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Biomedical subjects

M Brecx

Publications and source records attributed to M Brecx.

At least 19 recordsLinked to original sources
PubMed1997

Medical status, functional status and drug utilization patterns of a population of older dental patients in Winnipeg, Manitoba.

Despite the wealth of epidemiological studies that have evaluated the oral health status of older Canadian dental patients, comprehensive epidemiologic data on their medical status, functional status and drug utilization patterns are deficient. To address this deficiency, the authors evaluated 170 older dental patients (> or = 65 years, mean = 82 years, sex distribution = 77.1 per cent female, 22.9 per cent male) in Winnipeg, Manitoba. Study participants averaged five medical conditions per person (males = females). The most prevalent conditions were vision deficits, cardiovascular disorders and orthopedic problems. Functional assessment of the Activities of Daily Living revealed that study participants were essentially independent. Within the study population, 90 per cent were taking at least one medication (mean = 2.8 drugs per person), most of which were analgesics, diuretics and gastrointestinal agents. Drug utilization rates were consistent with other studies that have evaluated prescribing patterns in community-dwelling older Canadian adults.

Activities of Daily Living↗
PubMed1996

Antibacterial effects of amalgams on mutans streptococci in an in vitro biofilm test procedure.

Conflicting data continue to be presented in the literature regarding the antibacterial potential of various amalgam alloy compositions. The aim of the present study was to compare the antibacterial effects of 4 different amalgam samples on mutans streptococci using two in vitro test procedures. Glass and bovine enamel served as negative controls. The first test, one commonly used, consisted of immersing freshly prepared disks of the six materials in culture broth inoculated with mutans streptococci. Optical density measurements of the broth served to evaluate bacterial growth. This was followed by a biofilm technique which provided more intimate contact between the bacteria and specimen surfaces. With the exception of one high-copper lathe-cut amalgam, the first test revealed no antibacterial potential of the samples whereas the second test with the biofilm design elucidated significant differences in antibacterial potential between the amalgam alloy compositions and the controls. The biofilm technique, used in an in vitro test procedure, reflects the conditions of the oral environment more accurately than conventional test designs.

Animals↗
PubMed1996

Vital fluorescence to assess in vitro and in vivo the antibacterial effects of amalgams.

The aim of the present study was to establish an alternative methodology for testing the antibacterial effects of different amalgams. The vitality of mutans streptococci grown in vitro on various amalgam surfaces was monitored with a vital fluorescence staining technique using fluorescein diacetate and ethidium bromide. The in vivo effect of amalgam-non-gamma 2 fillings on the vitality of dental plaque was assessed with the same method and compared with samples originating from enamel. The median in vitro vitality of mutans streptococci was estimated as 70% on glass, 50% on Amalcapnon-gamma 2 and Sybraloy, 20% on Amalcap F and 10% on Neo-Silbrin. In vivo plaque vitality on enamel varied from 60 to 70%. In contrast, plaque sampled from non-gamma 2-amalgam surfaces revealed significant reductions in vitality with a minimum value of 25% of one day old supragingival plaque. The vital fluorescence technique was shown as an easy and quick method to assess the bactericidal effect against biofilm bacteria of dental materials in vitro as well as in vivo.

Anti-Bacterial Agents↗
PubMed1995

Microbial generation time during the early phases of supragingival dental plaque formation.

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 x 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.

Adult↗
PubMed1995

Plaque bacteria counts and vitality during chlorhexidine, meridol and listerine mouthrinses.

The aim of this double-blind study was to enumerate the total number of living and dead bacteria on defined tooth areas during the application of antibacterial mouthrinses. After prophylaxis, 40 students refrained from all oral hygiene measures for 3 d, during which they rinsed with a phenolic compound (Listerine), an amine fluoride/stannous fluoride solution (Meridol), 0.2% chlorhexidine (CHX) or a control solution (0.02% quinine-hydrochloride). The plaque index (P1I) was recorded at the start and the end of the investigation. Total bacterial counts (BC) and colony-forming units (CFU) of 1d-, 2d- and 3d-old dentogingival plaque were determined. The plating efficiency (PE) was calculated as a percentage of CFU/BC and the portion of vital microflora estimated by a vital fluorescence technique (VF). All groups started with a P1I approximating 0.1. On day 3, the P1I values were 1.21 in the control group and 0.51, 0.37 and 0.14 after Listerine, Meridol and CHX use, respectively. A tremendous variation existed between the numbers of viable bacteria found per mm2 on the enamel surface and day 3 (CHX: 0.2; Meridol: 300; Listerine; 6x10(4); control: 2x10(6)), while higher total numbers of bacteria were concomitantly present (CHX and Meridol: 1-2x10(4); Listerine: 2x10(5); control: 2x10(6)). Both vitality parameters PE and VF reached 92% in the control group at day 3, but only 7% after CHX use. With Meridol and Listerine, the corresponding PE values were 3% and 43%, respectively, while the VF values reached 48% and 54%. The PII, BC, CFU and PE values of the CHX and the Meridol groups differed significantly from those of the control group. In contrast, Listerine showed no difference as compared to the control rinse. Due to the strong antibacterial action of CHX and Meridol during their use, almost only dead or non-proliferating bacteria were found on the tooth surfaces. Thus, only a thin plaque could develop. As a clinical consequence, both substances showed retardation of plaque development as reflected by significantly reduced plaque indices.

Adolescent↗
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↗