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OBJECTIVES: Oral bacteria implying a natural resistance may deteriorate the antibacterial efficacy of chlorhexidine on cariogenic microorganisms. Xylitol, mostly applied via chewing gum, is known to possess favorable plaque-reducing properties. The aim of this study was to investigate the effect of a xylitol rinse formulated as pure solution or combined with chlorhexidine on the viability of Streptococcus sanguis (early colonizer of human teeth) and Streptococcus mutans (the most causal strain for caries) during initial steps of biofilm formation. METHOD AND MATERIALS: After exposure to the test solutions, the bacteria suspended in human sterile saliva were allowed to attach to human enamel slides for 60 minutes in a preclinical flow chamber system. The bacterial vitality of suspended and attached cells was monitored using 2 fluorescent DNA stains by epifluorescence microscopy. Further parameters measured were the total bacterial cell counts on enamel slides and growth of suspended streptococci. RESULTS: The sensitivity of S mutans to pure chlorhexidine or in combination with xylitol is contrary to the natural resistance of S sanguis to chlorhexidine. The combination of xylitol/chlorhexidine showed a statistically significant antivital effect on S sanguis cells compared to the pure agents xylitol and chlorhexidine. The bacterial cell density on enamel and bacterial reproduction on agar plates were similarly affected by the combination of xylitol/chlorhexidine or the single substances. CONCLUSION: The newly discovered synergistic antivital effect of xylitol combined with chlorhexidine may contribute to the favorable potential of xylitol use for the improvement of new formulations of caries-preventive mouthrinses. [ABSTRACT FROM AUTHOR]

Treatment of intrabony periodontal defects with an enamel matrix derivative (EMD) has been shown to predictably enhance periodontal regeneration. The aim of the present study was to evaluate the 4-year results following treatment of intrabony defects with EMD. Thirty-three patients with a total of 46 intrabony defects were treated. Each patient exhibited at least one intrabony defect with a probing depth > or = 6 mm as identified by probing and on radiographs. The following clinical parameters were evaluated prior to and 1 and 4 years after treatment: probing depth, recession of the gingival margin, and clinical attachment level. The primary outcome variable was clinical attachment. Mean probing depth was reduced from 8.1 +/- 1.8 mm to 3.8 - +/-.2 mm at 1 year and to 4.0 +/- 1.2 mm at 4 years. No statistically significant differences were found between the mean probing depth 1 and 4 years postoperative. At 1 year, the mean recession increased from 1.9 +/- 1.5 mm to 3.2 +/- 1.8 mm; at 4 years, it was 2.8 +/- 1.2 mm, a statistically significant improvement compared to the 1-year results, but still significantly increased compared to the baseline. The mean attachment level changed from 10.0 +/- 2.4 mm to 7.0 +/- 2.1 mm at 1 year and 6.8 +/- 1.9 mm at 4 years (no statistically significant difference). The clinical improvements obtained following treatment with EMD can be maintained over a 4-year period. [ABSTRACT FROM AUTHOR]

The aim of the present study was to evaluate clinically and histologically the treatment of intrabony periodontal defects with a bioresorbable membrane barrier. Fifty-two intrabony periodontal defects were treated according to the principles of guided tissue regeneration (GTR) with a bioresorbable membrane. Results were evaluated by assessing probing pocket depth, recession of the gingival margin, and clinical attachment level at baseline and at 1 and 2 years after therapy. Bone level changes were evaluated radiographically. The postoperative phase was uneventful in all cases. There was a mean probing pocket depth reduction from 8.4 to 3.6 mm, a mean increase of gingival margin recession from 1.5 to 3.0 mm, and a mean clinical attachment level change from 9.9 to 6.5 mm. Mean attachment gain was 3.4 mm. Two teeth scheduled for extraction were also treated with the same bioresorbable membrane. The histologic analysis 6 months after treatment revealed the formation of new connective tissue attachment and new alveolar bone in both cases. Based on the histologic findings it can be concluded that the clinical improvements following GTR with this type of bioresorbable membrane may represent, at least in part, true periodontal regeneration. [ABSTRACT FROM AUTHOR]

AIM: The purpose of the present study was to compare clinically the treatment of deep intra-bony defects with a combination of a composite bovine-derived xenograft (BDX Coll) and a bioresorbable collagen membrane [guided tissue regeneration (GTR)] to access flap surgery only. METHODS: Thirty-two patients, each of whom displayed one intra-bony defect, were treated either with BDX Coll+GTR (test) or with access flap surgery (control). The results were evaluated at 1 year following therapy. RESULTS: No differences in any of the investigated parameters were observed at baseline between the two groups. Healing was uneventful in all patients. At 1 year after therapy, the test group showed a reduction in the mean probing depth (PD) from 8.3+/-1.5 to 2.9+/-1.3 mm (p<0.001) and a change in the mean clinical attachment level (CAL) from 9.4+/-1.3 to 5.3+/-1.5 mm (p<0.0001). In the control group, the mean PD was reduced from 8.0+/-1.2 to 4.4+/-1.7 mm (p<0.001) and the mean CAL changed from 9.6+/-1.3 to 7.9+/-1.6 mm (p<0.01). The test treatment resulted in statistically higher PD reductions (p< or =0.05) and CAL gains (p<0.001) than the control one. In the test group, all sites (100%) gained at least 3 mm of CAL. In this group, a CAL gain of 3 or 4 mm was measured at 10 sites (62%), whereas at six sites (38%), the CAL gain was 5 or 6 mm. In the control group, no CAL gain occurred at three sites (19%), whereas at 10 sites (62%), the CAL gain was only 1 or 2 mm. A CAL gain of 3 mm was measured in three defects (19%). CONCLUSIONS: Within the limits of the present study, it can be concluded that the combination of BDX Coll+GTR resulted in significantly higher CAL gains than treatment with access flap surgery alone, and thus appears to be a suitable alternative for treating intra-bony periodontal defects. [ABSTRACT FROM AUTHOR]

BACKGROUND: Treatment with enamel matrix proteins (EMD) or guided tissue regeneration (GTR) has been shown to enhance periodontal regeneration. However, until now there are limited data on the long-term results following these treatment modalities. Aim: The aim of the present clinical study was to present the 5-year results following treatment of intrabony defects with EMD, GTR, combination of EMD and GTR, and open flap debridement (OFD). MATERIAL AND METHODS: Forty-two patients, each of whom displayed one intrabony defect of a probing depth of at least 6 mm, were randomly treated with one of the four treatment modalities. The following parameters were evaluated prior to surgery, at 1 year and at 5 years after: plaque index, gingival index, bleeding on probing, probing pocket depth (PPD), gingival recession, and clinical attachment level (CAL). No statistically significant differences in any of the parameters were observed at baseline between the four groups. RESULTS: The sites treated with EMD demonstrated a mean CAL gain of 3.4+/-1.1 mm (p<0.001) and of 2.9+/-1.6 mm (p<0.001) at 1 and 5 years, respectively. The sites treated with GTR showed a mean CAL gain of 3.2+/-0.8 (p<0.001) at 1 year and of 2.7+/-0.9 mm (p<0.001) at 5 years. The mean CAL gain at sites treated with EMD+GTR was 3.0+/-1.0 mm (p<0.001) and 2.6+/-0.7 mm (p<0.001) at 1 and 5 years, respectively. The sites treated with OFD demonstrated a mean CAL gain of 1.6+/-1.0 mm (p<0.001) at 1 year and 1.3+/-1.2 mm (p<0.001) at 5 years. At 1 year, the only statistically significant difference between the four different treatments was found in terms of PPD reduction and CAL gain between EMD and OFD (p<0.05). However, at 5 years there were no statistically significant differences in any of the investigated parameters between the four different treatments. CONCLUSION: Within the limits of the present study, it may be concluded that the short-term clinical results following treatment with EMD, GTR, EMD+GTR, and OFD can be maintained over a period of 5 years. [ABSTRACT FROM AUTHOR]

OBJECTIVES: The aim of this prospective, randomized, controlled clinical study was to compare the effectiveness of a newly developed ultrasonic device to that of scaling and root planing for non-surgical periodontal treatment. MATERIAL AND METHODS: Thirty-eight patients with moderate to advanced chronic periodontal disease were treated according to an 'one-stage procedure' with either a newly developed ultrasonic device (VUS) (Vector-ultrasonic system) or scaling and root planing (SRP) using hand instruments. Clinical assessments by plaque index (PlI), gingival index (GI), bleeding on probing (BOP), probing depth (PD), gingival recession (GR), and clinical attachment level (CAL) were made prior to and at 6 months after treatment. Differences in clinical parameters were analyzed using the Wilcoxon signed ranks test and Mann and Whitney U-test. RESULTS: No differences in any of the investigated parameters were observed at baseline between the two groups. The mean value of BOP decreased in the VUS group from 32% at baseline to 20% after 6 months (p<0.001) and in the SRP group from 30% at baseline to 18% after 6 months (p<0.001).The results have shown that at moderately deep sites (initial PD 4-5 mm) mean CAL changed in the test group from 4.6+/-1.2 to 4.2+/-1.6 mm (p< 0.001) and in the control group from 4.8+/-1.3 to 4.4+/-1.5 mm (p<0.001). At deep sites (initial PD>6 mm) mean CAL changed in the test group from 8.5+/-1.9 to 7.9+/-2.4 mm (p<0.001) and in the control group from 7.9+/-1.6 to 7.2+/-2.2 mm (p<0.001). No statistically significant differences in any of the investigated parameters were found between the two groups. CONCLUSION: Non-surgical periodontal therapy with the tested ultrasonic device may lead to clinical improvements comparable to those obtained with conventional hand instruments. [ABSTRACT FROM AUTHOR]

The anti-plaque. anti-gingivitis and anti-microbial efficacies of a phenolic compound (Listcrine®) and 2 different amine/stannous fluoride mouthwashes (Meridol® I, II) were compared when these solutions were used in addition to usual toothcleaning. A placebo preparation was utilized as a negative control and a chlorhexidine solution as a positive control in this double-blind study. After professional toothcleanling, 49 volunteers continued their habitual, self- performed and non-supervised oral hygiene for a period of 2 weeks, in order to have a more standard baseline. At day 0. they began to rinse twice daily with 1 of the 5 mouthwashes. After 3 weeks of rinsing, plaque indices remained the lowest in the chlorhexidine and the Meridol® I groups, while subjects using Listerine® or Meridol® II demonstrated similar indices significantly lower than that of individuals rinsing with the placebo solution. Through this period, the gingival index scores were similar in the Meridol® Listerine® and chlorhexidine groups. At day 21, the mean GI scores in the chlorhexidine group were significantly lower than the scores in the placebo group. The plaque vitality scores showed a bacterial effect in vivo of chlorhexidine and, to a lesser extent, of the Meridol® solutions. No substantial evidence of an antibacterial effect in vivo was found for Listerine®. This study has demonstrated that when mouthrinses are used to supplement habitual mechanical oral hygiene, chlorhexidine remains the most powerful solution. Furthermore, it was also shown that a combination of habitual self-performed and non-supervised oral hygiene with Meridol® or Listerine® is more beneficial for plaque control than the use of mechanical oral hygiene alone. [ABSTRACT FROM AUTHOR]

The aim of the present study was to compare stereologically the histopathologic variations following 3 weeks of chemical (chlorhexidine) or mechanical plaque control. 18 students and dental hygienists volunteered for this investigation. After prophylaxis, they performed optimal oral hygiene to reach mean plaque and gingival indices approaching 0. Six of them then performed mechanical plaque control of 3 weeks (control), while the other 12 rinsed 3 times daily with a 0.12% chloridixidine solution (test). At days 0 and 21, the plaque index (PlI), the gingival index (Gl) and the gingival exudate flow rate (GEFR) were assessed and biopsies were obtained from buccal sites. Point-counting procedures were performed at 2 different levels of magnification on light microscopic sections to estimate the volume fractions of epithelium, infiltrated and non-infiltrated connective tissue, and collagen. The relative numbers of fibroblasts, polymorphonuclear neutrophils, lymphocytes, plasma cells, macrophages and mast cells were estimated by counting the number of nuclear profiles of these cells in a specific connective tissue area adjacent to the apical termination of the junctional epithelium. After 21 days, the PlIs of the test subjects were significantly higher than the PlIs of the controls, but their Gl were similar. At the end of the experimental period, the various volume fractions and %s of cell profiles remained stable with the exception of an increase in the %s of lymphocytes in the test group. This study has shown that, clinically as well as histologically, the daily use of chlorhexidine for a 3-week period is equally effecient as optimal mechanical tooth cleaning in maintaining a healthy gingiva in the buccal sites investigated. [ABSTRACT FROM AUTHOR]

The aim of the present study was to investigate stereologically the histologic alterations occurring during gingival healing after experimental gingivitis and to compare clinical parameters with histological findings. 8 dental students volunteered for the investigation. After a prophylaxis, they performed optimal oral hygiene to reach mean plaque and gingival indices approaching zero. They then abolished all oral hygiene procedures for a period of 21 days. After this experimental gingivitis phase, they again performed optimal oral hygiene for 8 days to restore gingival health. At days 0, 1, 2, 4 and 8 after experimental gingivitis, the plaque index (PlI), the gingival index (GI) and the gingival exudate flow rate (GEFR) were assessed and their buccal gingiva was biopsied. Point counting procedures were performed at 2 different levels of magnification on light microscopic sections to estimate the volume fractions of epithelium, infiltrated and non-infiltrated connective tissue, and collagen. The relative numbers of fibroblasts, polymorphonuclear neutrophils, lymphocytes, plasma cells and macrophages were estimated by counting the number of profiles of these cells in a specific connective tissue area adjacent to the apical end of the junctional epithelium. A rapid drop in the PlI was noted with increasing time after oral hygiene, followed by a slower decrease in the GI and GEFR scores. The histological picture during the entire experiment was that of an initial gingival lesion. At day 0, no chronic inflammation of the gingiva characterized by a predominance of plasma cells was observed. After resumption of oral hygiene when the relative cell numbers at day 0 and day 8 were compared, only an increase in the PMN population was observed. As GI and GEFR scores decreased no significant changes were noted in the relative numbers of the various cell types. These observations suggest that the "physiogenesis during experimental health" appears first clinically and then histologically, and hence, it may take more than 8 days to observe significant variations in cell populations. [ABSTRACT FROM AUTHOR]

The polymorphonuclear neturophil (PMN) appears to be an important cell in the protection of the host form pathogenic periodontal micro-organisms. The purpose of the present histological studies was to observe the emigration of the PMN from the gingival vessels to the periodontal pocket during gingivitis and ligature-induced periodontitis in the cynomolgus monkey. 2 adult female monkeys were treated by application of a silk ligature around selected posterior teeth. After 9 weeks, the monkeys were perfused and block sections of both ligated (early periodontitis) and non-ligated (gingivitis) sites were obtained, cut into smaller blocks containing a single interdental area (N = 15 for periodontitis, N = 5 for gingivitis) and processed for light and electron microscopic observations. Morphologically, no differences in PMNs between gingivitis and periodontitis were observed and therefore the following description applies to both disease states. In the vessels, the endothelial cells appeared to be actively involved in PMB emigration, maintaining long processes which surrounded the PMNs. Within the connective tissue, the PMNs maintained their typical morphology which included polylobated nuclei and numerous lysosomal granules. Many intact PMNs were observed intercellulary within the connective tissue and the epithelium. Within the periodontal pocket, a multiplayer of PMNs surrounded the plaque mass. Cells with numerous bacteria-containing phagolysosomes were observed with increasing frequency as they approached the plaque. Deeper within the bacterial deposit, PMNs were seen in varying stages of degeneration. These histologic studies, when interpreted in the light of reports of severe, rapidly-progressive periodontitis in patients with PMN disorders, suggest that the interaction of PMNs with bacterial plaque may serve to maintain a defensive boundary which protects the host tissues form irreversible destruction. [ABSTRACT FROM AUTHOR]

The aim of the present study was to compare the effect on plaque growth and gingival response of Meridol, an amine/stannous fluoride solution, during a three-month investigation, with those of a placebo preparation as a negative control and a chlorhexidine solution as a positive control, in a double-blind study. After having their teeth professionally cleaned, 36 volunteers continued their usual oral hygiene for a period of two weeks. Their teeth were then polished again (month 0) after which they rinsed twice daily (morning and evening) with one of the three mouthrinses in addition to their habitual toothcleaning. After three months of rinsing, plaque indices remained lowest in the chlorhexidine group, although the subjects using Meridol had indices significantly lower than those of individuals rinsing with the placebo solution. The gingival index scores in the Meridol group were higher than in the chlorhexidine group and lower than in the placebo group. The plaque vitality scores showed a bactericidal effect in vivo with chlorhexidine and Meridol during the entire experiment. The use of Meridol resulted in more toothstaining than with the placebo, but significantly less than with chlorhexidine. This study demonstrated that Meridol reduced plaque accumulation, retarded gingivitis development, possessed a definite bactericidal action, and produced only slight toothstaining. [ABSTRACT FROM AUTHOR]

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The objective of this investigation was to determine the microbial generation time during early human supragingival plaque formation. On 2 occasions, 13 participants refrained from all oral hygiene measures for periods of 1, 2, 4, 8, 24 and 72 h. Plaque was sampled from defined areas of the teeth 13, 14, 15, 23, 24 and 25. Two independent methods were used to estimate the total number of viable cells: colony-forming units BCVF, total bacterial counts (BC) as enumerated by microscopic examination, and the percentage of vital bacteria using a vital fluorescence technique (VF) were recorded. The total number of vital microorganisms was calculated by BCVF (= BC × VF). The generation time based on either colony-forming units or BCVF increased significantly with plaque age. During the first interval (1-4 h), the microbial multiplication took slightly less than 1 h. After the establishment of a more mature plaque (24 72 h), the replicating time was between 12.5 h (BCVF) and 14.8 h (colony-forming units). It was concluded that the microbial generation time recorded at the initial stages of plaque formation is considerably lower than that found in older plaque. [ABSTRACT FROM AUTHOR]

A sample of 170 responsive residents of seniors housing centres in Winnipeg, Canada, were studied, (>65 years, mean 82 years), with the objectives of relating their dental state to their perception of need and uptake of service. Only 6% rated their oral health as poor, 46% reported a dental visit within the previous year and 68% felt they needed dental treatment. A lack of perceived need (88%) was the primary reason why dental care was not sought more frequently. Hygiene practices revealed that only 7% brushed < 1 time/day, 60% never flossed, 14% cleaned their dentures <1 time/day, and 42% slept with their dentures. Dental histories showed that examination (94%), prosthodontic treatment (76%), and restorative services (65%) were the most commonly sought treatments. Perceived dental needs included prosthodontic treatment (39%), periodontal/prophylactic treatment (10%), restorative treatment (9%) and pain relief (9%). Study subjects had 2.8 decayed teeth, a DMFT of 25.1, and a Root Caries Index of 38%. CPITN scores of 3 or 4 in at least one sextant were found in 80% of subjects. Of the 41% edentulous, all wore complete dentures but 15% of complete upper dentures and 51% of complete lower dentures fitted poorly. Of the partial dentures, 20% fitted poorly. Soft tissue anomalies were seen in 67% of subjects and 47% had TMJ anomalies. Overall, 77% of edentulous subjects and all dentate subjects required some dental treatment even though 46% had seen a dentist within the preceding year. It is concluded that appropriate management of such people needs further attention. [ABSTRACT FROM AUTHOR]

The medical and dental status, and drug utilisation patterns of Canadian Inuit elders (60+ years) were evaluated. Inuit elders averaged 6.3 medical conditions per person, primarily nervous systems-sense organ deficits, respiratory problems and systemic infections. The mean number of drugs being used was 2.5 per person, primarily analgesics, bronchodilators and antibiotics. Poorly fitting dentures, and high levels of tooth decay, periodontal disease, soft tissue and TMJ anomalies were documented. Compared to older southern Canadians, the medical and dental findings for these Inuit elders were different. Drug utilisation rates were consistent with older southern Canadians, but different drugs were taken. [ABSTRACT FROM AUTHOR]

Although vital plaque micro-organisms are part of the natural ecosystem in the oral cavity they are also the key factor in the development of diseases induced by the human dental plaque. In a previous study (9) the portion of vital bacteria related to the total number of plaque micro-organisms (i.e. the microbial vitality) appeared low in small plaque samples. The objective of this investigation was to determine the exact relationship of microbial vitality and age of supragingival plaque during the early phases of human dental plaque formation Between intervals of optimal oral hygiene, thirteen participants refrained from all oral hygiene measures for periods of 1, 2. 4, 8, 24 and 72 h. Plaque was completely sampled from a defined area situated on the vestibular surface of the teeth 13, 14, 15, 23, 24 and 25. The pooled plaque from these areas was immediately processed Total bacterial counts (BC) as enumerated by darkfield microscopy, and colony-forming units (CFU) were recorded The microbial vitality was calculated indirectly as plating efficiency (PE=CFU per BC) and directly assessed using a vital fluorescence VF technique. In the 1 h old plaque samples the median values of PE and VF were 29% and 18%, respectively. Thereafter, the microbial vitality increased significantly with plaque age. The 24 h old plaque, samples yielded values of 77% (PE) and 62% (VF). It was concluded that the microbial vitality of the early dental plaque investigated was considerably lower compared to that of a mote mature plaque. [ABSTRACT FROM AUTHOR]

Comparisons between plaque index (PII) and bacterial counts have been made already, however, these did not take into account the area used for plaque sampling. The objective of the present study was to determine the correlation between the PII score, the number of bacteria and the bacterial plaque vitality when dental plaque was repeatedly sampled from the same area in each subject during early plaque accumulation. Between intervals of optimal oral hygiene, 10 participants refrained from all oral hygiene measures for periods of 1, 2. 3, 4 and 5 days. The PII was recorded on the vestibular surface of all first premolars as local PII:LS. For statistical reasons, the scores of the independent variable LS were added for each subject giving LS* values ranging from 0 to 8. The plaque sampled from this specific surface was circumscribed by the marginal gingiva and an acrylic splint, giving reproducible areas for plaque collection. Total microscopic bacterial counts (BC), colony farming units ot anaerobes (CFUan) and aerobes (CFUae), and proportions of vital bacteria (VF) were compared with LS* values. BC and LS* values were strongly correlated. CFUan and CFUae increased significantly with LS*, but this increase was higher for LS* 0 to 4 than for LS* 4 to 8. The ratio between vital and dead microorganisms, assessed by two different methods, was low when an LS* of 0 was recorded, with higher ratios registered for LS* values 4 and 8. [ABSTRACT FROM AUTHOR]

PMN elastase concentration of gingival crevicular fluid (GCF) was investigated in 11 healthy volunteers before professional tooth cleaning and after a 5-week period of intensive oral hygiene. GCF was collected using filter paper strips and the enzyme concentration was evaluated by the ELISA-technique. Intensive daily oral hygiene led to a considerable improvement in the clinical indices and to a reduction in the concentration of clastase in GCF Despite the changes in the oral hygiene status, functional elastase was still present in the samples at the end of the experiment. This could mean that even at clinically healthy sites there is a lack of alpha-1-proteinase inhibitor, the major serum protein inactivating PMN elastase. [ABSTRACT FROM AUTHOR]

It has been suggested that the vascular alterations found in inflamed gingiva may be of significance in the enhanced extension of the pathological process into the periodontium. The purpose of this investigation was to measured the changes in blood vascular volume occurring in gingiva with the onset of gingivitis and its resolution. Twenty-six individuals participated in this study. Gingival biopsies were taken following a 21-day experimental gingivitis, following resolution of a 21-d experimental gingivitis and during a 6-month experimental gingivitis and a 6-month period of optimal oral hygiene. A total of 126 biopsies was obtained, from which 378 sections were cut at 2 μm lot stereological analysis. At low magnification, reference volumes were estimated using point counting procedures and expressed as mm3 of gingiva per mm length of vestibular gingiva, in a vestibulo-lingual plane. At higher magnification the ratio between the volume of vessels and connective tissue was calculated. The final results were expressed as mm3 of vessels per mm length of vestibular gingiva, in a vestibulo-lingual plane. The mean vessel volume expressed per unit length of vestibular gingiva ranged from 0.010 to 0.024 mm3/mm. No statistically significant differences in vestibular volumes were found between inflamed and non-inflamed gingiva. It was concluded that the changes in vascular architecture during early gingivitis described in the literature had either taken place in the subjects prior to the time of experimentation or that any vascular changes (cytologie or functional) which had taken place may be compensatory for the changes in architecture described in the literatures. [ABSTRACT FROM AUTHOR]

After prophylaxis, 5 dent hygienists optimal oral hygiene under supervision for 6 months. At months 0,1,4 and 6, Plaque Index Gingival Extudate Flow Rate and Gingival Index were assessed and a buccal biopsy of their gingiva taken. Point counting procedures were performed at 2 different levels of maginification to estimate the volume densities of epithelium, infiltrated and non infiltrated connective tissue and collagen. The percentage of fibroblasts, polymorphonuclear nutropholic granulocytes, lymphocytes, plasma cells and macrophages were estimated by counting the number of profiles of these cells in the connective tissue area close to the apical end of the junctional epithelium. All the changes insides the tissue occurred slowly. During the 6-month period there was a continuos increase of the volume density of the epithelium in the gingiva. An increase in the percentage of fibroblasts were observed between months 1 and 4 with a decrease in the percentage of lymphoocytes and in the volume density of the infiltrated connective tissue. Between months 4 and 6 an increase of the volume density of the collagen was found together with a further increase in the percentage of fibroblast and a further decrease in the percentage of lymphocytes. After 6 months of perfect oral hygine no more plasma cells visible. This study has shown that even in presence of clinically healthy gingiva subclinical changes may take place. It appear realistic to accept the presence of a very mild gingivitis localized in an area adjacent to the attachment as compatible with gingival health. [ABSTRACT FROM AUTHOR]

The influence of chlorhexidine and Octapinol® on early plaque formation in humans was assessed in vivo. Three subjects with healthy gingiva were used. Plastic films were applied to the buccal surfaces of the maxillary right first premolars and plaque was allowed to form for either 4 or 24 hours. After 1 minute of plaque development, a drop of water, 1 % chlorhexidine or 1 % Octapinol was gently applied in situ; in the 24-h experiment an additional drop was added at 12 h. In total, 76 films were obtained, with a comparable number of specimens in each of the 6 groups. The samples were processed for light and transmission electron microscopy, using standardized techniques for area sampling and cell counting. All control films were covered by a surface coating of a cellular material in or on which bacteria, epithelial cells and leukocytes were observed. The controls and to a lesser extent the Octapinol samples exhibited a significant increase in bacterial count between 4 and 24 h. However, the number of bacteria in the chlorhexidine samples showed only a slight increase within this period. Some microorganisms in the chlorhexidine samples appeared to be undergoing degeneration. In the Octapinol specimens the bacterial morphology was generally intact with many extracellular areas of high electron density. Chlorhexidine and Octapinol both had a qualitative effect on early plaque formation, hut only the former had a detectable quantitative effect at this initial stage of plaque accumulation. [ABSTRACT FROM AUTHOR]

The article presents a comparison between histological and clinical parameters during human experimental gingivitis. The purpose of this investigation was to study stereologically the histopathologic alterations occurring during a human experimental gingivitis, and to establish a relationship between clinical parameters and histologic findings. Eight dental students volunteered for the study. After a prophylaxis they performed optimaI oral hygiene For 3-4 weeks to reach mean plaque and gingival indices approaching zero.

The experimental gingivitis model was used to compare the antigingivitis, antiplaque, and antimicrobial efficacies of two commercially available (a phenolic and a plant alkaloid) compounds used as mouthrinses with those of a mouthrinse containing chlorhexidine digluconate. Thirty-one male and female volunteers with healthy gingivae and clean teeth ceased all oral hygiene procedures for 21 days during which they rinsed twice daily with: a) a phenolic compound (Listerine®), b) sanguinarine (Viadent®), c) 0.12% chlorhexidine digluconate, or d) a placebo mouthrinse. After 21 days of rinsing, virtually no signs of clinical gingivitis were observed in the chlorhexidine group. Subjects rinsing with Listerine, Viadent, or placebo developed clinical signs of gingivitis as measured by gingivitis occurrence, severity, and the proportion of gingival bleeding sites. At the same time, plaque accumulation was only slightly higher than at baseline in the chlorhexidine group, while the Listerine, Viadent, and placebo groups had significantly greater plaque accumulations, particularly during the initial period of treatment between day 0 and day 7. Microbiological enumeration of supragingival plaque collected at the end of the treatment period showed that chlorhexidine digluconate reduced plaque bacteria by 62-99% compared to the placebo group. No significant reductions in plaque bacteria were found among subjects using Listerine or Viadent. This study demonstrated that 0.12% chlorhexidine digluconate was superior to Listerine and Viadent in its ability to maintain optimal gingival health during the entire three weeks of mouthrinse use. It was of particular interest to note these effects during the final 14 to 21-day period of extreme challenge in this experimental model when gingivitis severity and bleeding site occurrence are most pronounced in the placebo group. [ABSTRACT FROM AUTHOR]

Electron microscopic observations were made on naturally occurring gingivitis, on gingivitis at non-ligated sites of an experimental animal, and on ligature-induced periodontitis in a periodontal disease model using female cynomolgus monkeys. For bath types of gingivitis specimens, a plaque associated chronic inflammatory reaction was observed, comparable to that described for the human established lesion. Bacterial accumulations on tooth surfaces were separated from the epithelium by neutrophils which exhibited variations in fine structure and extent of bacterial phagocytosis related to their proximity to the plaque. In the inflamed connective tissue of the papillac, collagen was reduced to strands extending between the cellular elements. The plasma cell was the most common inflammatory cell and had three major variations in form. With ligature-induced periodontitis, similar inflammatory features were observed in the gingiva. A complex flora like that encountered in human periodontitis was observed around and within the ligature as well as more apically in the pocket. As compared to the flora in gingivitis, more spirochetes were encountered, a larger proportion of the microorganisms appeared to be in a living state, and bacteria were in contact with the epithelial surface, rather than being walled off by the neutrophils. This seemingly more aggressive plaque was associated with an advanced lesion characterized by changes that indicated sequential destruction of the collagenous attachment to cementum and concommitant apical migration or the epithelial attachment. No bacteria were observed in the soft tissues, even in the wide intercellular spaces between the epithelial cells. [ABSTRACT FROM AUTHOR]

Histological observations were made on ligature-induced periodontitis in two adult female monkeys (Macaca fascicularis). Silk ligatures were placed around posterior teeth and the shift from gingivitis to periodontitis was followed radiographically and bacteriologically for eight and nine weeks, respectively. Fifteen tissue blocks with ligatures in situ were obtained. Following decalcification with EDTA and epon embedding, sections one micron in thickness were prepared in the mesio-distal plane to study the interproximal regions. Two additional blocks were processed for routine histology. Radiographically, progressive bone loss was observed in the interproximal regions that had a ligated tooth surface. Histologically, prominent features included supragingival and subgingival plaque (with dense accumulations of bacteria around and within the ligature), apical migration of the junctional epithelium, loss of collagen and connective tissue attachment, and osteoclastic bone resorption. A chronic inflammatory reaction was evidenced by a dense infiltration of leukocytes in the connective tissue, with a high proportion of plasma cells. Numerous polymorphonuclear leukocytes were seen in pathways between epithelial cells and in a zone around the plaque-laden ligature. These morphological observations, similar to descriptions of human periodontitis, lend support for the usefulness of this model in the study of human periodontitis. [ABSTRACT FROM AUTHOR]