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Biomedical subjects

M Brecx

Publications and source records attributed to M Brecx.

At least 55 records · Page 3Linked to original sources
PubMed1995

Microbial vitality of supragingival dental plaque during initial stages of experimental gingivitis in humans.

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 more mature plaque.

Adult↗
PubMed1995

Oral health status of a population of community-dwelling older Canadians.

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.

Aged↗
PubMed1994

Repeated subgingival oxygen irrigations in untreated periodontal patients.

The aim of this study was to assess the effect of repeated subgingival oxygen irrigations in previously untreated deep periodontal pockets. 112 pockets > or = 4 mm were selected in 14 subjects. Probing attachment level and bleeding on probing were recorded, as well as the presence of disease-associated micro-organisms within the pocket. Subsequently, the pockets were irrigated with gaseous oxygen 1 x a week during a continuous 8-week period. Irrigations with nitrogen served as control. The re-evaluation of all clinical and microbiological parameters at the end of study revealed that repeated oxygen insufflations resulted in a significant clinical improvement of the periodontal baseline conditions superior to the one found in the control.

Adult↗
PubMed1994

Human dental plaque formation on plastic films. A quantitative SEM study.

The initial colonization of bacteria in previously clean teeth or artificial surfaces inserted in mouth has been reported to occur at various periods of time. Rönström et al., using light microscopy, saw that bacteria were present 10 seconds after prophylaxis. Bacterial culture studies have shown that microorganisms associated with the surface coating on tooth surfaces appeared within minutes after prophylaxis. Furthermore, Rönström et al. noted that the number of bacteria increased over a period of four hours. In contrast, ultrastructural investigations of early plaque have demonstrated bacterial colonization only within the first two hours of plaque development in a few samples obtained on a smooth surface and in most samples on a rough surface. However, microorganisms have been found regularly after four hours of plaque accumulation in subjects with healthy gingiva. The aim of the present investigation was to determine the earliest occurrence of bacterial colonization in situ and to observe the pattern of the initial formation of human dental plaque.

Adult↗
PubMed1993

Oral health status of a group of elderly Canadian Inuit (Eskimo).

Fifty-four Inuit elders, representing 90% of the individuals 60 yr of age and older in three communities in the Keewatin region of the Canadian Northwest Territories, were examined for dental caries, periodontal disease, levels of edentulism, and the fit and quality of denture prostheses. These elders had a mean of 2.8 +/- 3.5 decayed teeth and a DMFT of 26 +/- 13 which reflected significant tooth loss. The Root Caries Index for subjects with gingival recession was 19%. Periodontal pocket assessments revealed that 86% of the individuals examined had CPITN readings of either 3 or 4. Over one third of the elders were totally edentulous, most of them female. Only 47% of these individuals wore complete dentures. Denture fit assessment revealed that 36% of the complete maxillary dentures and 42% of the complete mandibular dentures fit poorly. The overall oral health findings for these Inuit elders differed from those found in other older populations; however, the present findings may be the norm for a population undergoing a cultural transition.

Aged↗
PubMed1993

Medical and dental status of a culture in transition, the case of the Inuit elderly of Canada.

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.

Acculturation↗
PubMed1993

Long-term effects of Meridol and chlorhexidine mouthrinses on plaque, gingivitis, staining, and bacterial vitality.

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.

Adult↗
PubMed1993

Vital fluorescence: a new measure of periodontal treatment effect.

The purpose of the current study was to determine, by means of a fluorescence test, the ratio between vital and dead bacteria in dental plaque before and two weeks following professional dental prophylaxis. A solution of fluoresceindiacetate (FDA) and ethidium bromide (EB) in normal saline was applied to plaque samples from 82 healthy adults both prior to and 14 days following professional prophylaxis. Living microorganisms were colored green by the FDA while the EB introduced a red color into the nucleic acids of dead cells. The relationships between the vital fluorescence scores and standard clinical measures, plaque index (PlI) and gingival index (GI) were analyzed. Two weeks following professional prophylaxis, a significant decrease was observed in the PlI scores (0.9 +/- 0.4, Day 0; 0.6 +/- 0.3, Day 14, p < 0.001) and the GI scores (1.1 +/- 0.2, Day 0; 0.7 +/- 0.3, Day 14, p < 0.001), while there was a statistically significant increase in the vitality of the dental plaque (74 per cent +/- 9, Day 0; 78 per cent +/- 7, Day 14, p < 0.001). The vital fluorescence (VF) technique may provide an additional explanation of periodontal treatment effect.

Adult↗
PubMed1992

Efficacy of Listerine, Meridol and chlorhexidine mouthrinses as supplements to regular tooth cleaning measures.

The anti-plaque, anti-gingivitis and anti-microbial efficacies of a phenolic compound (Listerine) and 2 different amine/stannous fluoride mouthwashes (Meridol I, II) were compared when these solutions were used in addition to usual tooth cleaning. A placebo preparation was utilized as a negative control and a chlorhexidine solution as a positive control in this double-blind study. After professional tooth cleaning, 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.

Adult↗
PubMed1992

Influence of oral hygiene on elastase concentration of gingival crevicular fluid.

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 elastase 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.

Adult↗
PubMed1992

Relationship between bacterial counts, microbial vitality and the accumulation of supragingival dental plaque in humans.

Comparisons between plaque index (PlI) 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 PlI 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 PlI was recorded on the vestibular surface of all first premolars as local PlI: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 forming units of 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.

Adolescent↗
PubMed1990

Efficacy of Listerine, Meridol and chlorhexidine mouthrinses on plaque, gingivitis and plaque bacteria vitality.

The experimental gingivitis model was used to compare the anti-plaque, anti-gingivitis and anti-microbial efficacies of a phenolic compound (Listerine) and an amine/stannous fluoride mouthwash (Meridol), using a placebo preparation as negative control and a chlorhexidine solution as positive control in a double-blind study. After professional toothcleaning, 36 volunteers performed optimal oral hygiene for a period of 2 weeks. They then ceased all oral hygiene procedures for 21 days during which they rinsed twice daily with 1 of the 4 mouthrinses. After 3 weeks of rinsing, plaque indices remained the lowest in the chlorhexidine group, while subjects using Listerine or Meridol harbored similar indices significantly lower than that of individuals rinsing with the placebo solution. Up to that time, the gingival index scores were equal in all groups except for the chlorhexidine group in which the values only amounted to half of these encountered in the other groups. The plaque vitality scores showed a bactericidal effect in vivo of chlorhexidine during the entire time of experimental gingivitis. In contrast, the data gave no evidence of an antibacterial effect in vivo of Listerine. The efficacy of Meridol to kill micro-organisms was similar to chlorhexidine during the early stages of plaque accumulation and, with time, became insignificant. This study has demonstrated that chlorhexidine was superior to Listerine and Meridol in its ability to maintain low plaque scores and gingival health during this 3-week period of no mechanical oral hygiene. Moreover, it was also shown that Meridol was as effective as Listerine in reducing plaque accumulation and, in contrast to Listerine, possessed a remarkable but transient antibacterial effect in vivo.

Adult↗
PubMed1989

Direct measurement of the bactericidal effect of chlorhexidine on human dental plaque.

The purpose of the present study was to determine by means of a fluorescence test the ratio between vital and dead bacteria in dental plaque before and after 0.1% chlorhexidine rinses. Plaque was stained by fluoresceindiacetate (FDA), which gave a green color to the living micro-organisms, and by ethidiumbromide (EB), which introduced a red color into the nucleic acids of the dead bacteria. 1-, 2- and 3-day-old undisturbed plaque harbored 80 to 85% living micro-organisms. 1 h after chlorhexidine use, this % was reduced to a plateau of 19 to 34% of vital bacteria present in the sampled plaque. Between 6 and 8 h later, this % rose towards its original value. This study has shown that FDA/EB staining provides a method for direct measurement of bacteria vitality in dental plaque and, as such, can be of great value for testing the efficacy of various antiplaque agents.

Adult↗
PubMed1989

[Periodontal disease and its treatment].

A well known development of the chronic periodontal disease is reviewed. However, the histological picture of a gingiva varies at a much lower speed than its clinical picture, and slower than previously described. In presence of periodontitis there may exit a zone of reversible disease of about 2 mm, which give the possibility of obtaining a re-attachment of unknown magnitude. A new connective tissue attachment (on top of the re-attachment) seems only possible if the periodontal ligament cells are allowed to proliferate coronally.

Dental Plaque↗
PubMed1989

[Healthy periodontal tissue, periodontitis and its cure].

A well known development of the chronic periodontal disease is reviewed. However, the histological picture of gingiva varies at a much lower speed than its clinical picture, and slower than previously described. In presence of periodontitis there may exist a zone of reversible disease of about 2 mm, which gives the possibility of obtaining a re-attachment of unknown magnitude. A new connective tissue attachment (on top of the re-attachment) seems only possible if the periodontal ligament cells are allowed to proliferate coronally.

Humans↗