This trial is active, not recruiting.

Condition jaw abnormalities
Sponsor AZ Sint-Jan AV
Start date November 2014
End date March 2016
Trial size 20 participants
Trial identifier NCT02660216, BO49201525495


Nowadays, maxillary Le Fort I osteotomy is a safe and routinely performed procedure. The conventional approach is characterized by a vestibular incision extending from molar-to-molar, associated with a pterygomaxillary disjunction performed with a curved chisel. Adequate mobilization of the maxilla during Le Fort I osteotomy requires an effective separation of the maxillary tuberosity from the pterygoid plates of the sphenoid bone. However, as initially described by Precious (1991) and later by Hernandez-Alfaro (2013), a true pterygomaxillary osteotomy is not necessary to achieve successful disjunction. Furthermore, Hernandez-Alfaro combined his technique of pterygomaxillary disjunction, the so-called "Twist technique", to a minimally invasive protocol, performing the complete Le Fort I osteotomy through a 20 to 30 mm long horizontal vestibular incision. Although promising, the technique remains highly sensitive from a technical standpoint, and its true accuracy has not been comprehensively evaluated.

The purpose of this study is to present and validate a minimally invasive approach towards Le Fort I osteotomy, using a modified pterygomaxillary (PTM) disjunction technique. The primary outcome is to evaluate the accuracy of the technique using rigid voxel-based registration of the 3D virtual treatment planning and the 4 weeks postoperative CBCT images. Secondary outcomes include the surgical time necessary to complete the procedure and the presence of intraoperative and early postoperative complications.

United States No locations recruiting
Other Countries No locations recruiting

Study Design

Observational model cohort
Time perspective prospective

Primary Outcomes

accuracy of the minimally invasive approach in comparison to conventional approaches, based on 3D virtual CBCT superimposition of planning CBCT and postoperative CBCT
time frame: at 4 weeks postoperative

Secondary Outcomes

Surgical time necessary to complete the procedure
time frame: perioperative
Intraoperative and early postoperative complications
time frame: within 4 weeks postoperative

Eligibility Criteria

Male or female participants of any age.

Inclusion Criteria: - Patients of all ages - Patients of all genders - A Le Fort I osteotomy is planned, as part of a bimaxillary orthognathic procedure - The surgery is planned with 3D Virtual Treatment Planning (Maxilim v. - The planning is transferred with 3D CAD/CAM tooth-borne splint and vertical internal bony reference landmarks - The maxilla is repositioned first during the surgery (maxilla first sequence) Exclusion Criteria: - Patients not eligible according to abovementioned criteria - Simultaneous extraction of impacted teeth 18 and/or 28 - Previous maxillary orthognathic surgery - Previous Surgical Assisted Rapid Palatal Expansion (SARPE) - Syndromic condition, including cleft lip and palate - Segmental Le Fort I osteotomy - Adjuvant Zygomatic osteotomy - Maxillary impaction higher than 3 mm - Maxillary advancement greater than 5 mm

Additional Information

Principal investigator Gwen Swennen
Trial information was received from ClinicalTrials.gov and was last updated in January 2016.
Information provided to ClinicalTrials.gov by AZ Sint-Jan AV.