摘要:

The Florida Dental Care Study is a longitudinal study of changes in oral health that included at baseline 873 subjects (Ss) who had at least 1 tooth, were 45 years or older, and participated for an interview and examination. Forty-five percent of Ss had active coronal caries; 94% of the coronal carious surfaces were primary decay, and only 6% were secondary/recurrent. Ten percent of Ss had 1 or more root fragments, 16% of Ss had 1 or more teeth with restoration fractures, and 14% of Ss had 1 or more teeth with cusp fractures. Blacks, poor persons, and irregular attenders had more caries, root fragments, and cusp fractures, even though they had significantly fewer teeth. Blacks, poor persons, and irregular attenders were not at increased risk for restoration fractures, probably because fractures were associated with dental care use. These findings regarding caries and restorative treatment needs are consistent with a substantial burden in adult high-risk groups, and are relevant for dental primary health care policy.

ISSN:0008-6568    

DOI:10.1159/000262145

出版商:S. Karger AG    

年代:1996

数据来源: Karger

摘要:

Secondary caries is a major reason for the replacement of restorations. Because it is hypothesized that the development of secondary caries is closely associated with pathogenic oral bacteria, an in vitro microbial model has been developed to produce secondary carious lesions. A mixture of overnight cultures of Streptococcus mutans and Lactobacillus casei in dextrose-free trypticase soy broth, supplemented with 5% sucrose (TSBS), at 37°C was used in this model as the inoculum for the experimental groups. Uninoculated control groups were incubated with medium only. Groups of human tooth specimes restored using composite, together with their respective controls, were exposed for 7 or 12 days to circulating cycles of TSBS (30 min each, 3 times per day) and a mineral wash solution (for a total of 22.5 h per day), at 37°C. The pH of the experimental groups dropped to 4.1–4.5 during the test periods. The pH of the control groups remained at 6.8–7.0. The inoculated bacteria remained viable throughout the study. No contamination of experimental or control samples occurred. Laser scanning confocal microscopy demonstrated the development of incipient surface and wall lesions in all the specimens of experimental groups in as few as 7 days. Reproducibility of the model was confirmed in a second investigation. Therefore, it was concluded that this model can be used for studying the microbial etiology and prevention of secondary c

ISSN:0008-6568    

DOI:10.1159/000262146

出版商:S. Karger AG    

年代:1996

数据来源: Karger

摘要:

Funoran, a sulfated polysaccharide extracted from the seaweed Gloiopeltis furcata strongly inhibited the adsorption of mutans streptococci to saliva-coated hydroxyapatite (S-HA), but enhanced that of Streptococcus sanguis ATCC 10556 and Streptococcus oralis ATCC 10557. Furthermore, funoran had a strong desorption activity against mutans streptococci preadsorbed to S-HA. In the presence of sucrose, the adsorption of cells of Streptococcus sobrinus B13, Streptococcus mutans Ingbritt, and S. mutans MT8148R to S-HA was strongly inhibited by 0.01% funoran. The colonization of S. sobrinus 6715 inoculated on the molar teeth of experimental rats that were administered funoran was less frequent than that in a funoran-free group. The mean buccal and lingual, sulcal, and total caries scores of rat groups administered funoran were significantly lower than those of the funoran-free group.

ISSN:0008-6568    

DOI:10.1159/000262147

出版商:S. Karger AG    

年代:1996

数据来源: Karger

摘要:

Assessment of the acido/cariogenicity of 11 fruits and cereals was carried out using methods recommended at the San Antonio Conference: plaque pH by sampling (PS), indwelling electrode (IDE) and intra-oral cariogenicity test (ICT), together with additional tests of the total carbohydrate content of salivary expectorants, acid anion profiles of plaque, liberated maltose in plaque, total food carbohydrate and fluoride concentration. All foods within each test were compared with sucrose and sorbitol as positive and negative controls. Results for foods were ranked against sucrose for cH area under the curve for PS, for mean ratio [H+] of food versus sucrose (IDE) and mean change in indenter penetration length in enamel after exposure (ICT). Results showed that different rankings of foods were obtained with each method, with a greater degree of commonality for PS and ICT versus IDE. Factor analysis identified liberated maltose in plaque, area below the curve (PS), total food carbohydrate and plaque pH drop (PS) as being important in determining the potential cariogenicity of foods. It was concluded that each of the methods was of value and could be used to assess potential acido/cariogenicity of foods. The recommendation that it was desirable that at least two methods should be used was confirmed.

ISSN:0008-6568    

DOI:10.1159/000262148

出版商:S. Karger AG    

年代:1996

数据来源: Karger

摘要:

The acidogenic potential of a group of popular cereal-based foods and fruits and total carbohydrate content of salivary expectorants following their consumption were assessed using an indwelling electrode with telemetry and the anthrone method. Paired t tests indicated that sorbitol did not cause the plaque pH to fall as low as any of the test foods (p < 0.05) but there was no significant difference between sucrose and the test foods. Only the fruits produced less acid than sucrose. The breakfast cereals tended to yield the highest levels of total carbohydrate in the salivary expectorants although a greater percentage of original carbohydrate was retained after rice and bread. These results suggest the important effect of carbohydrate retention on plaque pH response.

ISSN:0008-6568    

DOI:10.1159/000262149

出版商:S. Karger AG    

年代:1996

数据来源: Karger

摘要:

Our earlier work demonstrated that the sweetener sucralose, C12H19CI3O8, mixed with water had no effect on intraoral plaque pH. The current study compared the effect on resting plaque pH of sucralose to sucrose when these sweeteners were used in hot coffee at equivalent sweetness levels. Twelve subjects with an identified acidogenic plaque were tested at dicrete sessions, using coffee as vehicle with: (1) sucrose; (2) sucralose; (3) sucralose plus maltodextrin (SM); (4) sucralose plus dextrose and maltodextrin (SMD), and (5) no additional sweetener. Each subject rinsed for 1 min with the test rinse, expectorated, and plaque pH was measured at six dental sites for 60 min using an antimony touch electrode method. Data were summarized for baseline pH, delta pH (baseline pH minus lowest pH attained), minimum pH, and area under the pH curve (AUC). Baseline pH was not different throughout all tests. Quantification of AUC in the various groups showed that sucralose with coffee had no statistically significant impact on plaque acidogenesis. AUC, minimum pH and delta pH were least changed by coffee and sucralose, while the SM and SMD combinations generally led to intermediate changes as compared with coffee sweetened with sucrose or sucralose. Because of its acidic nature, unsweetened coffee led to a modest pH depression, the effect of which appears to be blunted by sucralose. This study confirms that sucralose is non-acidogenic and indicates that sucralose may reduce the acidogenic potential of coffee.

ISSN:0008-6568    

DOI:10.1159/000262150

出版商:S. Karger AG    

年代:1996

数据来源: Karger

摘要:

Cavitation of enamel lesions probably represents a significant step regarding further progression of the caries process. The primary objective of this study was to examine in adolescents the macroscopical appearance of approximal surfaces with radiographic lesions and relate this to the caries activity of the individual. A second objective was to establish the clinical feasibility of a modified technique for inspection of approximal contact surfaces. The material consisted of 46 enamel lesions selected on the basis of routine bite-wing radiographs of 140 patients aged 17-18 years, available from the Public Dental Service of Lillehammer, a non-fluoridated town. Lesions close to or approaching the AD junction were classified as D2 lesions, whereas those demonstrating a shadow not more than 1 mm into the dentine were designated D3 lesions. Based on recorded treatment during the last 3 years, patients were dichotomised as caries-active (CA) if they had more than 6 new lesions involving the dentine. The remainder with little or no activity were designated modestly active (MA). A small orthodontic rubber ring was placed around the contact point of the approximal surface of interest 1 day before an impression was taken. A separation of 0.5 mm facilitated cleansing and injection of low viscosity impression material (Xantopren® L, Blue, Bayer Dental). Discontinuity in the approximal enamel surface, determined by visual inspection of stone dyes, prepared from the impressions, was classified as cavitation. The results demonstrated that in MA patients D2 lesions seldom had cavities while in CA patients cavitation was usually found both in D2 and D3 lesions. The feasibility of the impression/inspection method seems established. It is easily performed and should be considered as a diagnostic tool in borderline cases

ISSN:0008-6568    

DOI:10.1159/000262151

出版商:S. Karger AG    

年代:1996

数据来源: Karger

摘要:

Diagnosis of occlusal caries is difficult from visual and radiographic examination. The use of electrical resistance measurement has been described previously and reported to be a potentially sensitive alternative technique. This is possibly due to the decreased resistance of carious pits and fissures. The aim of this study was to validate a prototype electrical caries monitor for the diagnosis of caries in pits and fissures in vitro using a microfocal radiographic technique. Thirty discrete sites were investigated in 10 extracted molar teeth. Electrical resistance measurements were recorded at each site and thick sections (approximately 0.65 mm) prepared for microfocal radiography. Microfocal radiography indicated that six sites were sound, 10 had enamel caries and 14 dentine caries. At a resistance value of 2.2 MΩ, below which a site was regarded as carious and above which it was regarded as sound, electrical resistance measurements proved sensitive (92%) and specific (100%). Quantification of mineral content indicated that mineral loss in enamel may influence resistance measurement more than lesion depth

ISSN:0008-6568    

DOI:10.1159/000262152

出版商:S. Karger AG    

年代:1996

数据来源: Karger

摘要:

The value of imaging modalities in enabling the observer to detect proximal dental caries has been tested previously using both natural carious cavitations and mechanical defects. This study compared the ability of dentists to detect mechanically created defects and natural dental carious cavitations on the proximal surfaces of extracted teeth, and to differentiate between the two. Detection rates according to lesion depth were also investigated. There was a difference in the ability of readers to detect natural proximal dental carious cavities and mechanical defects in the proximal enamel. The odds of detecting artificial cavities was 2.92 times the odds of diagnosing natural caries cavitations. There was great variation in the ability of the dentists to identify natural and artificial lesions. According to logistic regression, when the cavity depths are equal, the mechanical defects in the proximal dental enamel are easier to identify than are natural enamel dental caries cavitations. The odds ratio charts provided from this study show the depths of mechanical and natural lesions that are comparable in diagnostic challenge. These charts might permit rough approximations to be made when comparing previously published papers that variously use both mechanical defects and natural caries. Use of poorly designed in vitro models for testing can produce a false guide to the clinical performance of diagnostic systems.

ISSN:0008-6568    

DOI:10.1159/000262153

出版商:S. Karger AG    

年代:1996

数据来源: Karger

摘要:

Young Osborne-Mendel rats were given different diets for 6 weeks. Effects of soft and rough food as well as acidic sport drink on the lingual surfaces of first mandibular molars were studied. In addition, the effect of fluoride on erosion was examined. A Jeol JSM-35 scanning electron microscope was used to visualize tooth surface ultrastructure. Intact surfaces were found in the rats given soft food and distilled water. Sport drink (pH 3.2) caused severe erosion with total loss of supragingival enamel and exposure of dentin. Attrition effects were seen on the cuspal parts of the surface when rough food was given. Tooth tissue loss was greatest in the rats given rough food and sport drink; signs of both erosion and attrition could be seen. When fluoride was added to the sport drink erosion lesions were less severe and if dentin was exposed, the dentinal tubules were partly occluded. These SEM observations support earlier studies which have suggested that erosion may alter tooth surface so that it is more susceptible to attrition; in those lesions, however, clinical diagnosis of the initial causes may be difficult.

ISSN:0008-6568    

DOI:10.1159/000262154

出版商:S. Karger AG    

年代:1996

数据来源: Karger