Stability of Bimaxillary Proclination Cases Following Fixed Appliances Treatment: A Randomized Control Trial

University of Malaya27 enrolled

Overview

Bimaxillary dental proclination is the condition where the upper and lower dental arches are procline thus increase lip fullness. Since the aim of orthodontic treatment in bimaxillary proclination in to get flatten profile where the incisor inclinations are purposely reduced or interincisal angle are increased, therefore it is guarded for corrected dentition to maintain stable or not post orthodontic treatment.Therefore, this study is looking into evidence which is the best retainer to maintain stability of bimaxillary proclination cases following fixed appliances treatment.

Study title Stability of Bimaxillary Proclination Cases Following Fixed Appliances Treatment: A Randomized Control Trial Study Population Pre-treatment of bimaxillary proclination patient who completed active orthodontic treatment with fixed appliances and are scheduled to debond at Orthodontic Clinic, Faculty of Dentistry, University of Malaya. Study Design Randomized, prospective, single-center control trial. Three parallel arm groups of patients will be assigned for 3 types of retention methods; 1.VFR 2.Fixed bonded retainer 3.Double regime (bonded \& VFR) Aim of study To determine the best mode of retention to maintain the stability of bimaxillary proclination cases treated by four premolars extraction and fixed appliances. Specific Objectives 1. To measure the post treatment dental and soft tissue stability in the retention phase up to one-year post treatment 2. To compare the effectiveness the different types of retainers to maintain the stability of orthodontically corrected bimaxillary proclination 3. To determine the impact of the different types of retainers on the OHRQoL Sample Size The sample size calculation was done using G\*power software version 3.1.The f-test, repeated measures ANOVA, within-between interaction were used. Based on the effect size of 0.43 (Keating PJ 1986), maximum accuracy (power) of 80% (0.80), error of 5% (0.05), number of groups are 3, number of measurements are 2, correlation among repetitive measures is 0.5, nonsphericity correlation is 1, total number of 18 subjects needed for entire study. Allowing for 50% dropout, a final sample size of 27 subjects with 9 subjects per group will be used. Study Duration September 2019 - Disember 2021

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Interventions

Vacuum formed retainer, fixed bonded retainer, vacuum formed and fixed bonded retainerOTHER

Patients will be instructed to wear the removable vacuum form retainer for 8 to 10 hours per day and only removed the retainers during tooth brushing. (Thickett 2010), (Gill 2007). The vacuum formed retainer will be constructed using thermoplastic material that will be purchased from manufacturer at 1.0mm thickness. Meanwhile, bonded retainer will be done using Ormco ® response deadsoft retainer wire size 0.190 round, made in USA by ORMCO Corporation, the fixed bonded wire will be extended distal to the extraction spaces that were previously closed by fixed appliances on both the upper and lower arches. The bonded retainer will be wearing by patients for 24 hours. Double regime retainer that will be comprised of vacuum formed and bonded retainer will be constructed using the same properties as vacuum formed retainer and bonded retainer. A standard oral and written instruction will be given to patients regarding retainer's uses. (Shawesh M et.al, 2009).

Eligibility

Sex: ALLHealthy volunteers:

Medical Language ↔ Plain English

Inclusion Criteria: 1. Pretreatment bimaxillary proclination patients with interincisal angle less than 125º (Keating PJ 1986). 2. Patients with fixed orthodontic appliances treatment on both arches consisting of the extraction of 4 premolars (Keating 1986). 3. Both arches are indicated for retainers. 4. Pre-treatment lateral cephalometric radiograph of adequate diagnostic quality. Exclusion Criteria: 1. Pretreatment spacing eg: Median diastema. 2. No change or proclined lower labial segment post treatment. 3. Early debond patient. 4. Patient intended to relocate within study period. 5. Hypodontia that require prosthesis, cleft lip and/or cleft palate, or orthognathic cases. 6. Patients with learning disabilities and unable to listen, speak and read written instructions in Bahasa Melayu or English.

Outcomes

Primary Outcomes

Stability: Change in the incisal inclinations

To measure any changes in the upper incisor to maxillary plane angle, lower incisor to mandibular plane angle and changes in interincisal angle. This angular measurement will be measured in degree.