Comparative evaluation of micro-implant and headgear anchorage used with a pre-adjusted appliance system

Abstract

The aim of this study was to compare and evaluate the anchorage effectiveness of using either micro-implants or extraoral headgear with the McLaughlin-Bennett-Trevisi (MBT) system. Thirty young Chinese adults (14 males and 16 females) aged 18-22 years with anterior bimaxillary protrusion were divided randomly into two equal groups, treated with the MBT system anchored by either micro-implants or headgear. Nine measurements obtained before and after treatment from lateral cephalometric radiographs were assessed for the two groups, using the Mann-Whitney U test with alpha = 0.05 for statistical significance. The maxillary incisors in the micro-implant group were significantly more retracted and intruded, while the lower incisors were more lingually inclined, than in the headgear group. The occlusal and mandibular planes were rotated more counterclockwise in the micro-implant group than in the headgear group (P < 0.05). Compared with headgear anchorage, micro-implant anchorage may counteract clockwise rotation of the occlusal and mandibular planes and result in different final positions for the maxillary and mandibular incisors.

Effect of retraction of anterior teeth on pharyngeal airway and hyoid bone position in Class I bimaxillary dentoalveolar protrusion

“…The cephalometric findings usually show an increased horizontal distance from the most protrusive point of upper lip to esthetic line, horizontal distance from the most protrusive point of lower lip -esthetic line, angle between the Frankfort horizontal plane and long axis of upper incisor, and angle between the mandibular plane and long axis of lower incisor. 1 Orthodontic treatment usually indicates extraction of four first premolars followed by retraction of anterior teeth in the extraction space. 2 Studies [1][2][3][4][5][6][7][8] have been carried out in the past to evaluate the relationship between pharyngeal airway and skeletal, dental parameters, soft tissue matrix including musculature, and growth patterns.…”

“…1 Orthodontic treatment usually indicates extraction of four first premolars followed by retraction of anterior teeth in the extraction space. 2 Studies [1][2][3][4][5][6][7][8] have been carried out in the past to evaluate the relationship between pharyngeal airway and skeletal, dental parameters, soft tissue matrix including musculature, and growth patterns. It has been seen in the past that tongue position changed in the oral environment after mandibular setback by sagittal split ramus osteotomy.…”

Changes of pharyngeal airway size and hyoid bone position following orthodontic treatment of Class I bimaxillary protrusion

“…Cephalometric analysis generally shows an increased UL-E line, LL-E line, U1/FH, and L1/MP value. 1 The negative perception of protruding lips and protrusive dentitions often leads such patients to seek orthodontic care to decrease protrusion and improve profile. For this objective, four premolars are often extracted to create room for retraction of anterior teeth, 2 which changes not only tooth position but also hard and soft tissue components.…”

Impact of anchorage miniscrews in multibracket treatments without extractions

“…Their potential has been demonstrated repeatedly during multibracket treatments for mesial movements 3,23 , for molar distalization 25,53,61,62 , for intrusion 18,64,65 , for extrusion 10,12 , for ''in masse'' retraction of anterior teeth 19,57,69 , or for maintaining anchorage in cases of premolar extractions 35,39,44 . A recent meta-analysis provides an update on their results compared to those obtained with extraoral force 43 and demonstrates greater anterior retraction and less loss of posterior anchorage with miniscrews.…”

“…Since the very first clinical articles 56,70 , a great number of other treated cases have been published with sometimes outstanding results 1,2,[31][32][33]36,52,57,66,67 . The list of comparative studies 7,21,30,39,44 , experimental studies 26,45,51 , some randomized clinical trials 7,35,38,71 and systematic reviews 14,16,20,22,43 has continued to grow over the years. This can be seen as evidence for an ongoing therapeutic revolution that is impacting all aspects of orthodontics and that is suggesting new solutions for the buccal technique 8,15,28,34,36,46,55 as well as for lingual orthodontics 4,29,37,41,69 , for the aligner technique 11,73 or for orthopaedics 13 .…”