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991.
992.
993.
Concentrations of testosterone, dehydroepiandrosterone, eslradiol, progesterone, 17α-hydroxyprogesterone, and cortisol were measured in the saliva by radioimmunoassay. Saliva from male and cycling and postmenopausal female patients with and without periodontitis was studied.
It was found that salivary concentration of progesterone was increased in all patients with periodontitis. While testosterone was significantly increased in the female diabetic and non-diabetic patients with periodontitis, no difference in its concentration was found in the saliva of non-diabetic males with and without periodontitis. Salivary dehydroepiandrosterone was also increased in postmenopausal females with periodontitis. In contrast, estradiol was significantly decreased or not measurable in all patient groups with periodontitis. The concentration of cortisol and 17α-hydroxyprogesterone showed no significant differences in postmenopausal patients with and without periodontitis. In addition, the salivary concentration of all hormones in postmenopausal females showed circadian variation. Moreover, results obtained in postmenopausal and ovariectomized females provided evidence for extragonadal production of sex steroid hormones in postmenopausal females.
The present results suggest that there is a relationship between the altered production of sex steroid hormones and the incidence of periodontal pathology.  相似文献   
994.
It is important to give the patient a denture that is clean and free from cross-contamination. This study was made to determine if Clorox could be used as a rapid, safe, and clinically effective way to sterilize complete dentures. The data obtained from this study indicate that a 5-minute immersion of dentures in undiluted Clorox accomplished sterilization against a variety of microorganisms, including a spore-forming bacteria and C. albicans.  相似文献   
995.
Two cases of fibrous defect (nonossifying fibroma) of the mandible are presented. Each case occurred in the mandibular ramus of an 11-year-old girl. The usual fibrous defect of bone is an intraosseous fibrous, nonneoplastic, reactive lesion which appears as a well-delineated defect in the metaphysis of long bones. This report reviews the literature, histopathology, and classification of the fibrous defect of bone.  相似文献   
996.
This article describes a method for constructing composite slides without destroying the original slide. A conventional slide projector, rear-projector screen, modified 35 mm camera, and slide-duplicating film are required for this technique.  相似文献   
997.
BACKGROUND: The authors investigated mouthrinses' antimicrobial effectiveness against predominant oral bacteria, as determined by the minimum inhibitory concentration (MIC). Specifically, they evaluated an herbal mouthrinse, an essential oil rinse and a 0.12 percent chlorhexidine gluconate rinse. METHODS: The authors assessed the inhibitory effects of the three test agents against 40 oral bacteria at concentrations of 1, 2, 4, 8, 16, 32, 64, 128, 256 and 512 micrograms per millliter. They inoculated plates containing basal medium and the test agents with suspensions of the test species and incubated them anaerobically at 35 degrees C. The authors interpreted the MIC as the lowest concentration of the agent that completely inhibited the growth of the test species. RESULTS: The herbal mouthrinse inhibited the growth of most of the 40 test species. Compared with the essential oil mouthrinse, the herbal mouthrinse exhibited significantly lower MICs for Actinomyces species, periodontal pathogens Eubacterium nodatum, Tannerella forsythia and Prevotella species, as well as the cariogenic pathogen Streptococcus mutans. The chlorhexidine gluconate rinse had the lowest MICs compared with the essential oil rinse and the herbal rinse for all test species examined. CONCLUSIONS: Although less potent than the chlorhexidine gluconate rinse, the herbal rinse was more effective than the essential oil rinse in inhibiting the growth of oral bacteria in vitro. CLINICAL IMPLICATIONS: The data suggest that the herbal mouthrinse may provide oral health benefits by inhibiting the growth of periodontal and cariogenic pathogens. In vivo clinical testing is essential to confirm in vitro results.  相似文献   
998.
The kinematic center (KC)-defined by coinciding jaw-opening/-closing and protrusion-retrusion trajectories-has been proposed in the literature as a reference point to represent TMJ movements. In this study, we tested whether the KC lies in a peculiar anatomical point and whether its trajectory reflects intra-articular distance. In 11 asymptomatic individuals (seven females, four males, aged 24-37 yrs), 4 openings/closings and 4 protrusions/retrusions were tracked with dynamic stereometry. In a 3D lattice (0.5 mm grid) constructed solidly around each condyle, the KC was the point with maximal cross-correlation between opening-closing and protrusion-retrusion paths. KC trajectories were more cranial on closing than on opening, consistent with intra-articular distances being smaller on closing than on opening. However, KCs were never located on condylar main axes (distance, 4.5 +/- 2.9 mm), nor did they coincide with points best approximating fossa shapes (distance, 12.5 +/- 6.4 mm). The kinematic center's anatomical and functional significance therefore appears to be questionable.  相似文献   
999.

Objective

Antigen I/II of mutans streptococcus (MS) is a surface protein, which binds to salivary receptors. The objective of this study was to study the effect of a peptide corresponding to residues 1025-1044 of antigen I/II and a dentifrice containing peptide on the adherence of MS.

Methods

The peptide was synthesized and included into dentifrice. Anti-adherence experiments of the peptide and a dentifrice containing it were processed in vitro and in vivo.

Results

The results showed that the adherence of MS to hydroxyapatite was inhibited by synthetic antigen I/II peptide and also by a dentifrice containing the peptide in vitro. The numbers of MS in plaque from subjects treated with dentifrices containing the peptide for 1 month was significantly reduced compared to baseline (log 3.11 ± 0.80 vs log 4.09 ± 0.90, P < 0.01), whereas the control group showed no reduction.

Conclusion

The adherence of MS to hydroxyapatite was inhibited by both a synthetic peptide and a dentifrice containing the peptide. The peptide dentifrice produced a significant reduction of MS in dental plaque in vivo.  相似文献   
1000.
AIM: The aim of this study was to compare the clinical and microbiological healing outcomes following non-surgical periodontal therapy using the new Vector ultrasonic system versus scaling and root planing (S/RP) with Gracey curettes. MATERIAL AND METHODS: The study comprised 20 chronic periodontitis patients. Using a split-mouth design, both treatment modalities were randomly applied to one quadrant of the upper and the lower jaws each. Clinical and microbiological parameters were assessed at baseline, 4 weeks, and 6 months after treatment. Furthermore, post-operative hypersensitivity was assessed. The Wilcoxon signed rank test (alpha=0.05) was used for statistical analysis. RESULTS: Both therapies provided statistically significant clinical and microbiological improvements of periodontal conditions after 4 weeks and 6 months. Hypersensitive teeth were found only 4 weeks after S/RP. Besides a significantly better bleeding on probing reduction in deep S/RP sites, no other clinical and microbiological parameters revealed significant differences between the sites treated with the Vector system or S/RP. CONCLUSION: Both the Vector system and S/RP provided favourable periodontal healing results, although in deep pockets S/RP appeared to achieve a better resolution of inflammation.  相似文献   
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