Effects of gripping volume in the mechanical strengths of orthodontic mini‐implant

Abstract

The objective of study was to investigate the correlation between the mechanical strengths [insertion torque (IT); resonance frequency (RF); and horizontal pullout strength (HPS)] and gripping volume (GV) of mini-implants. Thirty mini-implants of three types (Type A: 2 mm × 10 mm, cylindrical, titanium alloy; Type B: 2 mm × 10 mm, tapered, stainless steel; and Type C: 2 mm × 11 mm, cylindrical, titanium alloy) were inserted 7 mm into artificial bones. One-way analysis of variance and Spearman's test were applied to assess intergroup comparisons and intragroup correlations. The null hypothesis was that no statistically significant correlations exist between the GV and mechanical strengths (IT, RF, and HPS). In the IT test, Type C (14.2 Ncm) had significantly (p=0.016) greater values than did Type A (12.4 Ncm). In the RF analysis, no significant difference was observed among the three types of mini-implants. In the HPS test, Type C (388.9 Ncm) was significantly larger than both Type B (294.5 Ncm) and Type A (286 Ncm). In the GV measurement, Type C (14.4 mm) was significantly larger than Type B (11.4 mm) and Type A (9.2 mm). Type A and Type B exhibited no significant correlations among the tests. Therefore, the null hypothesis was accepted. Although no significant correlation was noted between the GV and mechanical strengths (IT, RF, and HPS), we observed a trend that the mechanical strengths (IT, RF, and HPS) of the mini-implants corresponded to the order and values of GV (Type C > Type B > Type A).

Sex-, growth pattern-, and growth status-related variability in maxillary and mandibular buccal cortical thickness and density

“…The principal determinants for mini-implant stability are mechanical retention, mini-implant design, quality and quantity of bone, and placement technique. 10 The firmness of cortical bone is one of the primary factors controlling the stability of mini-implants. 11 Several researchers have attempted to study cortical bone thickness to predict the stability of mini-implants.…”

Computed Tomographic Evaluation of Buccal Shelf Dimensions in South Indian Patients With Sagittal Skeletal Class III Malocclusion: A Retrospective Study

“…According to the Misch classification for implant placement, the MBS region has a dense cortical bone (D2), with an implant success rate of up to 90%, thus proving to be a popular treatment modality [ 7 ]. It is reported that the most significant factors in predicting MS stability include bone thickness, mechanical retention, screw design, and placement technique [ 8 ]. Motoyoshi et al reported that MS had a higher success rate when placed in an area with cortical bone thickness (CBT) ≥ 1 mm [ 9 ].…”

Finite element simulation and statistical investigation of an orthodontic mini-implant’s stability in a novel screw design

“…1 The clinical success in the use of mini-implants is above 80% 2 ; however, failure cases are reported. 3 Many unsuccessful uses of mini-implants appear in the very early stages of placement and loading. Therefore, the primary stability is very crucial.…”

“…However, they have little effect on the created strains, and damage the bone by increasing the stresses around it. 3,8 The changes in the mini-implant design should be made with caution because the mechanical methods of controlling the stability are not accurate. 9,10 To solve this problem non-destructive mechanical methods such as FE analysis are used.…”