American Journal of Orthodontics and Dentofacial Orthopedics
Original articleDistal movement of maxillary molars in nongrowing patients with the skeletal anchorage system
Section snippets
Material and methods
Twenty-five nongrowing patients (22 female, 3 male) who had undergone SAS treatment at Tohoku University Dental Hospital, Sendai, Japan, were selected as subjects in this study. Twenty-two patients were treated by 1 clinician (J.S.), and 3 patients were managed by residents under his supervision. All subjects met the following criteria for case selection: (1) it was cephalometrically confirmed that they were nongrowing at least in terms of the maxillary growth before treatment, (2) there was
Results
Figure 5 is a scattergram of distal movement of the maxillary first-molar crowns and roots of all subjects. It shows the relationship between posterior displacement of the crowns and roots of the maxillay first molars individually. The average amounts of distalization at the crown and the root levels were 3.78 and 3.20 mm, respectively. The maximum crown displacement was 6.8 mm, and the minimum was 1.5 mm. The maximum root distalization was 6.0 mm, and the minimum was 1.3 mm. The correlation
Discussion
The indications for intraoral distalizing appliances that have been previously reported were mostly Class II malocclusions. But the indications for distal movement with the SAS include not only Class II malocclusions but also any malocclusions characterized by crowding of the maxillary dentition and labial inclination of the maxillary incisors in any facial types, because the SAS enables simultaneous 3-dimensional control of the maxillary and mandibular molars.38, 39, 40, 41, 42 Open-bite was a
Conclusions
The SAS is a viable modality for distalizing maxillary molars because it uses stable and strong anchorage units. It enables not only single molar distalization but also en-masse movement of the maxillary buccal segments with only minor surgery for placing the titanium anchor plates at the zygomatic buttresses. Therefore, this new noncompliance technique is particularly useful for correcting Class II malocclusions, decompensation for Class III surgical patients, and malocclusions characterized
References (43)
The effect of force on craniofacial development
Am J Orthod
(1974)- et al.
The use of magnets to move molars distally
Am J Orthod Dentofacial Orthop
(1989) - et al.
Japanese NiTi coils used to move molars distally
Am J Orthod Dentofacial Orthop
(1991) - et al.
Molar and incisor changes with Wilson rapid molar distalization
Am J Orthod Dentofacial Orthop
(1993) - et al.
Case reports: molar distalization with static repelling magnets. Part II
Am J Orthod Dentofacial Orthop
(1995) - et al.
Evaluation of an intraoral maxillary molar distalization technique
Am J Orthod Dentofacial Orthop
(1996) Distal movement of maxillary molars
Am J Orthod Dentofacial Orthop
(1998)- et al.
Dental and skeletal changes after intraoral molar distalization with sectional jig assembly
Am J Orthod Dentofacial Orthop
(1998) - et al.
Analysis of rapid maxillary molar distal movement without patient cooperation
Am J Orthod Dentofacial Orthop
(1999) - et al.
Dentoalveolar and skeletal changes associated with the pendulum appliance
Am J Orthod Dentofacial Orthop
(2000)