Measurement of Primary Stability of Mini Implants Using Resonance Frequency Analysis

Abstract

Introduction In the last decade, anchorage control with mini-implants has gained enormous credibility in maintaining orthodontic anchorage. Resonance frequency analysis (RFA) has proven to be an adequate method to measure the stability of these mini-implants because of its non-invasiveness and contactless measurement method. Materials and Method Tomas and S.K surgical mini-implants were tested. For this purpose custom fabricated attachment was fabricated to attach the smart peg on orthodontic mini-implant head, and 45 mini-implants were inserted in fresh swine pelvic bone in the density matched sites to that of most common sites where mini-implants are placed in human mandible. Mini-implants of two different lengths with diameter constant were also placed to assess the effect of length on primary stability. Results The mean ISQ of Group 1 (Tomas 10 mm) was 55.53±3.39 while that of Group 2 (S.K Surgical 10mm) was 56.63±3.48 and that of Group 3(S.K Surgical 8 mm) was 55.90±3.48. Difference among the groups were not statistically significant when ANOVA test was used (P >0.05). Conclusion The resonance frequency analysis is applicable to comparatively assess the primary stability of orthodontic mini-implants. There was no difference in primary stability of Tomas and S.K Surgical mini-implant and primary stability was not affected by the length of the mini-implant.

In-vitro investigation of primary stability of orthodontic mini implants with different lengths using resonance frequency analysis

“…However, the results of this study are in contrast with study done by Singh AK et al, 5 Song et al 21 and Neinkemper et al 22 They concluded that primary stability of mini implants is not affected by changes in length of mini implant. These differences in results found may be due to variation in brands of implants used, 5 or changes in diameter along with length of implants studied.…”

“…However, the results of this study are in contrast with study done by Singh AK et al, 5 Song et al 21 and Neinkemper et al 22 They concluded that primary stability of mini implants is not affected by changes in length of mini implant. These differences in results found may be due to variation in brands of implants used, 5 or changes in diameter along with length of implants studied. 21 In this study, we selected constant diameter and brand for both the groups to prevent any changes in surface morphology, only factor that was altered was the length of the implants studied.…”

“…This primary stability comes from mechanical interlocking of threads of implants with the bone. 5 Also, there are various factors which influence the implant stability like insertion angle of implant in the bone, bone physiology, implant size and shape and implant surface characteristics. 6 Out of various bone densities, D2 bone was selected for conducting this study as it is found most commonly in the region where implants are placed in humans for orthodontic anchorage purpose.…”

“…4 The basic requirement for the success of orthodontic mini-implants is sufficient primary stability which comes from mechanical interlocking with the cortical bone when the mini-implant is placed. 5 Primary stability is influenced by bone quality and quantity, surgical technique, and screw geometry (design of the implant, its diameter and length). 6 Bone quality and quantity are important factors since they directly influence the selection of mini implant.…”

Retention of Mini Screws in Orthodontics – a Comparative in Vitro Study on the Variables

“…However, the long mini-implant can fracture during insertion because it needed a higher insertion torque 11 . Contrary to the present study were the results of Singh AK et al 20 and Ohali HA 21 . They stated that an increase in length did not affect the stability of mini-implant.…”