A Biomechanical Analysis of the Influence of the Morfology of the Bone Blocks Grafts on the Transfer of Tension or Load to the Soft Tissue by Means of the Finite Elements Method.

Edentulism produces resorption of alveolar bone processes, which can complicate placement of dental implants. Guided bone regeneration techniques aim to recover the volume of bone. These treatments are susceptible to the surgical technique employed, the design of the autologous block or the tension of the suture. These factors can relate to major complications as the lack of primary closure and dehiscence. The present study, using finite element analysis, aimed to determine differences in terms of displacement of the oral mucosa, transferred stress according to Von Mises and deformation of soft tissue when two block graft designs (right-angled and rounded) and two levels of suture tension (0.05 and 0.2 N) were combined. The results showed that all the variables analyzed were greater with 0.2 N. Regarding the design of the block, no difference was found in the transferred stress and deformation of the soft tissue. However, displacement was related to a tendency to dehiscence (25% greater in the right-angled/chamfer design). In conclusion different biomechanical behavior was observed in the block graft depending on the design and suture tension, so it is recommended to use low suture tension and rounded design. A novel finite element analysis model is presented for future investigations.

Differences in the shape and direction-course of the nasopalatine canal among dentate, partially edentulous and completely edentulous subjects.

We aimed to analyze the nasopalatine canal shape and anatomical variations of the buccal bone wall and compare the effect of the presence or absence of the central maxillary incisors on the nasopalatine canal. The shape of the nasopalatine canal and the dimensions of the buccal bone wall were measured in 150 patients who underwent a cone-beam computed tomography study. We found that the most prevalent shape of the nasopalatine canal was funnel (31%) and the most common direction-course was slanted-straight (33%). The buccal bone wall in relation to the nasopalatine canal was thickest at the anterior nasal spine level and narrowest at the level of the most anterior-inferior point of the buccal cortex of the maxilla. A statistically significant difference was detected between morphology and direction-course of the nasopalatine canal and dental status. In sum, the study of the nasopalatine canal showed multiple variations. Precise knowledge of these variations may help to decrease the incidence of complications during implantology treatment and during facial and dental surgery.