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Biomedical subjects

A J van Winkelhoff

Publications and source records attributed to A J van Winkelhoff.

At least 37 records · Page 2Linked to original sources
PubMed2001

Polymorphisms of the interleukin-1 gene family, oral microbial pathogens, and smoking in adult periodontitis.

Interleukin (IL)-1alpha, IL-1beta, and IL-1ra contribute to regulation of the inflammatory response in periodontal tissues. We aimed to investigate the distribution of polymorphisms in the IL-1 gene family among periodontitis patients and controls, taking into account smoking and microbiology as additional variables. Fifty-three non-smoking and 52 smoking patients with severe adult periodontitis and 53 controls were genotyped for bi-allelic IL-1A(-889), IL-1B(-3954), and a penta-allelic 86-bp VNTR IL-1RN gene polymorphisms. The presence of Porphyromonas gingivalis and Actinobacillus actinomycetemcomitans was established by culture techniques. We found a higher frequency of allele 2 carriage in IL-1A, IL-1B, and IL-1RN in periodontitis patients who were non-smokers and in whom P. gingivalis and A. actinomycetemcomitans could not be detected (42.1% vs. 11.3% in controls; P = 0.0068; OR 5.7, 95% CI: 1.6-19.8). Our results provide evidence that polymorphisms in genes of the IL-1 family are associated with severe adult periodontitis in the absence of other risk factors tested in this patient population.

Adult↗
PubMed2001

Smoking affects the subgingival microflora in periodontitis.

BACKGROUND: Tobacco smoking has been identified as one major risk factor for destructive periodontal disease. Scaling and root planing have been shown to be less effective in smokers with periodontitis. The aim of the present study was to compare the subgingival microbial flora of treated and untreated smokers and non-smokers. METHODS: Four independent adult patient groups with periodontitis were included in this investigation: 88 untreated smokers (U-S); 90 untreated non-smokers (U-NS); 119 treated non-smokers (T-NS); and 171 treated smokers (T-S). Clinical variables included cumulative plaque index (CPI), probing depth (PD), clinical attachment level (CAL), cumulative bleeding index (CBI), and cumulative suppuration index (CSI). Paper point samples from the deepest bleeding pocket in each quadrant of the dentition were analyzed for the presence and levels of 6 periodontal bacterial pathogens using anaerobic culture techniques. RESULTS: U-S showed a higher mean cumulative plaque index than U-NS (3.5 versus 2.7). Mean PD and mean CAL were higher in the T-S in comparison to the T-NS group (7.0 versus 6.6 mm and 5.6 versus 4.7 mm, respectively). Microbiological characteristics of U-S were a higher prevalence of Prevotella intermedia/nigrescens and higher mean levels of Peptostreptococcus micros (Pm) and Fusobacterium nucleatum (Fn). T-S patients were characterized by higher prevalence of Bacteroides forsythus (Bf), Pm, and Campylobacter rectus (Cr) and higher mean levels of Pm and Fn. The mean percentage of B. forsythus tended to be higher in the T-S group than in the T-NS group (6.9% versus 5.6%). The relative risk to be infected with Bf, Pm, and Cr was statistically higher in smokers (odds ratios: 1.9, 1.9, and 1.6, respectively). The chance to find > or =10% of Bf, Pm, and/or Fn was 3.3 higher in smokers when A. actinomycetemcomitans and P gingivalis were absent. Detection of > or =20% Pm/Fn in treated patients was strongly associated with smoking (odds ratio 13.8, P= 0.002). CONCLUSIONS: Smoking is a determining factor for the composition of the subgingival microflora in adult patients with periodontitis and may select for a specific cluster of periodontal pathogens, notably Bf, Pm, Fn, and Cr. On the basis of these observations, smoking, among other criteria, may be one parameter to use in deciding to treat refractory periodontitis in smokers with a systemic antibiotic therapy directed against smoking-associated periodontal bacteria.

Adult↗
PubMed2000

Early colonization of dental implants by putative periodontal pathogens in partially edentulous patients.

There is limited scientific information available on the early colonization of the peri-implant pockets in partially edentulous individuals. Knowledge about this process is one step in better understanding the etiology and pathogenesis of peri-implantitis. In this study, the early colonization of the peri-implant pockets by putative periodontal pathogens was studied in 20 partially edentulous individuals using anaerobic culture techniques. At baseline, the presence and levels of putative periodontal pathogens in the microflora of periodontal pockets and saliva were established. Immediately after loading of the titanium implants and after 6 and 12 months the presence and levels of selected putative periodontal pathogens were determined in periodontal and peri-implant pockets. A second aim was to detect bacterial contamination of the implant site and the inside of the implant. At baseline, the most frequently isolated species from the periodontal pockets were Fusobacterium nucleatum, Prevotella intermedia and Peptostreptococcus micros. Bacteroides forsythus, Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis were isolated from 9, 2 and 3 patients respectively. Six months after placing of the bridges, the majority of the implant sites had detectable levels of most periodontal bacterial species with the exception of A. actinomycetemcomitans which could not be isolated from any of the peri-implant samples during the experimental period, although 2 patients had this organism at baseline. In 2 patients with detectable subgingival P. gingivalis at baseline this species was found after 12 months in the peri-implant sites. One of these patients lost 2 implants which was associated with a high proportion of P. gingivalis in the peri-implant pockets. A second patient developed 2 fistulas around 2 implants at 8 months and this event was also associated with the presence of P. gingivalis. It is concluded that proper periodontal infection control before installment of dental implants in partially edentulous patients may prevent early bacterial complications.

Aged↗
PubMed2000

Antimicrobial resistance in the subgingival microflora in patients with adult periodontitis. A comparison between The Netherlands and Spain.

BACKGROUND: The widespread use of antibiotics for prophylaxis and treatment of bacterial infections has lead to the emergence of resistant human pathogens. Great differences have been documented between European countries in the use of systemic antibiotics. In parallel, significant differences in levels of resistant pathogens have been documented. AIM: To investigate whether differences in antibiotic use influence the level of antimicrobial resistance of the subgingival microflora of untreated patients with adult periodontitis in The Netherlands and Spain. METHOD: Blood agar plates containing breakpoint concentrations of penicillin, amoxicillin, amoxicillin and clavunalate, metronidazole, erythromycin, azithromycin, clindamycin and tetracycline were used to determine the proportion of bacteria from the subgingival plaque that was resistant to these antibiotics. In the Spanish patients, statistically significant higher mean levels of resistance were found for penicillin, amoxicillin, metronidazole, clindamycin and tetracycline. The mean number of different bacterial species growing on the selective plates was higher in the Spanish patients, as was the % of resistant strains of most periodontal pathogens. A striking difference was observed in the frequency of occurrence of tetracycline-resistant periodontal pathogens. In Spain, 5 patients had > or =3 tetracycline resistant periodontal pathogens, whereas this was not observed in any of the Dutch patients. CONCLUSIONS: The widespread use of antibiotics in Spain is reflected in the level of resistance of the subgingival microflora of adult patients with periodontitis.

Adult↗
PubMed2000

Beta-lactamase producing bacteria in the subgingival microflora of adult patients with periodontitis. A comparison between Spain and The Netherlands.

BACKGROUND/AIMS: Countries with a high per capita antibiotic use frequently demonstrate a high level of drug resistance. The aim of this study was to compare the prevalence and levels of beta-lactamase producing bacteria in the subgingival microflora in adult patients with periodontitis in Spain and The Netherlands, and to characterise beta-lactamase producing bacteria in both patient samples. METHOD: Patients with moderate to severe periodontitis were consecutively selected and asked to report on: current systemic disorders and medications, history of use of antibiotics, and smoking habits. Clinical variables included probing pocket depth, clinical attachment level, plaque, bleeding on probing, and suppuration. Pooled subgingival samples of 4 selected sites were anaerobically cultured in blood agar plates with and without amoxicillin, and amoxicillin/clavulanate. Bacterial colonies growing on amoxicillin plates but not on amoxicillin/clavulanate plates were tested for beta-lactamase production. beta-lactamase producing bacteria were isolated and identified. RESULTS: 31 patients were studied in the Spanish group and 30 in the Dutch group. Comparable mean gender and ages were found. Evaluation of previous antibiotic use revealed that, in the previous 12 months, 54.8% of patients in the Spanish group and 10% in the Dutch group reported antibiotic use (p<0.001). The prevalence of beta-lactamase producing bacteria was 87.1% in the Spanish group and 73.3% in the Dutch group. Total counts of beta-lactamase producing bacteria on amoxicillin plates (p<0.01), the mean number of different beta-lactamase producing colonies per patient (p<0.001), and the number of amoxicillin resistant colonies (p<0.001) were significantly higher in the Spanish group. 74 beta-lactamase producing strains in the Spanish group and 33 in the Dutch group were isolated for identification. 23 out of 35 identified strains in the Spanish group, and 32 out of 33 in the Dutch group belonged to Prevotella genus. CONCLUSIONS: A high prevalence of beta-lactamase producing bacteria has been evaluated in two distinct populations, belonging to two European countries with clear differences in antibiotic usage policy. A higher prevalence and a more complex beta-lactamase producing microflora, were found in the Spanish group, associated with a higher antibiotic consumption. This study shows that a higher use of beta-lactam antibiotics is reflected in the % of beta-lactamase producing bacteria in the subgingival microflora of patients with periodontitis. This information may be important in the treatment of severe periodontitis.

Adult↗
PubMed2000

Actinobacillus actinomycetemcomitans-associated peri-implantitis in an edentulous patient. A case report.

BACKGROUND: Peri-implantitis is a risk factor for implant loss. Late bacterial infection of the peri-implant tissues and loss of alveolar bone in edentulous patients is caused by commensal oral anaerobic bacteria. In partially edentulous patients, Porphyromonas gingivalis and occasionally Actinobacillus actinomycetemcomitans are associated with peri-implantitis lesions. AIMS: To investigate the microbiology of a peri-implantitis case in an edentulous patient. METHODS: Anaerobic culture techniques and selective culture techniques for A. actinomycetemcomitans were used to study the peri-implant microflora at sites with and without bone loss. RESULTS: An anaerobic peri-implant microflora with several putative periodontal pathogens was found at sites with bone loss. Furthermore, a metronidazole-resistant A. actinomycetemcomitans was isolated. The A. actinomycetemcomitans infection did not respond to systemic doxycycline therapy, despite good susceptibility in vitro. CONCLUSIONS: The present case of severe A. actinomycetemcomitans-associated peri-implantitis shows the importance of pre-operative infection control. The findings in this case show that remaining teeth affected by periodontitis can be a serious risk factor for peri-implantitis.

Actinobacillus Infections↗
PubMed2000

Microbiology of destructive periodontal disease in adolescent patients with congenital neutropenia. A report of 3 cases.

BACKGROUND, AIMS: Congenital neutropenia is one condition that may predispose for destructive periodontal disease at a young age. In this report, we describe the microbiology of 3 adolescent patients with congenital neutropenia two of whom suffered from severe periodontitis. METHOD: Microbiological testing of the parents was also performed in 1 case. DNA fingerprinting was used to study transmission of putative periodontal pathogens in this case. From 1 patient with periodontitis, Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis were isolated; a 2nd periodontitis patient was infected with P. gingivalis. A 3rd patient had gingivitis only and no A. actinomycetemcomitans or P. gingivalis were found. RESULTS: Using the amplified fragment length polymorphism DNA fingerprinting technique, bacterial transmission between the father and a patient was shown for A. actinomycetemcomitans but not for P. gingivalis.

Actinobacillus Infections↗
PubMed2000

Differences in the composition of the subgingival microbiota of two periodontitis populations of different geographical origin. A comparison between Spain and The Netherlands.

The purpose of this study was to compare the subgingival microbiota of two geographically distinct patient populations using identical clinical and bacteriological methods. Adult patients with a diagnosis of periodontitis were consecutively selected according to pre-defined clinical criteria. Microbiological samples were taken from the deepest four sites with bleeding. The samples were plated on blood agar plates, for the determination of the total anaerobic counts and identification of specific bacterial pathogens, and on TSBV and McConkey for isolation of Actinobacillus actinomycetemcomitans and enteric rods, respectively. Thirty-one patients in Spain and 30 patients in The Netherlands were selected. Both patient groups showed similar clinical characteristics, both in terms of age, gender and periodontal clinical variables. A. actinomycetemcomitans was significantly more prevalent (23.3% vs. 3.2%) in the Dutch group, while Porphyromonas gingivalis was significantly more prevalent (64.5% vs. 36.7%) in the Spanish group. Bacteroides forsythus and most commensal periodontal pathogens showed similar prevalences, except Peptostreptococcus micros that was significantly more frequent in the Dutch group (96.7% vs. 74.2%). In summary, the subgingival microbiota from the Spanish group was characterised by a high prevalence of P. gingivalis and low of A. actinomycetemcomitans, while the flora from the Dutch group was characterised by a high prevalence of A. actinomycetemcomitans and P. micros.

Aggregatibacter actinomycetemcomitans↗
PubMed2000

Peptostreptococcus micros smooth and rough genotypes in periodontitis and gingivitis.

BACKGROUND: Two genotypes can be distinguished within the species Peptostreptococcus micros: a smooth (Sm) and a rough (Rg) type. To date no systematic study has been performed on the prevalence and proportion of both types in untreated periodontitis patients and subjects without destructive periodontal disease. Therefore, the present study was performed to investigate: 1) the relative importance of the Sm and the Rg genotype of P micros in periodontitis and gingivitis; 2) the correlation between smoking and the 2 genotypes of P micros; and 3) the systemic antibody response against the 2 genotypes in relation to the periodontal condition and smoking. METHODS: A total of 104 untreated periodontitis patients and 41 individuals with gingivitis underwent clinical examination and microbiological sampling. Pocket samples were cultured anaerobically on blood agar plates to determine the prevalence and proportion of the Sm and Rg types of P micros. Serum antibody titers against both types of P micros were determined in all subjects by enzyme-linked immunosorbent assay (ELISA) using whole bacterial cells as antigen. Additionally, in a representative group of subjects, the antigen specificity of the serum antibodies was assessed by immunoblotting experiments. RESULTS: The prevalence of the Sm genotype was higher in subjects with periodontitis (94%) compared to subjects with gingivitis (59%), whereas the prevalence of the Rg type was not significantly different (38% versus 29%). Similar analyses were performed for subgroups of smokers and non-smokers; within the periodontitis group, the prevalence of the Sm type was not different between smokers and non-smokers (96% and 92%, respectively), whereas the prevalence of the Rg type was higher in smokers (48%) compared to non-smokers (19%). No difference in prevalence of both types was observed between smokers and non-smokers within the gingivitis group. The titers and specificity of P micros-specific immunoglobulins in periodontitis patients were not different from those in gingivitis subjects, nor were they related to smoking status or culture-positivity. CONCLUSIONS: The results of this study suggest that both the Sm and the Rg genotypes of P micros are part of the normal oral microbiota. However, the elevated prevalence of the Sm genotype in periodontitis and the elevated prevalence of the Rg type in periodontitis patients who smoke implies that both types can behave as opportunistic pathogens in destructive periodontal disease.

Adult↗
PubMed2000

The mouthwash: a non-invasive sampling method to study cytokine gene polymorphisms.

BACKGROUND: We describe a simple, non-invasive mouthwash sampling method for rapid DNA isolation to detect cytokine gene polymorphisms. In the present paper, interleukin- 1beta(IL-1B) and interleukin-1 receptor antagonist (IL-1RN) gene polymorphisms were studied. METHODS: Two mouthwash samples and blood samples were collected from 11 healthy individuals. The second mouthwash sample was stored for 7 days at room temperature. Polymerase chain reaction amplification was used to identify a bi-allelic polymorphism at position +3953 in the IL-1B gene and a variable number of tandem repeats (VNTR) polymorphism in the IL-1RN gene. RESULTS: Our results show that the typing of these cytokine gene polymorphisms using DNA isolated from mouthwash samples did not differ from those obtained by a phenol/chloroform isolation method from EDTA anti-coagulated blood. Moreover, reliable results from mouthwash samples were obtained after storage for at least 7 days at room temperature. CONCLUSIONS: Mouthwash can be the method of choice to study gene polymorphisms in periodontitis and other chronic inflammatory diseases.

Alleles↗
PubMed2000

[Metronidazole in the treatment of refractory periodontitis].

In this article the clinical and microbiological effects of systemic metronidazole in the treatment of refractory periodontitis in adult patients is discussed. For this study, 27 adult patients with detectable Bacteroides forsythus and culture negative for Actinobacillus actinomycetemcomitans were selected. After renewed supra- and subgingival debridement, patients were treated with systemic metronidazole (500 mg TID) for 7 days. Mean probing pocket depth, probing attachment level and bleeding index significantly improved after metronidazole therapy. Patients that became culture negative for B. forsythus showed a significant better therapy response in comparison to subjects that had detectable B. forsythus post-therapy. The maximum clinical response was observed in patients that became negative for B. forsythus, Porphyromonas gingivalis and Prevotella intermedia after renewed debridement and metronidazole therapy. It is concluded that systemic metronidazole therapy can be effective in refractory adult periodontitis. Microbiological analyses of the subgingival microflora in these patients can assist in selecting patients that may benefit from systemic metronidazole therapy.

Adult↗
PubMed1999

Salivary lactoferrin and low-Mr mucin MG2 in Actinobacillus actinomycetemcomitans-associated periodontitis.

Concentrations and output of lactoferrin and of low-Mr mucin MG2 were determined in saliva of subjects suffering from Actinobacillus actinomycetemcomitans-associated periodontal disease and healthy subjects. Periodontal patients were clinically examined and a microbiological sample was taken from the deepest bleeding pockets in each quadrant. The number of viable A. actinomycetemcomitans was determined in the sampled sites of each patient. The MG2 output in the diseased subjects (13.6 microg protein/min) was decreased at least by a factor three compared to periodontal healthy subjects (44.3 microg protein/min). On the other hand, output of lactoferrin was not significantly different in healthy (9.5 microg/min) and diseased subjects (7.6 microg/min). Western analyses demonstrated a higher iron-saturation of lactoferrin in diseased subjects in comparison with the healthy subjects. Lactoferrin degrading enzymes, probably derived from microbial sources, could be detected in saliva of the periodontally diseased subjects, but not in saliva of healthy subjects. The combination of iron-saturation and degradation of lactoferrin suggests that anti-microbial properties of lactoferrin are diminished in periodontitis patients. Moreover, the low concentration of mucin MG2 suggests a decline in mucin defence and consequently a higher susceptibility for oral infection. A negative correlation (r= -0.4, p < 0.05) between the number of subgingival A. actinomycetemcomitans and lactoferrin in saliva suggested that low concentrations of lactoferrin favour the growth of the bacterium. These data indicate that a decline in the salivary defence system might increase the risk for oral infection by A. actinomycetemcomitans.

Actinobacillus Infections↗
PubMed1999

Clinical and microbiological effects of initial periodontal therapy in conjunction with amoxicillin and clavulanic acid in patients with adult periodontitis. A randomised double-blind, placebo-controlled study.

The aim of the present study was to investigate the clinical and microbiological effects of initial periodontal therapy in conjunction with systemic amoxicillin plus clavulanic acid in adult periodontitis patients using a double-blind, parallel-group, and placebo-controlled protocol. 21 patients with a clinical diagnosis of generalised adult periodontitis were recruited. Clinical measurements and microbiological assessments were carried out at baseline, 3, and 12 months post-treatment. Approximately 6 weeks after initial periodontal treatment (3-6 h), patients were randomly assigned to receive coded study medication of 500 mg amoxicillin plus 125 mg clavulanic acid (Augmentin) or placebo, every 8 h for 10 days. Patients returned for follow-up visits 3, 6, 9, and 12 months after completion of the medication. The mean plaque index (PI) at baseline was 1.1 for placebo group and 0.9 for the test group. At 3 months, the PI had dropped to 0.3 in both groups, and was maintained during the rest of the study. The changes in bleeding on probing (BOP) and gingival index (GI) in the course of the study were similar in both groups. The mean whole mouth probing pocket depth (PPD) in the placebo group was 3.8 mm at baseline and 3.9 mm in the test group. A mean reduction of 1.0 mm in the placebo group and 0.9 mm in the test group was observed during the first 3 months. No further reduction in PPD was noticed during the study period in either group. There was no statistically significant difference in the PPD reduction between the 2 groups. The change in clinical attachment level (CAL) from baseline to 3 months amounted to 0.5 mm in both groups. Between 3 and 12 months, the CAL changed in neither group. In both groups, treatment resulted in a decrease in the number of spirochetes and motile rods in positive patients, but no significant differences between either group were noted in any of the dark field microscopy observations. At baseline, 1 patient in the placebo group and 2 patients in the test group were culture positive for Actinobacillus actinomycetemcomitans (Aa). After therapy, Aa was not detectable in the placebo group and 1 patient remained positive in the test group. In the placebo group, the number of patients positive for Porphyromonas gingivalis (Pg) decreased from 7 to 2 after therapy. In the test group, the 4 patients positive for Pg at baseline remained positive after therapy. In both groups, all subjects were positive for Prevotella intermedia (Pi) and Fusobacterium nucleatum (Fn) at baseline. At 12 months, all subjects had detectable subgingival Fn. 9 out of the 11 placebo and 8 of the 10 test patients remained positive for Pi. There were no differences in detection frequency of Peptostreptococcus micros (Pm) and Bacteroides forsythus (Bf) in both groups between baseline, 3, and 12 months post-treatment. The findings demonstrated that, in comparison to placebo, systemic amoxicillin plus clavulanic acid provided no additional clinical and microbiological effects in the treatment of adult periodontitis patients.

Adult↗
PubMed1999

[Antibiotic resistance in the subgingival microflora in patients with adult periodontitis. A comparative survey between Spain and the Netherlands].

The widespread use of antibiotics for treatment of bacterial infections has lead to the emergence of resistant human pathogens. Great differences have been documented between European countries in the use of systemic antibiotics. In parallel, significant differences in levels of resistant pathogens have been documented. In order to investigate whether differences in antibiotic use influence the level of antimicrobial resistance of the subgingival microflora, microorganisms from the subgingival plaque of untreated patients with adult periodontitis in The Netherlands (n = 30) and Spain (n = 31) were compared. Blood agar plates containing breakpoint concentrations of penicillin, amoxicillin, amoxicillin and clavulanate, metronidazole, erythromycin, azithromycin, clindamycin and tetracycline were used to determine the proportion of bacteria from the subgingival plaque that was resistant to these antibiotics. In the Spanish patients, statistically significant higher mean levels of resistance were found for penicillin, amoxicillin, metronidazole, clindamycin and tetracycline. The mean number of different bacterial species growing on the selective plates was higher in the Spanish patients, as was the percentage of resistant strains of most periodontal pathogens. A striking difference was observed in the frequency of occurrence of tetracycline-resistant periodontal pathogens. In Spain, 5 patients had > 3 tetracycline resistant periodontal pathogens, whereas this was not observed in any of the Dutch patients. It is concluded that the widespread use of antibiotics in Spain is reflected in the level of resistance of the subgingival microflora of adult patients with periodontitis.

Adult↗
PubMed1998

Virulence of six capsular serotypes of Porphyromonas gingivalis in a mouse model.

Capsular structures of Porphyromonas gingivalis have been correlated to the pathogenicity in animal models. Six polysaccharide capsular serotypes have recently been described in P. gingivalis. In the present study, virulence of the P. gingivalis strains of the six capsular serotypes was compared with strains of the non-capsular serotype of P. gingivalis in a mouse model. All 18 encapsulated strains caused a spreading type of infection with exudate, often accompanied by ulceration and necrosis of the skin and a significant loss of body weight. All three non-encapsulated strains tested induced localized abscesses, although a spreading type of infection was occasionally observed. Illness of the mice was almost always associated with recovery of encapsulated P. gingivalis from blood, kidneys, lungs and spleens. A statistically significant contrast was found in the average weight change during the experiment between the mice infected with the K- serotype strains and the mice infected with the encapsulated P. gingivalis strains. Differences in severity of illness and the recovery of P. gingivalis from mouse tissues were recorded between strains of the same serotype. The differences in virulence within a capsular serotype suggest that the capsule is an important but not the only determining virulence factor for P. gingivalis.

Abscess↗
PubMed1998

Prevalence of Peptostreptococcus micros morphotypes in patients with adult periodontitis.

The prevalence of the smooth and rough colonial morphotypes of Peptostreptococcus micros was examined with culture technique in 123 patients with adult periodontitis (age 24-68 years). Of all subgingival samples, 91% contained the smooth morphotype of P. micros. The smooth morphotype constituted a mean percentage of the total anaerobic viable biota of 6.0%, with a range of 0.02-35.7%. Of these samples, 49% contained colonies of the rough morphotype as well, with a mean percentage of the total anaerobic viable biota of 2.3% (range 0.01-16.2%). None of the samples contained only the rough morphotype. The total percentage of P. micros varied from 0.02-35.71% with a mean of 7.2%. No correlation was found between the prevalence of both morphotypes of P. micros and the age of the subjects or with loss of attachment or pocket depth.

Adult↗