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Notes: Objectives:  The purpose of this study was to determine the relative impact of various predictors responsible for the variability in treatment outcome after guided tissue regeneration (GTR) in intraosseous periodontal defects.Patients and methods:  30 patients with chronic periodontitis and at least one intraosseous periodontal lesion (≥4 mm) were enrolled. Following full-mouth scaling, GTR using polylactic acid membranes was performed at one site in each patient. Main periodontal pathogens, defect morphology, membrane exposure and smoking habit were assessed as predictor variables. Alveolar bone level change served as the primary outcome variable in a multiple regression analysis.Results:  After 12 months, the 29 patients completing the study showed alveolar bone changes ranging from 4 mm bone gain to 1 mm bone loss (mean: 1.6±0.4 mm gain). Active smoking (β-weight:-0.49, P=0.003) and persistence of subgingival infection with P. gingivalis (P.g.) (β-weight:-0.25, P=0.11) were associated with poor treatment outcome. Deep initial intraosseous defects (β-weight: 0.32, P=0.045) were associated with favorable treatment outcome, and membrane exposure had no impact on bone gain.Conclusion:  Active smoking was the strongest predictor variable negatively affecting alveolar bone gain following GTR in the treatment of periodontal defects. It was followed by a positive influence of a deeper intraosseous defect and by a negative effect by persistent subgingival infection of P. gingivalis. The relative impact of these factors may be useful in assessing the prosgnosis of GTR in intraosseous periodontal defects.

Notes: Abstract. The purpose of this study was to assess the prognostic value of the IL-1 haplotype on the progression of periodontal disease following therapy. 48 adult patients with untreated periodontitis harboring Actinobacillus actinomycetem-comitans and/or Porphyromonas gingivalis were randomly assigned to receive full-mouth scaling alone (control) or in combination with systemic metronidazole plus amoxicillin and supragingival irrigation with chlorhexidine digluconate (test). All patients received supportive periodontal therapy at 3 to 6 months intervals. In 33 patients, lymphocyte DNA was analyzed for polymorphism in the IL-1A gene at position –889 and IL-1B gene at position +3953. Overall, 16 of 33 patients (7 of 17 test and 9 of 16 control) carried the IL-1 haplotype. 2 years following initial periodontal therapy, no differences in the survival rates of sites or teeth not exhibiting probing attachment loss of 2 mm or more compared to baseline, were found between patients who tested positive (85% sites, 53% teeth) and patients who tested negative (89% sites, 56% teeth) for the IL-1 haplotype. The results indicated that the IL-1 haplotype may be of limited value for the prognosis of periodontal disease progression following non-surgical periodontal therapy.〈section xml:id="abs1-1"〉〈title type="main"〉ZusammenfassungInterleukin-1-Haplothyp und Progression der Parodontalerkrankung nach der TherapieDer Zweck dieser Studie war es, den prognostischen Wert des IL-1-HapIotyps bezüglich der Progression einer Parodontalerkrankung nach der Behandlung zu bestimmen. Achtundvierzig erwachsene Patienten mit unbehandelter Parodontitis und Vorhandensein von Actinobacillus actinomycetemcomitans und/oder Porphyromonas gingivalis wurden randomisiert, entweder mit ausschließlichem Scaling des gesamten Gebisses behandelt (Kontrolle) oder in Kombination mit systemischem Metronidazol plus Amoxicillin und supragingivaler Spülung mit Chlorhexidin-Diglukonat (Test). Alle Patienten erhielten in 3 bis 6-monatigen Intervallen eine parodontale Erhaltungstherapie. Bei 33 Patienten wurde die DNA der Lymphozyten hinsichtlich Polymorphismus der IL-1A-Gene in der Position -889 und IL-1B-Gene in der Position +3953 analysiert. Ingesamt trugen 16 von 33 Patienten (7 von 17 Test und 9 von 16 Kontrolle) den Il-1-Haplotyp. Zwischen den Patienten die IL-1-Haplotyp-positiv getestet wurden (85% Flächen, 53% Zähne) und Patienten, die negativ getestet wurden (89% Flächen, 56% Zähne), wurden zwei Jahre nach initialer Parodontalbehandlung keine Unterschiede in den Überlebensraten von Flächen oder Zähnen, die bezüglich Ausgangssituation keinen klinischen Attachmentverlust von 2 mm oder mehr aufwiesen, vorgefunden. Die Ergebnisse zeigten, daß der IL-1-Haplotyp von eingeschränktem Wert für die Prognose der Progression der Parodontalerkrankung nach der konservativen Therapie sein könnte.〈section xml:id="abs1-2"〉〈title type="main"〉RésuméHaplotype d'interleukine-1 et progression de la maladie parodontale après traitementLe but de cette étude est d'évaluer la valeur pronostique de l'haplotype d'interleukine-1 (IL-1) pour la progression de la maladie parodontale après traitement. 48 patients adultes avec parodontite non traitée, abritant Actinobacillus aclinomycetemcomitans et/ou Porphyromonas gingivalis, ont été répartis au hasard dans des groupes de traitement devant recevoir un détartrage de toute la bouche, soit seul (groupe témoin) soit combiné avec l'administration systémique de métronidazole+amoxicilline et l'irrigation susgingivale avec le digluconate de chlorhexidine (test). Tous les patients ont reçu un traitement de maintenance parodontale à des intervalles de 3 à 6 mois. Ches 33 patients l'ADN de lymphocyte a été analysé en ce qui concerne le polymorphisme dans le gène d'IL-1A en position -889 et dans le gène d'IL-1B en position +3953. Dans l'ensemble, 16 des 33 patients (7 des 17 tests et 9 des 16 témoins) étaient porteurs de l'haplotype d'IL-1. Deux ans après le traitement parodontal initial, aucune différence dans le taux des sites ou dents ayant survécu, ne présentant pas de perte d'attache de 2 mm ou plus par rapport au début, n'a été trouvée entre les patients dont le test pour l'haplotype d'IL-1 était positif (85% des sites, 53% des dents) et les patients dont le test était négatif (89% des sites, 56% des dents). Les résultats indiquaient que l'haplotype dTL-1 peut avoir une valeur limitée pour le pronostic de la progression de la maladie parodontale après un traitement parodontal non chirurgical.

Notes: Objectives: The purpose of this study was to assess the dynamics of bacterial colonization in intra-osseous defects following guided tissue regeneration (GTR) therapy using a resorbable barrier.Patients and methods: In each of 30 patients, one intra-osseous defect was treated with GTR using a polylactic acid membrane (Guidor®). Plaque samples were taken from the defect site, other teeth and mucous membranes following initial therapy (baseline), and at 3, 6 and 12 months after periodontal surgery. Additionally, samples were taken from the defect sites at 1, 2 and 4 weeks. Actinobacillus actinomycetemcomitans (A.a.), Porphyromonas gingivalis (P.g.), and Bacteroides forsythus (B.f.) were detected by polymerase chain reaction (PCR). Supportive periodontal therapy was performed at 3-month intervals.Results: In the 29 patients completing the study, the assessed microflora was detected in 3 (A.a.), 13 (P.g.) and 14 (B.f.) defect sites at baseline, in 2 (A.a.), 2 (P.g.) and 2 (B.f.) following surgical debridement, and in 6 (A.a.), 10 (P.g.) and 22 (B.f.) at 12 months. Defect site colonization following GTR therapy was significantly correlated with presurgical colonization at other assessed teeth (A.a. and P.g.: tau = 0.45 and 0.66, respectively; P 〈 0.001), or on mucous membranes (B.f.: tau = 0.44, P 〈 0.001).Conclusion: The colonization of periodontal pathogens at sites treated by GTR may correlate with the intra-oral presence of these pathogens before surgery. If colonization of GTR sites by periodontal pathogens is to be prevented, intra-oral suppression/eradication of these pathogens may be required before surgery.

Notes: Objective:  The aim of the present study was to determine sequence variations in the active centre of the Arg-X-specific protease encoding genes rgpA and rgpB of clinical Porphyromonas gingivalis isolates and to analyse their prevalence in periodontitis patients before and 3 months after mechanical periodontal therapy.Background:  Genetic diversity at nucleotides 281, 283, 286 and 331 has been shown to result in amino acid substitutions in the catalytic domain of RgpA and RgpB that affect the substrate specificity and thus may influence the efficacy of Arg-X-protease specific inhibitors.Methods:  Sequence analysis of rgpA and rgpB genes in clinical P. gingivalis strains isolated from subgingival plaque samples of 82 periodontitis patients before and 3 months after mechanical supra- and subgingival debridement was performed.Results:  No specific variation within the rgpA sequence was observed. However, the rgpB sequence in the region of the active centre showed five different rgpB genotypes, which were named NYPN, NSSN, NSSK, NYPK and DYPN according to the derived amino acid substitution. Porphyromonas gingivalis genotype NYPN was detected in 27 patients (32.9%) before and in 8 patients (9.8%) after therapy, NSSN in 26 (31.7%) and 10 (12.2%), NSSK in 22 (26.8%) and 2 (2.4%), NYPK in 5 (6.2%) and 1 (1.2%), and DYPN in 1 patient (1.2%) and 0 patients (0%), respectively. Only one patient (1.2%) harboured two P. gingivalis rgpB genotypes (NSSK/NYPN) before treatment; these were no longer detected after therapy.Conclusion:  The results indicate that five rgpB genotypes are maintained in natural populations of P. gingivalis. These data may be of importance with regard to the development of specific rgpB inhibitors.

Notes: Objectives:  In 34 patients with chronic periodontitis, the presence of IgA, IgG, and IgG subclass serum antibodies against recombinant PrtC (rPrtC) of Porphyromonas gingivalis was assessed by immunoblot analysis 24 months after therapy.Methods:  rPrtC was produced from P. gingivalis ATTC 33277 using the plasmid pGEX-2T. In addition, intraoral colonization with P. gingivalis was detected by PCR in subgingival plaque and swab samples from buccal mucosae, tonsils and tongue at baseline, 10 d, and 3, 6, 9, 12, 18, and 24 months.Results:  All patients were found to harbor P. gingivalis in the oral cavity at least once during the observation period. The identified antibody responses against the rPrtC of P. gingivalis were IgA (97%, i.e. 33/34 patients) and IgG (100%, i.e. 34/34), with an IgG subclass distribution of IgG2 (65%, i.e. 22/34 patients) 〉 IgG3 (47%, i.e. 16/34) 〉 IgG1 (38%, i.e. 13/34) 〉 IgG4 (29%, i.e. 10/34). Anti-rPrtC IgA and IgG antibody reactivity was found in all but one patients (anti-rPrtC IgA negative), who tested negative for P. gingivalis at all of the assessed intraoral sites for at least 6 months before sera collection. There was no association between IgG subclass reactivity against the rPrtC of P. gingivalis and progression of periodontal attachment loss.Conclusion:  The results indicated that anti-rPrtC IgA and IgG antibodies may serve as an indicator for past or present intraoral colonization with P. gingivalis.