No abstract

The effects of fluoride and chlorhexidine varnishes on the microflora of dental root surfaces and on the progression of root-surface caries were studied. Forty-four patients, surgically treated for advanced periodontal disease, were distributed at random among three groups. All patients received a standardized preventive treatment. Furthermore, the dentition of the patients in the two experimental groups was treated, at three-month intervals, with chlorhexidine and fluoride varnish, respectively. Patients in the control group received no additional treatment. In the experimental groups, plaque samples were collected from selected sound and carious root surfaces at baseline and at three, six, and nine months after the onset of the study. The presence of root-surface caries was scored at baseline and after one year. In addition, the texture, depth, and color of the root-surface lesions were monitored. Mutans streptococci on root surfaces were suppressed significantly (p less than 0.05) during the whole experimental period in the chlorhexidine varnish group, but not in the fluoride varnish group. A non-significant increase in the number of Actinomyces viscosus/naeslundii was noted after treatment with chlorhexidine and fluoride varnish. The increase in the number of decayed and filled root surfaces after one year was significantly lower in the experimental groups than in the control group. After treatment with chlorhexidine varnish, significantly more initial root-surface lesions had hardened than in the other groups.

In 47 patients plaque samples were taken from sound and carious root surfaces. The carious surfaces were categorized as soft or hard. In total, 70 sound, 29 hard carious and 36 soft carious surfaces were sampled and analyzed for the presence of Streptococcus sanguis, Streptococcus mutans, Actinomyces viscosus/naeslundii, Lactobacillus and Capnocytophaga species. Samples from soft carious surfaces contained significantly higher numbers of S. mutans as compared to samples from sound surfaces. The numbers of S. mutans on hard carious and sound surfaces were approximately equal. For S. sanguis and A. viscosus/naeslundii no significant differences were found. The isolation frequency of Capnocytophaga was comparatively low. Lactobacilli were only occasionally found. The results indicate that, from the above species, only S. mutans is closely related with root surface caries.

The prevalence of root surface caries was estimated in 83 patients surgically treated for periodontal disease and some relating factors were analyzed. The overall root caries index (RCI) was 6.28%. Anterior teeth in the mandible were significantly less affected than other groups of teeth. Root surfaces, divided into subgroups according to surgical treatment and length of exposure, showed no significant differences in RCI. No correlation was found between DFS-index and RCI. RCI increased with age. Concomitantly in older people more time had elapsed between the periodontal treatment and the present clinical examination. Salivary S. mutans counts and a combination of higher salivary S. mutans and lactobacilli counts were good indicators for the presence of root surface caries.

The aim of this study was to test the clinical effects of preventive regimens using fluoride and chlorhexidine on caries development in abutment teeth in patients with overdentures. 30 patients with immediate overdentures were distributed at random among three experimental groups. In these groups three different gels (placebo, fluoride, and chlorhexidine-fluoride) were tested by daily application. The patients were recalled at 6-month intervals for a period of 18 months. The life table survival ratios at patient level showed that in the chlorhexidine group caries development in the abutments was significantly reduced. In this group no caries developed. On comparison with the control group (placebo), no preventive effects of the gel were noticed for those in the fluoride group.