Nabil Samman

Computer‐assisted three‐dimensional surgical planning and simulation: 3D virtual osteotomy

A computer-assisted three-dimensional virtual osteotomy system for orthognathic surgery (CAVOS) is presented. The virtual reality workbench is used for surgical planning. The surgeon immerses in a virtual reality environment with stereo eyewear, holds a virtual scalpel (3D Mouse) and operates on a real patient (3D visualization) to obtain pre-surgical prediction (3D bony segment movements). Virtual surgery on a computer-generated 3D head model is simulated and can be visualized from any arbitrary viewing point in a personal computer system.

Impact of orthognathic surgery on quality of life.

PURPOSEnTo determine changes in quality of life (QOL) following orthognathic surgery in patients with dentofacial deformity, using generic health, generic oral health, and condition-specific QOL approaches.nnnMATERIALS AND METHODSnThirty-six patients were evaluated at baseline presurgical (T(0)), 6 weeks postoperatively (T(1)), and 6 months postoperatively (T(2)). Generic health-related QOL was assessed using the 36-item Short Form Health Survey (SF-36), generic oral health-related QOL was assessed by the 14-item Short Form Oral Health Impact Profile (OHIP-14), and condition-specific QOL was assessed by the 22-item Orthognathic Quality of Life Questionnaire (OQLQ).nnnRESULTSnThere was a significant reduction (deterioration) in SF-36 summary physical (P < .01) and mental health scores (P < .001) at 6 weeks after surgery but no significant change in overall OHIP-14 or OQLQ scores. At 6 months after surgery, SF-36 summary scores returned to baseline levels and significant reduction (improvements) in OHIP-14 (P < .001) and OQLQ mean scores (P < .001) were observed.nnnCONCLUSIONSnSignificant changes in QOL occurred following orthognathic surgery. A marked but transient deterioration in many aspects related to general well being was noted in the early postoperative period and significant improvement was documented by 6 months. A comprehensive assessment of QOL using generic health, generic oral health, and condition-specific approaches proved useful in determining such changes.

Computer-assisted three-dimensional surgical planning and simulation: 3D color facial model generation

A scheme for texture mapping a 3D individualized color photo-realistic facial model from real color portraits and CT data is described. First, 3D CT images including both soft and hard tissues should be reconstructed from sequential CT slices, using a surface rendering technique. Facial features are extracted from 3D soft tissue. A generic mesh is individualized by correspondence matching and interpolation from those feature vertices. Three digitized color portraits with the third dimension from reconstructed soft tissue are blended and texture-mapped onto the 3D head model (mesh). A color simulated human head generated from frontal, right and left real color portraits can be viewed from an arbitrary angle in an inexpensive and user-friendly conventional personal computer. This scheme is the basic procedure in 3D computer-assisted simulation surgery.

Feasibility of osteotomies in fibrous dysplasia of the jaws

Two examples are presented of osteotomies performed simultaneously with surgical recontouring in cases of fibrous dysplasia of the jaws. Osteotomies are necessary when a coexistent discrepancy in jaw relationship is present. This provides a functional as well as aesthetic result. Rigid miniplate fixation was utilised, and dysplastic bone healing was uneventful, and found clinically not to differ from that of normal bone. Osteotomy is thus feasible in dysplastic bone, and may complement recontouring in achieving a better result.