Occlusal wear of teeth and restorative materials. A review of classification, etiology, mechanisms of wear, and some aspects of restorative procedures

In vitro wear of resin denture teeth

STATEMENT OF PROBLEM

One of the most important physical properties of artificial teeth used in the restoration of the edentulous patient is wear resistance, and the ability of these teeth to maintain a stable occlusal relationship over time.

PURPOSE

This study compared the in vitro wear of four different resin denture teeth against human enamel.

MATERIAL AND METHODS

Five denture tooth samples opposing five enamel abraders were positioned in a mechanical wear testing device for two 5,000 cycle wear periods (total of 10,000 cycles) under a 13.4 N load. All tests were conducted in human saliva, and the wear was measured at the end of each test period.

RESULTS

The wear of the Classic and Kenson acrylic resin denture teeth was much greater than the DB Plus and MLI composite teeth after 10,000 cycles. The wear of the KENSON denture tooth was also greater than the Classic tooth. No wear differences were found between the two composite teeth.

CONCLUSIONS

The wear of DB Plus and MLI resin denture teeth was approximately 50% less than the wear of Classic and Kenson teeth when opposed by human enamel.

Erosion caused by gastroesophageal reflux: diagnostic considerations

Dental erosion occurs with a high prevalence in the general population, but its impact on prosthodontic care is often unrecognized. The etiology of dental erosion is difficult to establish because it may result from a variety of causes and may have different presentations. Our purpose was to review the literature relevant to dental erosion and to report a patient presentation in which an unusual pattern of severe erosion was the dental manifestation of asymptomatic gastroesophageal reflux disease.

Dental erosion associated with soft-drink consumption in young Saudi men

This study reports on the causative factors of dental erosion in selected high- (n = 19) and low-erosion (n = 19) subgroups of a larger random sample (n = 95) of young male Saudi military inductees. By means of a questionnaire, the role of various possible factors related to oral health in general, and to dental erosion in particular, was assessed for each participant. Clinical examination included recordings of severity of dental erosion and fluorosis, presence of buccal cervical defects and first permanent molar 'cuppings', DMFT and DMFS, visible plaque index, and gingival bleeding index. In addition, bitewing radiographs, study casts, and intraoral color transparencies were obtained for each individual. Logistic regression analysis showed a strong correlation between the presence of dental erosion and a high level of consumption of cola-type soft drinks. Other statistically significant associated factors, although of less predictive strength, were type of cleaning aid and gingival bleeding index. In subgroup comparisons, dental problems (primarily pain), number of buccal cervical defects, and number of missing teeth were significantly greater in the high- than in the low-erosion subgroup.

Dental erosion, soft-drink intake, and oral health in young Saudi men, and the development of a system for assessing erosive anterior tooth wear

The aim of the study was to investigate some aspects of the oral health of male Saudi military inductees with special reference to soft-drink consumption, dental erosion, caries and fluorosis prevalences; a second aim of the study was to develop a system for assessing dental erosion. The material comprised a random selection of 95 individuals with a mean age of 20.9 years (range, 19-25 years). A questionnaire survey was made of each individual's dietary and oral hygiene habits and general and oral health, in addition to clinical, study cast, radiographic, and photographic examinations. The results showed that soft-drink consumption in the sample (x = 247 1/year) far exceeded that found in Western populations and that professional and self-administered dental care were generally scant. Twenty-eight percent of the maxillary anterior teeth showed pronounced dental erosion. Fluorosis was a common finding, and the number of untreated carious cavities was high. DMFT (mean = 10.0; DT = 7.7; MT = 0.5; FT = 1.8) and DMFS (mean = 18.3; DS = 12.6; MS = 2.5; FS = 3.2) were higher than those of comparable Western populations and showed an approximately threefold increase over a period of about 18 years as compared with that previously reported in a similar Saudi sample. In view of the high frequencies of dental erosion, untreated carious cavities, and fluorosis reported here and the strong indication of an increasing caries prevalence, the need for serious recognition of the implications in the planning of future dental health care program is stressed.

Incisal and occlusal tooth wear in children and adolescents in a Swedish population

The material consisted of 527 randomly selected children and adolescents from the community of Jönköping, Sweden, who in 1983 reached the age of 3, 5, 10, 15, or 20 years. The degree of incisal or occlusal tooth wear was evaluated for each single tooth in accordance with the following criteria: score 0 = no wear or negligible wear of enamel; score 1 = obvious wear of enamel or wear through the enamel to the dentin in single spots; score 2 = wear of the dentin up to one-third of the crown height; and score 3 = wear of the dentin more than one-third of the crown height. In the age groups 3 and 5 years the primary dentition was studied, and in the age groups 10, 15, and 20 years the permanent dentition. In the 3-year-old children 63% and in the 5-year-olds 19% had no or slight incisal or occlusal wear in the primary dentition. In the permanent dentition the corresponding figures for the 10-, 15-, and 20-year-olds were 78%, 51%, and 35%, respectively. The 5-year-olds had the highest percentage of primary teeth with incisal or occlusal wear related to existing teeth in accordance with criteria 1-3 (32.2%), and the 10-year-olds had the lowest score for permanent teeth (2.5%). There were small or no differences in tooth wear between the sexes in these age groups. Eighteen children (17%) among the 5-year-olds had one or more teeth with wear scored 2 in the primary dentition, and one individual had 4 primary teeth scored 3. The corresponding figures for the 3-, 10-, 15-, and 20 year-olds were 2%, 1%, 7% and 6%, respectively. No permanent teeth with wear scored 3 were found in these age groups. The number of teeth with incisal or occlusal wear increased with age both in the primary and in the permanent dentition.