed histologically. Main outcome measures—To follow the clinical process of oral healing of the TMF and describe the repaired mucosa healed over the flap. Results—The uncovered TMF in the mouth healed gradually starting with an acute inflammatory phase, going through chronic inflammatory and proliferative phases with eventual epithelialisation of the oral mucosa. There were no major complications. The healed mucosa showed mild scarring in 70% of cases and the repaired mucosa had characteristic histological features that were distinct from the normal mucosa. Conclusion—The TMF is an extremely reliable and versatile flap for maxillofacial reconstruction which heals gradually with eventual coverage by mildly scarred repaired mucosa.  相似文献   
97.
The University of Sydney Dental School and more recently the Implant Centre have been treating patients with the Brånemark Osseointegration Implant System since 1981. Success depends on close cooperation between surgeon and prosthodontist. This paper describes specific prosthodontic treatment planning procedures based on a general knowledge of prosthodontics, and detailed methods for determining the position, length and alignments of the implants for a specific case by the use of radiographic and surgical templates.  相似文献   
98.
Objectives : This study compares the distributional and psychometric properties of the Geriatric Oral Health Assessment Index (GOHAI) in two samples of older adults, and examines how the self-perceived impact of oral disease, as measured by the GOHAI, varies in accordance with sample sociodemographic and health characteristics. Methods : Results are based on survey data from two samples of older men: a Medicare sample of patients using community physicians (n=799; mean age=74) and users of VA ambulatory health care (n=542; mean age=72). Results : The findings indicated significant differences between samples in mean GOHAI scores, with the VA sample exhibiting worse scores. A number of similarities in psychometric properties of the instrument across the two samples were found: high internal consistency reliability and similar inter-item and item-scale correlations. Factor analyses revealed somewhat different structures between the two samples, but explained similar amounts of variance; regression analyses indicated that income and self-rated oral health were significant predictors of GOHAI scores in both samples. Conclusions : The GOHAI exhibits satisfactory psychometric properties in both samples and is sensitive to sociodemographic differences among and between two samples of older men. Results suggest continued use of the GOHAI as an indicator of the impact of oral conditions on functioning and well-being in a variety of samples.  相似文献   
99.
To be truly useful, an index must be applicable universally without modification. The data presented in this article support the use of the standard DAI without modification to assess need for orthodontic treatment in both developing and industrialized countries. When students from Thailand, Australia, the German Democratic Republic, and Native Americans residing on Indian reservations rated the same 25 occlusal stimuli (photographs of dental configurations) for dental aesthetics, their ratings of these stimuli when arranged in rank order were highly correlated with those of US students. These 25 occlusal stimuli were a subset of the original 200 occlusal stimuli used in deriving the standard DAI regression equation. This article presents data indicating that when a Native American DAI was derived based on Native American ratings of the same 200 occlusal stimuli used in deriving the standard DAI, the Native American DAI and the standard DAI had the same ten components (orthodontic measurements) and strikingly similar regression coefficients (weights). Further analysis indicated that the two equations were sufficiently similar to justify using the standard DAI to obtain DAI scores on Native Americans and to estimate the relative social acceptability of their dental aesthetics. If ratings for dental aesthetics for the full set of 200 stimuli were available for each of the countries where only 25 were rated, we expect that, as in the case of Native Americans, a country-specific DAI, if computed, would be sufficiently similar to the standard DAI that no modification would be needed to allow use of the standard DAI in that country.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
100.
Investigation of the film thicknesses of four luting glass ionomer cements over a range of powder/liquid ratios indicated that the four cements had a similar potential film thickness of approximately 28 μm. Scanning electron-microscopic examination revealed that the glass ionomer cement powders contain a small number of relatively large particles and an abundance of very fine particles.  相似文献   
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