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Notes: Abstract The purpose of this proof of principle trial was to assess whether conventional periodontal therapy and systemically administrated acetylsalicylic acid (ASA) are functionally synergistic when combined in the treatment of periodontitis, A total of 30 patients with untreated moderate to severe adult periodontitis were enrolled into the study and were given placebo q.i.d. between the baseline and 6-week examination, and acetylsalicylic acid (ASA) 500 mg q.i.d. between the 6-week and 12-week examinations. In addition, they received supra-and subgingival scaling in 1 quadrant after baseline examination and in 2 further randomly selected quadrants after the 6-week examination. The study design resulted in the following 4 therapies: (1) scaling plus ASA 500 mg q.i.d.: (2) scaling plus placebo q.i.d: (3)ASA 500 mg q.i.d. alone: (4) placebo q.i.d. alone. Two-way analysis of variance showed functional synergism of ASA and scaling, resulting in a therapeutic efficacy approximately equivalent to the sum of each individual therapeutic efficacy (i.e., ASA alone and scaling alone) in reducing gingival inflammation and pocket probing depth over the 6-week observation period (interaction: p 〉0.05). Only the effect of ASA was significant m reducing the concentration of elastase-α1-proteinase inhibitor in gingival crevicular fluid (GCF E-α1-PI) (p 〉0.001), reduction in GCF E-α1-PI concentrations by ASA may indicate a decreased risk in periodontal disease progression. The results suggest that the combination of therapies and their different mechanisms of action, i.e., reduction of bacterial plaque and inhibition of destructive components of the immune responses, may result in functionally synergistic therapeutic efficacies in patients with untreated adult periodontitis.

Notes: Abstract 35 patients receiving regular supportive periodontal therapy (SPT) and showing signs of localized persistent or recurrent periodontitis were enrolled in the study. Within 1 week after SPT, each patient had a tetracycline HCl loaded ethylene vinyl acetate co-polymer fiber placed into the periodontal pocket of 1 randomly selected tooth with persistent or recurrent periodontitis (test); the fiber was removed after 9.5±2.0 days. A non-adjacent tooth with persistent or recurrent periodontitis in a separate quadrant, which received no further treatment, served as a control. A total of 28 patients completed the 6-month study. Compared to control teeth, in test teeth at 6 months significantly (p 〈 0.01) lower scores were found for gingival index, pocket probing depths, and PMN elastase-α1-proteinase inhibitor concentrations in gingival crevicular fluid. With the exception of plaque index scores, test teeth demonstrated significant reductions from baseline to 6 months in all parameters (p 〈 0.05). Conversely, all parameter measurements in control teeth, except bleeding on probing, showed no significant difference between baseline and 6-month values. The results suggest that the use of controlled topical application of tetracycline HCl may improve periodontal health and reduce the risk of disease progression in localized persistent or recurrent periodontitis. Moreover, the effects of this application appear to be sustained for at least 6 months.

Notes: Abstract. 48 adult patients with untreated periodontitis harboring subgingival Actinobacillus actinomycetemcomitans and/or Porphyromonas gingivalis were randomly assigned to receive full mouth scaling alone (control) or scaling with systemic metronidazole plus amoxicillin and supragingival irrigation with chlorhexidine digluconate (test). Subgingival plaque and swab samples from tongue, tonsils, and buccal mucosa were taken at baseline, 10 days and 3, 6, 9, and 12 months. A. actinomycetemcomitans was detected in the oral cavity, i.e., subgingival plaque and/or mucous membranes. Less frequently in test patients compared to controls at 9 and 12 months (p〈0.01. whereas, the intraoral detection frequency of P. gingivalis was significantly reduced only 10 days following therapy (p〈0.001). At any time after therapy. A. actinomycetemcomitans was not detected intraorally in 5 of 10 (50%) test and 1 of 13 (8%) control patients harboring this pathogen at baseline; P. gingivalis was not detected in only 1 of 18 (6%) test and none of the 17 control patients harboring this pathogen at baseline. Although the data indicated that the assessed antimicrobial therapy may suppress A. actinomycetemcomitans from the entire oral cavity below detectable levels over a minimum of 12 months. P. gingivalis persisted or reoccurred.

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: Abstract. 48 adult patients with untreated periodontitis harboring subgingival Actinobacillus actinomycetemcomitans and/or Porphyromonas gingivalis as assessed by PCR were randomly assigned to receive full-mouth sealing alone (control) or scaling with systemic metronidazole plus amoxicillin and supragingival irrigation with chlorhexidine digluconate (test). In patients harboring A. actinomycetemcomitans intraorally at baseline, the adjunctive antimicrobial therapy resulted in a significantly higher incidence of probing attachment level (PAL) gain of 2 mm or more compared to scaling alone over 12 months (P〈 0.05). In addition, suppression of A. actinomycetemcomitans in subgingival plaque below delectable levels was associated with an increased incidence of PAL gain. In contrast, patients initially harboring P. gingivalis but not A. actinomycetemcomitans in the oral cavity showed a significantly higher incidence of PAL loss following adjunctive antimicrobial therapy compared to scaling alone (P〈0.05). When the presence of pathogens at baseline was disregarded in the analysis, adjunctive antimicrobial therapy did not significantly enhance clinical treatment outcome. The results indicated that adults with untreated periodontitis harboring A. actinomycetemcomitans may benefit from the adjunctive antimicrobial therapy for a minimum of 12 months, whereas, the regimen may adversely affect the clinical treatment outcome of patients harboring P. gingivalis but not A. actinomycetemcomitans.

Notes: Abstract. This study assessed defect depth and volume resulting from root instrumentation using a piezoelectric ultrasonic sealer with a slim scaling tip in vitro. Combinations of the following working parameters were analyzed: lateral forces of 0.5 N, 1 N, and 2 N; tip angulations of O°. 45°. and 90°; power settings of low. medium and high: and instrumentation time of 10 s. 20 s. 40 s. and 80 s. Defects were quantified using a 3D optical laser scanner. Overall, lateral force had the greatest influence on defect volume compared to instrument power setting and tip angulation (β-weights 0.49±0.04, 0.25±0.D4, and 0.14±0.04, respectively). The effects on defect depth were highest for tip angulation followed by lateral force and instrument power setting (β-weights 0.48±0.04. 0.34±0.04, and 0.25±0.04, respectively). Interestingly, al all power settings, the highest defect volume and depth by far were found after combining 45° tip angulation with 2 N of lateral force. The efficacy of the assessed piezoelectric ultrasonic sealer may be adapted to the various clinical needs by adjusting the lateral force. tip angulation, and power setting. To prevent severe root damage it is crucial to use the assessed sealer at a tip angulation of close to 0°.

Notes: This study investigated the efficiency of chemical activation of dual-cure resin-based luting cements as compared with light- and dual-curing. Curing was performed by (i) mixing base and catalyst without subsequent irradiation (chemical curing=CC), (ii) mixing base and catalyst with direct irradiation (dual-cure=DC) or with (iii) irradiation through 2·5 mm of leucite-reinforced glass–ceramics (IPS Empress, Ivoclar) (dual-cure through porcelain=DCtP), (iv) using only the base paste with direct irradiation (light-curing=LC) or with (v) irradiation through porcelain (light-curing through porcelain=LCtP). Specimens of four fine-hybrid DC resin composites and one self-cure hybrid resin composite (only CC) were prepared and tested after 24 h for flexural strength, modulus of elasticity (ISO 4049) and surface hardness (Vickers). For all materials and parameters, dual-curing produced higher values than LC, even when irradiation was performed through porcelain. Following self-curing without photo-activation, flexural strength was 68˙9–85˙9%, the modulus 59˙2–94˙5% and Vickers hardness 86˙1–101˙4% of the corresponding values obtained by dual-curing with direct irradiation. Light-curing through porcelain as compared with direct irradiation reduced the values for most parameters and materials. In contrast, dual-curing maintained flexural strength for all, the modulus for three and the hardness for one of the materials. The mechanical properties of the self-curing resin cement ranged between those of the DC materials.

Notes: Abstract This study assessed defect depth and volume resulting from root instrumentation using a KaVo Sonicflex Lux 2000 L sonic scaler with a slim scaling tip (Perio-Tip no. 8) in vitro. Combinations of the following working parameters were analyzed: lateral forces of 0.5 N, 1 N, and 2 N; tip angulations of 0°, 45°, and 90°; and instrumentation time of 10 s, 20 s, 40 s, and 80 s. Defects were quantified using a three-dimensional optical laser scanner. Instrumentation time had an almost linear impact on defect depth and volume. Although lateral force (β-weight 0.55±0.062) had a greater influence on defect volume than tip angulation (β-weight 0.29±0.062), their effects on defect depth were similar (β-weight 0.43±0.052 and 0.50±0.052, respectively). The combination of force and angulation showed synergistic effects resulting in a wide range of defect depths (21.9±0.96 µm to 174±28.8 µm, at 40 s) and volumes (0.056±0.019 mm3 to 0.68±0.10 mm3 at 40 s). Severe root damage (〉50 µm/40 s) did not occur at any combination of 0.5 N lateral force and/or 0° tip angulation. By adjusting lateral force and tip angulation, the efficacy of the assessed sonic scaler may be adapted to various clinical needs.

Notes: Abstract The purpose of the present study was to decide whether composite resin or conventional glass ionomer cement should be preferred as a base material in endodontically treated premolars. Twelve extracted human maxillary premolars were mounted in a universal testing machine at a 35° angle. Cuspal stiffness was determined by applying a load of 75 N to the buccal cusp and recording the displacement of the cusp using inductive displacement transducers. In the same teeth, different cavity preparations and restorations were performed sequentially. Standard MOD cavities were enlarged to allow endodontic access. In addition, the cusps were undermined. Half of the teeth were restored to the level of the previous shallow cavities using conventional glass ionomer cement (Ketac Fil), in the rest of the teeth dentine bonding agent (Syntac) and composite resin (Tetric) were used instead. Finally, composite resin fillings (Tetric) were placed. All restorations were removed and the experiments were repeated twice. For each replication, the assignment of the base materials to the experimental groups was reversed, and ceramic inlays (Empress) were used as final restorations for the last replication. Improvement of cuspal stiffness achieved by conventional glass ionomer bases was very small, whereas composite resin bases increased cuspal stability by more than a factor of two. After placement of the final restorations, however, there was no longer a difference between teeth with different base materials. Nevertheless, composite resin bases might be preferred for two reasons. Firstly, deterioration of adhesive restorations will probably start at the cavosurface margins. The incidence of margin gaps, however, will not only compromise marginal seal but also the stabilizing effect of the restoration. In this situation, the resin base may still stabilize the tooth. Moreover, resin bases may reduce the risk of cusp fracture during the time between cavity preparation and the insertion of adhesive inlays.

Notes: Abstract  The plasma arc curing light Apollo 95 E (DMDS) is compared to conventional curing lights of different radiation intensities (Vivalux, Vivadent, 250 mW/cm2; Spectrum, DeTrey, 550 mW/cm2; Translux CL, Kulzer, 950 mW/cm2). For this purpose, photoactivated resin composites were irradiated using the respective curing lights and tested for flexural strength, modulus of elasticity (ISO 4049), and hardness (Vickers, Knoop) 24 h after curing. For the hybrid composites containing only camphoroquinone (CQ) as a photoinitiator (Herculite XRV, Kerr; Z100, 3 M), flexural strength, modulus of elasticity, and surface hardness after plasma curing with two cycles of 3 s or with the step-curing mode were not significantly lower than after 40 s of irradiation using the high energy (Translux CL) or medium energy conventional light (Spectrum). However, irradiation by only one cycle of 3 s failed to produce adequate mechanical properties. Similar results were observed for the surface hardness of the CQ containing microfilled composite (Silux Plus, 3 M), whereas flexural strength and modulus of elasticity after plasma curing only reached the level of the weak conventional light (Vivalux). For the hybrid composites containing both CQ and photoinitiators absorbing at shorter wavelengths (370–450 nm) (Solitaire, Kulzer; Definite, Degussa), plasma curing produced inferior properties mechanical than conventional curing; only the flexural strength of Solitaire and the Vickers hardness of Definite reached levels not significantly lower than those observed for the weak conventional light (Vivalux). The suitability of plasma arc curing for different resin composites depends on which photoinitiators they contain.