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61.
Objective. The aim of this study was to determine the feasibility of a novel saliva-activated bioadhesive drug delivery system of lidocaine hydrochloride as a viable alternative to infiltration anesthesia in dentistry.Study design. The study was carried out in three stages. First, the drug delivery system (DDS) was subjectively evaluated for adherence to the gingival mucosa and peak effect of anesthesia. In the second stage, a comparative subjective and objective evaluation of the DDS with a marketed topical gel preparation was carried out. Finally an open label, nonblinded clinical trial was carried out using the exodontia model. A total of 49 extractions were attempted in 41 patients. The effect of the following variables was investigated in the study: (1) jaw (maxillary and mandibular), (2) overall mobility, (3) position-notation of tooth (1, 2, 3, 4…). The positive extractions were statistically analyzed by the t test comparison of means of two independent variables.Results. Subjective evaluation revealed that the DDS adheres to the gingiva within a minute and produces peak effect in 15 minutes. Comparative study revealed that the DDS produces greater depth of anesthesia than the marketed topical gel. Of 49 extractions attempted with the DDS, 40 were successful, giving an efficacy of 81.63%.Conclusion. The novel saliva-activated bioadhesive drug delivery system of lidocaine hydrochloride exhibits potential as a feasible alternative to infiltration anesthesia in dentistry.  相似文献   
62.
Exfoliative cytology is a rapid, non-invasive procedure for assessing dysplastic change within the oral epithelium. The indications for oral exfoliative cytology are reviewed and a technique for cell collection and smear examination is presented. The value of exfoliative cytology in oral cancer screening programmes as a public health measure is discussed.  相似文献   
63.
Preventive Behaviors as Correlates of Periodontal Health Status   总被引:1,自引:0,他引:1  
Objectives: This investigation examined current practices of brushing, flossing, and periodic dental visits and their association with periodontal health status. Methods : Data were collected using face-to-face interviews and 40-minute in-home dental examinations with a probability sample of adults 18 years of age or older, having at least one tooth, and living in housing units in the Detroit tricounty area. Complete examinations were performed on 319 individuals. Results : On average, subjects reported brushing their teeth about twice a day. About one-third of the population reported flossing at least once a day. Loss of periodontal attachment was related to frequency of brushing while subjects who exhibited acceptable flossing ability had less plaque and calculus, shallower pocket depths, and less attachment loss. Subjects reporting a periodic dental visit at least once a year had less plaque, gingivitis, and calculus than subjects reporting less frequent visits. In regression analyses, brushing thoroughness, flossing ability and frequency, and dental visit frequency were predictors of lower plaque, gingivitis, and calculus scores. In turn, these scores were predictors of shallower pocket depths and less attachment loss. Conclusions : Brushing, flossing, and periodic dental visits were correlated with better periodontal health. The behaviors appeared to be indirectly related to pocket depth and attachment loss through their associations with plaque, gingivitis, and calculus levels.  相似文献   
64.
Forty cervical abrasion lesions were restored with a self-cure Type 2A glass ionomer cement. Prior to placement of the restorations, 20 lesions were scrubbed for 15 seconds with 25 per cent polyacrylic acid and 20 lesions were cleaned with a pumice and water slurry on a rubber cup. After three years, there was negligible marginal staining, and one restoration from each group was partly lost. There was no evidence to suggest that polyacrylic acid was preferred to pumice and water in the restoration of cervical abrasion lesions with glass ionomer cement.  相似文献   
65.
In HIV infected patients, a distinct form of gingivitis and periodontitis was reported recently. This paper reviews the clinical and microbiological features of these lesions and makes recommendations regarding their clinical management. The need for early treatment and control of periodontitis in HIV seropositive patients is emphasized.  相似文献   
66.
Comparisons of physical features within identical (monozygous) and non-identical (dizygous) twin pairs have provided valuable insights into the relative contributions of genetic and environmental influences to observed variability. The special nature of the twinning process itself also provides an opportunity to learn more about early human development, including how body symmetry is determined. The mechanisms of twinning, mortality and morbidity in twins, determination of body symmetry including the phenomenon of mirror-imaging, postnatal growth and development of twins, and zygosity determination are discussed. Twin studies with direct relevance to clinical dentistry are reviewed and illustrated by examples from an ongoing investigation of dentofacial morphology in South Australian twins.  相似文献   
67.
Australians may receive free dental treatment via the public sector if they have a health care card but otherwise must seek treatment via the private sector. These two modes of dental delivery have different objectives, facilities, and patient populations. Two groups of patients, one public and one private, who presented to the same clinicians with temporomandibular joint dysfunction were studied. There were differences in age, numbers of natural teeth and some psychological features. However, the outcome to simple non-surgical management resulted in similar levels of successful treatment.  相似文献   
68.
Since 1975, more than 100,000 Indo-Chinese refugees from Vietnam, Kampuchea, and Laos have been resettled in Australia. This dental survey was undertaken to compare the dental health of 104 Australian-born and 126 Indo-Chinese adolescents from a State high school within a high migrant area of Melbourne. The mean DMFT score for the Australian-born group was 3.37 teeth, compared with 6.05 for the Vietnamese group, and 3.10 for the Kampuchean-Laotian group. More restorations and extractions were required by the Vietnamese subjects compared with the Australian-born and Kampuchean-Laotian subjects. Almost all subjects had gingivitis, however the proportion of Indo-Chinese subjects with shallow and deep pockets was greater than that of the Australian-born subjects. The periodontal health of the Kampucheans and Laotians was the most severe of the Indo-Chinese groups. These findings indicate that the Indo-Chinese adolescent refugees represent a high risk group for dental problems within the Australian population.  相似文献   
69.
The history of denture base materials and the accompanying development of impression techniques are traced from the earliest times to the present day (Part 1) as a prelude to a study (Part 2–4) of the various theories that have been advanced to explain retention of the base without mechanical support. These theories are critically reviewed and tabulated in chronological order. Some areas for further investigation are identified.  相似文献   
70.
The original design of a semi-precision extra-coronal attachment for partial dentures is illustrated, and its fabrication in a cast non-precious bondable alloy is described. A step-by-step method is also described of bonding multiple attachments in parallel for the retention and support of removable partial dentures. Clinical cases are illustrated. The results of trials indicate that the method is clinically viable and, in selected cases, appears to offer distinct advantages over existing retention systems.  相似文献   
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