The Bone Buttress Theory: The Effect of the Mechanical Loading of Bone on the Osseointegration of Dental Implants

Abstract

Objectives: To determine the effect of mechanical loading of bone on the stability and histomorphometric variables of the osseointegration of dental implants using an experimental test in an animal model. Materials and Methods: A total of 4 human implants were placed in both tibiae of 10 New Zealand rabbits (n = 40). A 6-week osseointegration was considered, and the rabbits were randomly assigned to two groups: Group A (Test group) included 5 rabbits that ran on a treadmill for 20 min daily during the osseointegration period; Group B (Controls) included the other 5 that were housed conventionally. The monitored variables were related to the primary and secondary stability of the dental implants (implant stability quotient—ISQ), vertical bone growth, bone to implant contact (BIC), area of regenerated bone and the percentage of immature matrix. Results: The results of the study show a greater vertical bone growth (Group A 1.26 ± 0.48 mm, Group B 0.32 ± 0.47 mm, p < 0.001), higher ISQ values (Group A 11.25 ± 6.10 ISQ, 15.73%; Group B 5.80 ± 5.97 ISQ, 7.99%, p = 0.006) and a higher BIC (Group A 19.37%, Group B 23.60%, p = 0.0058) for implants in the test group, with statistically significant differences. A higher percentage of immature bone matrix was observed for implants in the control group (20.68 ± 9.53) than those in the test group (15.38 ± 8.84) (p = 0.108). A larger area of regenerated bone was also observed for the test implants (Group A 280.50 ± 125.40 mm2, Group B 228.00 ± 141.40 mm2), but it was not statistically significant (p = 0.121). Conclusions: The mechanical loading of bone improves the stability and the histomorphometric variables of the osseointegration of dental implants.

Finite Element Analysis of Stress in Anterior Prosthetic Rehabilitation with Zirconia Implants with and without Cantilever

“…Thus, differences found between the results of current study and the literature can also be explained by the intensity and inclination of the load, since different loads form different lever arms in monotype zirconia implants, increasing the stresses in the regions of rotational fulcrum and bone crest. 5,20,[25][26][27][28] Furthermore, the results of this study (monotype zirconia implant) showed lower stress values than several studies 2,3,17,24,29 that used titanium implants. The highest Young's Modulus for zirconia (200 GPa; ►Table 1) in relation to the titanium (115 GPa) 29 could explain this difference.…”

“…Fig. 2 Vestibular view of the implants showing the distribution of the maximum principal stress on the implants in the groups (A) Zr (11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21), (B) Zr (12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22), and (C) Zr (11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22).…”

“…Zr (11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22): intercalated implants in regions 11 and 22. The implants were positioned parallel to their long axis on the bone base from tomography, and the implant platform was positioned at the height of the bone crest with standardization of the bone ridge.…”

“…Finite element analysis (FEA) is used in Dentistry to study how an implant and prosthodontics structures will respond to complex stress loading and to predict any possibility of structural failure. 2,9,[11][12][13][14] Thus, the aim of the present study was to verify the stress distribution in the implant, crown, and bone tissue in zirconia implants (single-body configuration) placed in different positions in the anterior region of the maxilla (12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22) in rehabilitation with and without a cantilever. The tested hypothesis is that implants placed on central incisors (11-21; with cantilever) would have lower mechanical performance compared with the other groups.…”

Uso do guia multifuncional para ganho de previsibilidade em protocolo de carga imediata inferior sobre implantes

“…No controlled studies have been found evaluating the influence on periimplant health of placing implants immediately following tooth extraction or after allowing socket healing in patients rehabilitated with fixed full-arch prostheses. (Den Hartog, Huddleston Slater, Vissink, Meijer, & Raghoebar, 2008) (Lang, Pun, Lau, Li, & Wong, 2012) (Chavarri-Prado et al, 2021 Crespi et al, evaluated changes in the bone around 40 immediate implants, 20 immediately restored and 20 loaded after three months. The authors reported a success rate of 100% in both groups, and radiographic results were similar.…”