The aim of the study was to investigate the infl uence of additive etching of dentine with phosphoric acid on the shear bond strength of two different, self-conditioning.

The aim of the present study was to discover what influence structured reporting (study group = A) of toothcoloured lab-fabricated restorations has on clinical decision-making following international guidelines. By way of comparison, the conventional approach in the form of short reporting with 5 items (control group = B) was used as gold standard. The study was carried out in the first clinical semester of dentistry (n = 68) at the Goethe University in Frankfurt am Main. In the study group, indirect ceramic restorations were assessed on a scale of 1 (very good) to 5 (insufficient) using structured reporting (7 items, each with 5 subgroups) in accordance to World Dental Federation (FDI) - standards. Following this, the clinical decision on the insertion of the restoration was made. To evaluate the quality of the structured reporting, sensitivity, specificity, confidence intervals (Cl) and the respective predictive values (positive = PPV, negative= NPV) were determined. Based on FDI reporting, a ceramic inlay is also favored with a great degree of certainty in clinical decisions: this was the true in 34 procedures out of a total of 38 clinically incorporated ceramic inlays [sensitivity 67% (95% CI: 46%83%); specificity 89% (95% Cl: 75%-97%); PPV 82%, NPV 79%]. In the control group, sensitivity was 56% (95% CI: 35%-75%); specificity 92% (95% CI: 79%-98%); PPV 83%, NPV 74%. No significant differences could be determined between A and B (p = 0.813).

Periodontal disease are chronic infectious disease in which bacteria initiate the host immune response determining at the end of a more or less time damage for tooth. In periodontitis, the clinical findings of bone resorption and loss of clinical attachment level around tooth are a result of inflammatory mediated alterations to the bone remodeling balance. The inflammatory infiltrate present between the plaque biofilm, bone and connective tissues regulate the host immune response to the bacteria.

The aim of this in vitro pilot study was to describe the shaping ability of a rotary nickel-titanium (NiTi) instrument in combination with different torque-controlled endodontic devices and to compare them with NiTi files in combination with a conventional preparation by hand in severely curved root canals of plastic blocks. Thirty blocks simulating a severely curved root canal were divided into three groups (n=10 for each). All canals were prepared with NiTi files to an ISO size of 40 using an apical-coronal preparation technique. Mity Roto 360° files (Loser, Leverkusen, Germany) were used for the automatic systems, while Mity K-Files (Loser, Leverkusen, Germany) were used for the preparation by hand. We evaluated the frequency of instrument failure, the preparation time, loss of working length, loss of weight, elbow-zip effects, and changes in root canal anatomy. The data were analyzed statistically using one-way ANOVA followed by a post hoc Bonferroni test (p < 0.05). A total of three instrument failures were observed: one for Mtwo direct and two for Endo IT. Preparation time was significantly longer when preparing by hand (16.64 min) than for both automatic systems, which did not differ significantly. Critical loss of working length could be detected for all systems (1.3–2.81 mm). Irrespective of the torque-controlled motor, the shape of the canal anatomy was retained better with Mity Roto files than hand preparation. In summary, the two automatic systems did not differ significantly. Within the limitations of this study and especially due to the long working length losses, neither the MTwo direct handpiece nor the Endo IT professional motor can be recommended in combination with Mity Roto 360° files when an apical-coronal preparation method is used in severely curved root canals.

The aim of this randomized in vitro study is to clarify whether resin based restorative materials (RBRM) behave in a way comparable to non-resin based restorative materials (non-RBRM) in dentine-limited cavities with regard to their marginal fit. For this purpose, cylindrical standardized cavities (diameter: 3.0 +/- 0.1 mm, depth: 1.5 mm) were placed on buccal surfaces of sixty human molars and restored with three non-RBRM (glass ionomer cement, amalgam, phosphate cement) and three adhesive (composite, compomer, ormocer) restoratives. Aging of the samples was achieved by thermal cycling (500 cycles). The marginal gaps could be made visible with a dye penetration test (methylene blue 2%). Using a diamond internal hole saw, 5 cuts were made through the cavity and measured under an incident light microscope at 10x magnification. The result of the statistical evaluation of the additionally determined percentage marginal gap depths was compared with the numerical evaluation of the penetration depths of 0, 1 and 2 required by the ISO test setup. The ISO classification reveals statistical differences in the penetration behaviour of phosphate cement to the other materials, whereas the statistical evaluation of the percentage measurement distances revealed significant differences between the nonadhesive and the adhesive restorative materials, with significantly smaller marginal gaps for the cavities of the RBRM group.