Objectives: Evaluation of in vitro efficacy of three different implant surface decontamination methods in a peri-implant bone defect model. Material and methods:A total of 180 implants were stained with indelible red color and distributed to standardized peri-implant bone defect resin models with a circumferential defect angulation of 30°, 60°, or 90° (supraosseous defect). Sixty implants were assigned to each type of defect. All implants were cleaned by the same examiner. For each type of defect, 20 implants were cleaned for 2 min with one of 3 devices: curette (CUR), sonicscaler (SOSC), or air abrasion with glycine powder (APA).Thereafter, photographs were taken from both sides of each implant and the cumulative uncleaned implant surface area was measured by color recognition technique.Scanning electron micrographs (SEM) were examined to assess morphologic surface damages.

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Young patients may benefit from an early removal of mandibular M3, especially in the presence of certain cofactors.

Background: Estimating prognosis of periodontally affected teeth at the beginning of supportive periodontal care (SPC) is an important component for further treatment planning. This study aimed to evaluate tooth loss (TL) during 10 years of SPC in periodontally compromised patients and to identify tooth-related factors affecting TL. Methods: Patients were re-examined 120 ± 12 months after accomplishment of active periodontal therapy. TL was defined as primary outcome variable and tooth-related factors (abutment status, furcation involvement [FI], tooth mobility, mean periodontal probing depth [PD], and clinical attachment level [CAL] at beginning of SPC, and initial bone loss [BL]) were estimated based on an adjusted regression analyses model.Results: Ninety-seven patients (51 females and 46 males; mean age, 65.3 ± 11 years) lost 119 of 2,323 teeth (overall TL [OTL]: 0.12 teeth/patient/y) during 10 years of SPC. Forty of these teeth (33.6%) were lost for periodontal reasons (TLP; 0.04 teeth/patient/y). Significantly more teeth were lost due to other reasons (P <0.0001). TLP (OTL) only occurred in 5.9% (14.7%) of all teeth, when BL was at least 80%. Use as abutment tooth, FI degree III, tooth mobility degrees I and II, mean PD, and CAL positively correlated with OTL (P <0.05). For TLP, FI and tooth mobility degree III as well as mean CAL were identified as tooth-related prognostic factors (P <0.05). Conclusions:During 10 years of SPC, most of the teeth (93.4%) of periodontally compromised patients were retained, showing the positive effect of a wellestablished treatment concept. Well-known tooth-related prognostic factors were confirmed.

Aim Evaluation of 20‐year results after open flap debridement (OFD) and guided tissue regeneration (GTR) of infrabony defects in a randomized controlled trial. Materials and methods In originally 16 periodontitis patients (baseline examination), periodontal surgery was performed in 44 infrabony defects. Polylactide acetyltributyl citrate barriers were randomly assigned to 23 out of these 44 defects (parallel). Ten of these patients (GTR) exhibited a second, contra‐lateral defect (OFD) each (split‐mouth). At baseline, 12, 120 and 240 ± 12 months after surgery probing depths, attachment level, bleeding on probing as well was Plaque Index, Gingival Bleeding Index and plaque control record were obtained. Results Twelve patients contributing 38 defects were available at 240 months. At 12, 120 and 240 ± 12 months, both groups showed significant (p < 0.01) attachment gain (split‐mouth: OFD: 12 months: 4.15 ± 2.93 mm; 120 months: 3.35 ± 2.37 mm, 240 months: 3.60 ± 2.55 mm; GTR: 12 months: 3.50 ± 2.47 mm; 120 months: 3.90 ± 2.76 mm, 240 months: 3.80 ± 2.69 mm; parallel: OFD: 12 months: 3.53 ± 2.04 mm; 120 months: 3.59 ± 2.54 mm, 240 months: 3.53 ± 2.50 mm; GTR: 12 months: 4.07 ± 2.88 mm; 120 months: 3.13 ± 2.22 mm, 240 months: 3.13 ± 2.22 mm). Seven teeth (3 OFD, 4 GTR) were lost. Only 1 patient out of 12 was kept in regular supportive periodontal therapy (SPT) over 20 years. The study failed to show significant attachment gain differences between both groups after 240 months. Conclusions Twenty years after OFD and GTR in infrabony defects in a population with lack of regular SPT attachment gains at 12 months after surgery were stable. About 82% of the initially included teeth were still in place.