The goal of this study is to determine if the use of calcium phosphate paste in mandibular lengthening surgery causes more complications as surgical site infections and hardware removal.

An evaluation will be made to determine if the benefits of the use of the paste (3D-stability, prevention of early relapse and unaesthetic indentation) outweighs the disadvantages.

The sagittal split osteotomy (SSO) is commonly used to correct dentofacial discrepancies. Correction of distocclusion can be achieved through lengthening of the mandible, and a balanced facial appearance can be obtained by increasing chin projection.

Calcium phosphate paste is used in mandibular lengthening surgery to avoid an unaesthetic notching at the lower border(1)(2) and to help stabilize the segments when osteosynthesis slippage is feared for. A recently performed retrospective study showed an increase of infectious complications when calcium phosphate paste was used for this indications. Several precautions were identified that could be undertaken to decrease the infectious complications. The study concluded that a prospective study was required in which these precautions were implemented to determine whether infectious complications can be reduced.

The aim of this study is to investigate whether the hardened paste still increases the incidence of site infections after implementation of several precautions and the use of a standardized antibiotic prophylactic protocol.

Inclusion Criteria:

• All patients with dysgnatic deformities requiring mandibular lengthening surgery
• Gender: M/F
• Age: >15y-75y

Exclusion Criteria:

• Previous orthognathic surgery
• Congenital facial malformations
• Unilateral SSO
• Immunodeficiency
• Simultaneous removal of lower third molars
• Incomplete postoperative follow-up

Patients undergoing bilateral sagittal split osteotomy