Intrusion Effects on Maxillary Anteriors using Mini Implant Anchorage and K-Sir Loop in Subjects with Deep Overbite- A Cohort Study

Abstract

Introduction: Various options to treat deep bites nonsurgically involve extrusion of posterior teeth or intrusion of anterior teeth. Intrusion of anterior teeth is required in patients with excessive incisal display and to correct deep bite in adult patients when extrusion of posterior teeth is not desirable. Aim: To compare the rate of intrusion and dento-alveolar effects on maxillary anterior teeth by Kalra-Simultaneous Intrusion and Retraction loop (K-SIR loop) and Mini implant anchorage in subjects with deep overbite. Materials and Methods: This prospective cohort study included 12 patients with Class I or Class II Div 1 malocclusion having an overbite and overjet of >4 mm treated with therapeutic extractions of upper first premolars. Group A included six subjects treated using orthodontic Mini implants, while Group B had six subjects treated with K-SIR loop. Lateral cephalograms were taken before intrusion and retraction (T1) and at the end of six months (T2) into intrusion and retraction. Independent t-test and paired t-test was done for intergroup and intragroup comparison respectively. Results: The rate of intrusion was 0.38 mm/month and 0.31 mm/month for Group A and Group B, respectively. The amount of intrusion was significantly more in Temporary Anchorage Devices (TAD) group (p-value <0.01). Conclusion: In the TAD group, rate and amount of intrusion was significantly higher. There is no difference in vertical control between the two modalities statistically significant amount of molar extrusion was seen with the K-SIR loop group.

The Effects of Intrusion of Anterior Teeth by Skeletal Anchorage in Deep Bite Patients; A Systematic Review and Meta-Analysis

“…The full text of the remaining 30 studies (21 studies by database search and 9 studies after manual search) were retrieved and analyzed, 5 of them because only the amount of vertical control of teeth during retraction was assessed and 10 of them were excluded because they did not have a mini-screw group. A total of 15 articles were included in our study for systematic review [ 15 , 29 , 30 , 31 , 32 , 33 , 34 , 36 , 37 , 38 , 39 , 40 , 41 , 42 ], and after data extraction, meta-analyses were performed on 14 studies, and for one study [ 42 ], only a systematic review was performed due to differences in outcomes and retainers under review with the rest of the studies.…”

“…In all these studies except the study by El Namrawy et al [ 31 ], the time required for intrusion in the TAD group was less or equal to the comparison groups, while in the study by El Namrawy et al, the time required to obtain a suitable overbite was non-significantly higher for the mini-screw group. Regarding the rate of intrusion, in two studies the rate of intrusion in the TAD group compared with comparison groups was significantly higher (Gupta et al, Polat -Ozsoy et al), and in two studies, it was slightly higher (Senisik et al, Verma et al) [ 30 , 33 , 34 , 36 ].…”

“…Research has shown that mini-screws have the ability to apply force up to 500 g and at the same time remain intact until the end of the treatment [ 27 ]. The potential advantages of the TAD system are the possibility of applying force to the goal of tooth displacement in any direction, in the absence of mutually destructive forces, with no need for patient cooperation, and the possibility of changing the position and inclination of the upper and lower incisors to the desired state with the possibility of inserting incisors with minimal protrusion, higher intrusion speed, and no effect on posterior teeth [ 28 , 29 , 30 ] ( Figure 1 c).…”

“…Several different studies have reported conflicting results for the advantages of TADs compared to other common treatment methods for anterior teeth intrusion regarding the intrusion speed, the amount of true intrusion, the effects on incisor inclination and the effects on posterior teeth [ 30 , 31 , 32 , 33 , 34 ]. Because of this, we intend to investigate the effects of intrusion of anterior teeth by skeletal anchorage in deep bite patients in this systematic review and meta-analysis.…”

Two simple yet efficient biomechanics for correction of retroclined maxillary central incisors

“…[1][2][3] K sir loop is also one of the treatment modality for simultaneous intrusion and retraction of maxillary anterior teeth. 4 According to Newton's third law of motion, any of these mechanics generates equal and opposite reactive force which may cause unwanted tooth movement of posterior teeth and adjacent teeth like lateral incisor. The advent of Temporary anchorage devices (TADS) has proved to be a boon for orthodontists.…”