A comparative morphologic study of Carabelli cusp between Chinese and Japanese students.]

The study of teeth,dentition and occlusion is helpful to guide oral medical clinic and the study of anthropology.Our department of Osaka Dental University and had many items of research work about teeth,dentition and occlusion between Chinese and Japanese students.This article reports the study of Carabelli cusp.The results revealed:(1)the rate of Carabelli cusp is higher in Japanese than in Chinese and is higher in male than in female.(2)the rate of Carabelli cusp of the first maxillary molar of both side is very high.(3)The rate of Carabelli cusp is related to the height and the type of cusp numbers.These all illustrated the occurence of Carabeiil cusp were influenced by race, individual and the development of teeth.     

Preventive Behaviors as Correlates of Periodontal Health Status

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.     

Polished versus autoglazed dental porcelain

This study compared the finishes on dental porcelain polished with four different polishing paste systems with oven reglazing and with a porcelain adjustment kit without a polishing paste. The polished/reglazed samples were rated according to quality of finish by independent observers and by scanning electron microscopy. On the basis of visual examination, two of the polishing paste systems tested were found to produce a surface equal to or better than oven glazing. On the basis of SEM examination, oven glazing was found to produce a better surface than the other polishing methods. Not all porcelain polishing systems produce a surface comparable to oven-glazed porcelain, and porcelain polishing systems should be chosen carefully.     

Etidocaine hydrochloride in surgical procedures: effects on postoperative analgesia

Because early research has established the prolonged duration of the effects of etidocaine, this study was performed to determine whether the long-acting local anesthetic can reduce the need for postoperative analgesics after oral surgery.     

Student dental hygienists' and dental hygiene educators' attitudes toward the handicapped

The purpose of this study was to determine the attitudes of student dental hygienists and dental hygiene educators at four educational sites in a north central state in the United States, using the Dental Students' Attitudes Toward the Handicapped Scale (DSATHS) developed by Lee and Sonis. It was hypothesized that (1) the majority of students would express a negative attitude toward the handicapped and (2) no significant differences would be found between students and educators. Of the 110 students surveyed, there was an 84% response rate. Of the 46 educators surveyed, there was a 78% response rate. The data were analyzed using frequency distributions. Chi-square analyses were performed to determine if significant differences exist between (1) student dental hygienists and (2) student dental hygienists and dental hygiene educators. The criterion for statistical significance was p less than .05 for all analyses. The results revealed that over 50% of the students have a positive attitude toward their (1) educational experience; (2) perceptions of their instructors' experiential qualifications in working with the handicapped; and (3) desire for future and interpersonal relationships with the handicapped. However, more students have a positive attitude toward their relationships with the handicapped than toward their educational experience and perceptions of instructors relative to the handicapped. Fewer than 50% of the students agreed that their (1) educational experiences facilitate confidence or enjoyment in working with the handicapped; (2) teachers demonstrated enthusiasm or enjoyment when working with the handicapped; and (3) school's program for treatment of the handicapped is good.(ABSTRACT TRUNCATED AT 250 WORDS)     

Social characteristics and oral health behaviour of families in Riverlea

Planning of community health programmes requires a comprehensive "community diagnosis" as its basis, taking into account a complex range of health related factors. The family and particularly the mother play a crucial role in oral health. Thus, the social context, the source and extent of health information, as well as their oral health behaviour, can determine the mothers' function in promoting oral health. This study examined the social characteristics and oral health behaviour of families in Riverlea. One hundred and fifty seven mothers were interviewed in their homes using a structured questionnaire. The results reveal a picture where the percentage of 'broken' or single mother families is high. There is overcrowding in the homes combined with a low level of education and employment in mainly non-skilled, low-paid jobs. The utilisation of existing dental services was poor despite the fact that 43 per cent of the families are members of medical aid schemes. Almost one third of the mothers were edentulous. Although cost and other factors were cited as barriers for not 'going to the dentist', most of the respondents have a symptomatic approach to oral health which might be responsible for poor utilisation. The 'lay referral system' for obtaining information was common and teachers played a role in this process. The study identified various factors that adversely affect the process of development of good oral health and related behaviour in the home environment. Schools and supportive community networks as well as outside organizations could be enlisted to take part in the efforts to overcome the barriers identified and improve the situation.     

Polyoma virus-induced murine odontogenic tumors.

Neonatal mouse pups were injected subcutaneously with polyoma virus to induce odontogenic tumors. This treatment resulted in a spectrum of tumors that arose in organs dependent upon epithelial-mesenchymal interactions for their organogenesis, which included the teeth, salivary glands, thymus, and lacrimal glands. In addition, several odontogenic tumors with a histologic resemblance to ameloblastoma were identified and analyzed with respect to the presence of markers specific for various stages of ameloblast differentiation. Immunodetection analyses of the odontogenic tumors identified fibronectin and laminin, typical of basement membrane organization during early tooth organogenesis. These same tumors failed to express amelogenin, a gene whose expression is limited to differentiated ameloblasts. In contrast, a 47 kDa enamelin-like polypeptide was identified with the use of an antienamelin antibody. These data were interpreted to suggest that the polyoma virus truncated the differentiation pathway for these odontogenic tissues at an early stage of their development and retained the expression of basement membrane components and the enamelin-like polypeptides, yet excluded expression of amelogenin gene products. This observation suggests that polyoma viral transformation may dysregulate odontogenic tissue interactions and produce tumors composed of cells arrested at a specific stage in their development.     

Microleakage Evaluation in Amalgam Restorations Used with Bases

Marginal leakage in amalgam restorations often precedes the development of secondary caries. One potential way to improve the marginal seal of such restorations, and thus minimize the risk of carles development, is to apply a glassionomer base prior to amalgam placement.
This study compared microleakage resistance among amalgam restorations placed with and without light-cured glass-ionomer base materials. Preparations were made in extracted human molar teeth. Four groups were studied, including copal varnish, which was used as a control. All specimens were restored with amalgam. Results indicated significantly greater leakage at the cavity wall/base interface for restorations with a copal varnish cavity liner than for those with a glass-ionomer base. Leakage differences among bases were also found at the amalgam/base interface. Best results were obtained with a dual-cure resin-based system. These samples showed minimal leakage at both the cavity wall/base and the base/amalgam interfaces. These findings suggest that light-cured glass-ionomer bases can be effective in the prevention of microleakage in amalgam restorations.