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Objective: To present the application of two different soft tissue grafts around dental implants during stage-two surgery. Furthermore, the ultrastructure of these materials is shown and discussed using scanning electron microscopy (SEM). Summary: Although soft tissue autografts may be currently regarded as the gold standard, harvesting of these grafts might lead to higher morbidity, longer chair time, and intra-/postoperative complications at the donor site. New developments in collagen scaffolds have provided an alternative to successfully replace autologous grafts in clinical practice. The SEM pictures clearly show the different composition of a bilayer scaffold (collagen matrix, CM) and a porcine acellular dermal matrix (ADM). These distinctive properties lead to different possible indications. Within the presented cases, ADM was used to augment the ridge contour and was placed into a buccal pouch to achieve complete coverage and an uneventful closed healing. On the other side, CM was left exposed to the oral cavity to successfully gain keratinized mucosa around and between two dental implants. [ABSTRACT FROM AUTHOR]

Objective: To study the clinical applicability of porcine dermal matrix for treatment of recession type defects. Method and Materials: Twenty-eight gingival recessions in six patients were selected for root coverage procedures using a modified tunneling technique and porcine dermal matrix. As primary outcome, depth and width of gingival recession were assessed at baseline and at 6 and 12 months postoperatively. As a secondary outcome, the width of keratinized tissue was studied. Results: At 6 and 12 months postoperatively, mean root coverage was 65.52% and 56.82%, respectively. Complete root coverage was achieved in 42.86% of the treated defects.Conclusion: Porcine dermal matrix may potentially be used as a replacement material for autologous tissue. However, complete root coverage was only achieved in less than half of the studied defects. [ABSTRACT FROM AUTHOR]

In the design of parts consisting of long-fibre-reinforced Sheet Moulding Compounds (SMC), the potential for the optimisation of processing parameters and geometrical design is limited due to the high number of interdependent variables. One of the influences on fibre orientations and therefore mechanical part performance is the initial filling state of the compression moulding tool, which is defined by the geometry and positioning of the SMC preform. In the past, response surface methodology and linear regression analysis were successfully used for a simulation-based optimisation of rectangular preform size and position in regard to a part performance parameter. However, the computational demand of these increase exponentially with an increase in the number of design variables, such as in the case of more complex preform geometries. In this paper, these restrictions are addressed with a novel approach for metamodelling the correlation of preform and the resulting mechanical part performance. The approach is applied to predicting the maximum absolute deflection of a plate geometry under bending load. For metamodelling, multiple neural networks (NN) are trained on a dataset obtained by process and structural simulation. Based on the discretisation of the plate geometry used in these simulation procedures, the binary initial filling states (completely filled/empty) of each element are used as inputs of the NNs. Outputs of the NNs are combined by ensemble modelling to form the metamodel. The metamodel allows an accurate prediction of maximum deflection; subsequent validation of the metamodel shows differences in predicted and simulated maximum deflection ranging from 0.26% to 2.67%. Subsequently, the metamodel is evaluated using a mutation algorithm for finding a preform that reduces the maximum deflection. [ABSTRACT FROM AUTHOR]

The necessity of surgical root coverage is often encountered in daily clinical practice, mainly because of esthetic reasons. Despite the variety of available surgical techniques, delicate clinical scenarios may require refined surgical therapy approaches. The presented double sliding flap technique is designed to meet the special requirements encountered in the often-fragile incisal mandibular area. This surgical approach combines two laterally repositioned flaps with the dissection of the frenulum, to cover two deep neighboring recessions in the area of the central incisors. Providing that correct indication and adequate surgical tissue handling are used, this complex and advanced technique may have the potential to achieve complete longterm root coverage and an esthetically satisfying treatment outcome. [ABSTRACT FROM AUTHOR]

[Display omitted] To increase the mechanical properties of sheet moulding compound (SMC) and extend the application on structural components, cost-effective towpreg-based grid-like structures with varying spacing, layers and layout were constructed, numerically studied on the tray-based 3D part and finally defined, which were co-moulded with SMC in the one-shot compression process. The hybridisation effect on the global and local elastic flexural property was experimentally characterised for the 3D part and 2D plate. For the 2D plate, an adapted analytical model was proposed treating the hybrid SMC as a laminate of different plies. A parametric study evaluated the influence of manufacturing process variables on predictive accuracy. Plateau-shaped out-of-plane waviness in towpreg was identified as the critical variable, and one adapted exponential power distribution was tailored to capture the waviness and integrated into the analytical model. Furthermore, demand for thinner towpreg was identified. [ABSTRACT FROM AUTHOR]