Clinical trial NCT02865213: Molar Intrusion in Open Bite Treatment
Official title: Assessment of Skeletal and Dentoalveolar Changes Resulting From Posterior Teeth Intrusion in Treatment of the Anterior Open Bite - a Randomized Controlled Trial
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Anterior Open Bite
Keywords: Open bite
Molar intrusion
Temporary anchorage devices
Lead sponsor: Damascus University
Sponsor class: OTHER
First posted: 2016-08-12
Enrollment: 45
Sex: ALL
Minimum age (years): 12
Maximum age (years): 18
Standard ages: CHILD
ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: TREATMENT

Brief summary: This experimental study will evaluate the effect of different methods for the molar intrusion (compared with the control group) in adolescent and adult patients with open bite malocclusion. The study sample will consist of 45 patients with anterior open bite. The sample will be randomly allocated into two experimental groups, in addition to a control group.

The investigators will apply a modified version of the Open Bite Appliance (OBA), by Erverdi and Usumez, for all patients in upper posterior teeth. For this purpose, miniplates will be used in the first treatment group, while miniscrews will be used in the second treatment group. In the control group, only OBA will be used. The skeletal and dentoalveolar changes occurring after intrusion of posterior teeth will be assessed by using posteroanterior and lateral cephalometric radiographs. Pre- and post- treatment changes for each group will be evaluated, in addition to the comparison of the post-treatment skeletal and dental changes that occurs between groups.

Detailed description: Open bite malocclusion is considered one of the most difficult orthodontic problems to correct because it appears as a result of the interaction of numerous etiological factors (genetic, dental, skeletal, functional, soft tissue, and habit) that contribute to its development. Various therapeutic approaches have been proposed for the treatment of an anterior open bite. These approaches vary depending on the causative factors and involve myotherapy, preventive treatment, functional therapy, orthognathic surgery, and orthodontic treatment using anterior teeth extrusion or posterior teeth intrusion. Among the non-surgical orthodontic treatment methods are the temporary anchorage devices (TADs) including miniplates and miniscrew or micro-screw implants. The intrusion of posterior teeth with temporary anchorage devices was suggested to lead to decreased lower facial height by a counterclockwise rotation of the mandible; this may resemble the orthognathic surgery outcomes for any open bite patients. To the best of the investigators current knowledge, this is the first randomized controlled trial evaluating the effect of molar intrusion in adolescence and adult patients in the permanent dentition stage.

Eligibility criteria: Inclusion Criteria:

* Patients with skeletal open bite determined by an increased B angle (angle between the maxillary plane and mandibular plane), the Sum of Bjork and the mandibular plane angle (angle between SN plane and mandibular plane).
* Patients between 12 and 18 years old in permanent dentition stage.
* Negative over-bite of more than a mm
* Class I or Class II skeletal anteroposterior relationship.

Exclusion Criteria:

* Previous orthodontic treatment.
* Patients with syndromes, clefts, or craniofacial abnormalities.
* Class III skeletal anteroposterior relationship.

Primary outcomes:
measure: Overbite
timeFrame: This variable will be evaluated twice; T0 before treatment, and T1 at the end of molar intrusion which will be approximately after 7 months
Secondary outcomes:
measure: Molar intrusion
timeFrame: This variable will be evaluated twice; T0 before treatment, and T1 at the end of molar intrusion which will be approximately after 7 months
measure: Mandibular autorotation
timeFrame: This variable will be evaluated twice; T0 before treatment, and T1 at the end of molar intrusion which will be approximately after 7 months
measure: Anterior facial height
timeFrame: This variable will be evaluated twice; T0 before treatment, and T1 at the end of molar intrusion which will be approximately after 7 months
measure: Change in the anteroposterior position of the point "B"
timeFrame: This variable will be evaluated twice; T0 before treatment, and T1 at the end of molar intrusion which will be approximately after 7 months
Other outcomes:
Locations:
city: Damascus
country: Syrian Arab Republic
facility: Damascus University
Study officials:
affiliation: Damascus University
name: Mohamad Yousef, DDS MSc PhD
role: STUDY_CHAIR
References:
citation: Ng J, Major PW, Flores-Mir C. True molar intrusion attained during orthodontic treatment: a systematic review. Am J Orthod Dentofacial Orthop. 2006 Dec;130(6):709-14. doi: 10.1016/j.ajodo.2005.05.049.
citation: Sugawara J, Baik UB, Umemori M, Takahashi I, Nagasaka H, Kawamura H, Mitani H. Treatment and posttreatment dentoalveolar changes following intrusion of mandibular molars with application of a skeletal anchorage system (SAS) for open bite correction. Int J Adult Orthodon Orthognath Surg. 2002;17(4):243-53.
citation: Deguchi T, Kurosaka H, Oikawa H, Kuroda S, Takahashi I, Yamashiro T, Takano-Yamamoto T. Comparison of orthodontic treatment outcomes in adults with skeletal open bite between conventional edgewise treatment and implant-anchored orthodontics. Am J Orthod Dentofacial Orthop. 2011 Apr;139(4 Suppl):S60-8. doi: 10.1016/j.ajodo.2009.04.029.
citation: Akan S, Kocadereli I, Aktas A, Tasar F. Effects of maxillary molar intrusion with zygomatic anchorage on the stomatognathic system in anterior open bite patients. Eur J Orthod. 2013 Feb;35(1):93-102. doi: 10.1093/ejo/cjr081. Epub 2011 Aug 9.
citation: Xun C, Zeng X, Wang X. Microscrew anchorage in skeletal anterior open-bite treatment. Angle Orthod. 2007 Jan;77(1):47-56. doi: 10.2319/010906-14R.1.
citation: Erverdi N, Keles A, Nanda R. The use of skeletal anchorage in open bite treatment: a cephalometric evaluation. Angle Orthod. 2004 Jun;74(3):381-90. doi: 10.1043/0003-3219(2004)0742.0.CO;2.
citation: Hart TR, Cousley RR, Fishman LS, Tallents RH. Dentoskeletal changes following mini-implant molar intrusion in anterior open bite patients. Angle Orthod. 2015 Nov;85(6):941-8. doi: 10.2319/090514-625.1. Epub 2014 Dec 22.
citation: Kuroda S, Katayama A, Takano-Yamamoto T. Severe anterior open-bite case treated using titanium screw anchorage. Angle Orthod. 2004 Aug;74(4):558-67. doi: 10.1043/0003-3219(2004)0742.0.CO;2.