Clinical and Radiographic Evaluation of Low Sagittal Medial Ramus Osteotomy for Treatment of Skeletal Class II and Class III Malocclusion

NCT07746700 | Not Yet Recruiting

• 1 other identifier: 1345/3938
• Study Type: interventional
• Target: 11
• Locations: 0 countries
• Sites: N/A

Brief Summary

This prospective clinical trial aims to evaluate the clinical and radiographic outcomes of the low sagittal medial ramus osteotomy-a technical modification of the conventional sagittal split osteotomy (SSO)-for treating patients with skeletal Class II and Class III malocclusions. Standard sagittal split osteotomies carry risks of complications, including unfavorable osteotomy propagation (bad splits) toward the condyle, ramus fragmentation, lingual interference of the distal segment, and inferior alveolar nerve (IAN) injury. To minimize these risks, this study utilizes a modified medial cut positioned low (below the lingula in an area with adequate marrow space) and short (terminating anterior to the lingula). This design aims to prevent osteotomy extension into the condylar region and eliminate lingual interference during segment repositioning.

Conditions

Skeletal Class III Malocclusion; Skeletal Class II Malocclusion; Dentofacial Deformities

Keywords

Orthognathic Surgery; Sagittal Split Osteotomy; Skeletal Class II Malocclusion; Skeletal Class III Malocclusion

Outcome Measures

Primary Outcomes (1)

• Number of Participants with Unfavorable Osteotomy Split ("Bad Split")

  Intraoperative evaluation of the occurrence of unfavorable osteotomy propagation (e.g., condylar neck fracture, ramus fragmentation, or buccal/lingual plate fracture) during the sagittal split procedure, assessed via direct visualization and manual palpation.

  Intraoperative (during the surgical procedure)

Secondary Outcomes (10)

• Change from Baseline in Inferior Alveolar Nerve (IAN) Conduction Latency via TSSEP

  Baseline (preoperative), 1 month, 3 months, and 6 months postoperatively

• Number of Participants with IAN Entrapment in the Proximal Segment

  Intraoperative (during the surgical procedure)

• Incidence of Distal Segment Lingual Bony Interference

  Intraoperative (during the surgical procedure)

• Condylar Position within the Glenoid Fossa via Panoramic Radiography

  Postoperative Day 7 (within the first week postoperatively)

• Skeletal Stability and Surgical Movement Outcome

  3 months postoperatively

Study Arms (1)

Low Sagittal Medial Ramus Osteotomy Group

EXPERIMENTAL

Patients undergoing orthognathic surgery using the low sagittal medial ramus osteotomy modification. The medial osteotomy cut is initiated slightly above the mandibular occlusal plane, positioned low (below the lingula in an area with adequate marrow space) and short (terminating anterior to the lingula and retrolingual fossa) to achieve 3D mandibular repositioning guided by CAD/CAM virtual surgical planning.

Procedure: Low Sagittal Medial Ramus Osteotomy

Interventions

Low Sagittal Medial Ramus Osteotomy PROCEDURE

Patients undergoing orthognathic surgery using the low sagittal medial ramus osteotomy modification. The medial osteotomy cut is initiated slightly above the mandibular occlusal plane, positioned low (below the lingula in an area with adequate marrow space) and short (terminating anterior to the lingula and retrolingual fossa) to achieve 3D mandibular repositioning guided by CAD/CAM virtual surgical planning.

Low Sagittal Medial Ramus Osteotomy Group

Eligibility Criteria

• Age: 18 Years - 45 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64)

You may qualify if:

• Patients with skeletal Class II or Class III malocclusion requiring mandibular orthognathic surgery.
• Age range from 18 to 45 years old.
• Systematically healthy patients classified as ASA physical status I or II (American Society of Anesthesiologists)

You may not qualify if:

• Patients with a pre-existing history of inferior alveolar nerve (IAN) sensory impairment.
• Patients with active or severe degenerative joint disease (DJD).
• Patients with a prior history of orthognathic surgical procedures.
• Patients presenting with systemic diseases or conditions known to compromise normal bone healing.

Sponsors & Collaborators

• Al-Azhar University: lead

MeSH Terms

Conditions

Dentofacial Deformities

Condition Hierarchy (Ancestors)

Maxillofacial Abnormalities; Craniofacial Abnormalities; Musculoskeletal Abnormalities; Musculoskeletal Diseases; Stomatognathic System Abnormalities; Stomatognathic Diseases; Congenital Abnormalities; Congenital, Hereditary, and Neonatal Diseases and Abnormalities

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Assistant Lecturer, Oral and Maxillofacial Surgery Department, Faculty of Dental Medicine

Study Record Dates

• First Submitted: July 26, 2026
• First Posted: August 5, 2026
• Study Start (Estimated): September 1, 2026
• Primary Completion (Estimated): April 1, 2027
• Study Completion (Estimated): September 1, 2027
• Last Updated: August 5, 2026

Record last verified: 2026-07

Data Sharing

• IPD Sharing: Will share
• Shared Documents: STUDY PROTOCOL
• Time Frame: beginning after publication and for one year after
• Access Criteria: data will be provided upon reasonable request