A comparison of the effectiveness of two systems for the prevention of radiation caries.

The purpose of this study was to compare the effectiveness of two systems for the prevention of dental caries in patients who have received radiation treatment (mean number of rads; 5672 +/- 1113) for head and neck cancer. The baseline examination of 184 dentulous patients included measures of DMFS and the Root Caries Index (RCI), field of radiation, gingival inflammation, oral hygiene status, pocket depth and attachment loss. The patients were assigned randomly into two treatment groups. One group was instructed to use 0.4% Sn2 gel while toothbrushing everyday, and the other group was instructed to use a 1.1% neutral NaF gel for three months, followed by twice daily rinsing with a remineralizing mouthrinse (Salminsol Solutions, Iowa City, Iowa). One hundred and forty-three patients were re-examined after one-year, and 69, 56 and 18 patients continued in the NaF gel/remineralizing mouthrinse, SnF2 and non-compliant groups, respectively. Inter-group comparisons showed that the incidence of MT, DMFT, and DF surfaced, and the RCI were significantly higher in the non-compliant group compared to either the SnF2 or NaF gel/remineralizing mouthrinse groups (P less than 0.05). Also, the NaF gel/remineralizing mouthrinse group demonstrated a significantly higher incidence of carious root surfaces compared to the SnF2 group (P less than 0.05). Also the incidence of radiation caries was significantly higher when the field of radiation exposed a greater surface area of the major salivary glands.(ABSTRACT TRUNCATED AT 250 WORDS)

In vitro susceptibilities of oral bacterial isolates to spiramycin.

Four hundred strains of oral bacteria were tested for their susceptibility to spiramycin. Actinobacillus actinomycetemcomitans and most species of Lactobacillus were resistant to the antibiotic. All strains of cariogenic Streptococcus mutans and most strains of bacterial species implicated in adult chronic periodontitis (Bacteroides gingivalis, B. intermedius, and Treponema denticola) were susceptible to spiramycin.

Effects of adjunctive treatment of periodontitis with tetracycline and spiramycin.

The present study was undertaken to compare the efficacy of two antibiotics, spiramycin and tetracycline, with a placebo when used adjunctively with scaling and root planing in the treatment of advanced adult chronic periodontitis. This was a double-blind, parallel, randomized trial with one factor (drug) at three levels. Ninety-six patients (mean age 46 +/- 1) were randomly assigned into one of three groups. All groups were scaled and root planed with each respective group receiving either spiramycin, tetracycline, or a placebo for 2 weeks. Two sites with probing depth of at least 7 mm were evaluated and the following clinical parameters were measured at baseline, 2, 8, 12, and 24 weeks: plaque index, bleeding on probing, crevicular fluid, probing depth, and change in the attachment level. The changes in the subgingival bacteria were monitored also using a differential staining technique. Seventy-nine patients completed the study. At the end of 24 weeks, although all three groups had shown clinical improvement when compared to the baseline data, there were no significant intergroup differences in any of the clinical parameters measured. While the proportion of spirochetes were significantly decreased (P less than 0.05) at 2- and 8-week intervals in both tetracycline and spiramycin groups (26% to 0.04% and 28% to 0.04%, respectively), compared to the placebo group (30% to 7%), only in the spiramycin group was the proportion of spirochetes significantly lower than the placebo group at the 24-week interval (3% and 11%, respectively). At week 24, the proportion of spirochetes in the tetracycline group had rebounded to 7%, which was not significantly different from the placebo group.(ABSTRACT TRUNCATED AT 250 WORDS)

Synthesis and secretion of phospholipase C by oral spirochetes.

Four strains of oral treponemes and Treponema phagedenis Reiter synthesize and secrete phospholipase C (PLC), which was detected by the hydrolysis of p-nitrophenylphosphorylcholine. PLC was detected in gingival crevicular fluid from diseased but not from healthy sulci. The initiation and progression of periodontal lesions may begin with the hydrolysis of membrane phospholipids by PLC.

Comparison of spiramycin and tetracycline used adjunctively in the treatment of advanced chronic periodontitis.

This study was designed to compare both clinical and microbiological changes during the treatment of advanced periodontal disease with mechanical debridement, with or without the adjunctive use of either spiramycin or tetracycline. The study, which included 96 patients with advanced periodontitis, was performed as a controlled double-blind parallel randomized trial. All patients received thorough scaling and root planing as well as adjunctive placebo or spiramycin or tetracycline. Probing depth measurements, attachment level changes, plaque level, gingival crevicular fluid, bleeding on probing and microbiological evaluation were carried out at baseline, 2-, 8-, 12- and 24-week visits. Seventy-nine patients (24 placebo, 27 tetracycline and 28 spiramycin) completed the study. At 24 weeks there were no intergroup differences in the improvement of any of the clinical parameters. Spiramycin was the only antibiotic which produced a significantly greater decrease in the proportion of spirochaetes than the placebo group at the 24-week visit. It was concluded that mechanical debridement alone was sufficient in decreasing the subgingival bacteria to a level which would result in the return to periodontal health. The study was not long enough to determine whether or not the difference in spirochaete level was an indication that the spiramycin group would have maintained the benefits of treatment for a longer time.

Host factors in juvenile periodontitis.

This study was undertaken to determine whether defects in leukocyte function or in genes at the MHC play a role in the etiology of either localized (LJP) or generalized (GJP) juvenile periodontitis. Thirteen LJP and five GJP patients (ranging in age from 13 to 22 years) and their matched controls were compared with respect to selected leukocyte functions and HLA phenotypic frequencies. The results of these studies indicated that there were significant decreases in the phagocytic and chemotactic abilities of polymorphonuclear leukocytes (PMN) in both LJP and GJP. All JP patients displayed intrinsic cell defects in chemotaxis compared with controls; in addition, some patients displayed multiple defects, including those which were serum-associated. Also, there appeared to be a significant association between JP and HLA-DR2 and HLA-A33 phenotypes. Fifty percent of the JP patients were HLA-DR2-positive, whereas only six percent of the matched controls were positive. Thirty-six percent of JP patients were HLA-A33-positive, whereas none of the controls was positive. The association seen with DR2 may be due to sampling, since there were no significant differences between the JP cases and a larger unmatched control sample which was not evaluated for periodontal disease. We conclude from these data that increased susceptibility of some patients to a very aggressive and destructive form of periodontal disease (JP) is based on defects in PMN responsiveness. Further investigations are necessary to determine whether these defects are under genetic control.

Fluoride-treated roots and viability and attachment of human gingival fibroblasts.

Topical fluoride treatment is used to help prevent root caries. It may also be useful in periodontal therapy because of its antimicrobial property. In addition, for therapeutic new attachment to occur, the fibroblasts approximating the treated root surface should remain viable, and should also be able to attach and grow onto the treated root surface. These conditions, at least, are required for fluoride not to interfere with new attachment. This study was designed to determine whether treatment of roots with fluoride adversely affects human gingival fibroblasts in culture; and what effect fluoride treatment has on attachment and growth of cells to the root surface. Cells originally obtained from human gingiva were allowed to grow to confluency in multi-well tissue culture petri dishes, and were then incubated for 24 hr in the presence of root sections as follows: (1) no treatment; (2) root-planed only; (3) 2% NaF only; (4) root-planed + 2% NaF; (5) root-planed + citric acid, pH 1 + 2% NaF. In addition, cells were plated onto roots similarly treated and were subsequently allowed to incubate for 72 hr. Viability of cells was determined by exclusion of vital dye and 51Cr retention. Attachment and growth of cells were determined by histology and scanning electron microscopy. Results indicated that, after 24 hours' exposure, there was little or no difference in cell viability between different treatment groups and control cultures. Also, all roots which had been planed accommodated cell attachment, regardless of additional treatment rendered.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of various root surface treatments on the attachment and growth of human gingival fibroblasts: histologic and scanning electron microscopic evaluation.

Human teeth extracted because of advanced periodontal disease were obtained. The portions of the roots which had been exposed in periodontal pockets were either untreated or were treated with root planing or citric acid, or root planing followed by citric acid. Human gingival fibroblasts were then added to the roots so treated and were allowed to incubate for 72 h. The ability of cells to attach to and grow onto these roots was assessed by means of gross evaluation of staining intensity and by histologic and scanning electron microscopic observation. The results of multiple experiments in each root-treatment category indicated that only roots which had been planed, whether or not citric acid demineralization was used, promoted cell attachment and growth. In addition, there were no discernible morphologic differences in the cells which were plated onto roots which were root planed only, compared to those which were root planed and citric-acid treated. In both situations too, the cells displayed morphology typical of human gingival fibroblasts in culture.