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71.
PURPOSE: An undetermined number of patients with temporomandibular joint (TMJ) symptoms have been treated with intra-articular disc implants composed of Teflon ethylene/propylene or Teflon polytetrafluoroethylene and aluminum oxide (Proplast-Teflon; Vitek, Houston, TX). These implants have shown the potential to fragment in situ resulting in nonbiodegradable particles that stimulate a giant cell reaction and lead to degeneration of local structures, pain, and limitation of mandibular opening. We examined the possible relationship between TMJ implants and persistent pain, responses to sensory stimuli, quality of life, and systemic immune dysfunction. PATIENTS AND METHODS: This case series (32 patients) were referred from university-based orofacial pain centers and private practices from across the United States. Laboratory and clinical assessments evaluated orofacial pain symptoms, neurologic function, clinical signs and symptoms of rheumatologic disease, physical function, systemic measures of immune function, and behavioral measures. RESULTS: We found that TMJ implant patients appeared to have altered sensitivity to sensory stimuli, a higher number of tender points with a diagnosis of fibromyalgia, increased self-report of chemical sensitivity, higher psychologic distress and significantly lower functional ability. Systemic illness or autoimmune disease was not evident in this series of TMJ implant patients. CONCLUSIONS: Significant problems were noted on clinical assessment of TMJ implant patients. This is a US government work. There are no restrictions on its use.  相似文献   
72.
A study was conducted to investigate the influence of temperature and relative humidity (RH) on the bond strengths of several recently developed dentin bonding systems. Six environmental conditions, (A) 25+/-0.5 degrees C, 50+/-5% RH, (B) 25+/-0.5 degrees C, 80+/-5% RH, (C) 25+/-0.5 degrees C, 95+/-5 % RH, (D) 37+/-0.5 degrees C, 50 +/-5 % RH, (E) 37+/-0.5 degrees C, 80+/-5% RH, (F) 37+/-0.5 degrees C, 95+/-5 % RH were used. Bovine mandibular incisors were mounted in self-curing resin and the facial surfaces were ground on wet #600 SiC paper to expose the dentin. After the tooth surface had been treated according to each manufacturer's instructions, adhesives were applied, followed by condensation of resin composites into a mold placed on the dentin surface. Fifteen specimens per group were stored in distilled water at 37 degrees C for 24 h, and then shear-tested at a cross-head speed of 1.0 mm/min. Statistical analysis was carried out with two-way ANOVA followed by Tukey's test (P<0.05). Dentin bond strengths decreased with increasing relative humidity but were not influenced by environmental temperature. Even though one-bottle adhesive systems require a wet dentin surface, their bond strengths are affected by an increase in environmental humidity.  相似文献   
73.
OBJECTIVE: To explore the relationship between the spinability of stimulated whole saliva and periodontal disease progression over 12 months in an elderly population. METHODS: Three hundred and thirty-two subjects aged 76 years at baseline were studied. Attachment loss was calculated on a site-by-site basis, and periodontal disease progression was defined as an attachment loss of >/=3mm. Stimulated whole saliva was collected and salivary spinability (SS) was measured. A multiple linear regression analysis was performed to assess the relationship between periodontal disease progression and SS after controlling for other covariates. The independent variables were selected from those which had significant relationships with disease progression in the bivariate analyses. RESULTS: Mean SS was 1.94+/-0.42mm in males and 1.88+/-0.32mm in females; this difference was not significant. Simple linear regression analysis showed a significant positive relationship between periodontal disease progression and SS (P=0.026), whereas there was no significant relationship between periodontal disease progression and salivary flow rate. Multiple regression analysis revealed a significant positive relationship between periodontal disease progression and SS (P=0.024) after controlling for the number of remaining teeth and baseline periodontal conditions. The model explained 15.5% of the variance in the percentage of sites where the disease had progressed. CONCLUSIONS: These findings suggest that elderly subjects with viscous saliva are prone to periodontal disease progression.  相似文献   
74.
75.
A case of periodontitis in a young adolescent Japanese girl with Down's syndrome is presented in this report. The patient received a monthly preventive course of dental care consisting of mechanical plaque control and oral hygiene instruction. After 2.5 years she recovered from progression of periodontal disease both clinically and microbiologically. The importance of clinical care for periodontitis in Down's syndrome patients is discussed.  相似文献   
76.
Performance of Five Commercially Available Tooth Color-Measuring Devices   总被引:3,自引:0,他引:3  
PURPOSE: Visual tooth color assessment is neither accurate nor precise due to various subjective and objective factors. As newly developed tooth color-measuring devices for dental application provide the possibility of a more objective means of color determination, their performances in vitro and in vivo must be evaluated. The objective of this study was to evaluate the accuracy and precision of five commercially available tooth color-measuring devices in standardized and in clinical environments. MATERIALS AND METHODS: In an in vitro study, standards (A1, A2, A3, A3.5, and A4 shade tabs of Vita Lumin) were measured five times with five electronic devices (ShadeScan, Easyshade, Ikam, IdentaColor II, and ShadeEye) by two operators. In an in vivo study, the right upper central incisors of 25 dental students were measured with the same electronic devices by a single operator. Vita shade tab codes were expressed as CIE (International Commission on Illumination) L*a*b* values and in terms of the precision and accuracy of DeltaE color differences. The Mann-Whitney statistical test was used to analyze the differences between the two operators in the in vitro study, and the Kruskal-Wallis one-way analysis of variance on ranks with the post-hoc Tukey test was used to analyze the accuracy and precision of electronic devices. RESULTS: No statistically significant difference was found between the different operators in the in vitro study. The obtained precision was Easyshade > ShadeScan approximately equal Ikam > IdentaColor II > ShadeEye. The obtained accuracy was Easyshade > ShadeScan approximately equal Ikam > ShadeEye > IdentaColor II. In the in vivo study, the Easyshade and the Ikam were the most precise, and the ShadeEye and the IdentaColor II were more precise than the ShadeScan. With respect to accuracy, there was no statistical difference between the ShadeScan, Ikam, and the Easyshade. The IdentaColor II was considered inaccurate (DeltaE(a)= 3.4). CONCLUSIONS: In the clinical setting, the Easyshade and Ikam systems were the most reliable. The other devices tested were more reliable in vitro than in vivo.  相似文献   
77.
An intraosseous adenoid eystic carcinoma occurring within the body of the mandible of a 47-year-old man is described. A radical en bloc Commando's operation was performed. A five-year follow-up showed no local recurrence or distant metastasis.  相似文献   
78.
ABSTRACT

Objective: A group of patients with recurrent parotitis had clinical symptoms suggesting an obstruction of the glandular duct system, though without any signs of sialoliths or other ductal pathologies.

Methods: Clinical and radiological data of five patients with recurrent obstructive parotitis and long-standing definite bruxism were reviewed retrospectively. Ultrasonography, MRI, and sialendoscopy were performed for evaluation of ductal pathologies as the cause of glandular obstruction. Electromyography was used to evaluate the activity of masticatory muscles in all patients. The parotitis was treated with injection of botulinum toxin into the buccinator muscle.

Results: Dilatation of the Stensen’s duct proximal to the area of the buccinator muscle was shown in radiological examination with no evidence of ductal strictures. Electromyography revealed an abnormal activity of the ipsilateral buccinator muscle. All patients were free of disease after treatment of the buccinator muscle.

Discussion: Bruxism should be considered as a possible cause of recurrent parotitis.  相似文献   
79.
ABSTRACT

Objective

The aim of this study was to evaluate the effect of an occlusal splint on body posture of intra-articular temporomandibular joint (TMJ) disorders patients.  相似文献   
80.
The effect of age on the strength of self-curing acrylic resin repairs has been investigated. Several other properties which may be related were also studied. The findings indicate that the strength of a repair increases with time, attaining a significant proportion of its final strength by 24 hours and reaching a maximum between 1 day and 1 week.  相似文献   
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