Search Results - (Author, Cooperation:M. Timmerman)

2013-11-29

Nature Publishing Group (NPG)

0028-0836

1476-4687

Biology

Chemistry and Pharmacology

Medicine

Natural Sciences in General

Physics

1-Phosphatidylinositol 4-Kinase/*antagonists & ; inhibitors/chemistry/genetics/metabolism ; Adenosine Triphosphate/metabolism ; Animals ; Binding Sites ; Cytokinesis/drug effects ; Drug Resistance/drug effects/genetics ; Fatty Acids/metabolism ; Female ; Hepatocytes/parasitology ; Humans ; Imidazoles/metabolism/pharmacology ; Life Cycle Stages/drug effects ; Macaca mulatta ; Malaria/*drug therapy/*parasitology ; Male ; Models, Biological ; Models, Molecular ; Phosphatidylinositol Phosphates/metabolism ; Plasmodium/classification/*drug effects/*enzymology/growth & development ; Pyrazoles/metabolism/pharmacology ; Quinoxalines/metabolism/pharmacology ; Reproducibility of Results ; Schizonts/cytology/drug effects ; rab GTP-Binding Proteins/genetics/metabolism

1600-051X

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Background, aims: In order to investigate the rôle of various putative clinical and microbiological risk markers, a longitudinal study was initiated in a young population deprived of regular dental care. In 1987 all inhabitants in the age range 15–25 years living in a village with approximately 2000 inhabitants at a tea estate on Western Java, Indonesia, were examined clinically and microbiologically. In total, 167 subjects of the original group of 255 adolescents were re-examined in 1994. The material presented in this paper describes the clinical periodontal condition at baseline (1987) and at follow-up (1994), 7 years later. Furthermore, the relationship between progression of the disease and baseline clinical and microbiological data was assessed.Methods: Plaque index (PI), bleeding on probing (BOP), pocket depth (PD), and attachment loss (AL) were scored at the approximal surfaces of the vestibular aspects of all teeth. The number of approximal surfaces of the Ramfjord teeth showing subgingival calculus was recorded. At baseline, the dorsum of the tongue, the buccal gingiva in the upper jaw, the saliva and the deepest bleeding pocket without clinical loss of attachment were sampled for microbiological examination with phase contrast microscopy and indirect immunofluorescence.Results: Mean values at baseline and at follow-up were PI: 1.01 and 1.15, BOP: 0.80 and 1.16, PD 3.26 mm and 3.32 mm, AL: 0.33 mm and 0.73 mm, respectively. All parameters except PD showed a statistically significant increase over the 7-year period. The prevalence of the studied bacteria irrespective of the sample site was: A. actinomycetemcomitans 53%, P. gingivalis 88%, P. intermedia 100%, spirochetes 89% and motile micro-organisms 100%. At the full mouth level, logistic regression showed significant odds ratios for progressive disease with age (1.15), subgingival calculus (1.20) and subgingival presence of A. actinomycetemcomitans (4.61). Presence of any of the selected micro-organisms on the mucous membranes was not related with progressive disease. In order to study local factors to explain local disease activity, each subject was characterized using the sampled pocket, which was the deepest bleeding pocket without LA at baseline, as a single response site per patient. In this constrained design, the main statistical factors associated with progressive disease were presence of motile micro-organisms and the plaque score.Conclusions: This study identified 3 main risk markers for disease progression at the full mouth level: age, amount of subgingival calculus and subgingival presence of A. actinomycetemcomitans.

Electronic Resource

1600-051X

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Abstract. The present study primarily aimed at investigating the oral microbiota in smokers and non-smokers with established gingivitis and monitoring its composition during experimental gingivitis. Secondly, it aimed at examining whether the composition of the microbiota is associated with different levels of gingival inflammation during this experimental gingivitis trial. For this purpose, 25 non-dental university students with gingivitis were recruited. 11 subjects were smokers and 14 were non-smokers. After achieving gingival health, they entered a 14-day experimental gingivitis trial. Plaque and bleeding were assessed before entering into the study (intake), at day 0. day 5 and at day 14 of the experiment. Microbiological samples from mucosal sites and dental plaque (taken at intake, day 0, and day 14) were analysed for the presence of Actinomyces species. Actinobacillus actinomycetemcomitans, Bacteroides forsythus, Campylobacter rectus, Fusobacterium nucleatum, Peptostreptococcus micros. Porphyromonas gingivalis, Prevotella intermedia and Streptococcus species. At day 14 of the experimental period, the level of plaque formation was not different between smokers and nonsmokers, but bleeding scores were lower in smokers than in non-smokers (15% and 30%) respectively, p= 0.01). The change from natural gingivitis to a state of gingival health and a subsequent change from gingival health to experimentally induced gingivitis was accompanied by quantitative alterations in the cultivable microbiota in both groups. Changes were most prominent in the transition from gingival health to experimental gingivitis and were found in dental plaque for Actinomyces species, C. rectus, F. nucleatum, and P. intermedia. Within the group of non-smokers, a distinction was made between subjects with a‘weak’or 'strong’inflammatory response. No relationship with a single bacterial species could be established which would likely explain the differences in levels of inflammation. It is concluded that differences in response to experimental gingivitis are not caused by major differences in the composition of the oral microbiota.

Electronic Resource

1600-051X

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Abstract. The purpose of the present study was to establish in vitro the inhibiting effect of a herbal extract mixture on a selected number of micro-organisms and to test in vivo the effect of a mouthwash containing 6.3 mg/ml herbal extract mixture on plaque and gingivitis as compared to a minus active control mouthrinse. The herbal extract was a mixture of: Juniperus communis (juniper), Urtica dioca (nettle), Achillaea millefolium (yarrow); 1:1:1. In the study, in-vitro, the effect of pure herbal extract mixture on acid production of Streptococcus mutans was tested and the minimum inhibitory concentrations (MIC) of the following micro-organisms were tested: Streptococcus mutans, Streptococcus mitis, Actynomyces viscosus, Actynomyces naeslundii, Actinobacillus actinomycetemcomitans, Prevotella intermedia, Campylobacter rectus, Fusobacterium nucleatum, Veillonella parvula. The MIC-values for A. viscosus and P. gingivalis were 100 mg/ml. The MIC-values for A. naeslundii and A. actinomycetemcomitans were considerably lower (10 mg/ml). S. mitis was the most susceptible of the tested organisms to the extract with a MIC value of 1 mg/ml. S. mutans, C. rectus, V. parvula, and F. nucleatum were not influenced by the extracts. No inhibitory effect of the 6.3 mg/ml herbal extract mixture was observed on the acid production of S. mutans. For the study in-vivo, 45 volunteers were selected on the basis of having moderate gingival inflammation. As efficacy parameters the plaque index, modified gingival index and angulated bleeding index were assessed. The subjects were randomly divided among 3 experimental groups (2× test and 1‘minus active’control). The participants were requested to rinse with 10 ml of mouthwash twice a day for a period of three months. After 6 weeks and 3 months, the same clinical indices as at baseline were recorded. The results show no difference between the two test groups and the control group. In conclusion, the results of the present study have shown that the mixture of the 3 herbal extracts, Juniperus communis, Urtica dioca and Achillaea millefolium when used in a mouthrinse has no effect on plaque growth and gingival health.

Electronic Resource

1600-051X

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Abstract. This survey investigated the association between the efficacy of plaque removal and toothbrushing forces during a normal brushing regime. The 94 subjects participating in this study were requested not to brush 24 h prior to the experiment. Panellists brushed for 1 min with a manual toothbrush. Before and after brushing, plaque was assessed using the Turesky modification of the Quigley & Hein plaque index. A second 1-min exercise of brushing was carried out to assess the toothbrushing force. The mean plaque reduction was 39%, with vestibular surfaces being cleaned most effective (69%) and the lingual surfaces the least (21%). The mean brushing force was 330 g. No correlation was observed between efficacy and brushing force (r=0.14, p=0.16). The relationship between pre- and post-brushing plaque was stronger (r=0.68, p〈0.001). Multiple regression analysis entering squared values of force as an independent variable into the equation, indicated that the relation between efficacy and force was not linear. A curve could be fitted to the plot (p=0.0004), demonstrating that up to a certain level of force, an increase of force is associated with an increase in efficacy (r=0.33, p〈0.01). Beyond this point, application of higher forces resulted in reduced efficacy (r=-0.49, p=0.03). As was calculated in this particular test this‘transition’level of force was 407.4 g. The absence of a correlation between brushing force and plaque removal efficacy suggests that in a‘user model’brushing situation, other factors than brushing force are of major influence on the amount of plaque removed.

Electronic Resource

1600-051X

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Objective: The aim of this study was to determine the microbial atmospheric contamination during initial periodontal treatment using a piezoelectric ultrasonic scaler in combination with either high-volume evacuation (HVE) or conventional dental suction (CDS).Methods: The study included 17 treatment sessions, consisting of a 40-min episode of continuous plaque and calculus removal using an ultrasonic unit (EMS). The treatment sessions were carried out in six patients with generalized adult periodontitis and ranged from two to four sessions per patient according to their needs. The use of HVE and CDS was randomly assigned over the sessions within each patient. Before each treatment, the operating room was not used for 15 h. To measure baseline microbial air pollution two Petri dishes containing blood agar were exposed for 10 min to the air. At the start of each treatment session, two Petri dishes were exposed for 5 min at a distance of 40 cm from the mouth of the patients. After 20 min, this procedure was repeated. At a distance of 150 cm, two Petri dishes were exposed for 20 min followed by exposure of two new Petri dishes for the rest of the session. The plates were cultured aerobically and anaerobically for 3 and 7 days, respectively.Results: The mean colony forming units (CFU) before treatment never exceeded 0.6 colonies per plate. At 40 cm, the mean CFU, when considering a period of 40 min, was 8.0 for HVE and 17.0 for CDS. The mean CFU at 150 cm during this period was 8.1 with HVE and 10.3 with the CDS. With reference to the Air Microbial Index the operatory atmosphere was considered to be in a good condition during 40 min of continuous use of the ultrasonic scaler in combination with both HVE and CDS.Conclusion: Within the restrictions of this study, only limited atmospheric microbial contamination is produced when using a piezoelectric ultrasonic scaler.

Electronic Resource

1600-051X

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Abstract Background, aims: The aim of this double-blind, parallel study was to evaluate the adjunctive effects of systemically administered amoxicillin and metronidazole in a group of adult periodontitis patients who also received supra- and subgingival debridement.Methods: 49 patients with a diagnosis of generalised severe periodontitis participated in the study. Random assignment resulted in 26 patients in the placebo (P) group with a mean age of 40 years and 23 patients in the test (T) group which had a mean age of 45 years. Clinical measurements and microbiological assessments were taken at baseline and 3 months after completion of initial periodontal therapy with additional placebo or antibiotic treatment. Patients received coded study medication of either 375 mg amoxicillin in combination with 250 mg metronidazole or identical placebo tablets, every 8 hours for the following 7 days.Results: At baseline, no statistically significant differences between groups were found for any of the clinical parameters. Except for the plaque, there was a significantly larger change in the bleeding, probing pocket depth (PPD) and clinical attachment level (CAL) in the T-group as compared to the P-group after therapy. The greatest reduction in PPD was found at sites with initial PPD of 〈inlineGraphic alt="geqslant R: gt-or-equal, slanted" extraInfo="nonStandardEntity" href="urn:x-wiley:03036979:JCPE280402:ges" location="ges.gif"/〉7 mm, 2.5 mm in the P-group and 3.2 mm in the T-group. The improvement in CAL was most pronounced in the PPD category 〈inlineGraphic alt="geqslant R: gt-or-equal, slanted" extraInfo="nonStandardEntity" href="urn:x-wiley:03036979:JCPE280402:ges" location="ges.gif"/〉7 mm and amounted to 1.5 mm and 2.0 mm in the P- and T-groups, respectively. No significant decrease was found in the number of patients positive for any of the test species in the P-group. The number of patients positive for Porphyromonas gingivalis, Bacteroides forsythus and Prevotella intermedia in the T-group showed a significant decrease. After therapy there was a significant difference between the P- and the T- group in the remaining number of patients positive for P. gingivalis, B. forsythus and Peptostreptococcus micros. 4 subgroups were created on the basis of the initial microbiological status for P. gingivalis positive (Pg-pos) and negative patients (Pg-neg) in the P- and the T-groups. The difference in reduction of PPD between Pg-pos and Pg-neg patients was particularly evident with respect to the changes in % of sites with a probing pocket depth 〈inlineGraphic alt="geqslant R: gt-or-equal, slanted" extraInfo="nonStandardEntity" href="urn:x-wiley:03036979:JCPE280402:ges" location="ges.gif"/〉5 mm. This % decreased from 45% at baseline to 23% after treatment in the Pg-pos placebo subgroup and decreased from 46% to 11% in the Pg-pos test subgroup (p〈inlineGraphic alt="leqslant R: less-than-or-eq, slant" extraInfo="nonStandardEntity" href="urn:x-wiley:03036979:JCPE280402:les" location="les.gif"/〉0.005). In contrast, the changes in the proportions of sites with a probing pocket depth 〈inlineGraphic alt="geqslant R: gt-or-equal, slanted" extraInfo="nonStandardEntity" href="urn:x-wiley:03036979:JCPE280402:ges" location="ges.gif"/〉5 mm in the Pg-neg placebo and Pg-neg test subgroup were similar, from 43% at baseline to 18% after treatment versus 40% to 12%, respectively.Conclusions: This study has shown that systemic usage of metronidazole and amoxicillin, when used in conjunction with initial periodontal treatment in adult periodontitis patients, achieves significantly better clinical and microbiological results than initial periodontal treatment alone. Moreover, this research suggests that especially patients diagnosed with P. gingivalis benefit from antibiotic treatment.

Electronic Resource

1600-051X

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Background/aims: In an Indonesian population deprived of regular dental care, the experienced progression of disease between baseline (1987) and follow-up (1994) was investigated in relation to the composition of the subgingival microbiota at follow-up. At baseline the age ranged from 15 to 25 years. Clinical and microbiological evaluation was completed in 158 of the 167 subjects available at follow-up.Methods: Plaque index (PI), pocket depth (PD), bleeding on probing (BOP), and attachment loss (AL) were scored at the approximal surfaces of all teeth and subgingival calculus on the approximal surfaces of the Ramfjord teeth only (number of sites with subgingival calculus: NSC). A pooled sample of the deepest pocket in each quadrant was evaluated using microbiological culture techniques.Results: At baseline the mean values of the clinical parameters were AL=0.35 mm, PI=1.01, BOP=0.80 PD=3.25 mm and NSC=6.04 and at follow-up AL=0.75 mm, PI=1.16, BOP=1.19, PD=3.34 mm and NSC=5.85. All parameters except PD and NSC showed a statistically significant increase. At follow-up the prevalence of Actinobacillus actinomycetemcomitans was 40%, of Porphyromonas gingivalis 67%, of Prevotella intermedia 66%, of Fusobacterium nucleatum 79%, of Bacteroides forsythus 16%, of Campylobacter rectus 4%, and of P. micros 6%. No differences in clinical parameters were found between groups with or without these micro-organisms. In 129 subjects AL of 〈inlineGraphic alt="geqslant R: gt-or-equal, slanted" extraInfo="nonStandardEntity" href="urn:x-wiley:03036979:JCPE280703:ges" location="ges.gif"/〉2 mm at 〈inlineGraphic alt="geqslant R: gt-or-equal, slanted" extraInfo="nonStandardEntity" href="urn:x-wiley:03036979:JCPE280703:ges" location="ges.gif"/〉1 site was found. Logistic regression showed three significant odds-ratio’s for experienced progressive periodontitis: Plaque index (12.2), gender (3.4) and Actinobacillus actinomycetemcomitans (2.9).Conclusions: The results of this retrospective study suggest that plaque is the most important parameter related to experienced disease progression, and that the presence of A. actinomycetemcomitans may be associated with increased chance of disease progression.

Electronic Resource

1600-051X

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Aim: The occurrence of Prevotella intermedia (Pi) and Prevotella nigrescens (Pn) in relation to natural gingivitis, gingival health and 14-day experimental gingivitis was investigated in 25 non-dental students.〈section xml:id="abs1-2"〉〈title type="main"〉Materials and Methods:Samples were taken from the dorsum of the tongue, the tonsils (or tonsillar area), and the supra- and subgingival plaque.Results: The microbiological results show that 73% of the samples were positive for the bacterial species presumed to be Pi and/or Pn. In natural gingivitis, gingival health and in experimental gingivitis 25, 23 and 25 subjects were found to be positive for Pi and/or Pn, respectively. The results of the 889 isolates that were succesfully purified and differentiated, show that almost all subjects were colonized with Pn whereas approximately half of the study population harboured Pi. These 2 species were isolated from both dental plaque and mucosal sites and were found to colonize the oral cavity simultaneously.Conclusion: In natural gingivitis, at the start and after 14 days of experimental gingivitis, Pn was the predominant micro-organism.

Electronic Resource

1600-051X

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Abstract. The purpose of the present study was to compare the bleeding tendency as elicited by probing the marginal gingiva (BOMP) and probing to the bottom of the pocket (BOPP) in smokers and non-smokers in natural gingivitis and during experimental gingivitis, 11 smokers (sm) and 14 non-smokers (nsm) were recruited. When they had less than 20% approximal bleeding sites, they entered a 14-day trial period of experimental gingivitis'. Subjects returned 30 days later, after resuming normal oral hygiene procedures, for a final gingival assessment. A split-mouth design was chosen using 2 contra-lateral quadrants for each index (being either BOMP or BOPP). A consistently higher bleeding score of approximately 10% was observed by probing to the bottom of the pocket. At day 14 with both indices, a significant difference between smokers and non-smokers was detected (BOMP: sm=15%, nsm = 30%; BOPP: sm = 27%, nsm=44%). The increment between gingival health and experimental gingivitis was significantly higher in non-smokers than in smokers but comparable for both indices (BOMP: sm=8%, nsm = 23%; BOPP: sm=9%, nsm=26%). Probing to the bottom of the pocket results in significantly more bleeding in gingival health and gingivitis as compared to probing of the marginal gingiva. This shows that evaluation of the gingival condition with BOMP, the method of choice with respect to gingivitis, can be used as a parameter for inflammation when comparing smokers and nonsmokers. The suppressed inflammatory response to plaque accumulation, as observed in smokers, indicates that they should be identified as a separate group when they participate as panellists in (experimentally induced) gingivitis

Electronic Resource

1600-051X

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Abstract. The aims of the present study were: (1) to establish the incidence of gingival abrasion as a result of toothbrushing. using a manual and electric toothbrush: (2) to establish the influence of filament end-rounding on the incidence of gingival abrasion and the efficacy of toothbrushing: (3) to assess whether the speed of the electric brush has a feedback-effect on the brushing force used and to correlate the incidence of gingival abrasion with force. 2 experiments were earned out. In the first experiment, 50 subjects brushed for 3 weeks every other day with either a manual (Butler 411) or an electric toothbrush (Braun/Oral-B Ultra Plaque Remover-D9). All received brief instructions and were asked to abstain from oral hygiene 24 hrs before their appointment. After disclosing the teeth and gums with Mira-2-Tone solution, plaque and gingival abrasion were assessed. Next, the panellists brushed in a random split-mouth order. After brushing and a second disclosing, plaque and abrasion were re-assessed. The results showed that the incidence of gingival abrasion was comparable for the manual and the D9. Using a similar design as in experiment no. 1, in experiment no. 2 a new group of 47 subjects brushed for 3 weeks alternating between the Braun/Oral-B Plaque Reniover-D7 and D9. At the appointment, the subjects first brushed in a split-mouth order with the D9 with 2 different types of endrounding. Plaque and abrasion were assessed. Immediately following this brushing exercise, the subjects re-brushed with the D7 (2800 rot/min) and the D9 (3600 rot/min) during which brushing force was measured. The results of this experiment showed that end-rounding has no effect on plaque removal but does effect the incidence of gingival abrasion. Brushing force is not influenced by the speed of the brushhead and no correlation with the incidence of gingival abrasion was observed. In conclusion, the results of this study show that gingival abrasion is not influenced by brushing force, but is affected by filament endrounding.

Electronic Resource

1600-051X

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Background: Previous studies have shown that using an oxidising agent in addition to chlorhexidine reduces staining.〈section xml:id="abs1-2"〉〈title type="main"〉Aim:The purpose of the present study was to investigate whether, compared to chlorhexidine alone, the use of an oxidising mouthrinse as an adjunct to chlorhexidine is efficacious in reducing stain, plaque and gingivitis.Method: This study had a single-blind, 2-group parallel design, including a 14-day experimental non-brushing period during which 1 group (n=14) used chlorhexidine alone (CHX) (chlorhexidine mouthrinse, 0.12% Oral-B® laboratories, Ireland), and the other (n=14) used chlorhexidine in combination with an oxidising agent (sodiumperborate-monohydrate-Bocasan®, Oral-B laboratories, Ireland). Patients were randomly assigned to either group. All participants received a scaling and polishing before the start of the trial. No oral hygiene instructions were given. Since, at the start of the experiment, all stain and plaque were removed, only the gingival condition was evaluated at baseline by means of bleeding on marginal probing. The examination after 14 days of rinsing included the evaluation of plaque, bleeding on marginal probing and stain (GMSI: gingival modification of the stain index).Results: The results showed at day 14, a significant difference between the 2 groups for plaque (CHX: 0.18, CHX+PER: 0.08, p=0.03) and gingival bleeding (CHX: 0.38, CHX+PER: 0.21, p〈0.001). The proportion of stained surfaces was less in the CHX+PER group (28%), than in the chlorhexidine group (48%) (p=0.04).Conclusions: In conclusion, the adjunctive use of an oxidising agent peroxyborate to chlorhexidine, proved to be superior to chlorhexidine alone with regard to the inhibition of plaque and development of gingivitis. In addition, the proportion of stained surfaces was significantly less when adding the oxidising mouthrinse to chlorhexidine.

Electronic Resource

1600-0765

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Jresons who smoke display a less pronounced increase of gingival bleeding in the exjreimental gingivitis model as compared with non-smokers. The aim of the present study was to investigate whether this could partly be explained by differences in levels of parotid total secretory IgA (S-IgA) or parotid S-IgA reactive with selected oral microorganisms. Parotid saliva samples were obtained from 11 smoking and 14 non-smoking volunteers, at baseline, after 5 and 14 days of full mouth exjreimental gingivitis. Output levels of total S-IgA and of specific S-IgA reactive with cell extracts from Actinobacillus actinomycetemcomitans, Actinomyces naeslundii, Campylobacter rectus, Fusobacterium nucleatum, Porphyromonas gingivalis, Prevotella intermedia, Prevotella nigrescens, Peptostreptococcus micros, Streptococcus gordonii and Streptococcus mutans were determined in the samples by means of ELISA. Smokers and non-smokers were found to have similar output levels (μg/min) of total S-IgA, and the values did not significantly change during the exjreimental gingivitis trial. Parotid salivary outputs (units/min) of the bacteria-specific S-IgA at baseline and at days 5 and 14, were not different between smokers and non-smokers; no changes were observed during the exjreimental gingivitis trial. The present observations indicate that total S-IgA and bacteria-specific S-IgA in saliva are not main factors that can explain the less pronounced increase of gingival bleeding in the exjreimental gingivitis model in smokers as compared with non-smokers.

Electronic Resource

1600-0765

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

The present study was designed to evaluate if different periods of supervised oral hygiene prior to the experimental gingivitis trial have an effect on the amount of inflammation which develops in the ‘toothshield’ model. Two groups were compared. One group (Group A) was supervised over a 5-month period before experimental gingivitis. Six months later Group A participated in a second trial, this time receiving only a 1-month pretrial. A second group (Group B) which served as a control was supervised over a pre-trial period of 1-month prior to the start of the experimental gingivitis phase. During the pre-trial period all subjects undertook a regime of vigorous oral hygiene which included polishing of the test quadrant in the upper jaw and supervised subgingival brushing, interdental taping or the use of toothpicks. The presence of plaque and bleeding were assessed. Following the pre-trial period all plaque control measures in the experimental area were prevented during oral hygiene periods by the temporary placement of soft, loosely fitting vinyl toothshield guard. During this period they accumulated plaque rapidly and developed a generalized gingivitis. The results of this study indicate that, irrespective of the length of the pre-trial period, subjects by group develop a comparable mean level of plaque and gingival bleeding. However, the extent to which gingivitis develops differs among individuals and was for a number of subjects not consistent. Therefore, in designing an experimental gingivitis trial care should be taken to include a sufficient number of subjects to account for individual variation.

Electronic Resource

1600-0765

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Sulcular bleeding after stimulation with a periodontal probe has been associated with the presence of an inflammatory lesion in the gingiva. The objective of this study was to evaluate the effect of the placement of the probe in relation to the tooth surface, and the effect of standardising the probing pressure on the intra- and inter-examiner reproducibility of the gingival bleeding when using a well-defined bleeding index. Four different variations were defined: parallel bleeding index (ParBI): when the probe is run along the marginal gingiva it is held parallel to the tooth surface. Angulated bleeding index (AngBI): the probe is held at an angle of approximately 60° to the longitudinal axis of the tooth and in contact with the sulcular epithelium. Controlled force parallel bleeding index (CF-ParBI)/controlled force angulated bleeding index (CF-AngBI): the same procedure as described for the ParBI and AngBI is followed, but instead of a conventional (WHO-ASH/Dentsply(r)) probe an adjustable force probe (Brodontic(r)-ASH/dentsply), adjusted to 0.25 N is used. The results show that the agreement both within and between clinicians could hardly be rated as ‘fair’ on a site basis. Approximately one in every three sites was given a different assessment on the second examination. This might have been the consequence of the repeat examination. Agreement on a quadrant basis was slightly better. Furthermore, the direction of the probing influences the number of provoked bleeding sites. Angulation of the probe produces consistently less bleeding compared with parallel placement of the probe.

Electronic Resource

1365-3121

Blackwell Publishing Journal Backfiles 1879-2005

Geosciences

207Pb/206Pb ages are presented for detrital zircons (Laser Ablation Microprobe ICP-MS) and whole-rock Nd isotopic determinations (TIMS) from samples of Neoarchean and Palaeoproterozoic metasedimentary rocks from the Umba granulite terrane and the Keivy domain of the Central Kola composite terrane, Kola Peninsula, north-western Russia. Three are samples of rocks from the Umba granulite terrane that were deposited ≈ 2.20–1.90 Ga; they contain Archaean detritus, much of it older than 3.0 Gyr, as well as abundant 2.20–1.95-Gyr-old material. Deposition may have occurred on the margin of an Archaean craton with an exposed Palaeoproterozoic magmatic arc source, possibly during orogenesis. Two samples from the Keivy domain have remarkably similar, dominantly Archaean detrital zircon age spectra. One was deposited pre-2.4 Ga, whereas the other was probably deposited post-2.01 Ga. Both had similar sources, compatible with the proximal country rocks, and possible shallow-water (?) cratonic margin depositional settings.

Electronic Resource

1600-051X

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Aim: The purpose of the present study was to compare 2 indices, i.e., the Eastman interdental bleeding (EIB) index and the bleeding on marginal probing (BOMP) index. The comparison was made (a) in terms of the degree of bleeding provoked and the relationship with plaque in natural gingivitis and (b) for the ability of these 2 methods to detect differences between the development of experimental gingivitis in a control group and a group in which the development of gingival inflammation was suppressed by treatment. For the present studies, subjects were selected without interdental recession of the gingival tissues.Methods experiment 1: In this experiment, 43 subjects having established moderate gingivitis were assessed using a random splitmouth design (1st and 3rd/2nd and 4th quadrant). Plaque was scored on all approximal sites after which the BOMP index was assessed in one half of the mouth and the EIB index in the other.Results experiment 1: The BOMP index showed a bleeding score of 84% and the EIB index of 87%. The significant correlation between plaque and gingival bleeding for the BOMP index (0.55) was higher than for the EIB index (0.44).Methods experiment 2: For this experiment, 25 subjects participated in an experimental gingivitis trial of the lower jaw. At baseline, first the BOMP index and immediately thereafter the EIB index were assessed at all approximal sites. Experimental gingivitis (EG) was carried out in one randomly assigned quadrant and as a treatment modality only floss was used in the other (FL). Results experiment 2: In the EG quadrant, the BOMP index increased to 69% and the EIB index to 73%. Both indices showed a significant correlation with plaque; 0.60 and 0.64 respectively. In the FL quadrant, the BOMP index increased to 38% and the EIB index to 30%. No significant correlation between both gingivitis indices and the amount of plaque was present in the FL quadrant. Conclusion: The ability of the BOMP index and the EIB index to assess the level gingival inflammation appears to be comparable.

Electronic Resource

1600-051X

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Background: When the subgingival presence of periodontal pathogens is studied in groups of patients or populations, mostly a number of the deepest sites is sampled. The mean clinical parameters of these deep sites are also frequently used as a the descriptor of the clinical situation of these subjects. It can be questioned, whether these 4 deep sites are capable of predicting a full-mouth situation.Aim: The purpose of the present retrospective study was to investigate to what extent the experienced progression of periodontitis as measured in the deepest approximal pocket in each quadrant reflects the disease progression at the approximal sites on a full-mouth level.Methods: A data set of a 7-year longitudinal study of 158 young subjects (69 male, 89 female, 15–25 years of age at baseline) was used. Clinical assessments included plaque index (PI), pocket depth (PD) and attachment loss (AL) at baseline (1987) and follow-up (1994). Measurements were made at the approximal surfaces of all teeth. The deepest pocket in each quadrant was determined at follow-up. Changes of the clinical parameters between baseline and follow-up were calculated both as full-mouth mean scores as well as for these 4 deepest sites. A regression analysis was used to evaluate the relationship between full-mouth score and the 4 test sites.Results: For disease progression between baseline and follow-up, significant correlation coefficients were observed between the 4-site and full-mouth mean changes (PD: 0.80, AL: 0.70, PI: 0.77). Regression coefficients were 0.51 for PD, 0.35 for AL and 0.55 for PI. The precision of the estimate for the full-mouth mean, as predicted by the 4-site mean, is determined by the residual standard deviation. This was for PD 0.31 mm, for AL 0.31 mm and for PI 0.29. Compared to the between-patient standard deviation of the full-mouth means, the residual standard deviations were high.Conclusion: In the present population, a reasonable to good correlation between full-mouth and 4-sites data was observed. However, the high residual standard deviation in the regression analysis illustrates the inaccuracy for the 4-sites data when used as a descriptive for changes in the periodontal condition on a full-mouth level. Data evaluating progression of periodontitis based on a limited number of diseased sites should be interpreted cautiously.

Electronic Resource

1600-051X

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Abstract. In this study, the prevalence and serotype distribution of Porphyromonas gingivalis in an Indonesian population (n=158) is described. The relationship between subgingival P. gingivalis and periodontal attachment loss was investigated. The serotype distribution and periodontal parameters were studied. Serotyping was also used to study person-to-person transmission between siblings and between spouses. Approximately 50% of the subjects had periodontal attachment loss ≥3 mm at 1 or more recorded sites. The population was divided into 2 subgroups based on the presence or absence of P. gingivalis. No differences in plaque index, pocket depth, clinical attachment loss, bleeding upon probing, % of sites with ≥3 mm clinical attachment loss and % of sites with probing pocket depth 〉5 mm, were observed between both sub-populations. All known 6 capsular serotypes were found in the study population, with the exception of the K1 type. Detection of 1 of the known P. gingivalis serotypes was not related with the amount of clinical attachment loss. In 3 out of 29 sibships with more than one member positive for P. gingivalis, an identical P. gingivalis serotype was found. None of the 15 couples in the study shared an identical P. gingivalis serotype, indicating that transmission is probably not a common phenomenon in this population.

Electronic Resource

0270-3092

Elsevier Journal Backfiles on ScienceDirect 1907 - 2002

Medicine

Psychology

Electronic Resource