Class II malocclusion
Conditions
Interventions
Experimental group:Class II elastics on both sides with 1/4‘’ 3.5oz of force
Control group:Class II elastics on both sides with 5/16‘’ 3.5oz of force
Sponsors
Nanjing Stomatological Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, China
Eligibility
Sex/Gender
All
Age
16 Years to 30 Years
Inclusion criteria
Inclusion criteria: 1) Use clear aligner throughout the treatment process; (2) Permanent occlusion, with four second molars fully erupted and established; (3) Complete dentition, no abnormal missing teeth or supernumerary teeth; (4) Preoperative extraction of the third molar; (5) The relationship between molars is Class II, and the orthodontic plan requires the design of distal displacement of maxillary molars; (6) The maxillary molars are not designed with other tooth movement methods such as compression, elongation, rotation, etc; (7) The anterior teeth are not designed to move during the process of distant molar movement; (8) The hard palate is well developed, with clear morphology of palatal folds and no cleft palate; (9) The patient has good compliance, with an average daily time of wearing an invisible appliance of = 22 hours; (10) Good oral hygiene, good periodontal condition, and no obvious gingival recession.
Exclusion criteria
Exclusion criteria: (1) Patients with poor compliance and less than 10 hours of daily appliance wear, or each appliance wear for less than 10 days; (2) During the orthodontic treatment process, the orthodontic device may not fit the teeth due to poor patient compliance or various other reasons, resulting in a redesign of the plan; (3) Those who do not cooperate with Class II traction during the stage of distant molars and premolars; (4) During the correction process, observe the changes in the position and morphology of teeth and palatal folds due to trauma and other reasons; (5) Observing the changes in the shape and height of the tooth tip during the orthodontic treatment process, as well as the extensive adjustment of the teeth; (6) Those who have the habit of grinding and clenching their teeth at night.
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| molar distalization efficiency;root length; | — |
Secondary
| Measure | Time frame |
|---|---|
| Height of alveolar Bone resorption;Alveolar bone area; | — |
Countries
China
Contacts
Public ContactLang Lei
Nanjing Stomatological Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, China
Outcome results
None listed