Effect of microthreads on removal torque and bone-to-implant contact: an experimental study in miniature pigs

Abstract

PurposeThe objective of this study was to evaluate the effect of microthreads on removal torque and bone-to-implant contact (BIC).MethodsTwelve miniature pigs for each experiment, a total of 24 animals, were used. In the removal torque analysis, each animal received 2 types of implants in each tibia, which were treated with sandblasting and acid etching but with or without microthreads at the marginal portion. The animals were sacrificed after 4, 8, or 12 weeks of healing. Each subgroup consisted of 4 animals, and the tibias were extracted and removal torque was measured. In the BIC analysis, each animal received 3 types of implants. Two types of implants were used for the removal torque test and another type of implant served as the control. The BIC experiment was conducted in the mandible of the animals. The P1-M1 teeth were extracted, and after a 4-month healing period, 3 each of the 2 types of implants were placed, with one type on each side of the mandible, for a total of 6 implants per animal. The animals were sacrificed after a 2-, 4-, or 8-week healing period. Each subgroup consisted of 4 animals. The mandibles were extracted, specimens were processed, and BIC was analyzed.ResultsNo significant difference in removal torque value or BIC was found between implants with and without microthreads. The removal torque value increased between 4 and 8 weeks of healing for both types of implants, but there was no significant difference between 8 and 12 weeks. The percentage of BIC increased between 2 and 4 weeks for all types of implants, but there was no significant difference between 4 and 8 weeks.ConclusionsThe existence of microthreads was not a significant factor in mechanical and histological stability.

The Effect of Coronal Implant Design and Drilling Protocol on Bone-to-Implant Contact: A 3-Month Study in the Minipig Calvarium

“…The measured BIC of implants inserted according to DP1 and DP2 was comparable for all of the implant types after both 1 m and 3 m of healing for each drilling protocol and ranged from 75-96% after 3 m without significant differences among the implant types or between the drilling protocols. The reported BIC is in agreement with that in a study conducted by Kwon, who reported that the BIC of implants inserted in minipigs ranged from 71-82% after 1 m of healing [32].…”

Influence of cortical thickness on the stability of mini-implants with microthreads

“…This makes it possible to distribute the stress more evenly, increasing MI stability. 19,20 Kwon et al 19 did not find significant mechanical and histological differences, in terms of removal torque and bone/implant contact, when comparing implants with and without microthreads. However, Chang et al, 20 using mechanical and finite element analysis, concluded that modification of MI design can affect mechanical properties, improving primary stability.…”

Osseoconductivity of a Specific Streptavidin–Biotin–Fibronectin Surface Coating of Biotinylated Titanium Implants – A Rabbit Animal Study

“…The case number was planned to be equal if not higher than in current similar studies comparing titanium implant surfaces in vivo. [35][36][37] For evaluation, a total of 84 implants (uncoated, n = 36; streptavidin-biotin, n = 24; and streptavidin-biotin-fibronectin, n = 24) were available. Half of them were analyzed after 3, the other half after 6 weeks.…”