Influence of Different Porosities of Titanium Meshes on Bone Neoformation: Pre-Clinical Animal Study with Microtomographic and Histomorphometric Evaluation

The aim of this study was to evaluate the influence of different types of porosity of titanium meshes on the bone neoformation process in critical defects surgically created in rat calvaria, by means of microtomographic and histomorphometric analyses. Defects of 5 mm in diameter were created in the calvaria of 36 rats, and the animals were randomly treated and divided into the following groups (6 animals per group): NCOG (negative control, only blood clot), TEMG (Polytetrafluoroethylene—PTFE—membrane), SPTMG (small pore titanium mesh), SPMMG (small pore mesh + PTFE), LPTMG (large pore titanium mesh), and LPMMG (large pore mesh + PTFE). After 60 days, the animals were sacrificed, and the bone tissue formed was evaluated with micro-CT and histomorphometry. The data were compared using an ANOVA followed by the Tukey post-test (p ≤ 0.05). The microtomographic results showed that the SPTMG group presented the highest numerical value for bone volume/total volume (22.24 ± 8.97), with statistically significant differences for all the other groups except LPTMG. Considering the histomorphometric evaluation, groups with only porous titanium meshes showed higher values compared to the groups that used the PTFE membrane and the negative control. The SPTMG group presented higher values in the parameters of area (0.44 mm² ± 0.06), extension (1.19 mm² ± 0.12), and percentage (7.56 ± 1.45%) of neoformed bone. It was concluded that titanium mesh with smaller pores showed better results and that the association of PTFE membranes with titanium meshes did not improve the outcomes, suggesting a correlation between mesh porosity and underlying bone repair.