All paired and two midline
labial landmarks had significant displacements, ranging from 13% (Subnasale landmark) to 103% (left Cheilion landmark) of veneer thickness (2 mm thick). A significant positive correlation was obtained between the lower lip displacement and overjet values. The vestibular shift of maxillary incisors and canines affect both upper and lower vermilion areas, without involving cutaneous perilabial landmarks. “
“This study compares the FEA-calculated stresses generated within the supporting periodontal structure of a mandibular second molar restored with a full ceramic crown and with a porcelain-fused-to-metal (PFM) crown, each Silmitasertib research buy resisting occlusal forces acting at different inclinations. Three-dimensional finite element models representing the crown of an unrestored mandibular second molar and two relevant restoration designs were constructed. Two designs represented the molar restored with a full ceramic crown and with a PFM crown, each cemented with the same resin cement. Occlusion was assumed at three contact areas, which equally shared a 100 N force. The analysis was carried out for forces located in the bucco-axial-lingual plane at five inclinations, 0, 22.5°, 45°, 67.5°, and 90°, measured from the axial direction of the tooth. The magnitudes and sites of the maximum equivalent stress (MES)
generated within the supporting periodontium of each analyzed model were collected. Generally, there were no significant differences in the site and magnitude of MES click here in the regions of the supporting structure for the analyzed models. The MES was located at the tooth periodontal ligament (PDL) bifurcation area and distal root apex, crestal bone at the junction between cortical and cancellous else bone, and the distal wall of the mesial root socket of cancellous
bone. The highest stresses corresponded to a horizontal load, followed by the axial load in the PDL and cortical zones. The results show opposite observations for the cancellous bone. The lowest stresses were generated under a load inclination between 22.5° and 45°. Considering the stresses generated within the supporting structures, the present work validates, by calculation, the proposed clinical use of either a full ceramic crown or a PFM crown as a restoration for mandibular second molars. “
“This study evaluated the adherence of dental porcelain to a milled, noncast titanium (Ti) surface with a gold sputter coating to evaluate a possible new practical surface treatment for enhancing the bond strength between Ti and porcelain. Milled, noncast Ti strips were created by computer-aided design and manufacturing processes. The milled, noncast Ti strips were sandblasted with alumina particles and were then sequentially subjected to gold sputter coating treatments of 150- and 300-second duration. Low-fusion dental porcelain was then sintered onto the surface-treated Ti strips.