Maxillary Segment Tipping During Transpalatal Distraction

Study Overview
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Brief Summary
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The investigator proposes a multi-centre study to investigate tipping of teeth, bringing into consideration the height of the osteotomy line and the height and placement of the transpalatal distractor as possible factors. If tipping occurs depending on these factors, the investigator could identify the situations that cannot be straightened by the orthodontist and provide another course of action for these specific patients.

Detailed Description
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Surgically Assisted Rapid Maxillary Expansion (SARME) is widely accepted for the treatment of maxillary hypoplasia. The differences between SARME with a tooth-borne or a bone-borne distractor have already been extensively investigated, bringing to light that a bone-borne distractor has less negative side effects. One of the major concerns with the tooth-borne distractor is the tipping of the anchor teeth, which is bypassed by the bone-borne distractor which applies its force directly on the bone. One study investigated the tipping of teeth with a bone-borne distractor in 10 patients, showing that there was a minor change in the tooth axis. The investigator proposes a multi-center study to investigate this tipping further, bringing into consideration the height of the osteotomy line and the height and placement of the transpalatal distractor as possible factors. If tipping occurs depending on these factors, the investigator could identify the situations that cannot be straightened by the orthodontist and provide another course of action for these specific patients.

Official Title
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Is Maxillary Segment Tipping During Transpalatal Distraction Related to the Vertical Level of the Horizontal Corticotomies and the Vertical Position of the Distractor Related to Dental and Bony Reference Planes?

Conditions
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Maxillary Hypoplasia

Intervention / Treatment
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* Other: Conebeam CT


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Undergoing a surgically assisted rapid maxillary expansion with a bone borne transpalatal distractor. Cone beam CT pre op and 3 weeks post op is available Exclusion Criteria: Complication of the process by e.g. surgical site infection Asymmetrical expansion of more than 3.0 mm measured at the central incisivae occurred

Ages Eligible for Study
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Minimum Age: 14 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: Tooth tipping<br> | Other: Conebeam CT<br>* medical imaging technique consisting of X-ray computed tomography where the X-rays are divergent, forming a cone<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Tooth axis | To investigate changes in the tooth axis of the first and second (pre-)molars bilaterally in the upper jaw before and after surgically assisted rapid maxillary expansion using a bone borne transpalatal distractor. | 3 weeks postoperatively | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Transpalatal, Maxillary expansion, Tooth-borne, Bone-borne, Distractor, Tipping, Osteotomy height