ObjectiveThe aim of this study was to evaluate the susceptibility of dentin to brushing abrasion using four different toothbrushes (rotating-oscillating, sonic and two types of manual toothbrushes) with the same brushing forces.MethodsDentin samples (n = 72) were selected from 72 impacted third molars. Half of the surface of dentin samples was covered with an adhesive tape, creating a protected and a freely exposed area in the same specimen. Brushing was performed with either a: sonic (Sonicare PowerUp, Philips GmbH, Hamburg, Germany), b: oscillating-rotating (Oral B Vitality Precisions Clean, Procter & Gamble, Schwalbach am Taunus, Germany) or two different manual toothbrushes c: flat trim brush head toothbrush (Dr. Best: Original, Glaxo-Smith-Kline, Bühl, Germany) and d: rippled-shaped brush head toothbrush (Blend-a-Dent, Complete V-Interdental, Blend-a-med, Schwalbach, Germany) in a custom made automatic brushing machine. The brushing force was set to 2 N and a whitening toothpaste (RDA = 150) was used. The simulation period was performed over a calculated period to mimic a brushing behavior of two times a day brushing for eight years and six months. Dentin loss was quantitatively determined by profilometry and statistically analyzed by Wilcoxon and Mann-Whitney-U Test (p < 0.05).ResultsThe mean (standard deviation) surface loss was 21.03 (±1.26) μm for the sonic toothbrush, 15.71 (±0.85) μm for the oscillating-rotating toothbrush, 6.13 (±1.24) μm for the manual toothbrush with flat trim brush head and 2.50 (±0.43) μm for the manual toothbrush with rippled-shaped brush head. Differences between all groups were statistically significant at p<0.05.ConclusionUsing the same brushing force and a highly abrasive toothpaste, manual toothbrushes are significantly less abrasive compared to power toothbrushes for an 8.5—year simulation.

Purpose. Most studies about retinal detachment cover a limited follow-up period. The purpose of this research is to assess the long-term results after pars plana vitrectomy (PPV) and scleral buckle (SB) surgery in patients with rhegmatogenous retinal detachment (RRD). Methods. 155 patients with RRD are treated either with SB or PPV with a mean follow-up of more than 5 years. Retrospective analysis of patient data with RRD was performed between January 2006 and June 2008 at a tertiary eye clinic. Results. Overall primary success rate was 85.2% (PPV: 84.6%, SB: 89.5%; p=0.57). 90.5% of redetachments appeared within the first 124 days. No significant different success rate was found for vitrectomy with and without additional encircling band (p=0.09). No advantage of a supplemental encircling band in cases of preoperative inferior breaks was seen (p=0.81). Patients of SB group were treated more frequently in follow-up time because of epiretinal membrane (ERM) (SB: 15.5% versus PPV: 7.3%). No patient of the PPV group without intraoperative use of endolaser cerclage (14.7%) had any peeling surgery postoperatively. Conclusion. Redetachment rates of both methods are comparable in a clinical setting where PPV is considered a suitable method for pseudophakic patients and in complex cases and SB was performed in younger phakic patients with clearly identified retinal tears. PPV seems to show a more heterogenous pattern of complications. No advantage of a supplemental encircling band could be found in these case series of patients with primary RRD. No relevant long-term risk of redetachment was seen after SB.

No abstract