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61.
A study was conducted to determine the effectiveness of several commercial pastes in polishing the surfaces of composite resin material. Five samples of Concise composite resin contained within Plexiglas block holders were prepared using Mylar matrices. One block was disked only; three blocks were disked and polished, each with a different paste. The remaining block was the control. The surface roughness of all samples was measured with a stylus profile instrument. Five extracted teeth were prepared in the same manner with Concise composite resin and Mylar strip matrix. In each tooth, the surface was finished by disking only or by disking followed by polishing with one of three pastes. The fifth tooth was the control. The samples were examined by use of a scanning electron microscope. Quantitative evaluation of over-all computer data indicated that the smoothest surface was found immediately ater removal of the Mylar matrix and that pastes leave a rougher surface than is left with a disc.  相似文献   
62.
63.
Scleroderma, or progressive systemic sclerosis (PSS), an autoimmune rheumatic condition affecting the connective tissues, has a profound impact on oral health. Common orofacial findings include xerostomia, gastroesophageal reflux disease and limited mouth opening. This review article describes scleroderma, or PSS, and its various manifestations. The features of CREST syndrome and morphea are reviewed. Concerns relevant to the prevention of dental disease and the safe delivery of dental care in this group of challenging patients are emphasized.  相似文献   
64.
PURPOSE: To assess the association between risk markers of chronic oral inflammation and changes over time in periodontal probing depth (PD) in the third molar region, the distal of a second molar, or around a third molar. SUBJECTS AND METHODS: The data from these analyses are part of a study of subjects enrolled with 4 asymptomatic third molars with adjacent second molars in an institutional review board-approved longitudinal trial. Full-mouth periodontal probing was conducted at enrollment and follow-up. Enrollment levels of periodontal pathogens and gingival crevicular fluid inflammatory mediators were assayed as indicators of the degree of oral inflammation. Subjects were categorized as those who had at least a 2 mm change in periodontal PD between baseline and follow-up in the third molar region and those who did not. The relationship between aggregated subject baseline PD, levels of periodontal pathogens, and gingival crevicular fluid IL-1 beta, and the proportion of subjects with changes in PD >or=2 mm versus those with PD <2 mm were compared with Cochran-Mantel-Haenzsel statistics. Level of significance was set at 0.05. Risk assessment models for a change in PD >or=2 mm were developed using logistic regression analysis. RESULTS: Twenty-four percent of 254 subjects exhibited a change in PD from baseline to follow-up of >or=2 mm in the third molar region. Of these, 95% had a baseline PD of >or=4 mm. Both high (>or=10(5)) "orange" and "red" complex bacteria and PD of >or=4 mm detected at enrollment were significantly associated with a change in PD >or=2 mm. Odds of a change in PD >or=2 mm were increased if baseline pathogen levels were >or=10(5) or a PD of >or=4 mm was detected at enrollment. CONCLUSION: Our findings are consistent with chronic oral inflammation leading to a progression of periodontal disease in the third molar region.  相似文献   
65.
Lichen planus is a dermatologic disease of unknown etiology characterized by keratotic plaques on the skin. Many patients also harbor white lesions of the oral mucosa. The literature contains numerous reports of lichen planus-like lesions evolving in conjunction with the administration of a variety of pharmacologic agents. It is difficult, if not impossible, to distinguish such lesions from one another. The present study evaluated the epithelial and basement membrane thickness, mast cells (intact cells and degranulated cells subepithelially) and the presence or absence of blood vessels in oral lichen planus and oral lichenoid lesions. The evaluation was done using the periodic acid-schiff (PAS) and toluidine blue staining techniques on 20 cases each of oral lichen planus and oral lichenoid lesions and 5 control specimens of normal buccal mucosa. The results showed an increased number of degranulated mast cells in areas of basement membrane degeneration, increased vascularity and increased PAS-positive basement membrane thickness in oral lichen planus as compared with oral lichenoid lesions. Reduced epithelial thickness was found in oral lichen planus. The present study emphasizes the importance of these parameters in differentiating oral lichen planus from oral lichenoid lesions using special staining techniques.  相似文献   
66.
67.
BACKGROUND: The aim of this clinical study was to compare the results of non-surgical treatment of periodontal disease with an erbium-doped:yttrium, aluminum, and garnet (Er:YAG) laser to root debridement with an ultrasonic scaler. METHODS: Twenty-five patients furnished two quadrants containing four teeth with probing depths (PD) >4 mm; the quadrants were divided equally between the right and left sides. On one side, teeth were treated by Er:YAG laser using 160 mJ/pulse at 10 Hz (test group); on the contralateral side, teeth were treated by ultrasonic scaler (control group). Clinical baseline data, including plaque index, gingival index, probing depth (PD), and clinical attachment level (CAL), were recorded before treatment and at 3 months and 1 and 2 years. RESULTS: There were statistically significant differences in PD between the test and control groups for pockets of 1 to 4 mm (P <0.05), 5 to 6 mm (P <0.01), and > or =7 mm (P <0.001). However, there were no significant differences between the test and control groups for CAL gain in pockets of 1 to 4 mm; statistically significant differences were found between the test and control groups in pockets of 5 to 6 mm (P <0.01) and > or =7 mm (P <0.001). CONCLUSION: Er:YAG laser periodontal treatment resulted in statistically significant improvements in PD and CAL gain compared to ultrasonic scaler treatment at 2-year follow-up, especially in moderate and deep pockets.  相似文献   
68.
Treatment of peri-implant osseous defects represents a significant challenge for clinicians, and the need to evolve within predictable surgical procedures is important. This case report describes the surgical treatment and grafting with porous titanium granules (PTG) of one patient with a peri-implant osseous defect. The suggested thrombogenic properties of titanium are intriguing from the perspective of osseous reconstructive surgery. In an ongoing randomized clinical trial using PTG for treatment of peri-implant osseous defects, one patient with one test implant was excluded and scheduled for implant removal. The surgical therapy included open flap debridement with surface decontamination with 24% EDTA gel, grafting with PTG, and resubmersion of the implant. After 12 months of healing, the implant with surrounding tissues was excised en bloc and micro CT and histological analyses were performed. Analyses showed PTG in close contact with new bone and with bone growing both into the porosities of the graft material and onto the adjacent implant surface. Element analysis demonstrated calcium and phosphorus in the new tissue embedding the PTG and the implant. Int J Oral Maxillofac Implants 2011;26:e9-e14.  相似文献   
69.
Mycoplasma salivarium in human gingival sulci   总被引:9,自引:0,他引:9  
The prevalence and quantity of mycoplasmata in the gingival sulcus area of periodontally diseased and periodontally healthy subjects was tested. Mycoplasma salivarium was the predominant sulcular species and occurred in a significantly higher percentage of diseased subjects than healthy subjects (p<.0005) (86.7 % vs 31.8 %). When mycoplasmata were present in the sulcus their concentration was usually 106–107 per gram of fluid whereas the concentration in saliva was approximately 100 to 1000 fold less. Therefore M. salivarium appears to be primarily a sulcular organism. M. salivarium may be part of the complex plaque which appears to produce gingivitis.  相似文献   
70.

Objectives

Natural rubber latex (NRL) contains over 200 proteins of which 13 have been identified as allergens and the cause of type I latex allergy. Health care workers share a high occupational risk for developing latex allergy. Filaggrin null mutations increase the risk of type I sensitizations to aeroallergens and it is possible that filaggrin null mutations also increase the risk of latex allergy. The aim of this paper was to examine the association between filaggrin null mutations and type I latex allergy.

Methods

Twenty latex allergic and 24 non-latex allergic dentists and dental assistants, occupationally exposed to latex, were genotyped for filaggrin null mutations R501X and 2282del4. Latex allergy was determined by a positive reaction or a historical positive reaction to a skin prick test with NRL.

Results

41 individuals were successfully genotyped. Three individuals were filaggrin mutation carriers. One (2.4%) was a 2282del4 heterozygote and two (4.9%) were R501X heterozygote. No homozygote or compound heterozygote carriers were detected. No association between filaggrin null mutations and type I latex allergy was found (p = 0.24). Patients with type I latex allergy more often reported contact dermatitis.

Conclusions

This is the first study to examine a highly plausible association between filaggrin null mutations and type I latex allergy. The study subjects were occupationally exposed to latex but no association between latex allergy and filaggrin mutations were detected. Sensitization to latex in the cases in this study may not have occurred through direct skin contact but through the respiratory organs via latex proteins that are absorbed in glove powder and aerosolized.  相似文献   
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