K. Ai-Ruhaimi, BDS, MSc, Dr Med Dent;*
A.L. Nwoku, MD, DMD, FWACS, FMCDS, F1CS*
H.S. Shaikh, LDSCPS, BDS, MDS**
*Department of Biomedical Dental Sciences,
**Department of Preventive Dental Sciences,
King Saud University, College of Dentistry, P.O. Box 60169, Riyadh 11545, Saudi Arabia.

Almost all conferences for plastic and maxillofacial surgery discuss reports on several methods of orthognathic surgery, planning, success results, and complications of the different proce­ dures carried out to correct patient's soft and hard tissues frontal profiles and occlusal dis­ crepancies. Various principles are involved in the diagnosis and treatment of facial deformities. However, the most important consideration, after all, is the final accepted aesthetic and func­ tional requirements and stability of the moved segments.
The objective of this paper is to give the basic principles of treatment planning for correcting facial discrepancies, surgical approach to different cases, and the methods to increase stability of the moved segments. Six cases are included to illustrate the different aspects of treatment planning, surgical management, and stabilization methods.

The mandible and maxilla constitute a major portion of the facial skeleton. Small alterations (congenital and developmental) in the intimate relation­ ship of these facial bones to the rest of the facial skeleton can produce many malformations. In cor­ recting these anomalies, the goal on the one hand is the restoration of normal occlusion and normal function, and on the other hand the establishment of an aesthetically pleasing facial appearance that satisfies the patient.
Orthognathic treatment and planning representsan attempt to return hard (skeletal and dental) and soft tissues from abnormal to normal relationship. In order to make a diagnosis, a thorough patient examination is essential. This should be followed by evaluating the records obtained, which include photographs and radiographs as well as models and cephalometric analysis, in order to predict an acceptable profile for the patient. Performing the planned surgical procedure on dental models for the patient allows prediction on the amount of sur­ gical movement of the segment, occlusal relation­ ship, and indicates the need of pre-surgical orthodontic movement of the teeth. The proposed end-result of the treatment might need pre-and/or post-surgical dental correction to align the axis of the teeth with the axis of their alveolar processes.
Prime indications for pre-surgical orthodontic treatment include alignment of teeth that will impair movement of the segment, and creation of space between teeth for the osteotomy line espe­ cially in cases of segmental osteotomy.
Various principles are involved in the diagnosis and treatment of facial deformities. The most important consideration after all, however, is the final acceptability to the patient of the aesthetic and functional requirements of the proposed repair. The surgeon's treatment-planning is greatly influenced by imaginative and intuitive factors. With this in mind, and considering that an accurate plan­ ning and prediction of the final result form the basis for a successful outcome of orthognalhic surgery, we publish this paper and illustrate the diversity in planning with six interesting and, at the same time, challenging cases.

Case 1
A 19-year-old female patient presented with prognathism, a reverse overjet of 7 mm, and soft tissue deficiency in the cheek and infra-orbital areas [Figs. 1a-d]. Evaluation of clinical data, cephalometric tracing pre-operatively and the pre­ diction-tracing-operative graphs together with the superimposition of the surgical template on the original problem and clinical photographs assisted in the selection of the choice of treatment.
The surgical models suggested two alternative methods of treatment. Firstly, the mandible could be moved posteriorly to reduce prognathism and correct occlusal relationship. Secondly, the maxilla could be advanced forward to improve the soft tis­ sue deficiency of the cheek and infra-orbital areas. The choice followed was a posterior setback of the mandible using the sagittal splitting technique of the ascending ramus and bone graft onlay in both areas of canine fossae to improve cheek promi­ nence. The split segments of the mandible were secured with circumandibular wiring and proper occlusion was established with intermaxillary fixa­ tion for four weeks. Corrugated drains were inserted through the incision lines intraorally and facial pressure dressing were applied for two days. Healing was uneventful and post-operative result was satisfactory [Figs. 1d-gJ.
Case 2
A 20-year-old male patient presented with open-bite from the first molar on one side to the first molar on the other side [Figs. 2a-c|. The height of the lip line was acceptable. Evaluation of the parameters for prediction of the final result was done as in Case 1. The study showed that a sagittal splitting osteotomy to rotate the mandible upwards in order to close the open bite, putting the teeth in occlusion and  reducing the height of the lower third was the best choice. The split segments of the mandible were secured with intraosseous wiring and intermaxillary fixation was left for six weeks to ensure stability of the split segments. Drains and facial bandages were utilized the same way as in the previous case. The final result is shown in Figures 2d-g,
Case 3
A female patient, 19 years of age, complained of pain in both temporomandibular joints. The radiologic examination showed hypoplasia of the right side of the mandible of unknown aetiology [Fig. 3a].
The clinical evaluation showed a slight deviation of the chin to the left side due to a compensatory attempt of the right side of the mandible to over­ come the deficiency of the underdeveloped left side. There was also a crossbite [Figs. 3b-c].
Skeletal bases were within normal ranges and the horizontai occlusal plane of the posterior teeth was parallel to the plane of the eyes. Occlusal relation­ ships of the upper and lower posterior teeth [Fig. 3c] were within the acceptable limits.
The cuspal edge to edge occlusion of some of these teeth could be aligned orthodontically but the distorted occlusion of the lower anterior teeth were amenable only to surgical correction by anterior mandibular subapical segmental osteotomy from first bicuspid on one side to first bicuspid on the other side, and raising the segment by 3 mm.
Surgical models showed that the occlusion could be restored especially posteriorly if sagittal splitting osteotomy was performed. Instead of performing genioplasty to correct the position of the chin, a part of the lower border of the chin on the right side was cut and used to fill the space created after the anterior segment was lifted. The lower border of the chin was smoothened with a large round bur giving a fairly good contour to the chin [Figs. 3d-e].
Case 4
A 20-year-old male patient presented with an openbite caused by bimaxillary discrepancies [Figs. 4a-c]. The upper lip line was low covering the upper teeth when the patient smiled, and there was reverse overjet of 5 mm. The size and position of the skeletal bases, however, were within normal range apart from the anterior segments (premolar to pre­ molar). Accordingly, a decision was made to move the upper and lower anterior segments only after extracting all first bicuspids. Movement of the upper segment from first bicuspid to the contra-lateral first bicuspid was done anteriorly to improve upper lip profile, and inferiorly to raise the lip line to enable the anterior teeth to show when the patient talks or smiles, and the segment was moved to the left side to put the left central tooth in the midline. After orthodontic alignment was completed, a crown would replace the other missing central incisor. The lower segment was moved posteriorly to reduce the reverse overjet and improve the position of the lower lip, and was tilted to achieve the normal angle with the lower skeletal base [Figs. 4d-h].
Case 5
A 23-year-old man presented with openbite and deficiency of the chin [Figs. 5a-c]. Clinical model, photographic and cephalometric analyses suggested correcting the openbite and facial height by performing a lower anterior segmental osteotomy from the first bicuspid on one side to the first bicuspid on the other side. The height of the chin was reduced by 5 mm in a sandwich-osteotomy, and then the piece of bone removed was used to graft the space created after the anterior segment was raised. The position of the chin was corrected with a genioplasty. The post­ operative result is shown in Figures 5d-f.
Case 6
An 18-year-old man had bilateral fractures of the mandible. The fractured segments were reduced and fixed in their pre-accident position, but the teeth had been in a reverse overjet relationship. The patient was rescheduled again after healing of the fractures for orthognathic surgery [Figs. 6a-c]. A look at his pre-operative profile [Fig. 6b] revealed a retroposition of the maxilla and depression of the infra-orbital area, giving an appearance of pseudo-prognathism. Shifting of the midline is a common finding in ectopic eruption of canines, and the shifting is usually towards the affected side.
Following our usual pre-operative planning pro­ cedures, plans were made to correct the maxilla and not the mandible, using a Le Fort I osteotomy to advance the maxilla, and to fill the lateral bone gaps with bone graft. Advancement of the maxilla was expected to correct the dental discrepancy and improve the prominence of the cheek. According to the study of surgical models in this case, a shifted midline would be more stable if cor­ rected orthodonlically after surgery. Blood transfu­ sion was found necessary in this type of surgery, as the patient was normally expected to lose between 600 and 1100 cc of blood during surgery. A piece of bone taken from the iliac crest was inserted in the space created in the pterygo-maxillary area on each side, behind the maxillary tuberosity, and intermaxillary fixation remained in place for five weeks. Figures 6a-f show the condition before and after surgical correction.

Case 1
A 19-year-old female patient presented with prognathism, a reverse overjet of 7 mm, and soft tissue deficiency in the cheek and infra-orbital areas [Figs. 1a-d]. Evaluation of clinical data, cephalometric tracing pre-operatively and the pre­ diction-tracing-operative graphs together with the superimposition of the surgical template on the original problem and clinical photographs assisted in the selection of the choice of treatment.
The surgical models suggested two alternative methods of treatment. Firstly, the mandible could be moved posteriorly to reduce prognathism and correct occlusal relationship. Secondly, the maxilla could be advanced forward to improve the soft tis­ sue deficiency of the cheek and infra-orbital areas. The choice followed was a posterior setback of the mandible using the sagittal splitting technique of the ascending ramus and bone graft onlay in both areas of canine fossae to improve cheek promi­ nence. The split segments of the mandible were secured with circumandibular wiring and proper occlusion was established with intermaxillary fixa­ tion for four weeks. Corrugated drains were inserted through the incision lines intraorally and facial pressure dressing were applied for two days. Healing was uneventful and post-operative result was satisfactory [Figs. 1d-gJ.
Case 2
A 20-year-old male patient presented with open-bite from the first molar on one side to the first molar on the other side [Figs. 2a-c|. The height of the lip line was acceptable. Evaluation of the parameters for prediction of the final result was done as in Case 1. The study showed that a sagittal splitting osteotomy to rotate the mandible upwards in order to close the open bite, putting the teeth in occlusion and  reducing the height of the lower third was the best choice. The split segments of the mandible were secured with intraosseous wiring and intermaxillary fixation was left for six weeks to ensure stability of the split segments. Drains and facial bandages were utilized the same way as in the previous case. The final result is shown in Figures 2d-g,
Case 3
A female patient, 19 years of age, complained of pain in both temporomandibular joints. The radiologic examination showed hypoplasia of the right side of the mandible of unknown aetiology [Fig. 3a].
The clinical evaluation showed a slight deviation of the chin to the left side due to a compensatory attempt of the right side of the mandible to over­ come the deficiency of the underdeveloped left side. There was also a crossbite [Figs. 3b-c].
Skeletal bases were within normal ranges and the horizontai occlusal plane of the posterior teeth was parallel to the plane of the eyes. Occlusal relation­ ships of the upper and lower posterior teeth [Fig. 3c] were within the acceptable limits.
The cuspal edge to edge occlusion of some of these teeth could be aligned orthodontically but the distorted occlusion of the lower anterior teeth were amenable only to surgical correction by anterior mandibular subapical segmental osteotomy from first bicuspid on one side to first bicuspid on the other side, and raising the segment by 3 mm.
Surgical models showed that the occlusion could be restored especially posteriorly if sagittal splitting osteotomy was performed. Instead of performing genioplasty to correct the position of the chin, a part of the lower border of the chin on the right side was cut and used to fill the space created after the anterior segment was lifted. The lower border of the chin was smoothened with a large round bur giving a fairly good contour to the chin [Figs. 3d-e].
Case 4
A 20-year-old male patient presented with an openbite caused by bimaxillary discrepancies [Figs. 4a-c]. The upper lip line was low covering the upper teeth when the patient smiled, and there was reverse overjet of 5 mm. The size and position of the skeletal bases, however, were within normal range apart from the anterior segments (premolar to pre­ molar). Accordingly, a decision was made to move the upper and lower anterior segments only after extracting all first bicuspids. Movement of the upper segment from first bicuspid to the contra-lateral first bicuspid was done anteriorly to improve upper lip profile, and inferiorly to raise the lip line to enable the anterior teeth to show when the patient talks or smiles, and the segment was moved to the left side to put the left central tooth in the midline. After orthodontic alignment was completed, a crown would replace the other missing central incisor. The lower segment was moved posteriorly to reduce the reverse overjet and improve the position of the lower lip, and was tilted to achieve the normal angle with the lower skeletal base [Figs. 4d-h].
Case 5
A 23-year-old man presented with openbite and deficiency of the chin [Figs. 5a-c]. Clinical model, photographic and cephalometric analyses suggested correcting the openbite and facial height by performing a lower anterior segmental osteotomy from the first bicuspid on one side to the first bicuspid on the other side. The height of the chin was reduced by 5 mm in a sandwich-osteotomy, and then the piece of bone removed was used to graft the space created after the anterior segment was raised. The position of the chin was corrected with a genioplasty. The post­ operative result is shown in Figures 5d-f.
Case 6
An 18-year-old man had bilateral fractures of the mandible. The fractured segments were reduced and fixed in their pre-accident position, but the teeth had been in a reverse overjet relationship. The patient was rescheduled again after healing of the fractures for orthognathic surgery [Figs. 6a-c]. A look at his pre-operative profile [Fig. 6b] revealed a retroposition of the maxilla and depression of the infra-orbital area, giving an appearance of pseudo-prognathism. Shifting of the midline is a common finding in ectopic eruption of canines, and the shifting is usually towards the affected side.
Following our usual pre-operative planning pro­ cedures, plans were made to correct the maxilla and not the mandible, using a Le Fort I osteotomy to advance the maxilla, and to fill the lateral bone gaps with bone graft. Advancement of the maxilla was expected to correct the dental discrepancy and improve the prominence of the cheek. According to the study of surgical models in this case, a shifted midline would be more stable if cor­ rected orthodonlically after surgery. Blood transfu­ sion was found necessary in this type of surgery, as the patient was normally expected to lose between 600 and 1100 cc of blood during surgery. A piece of bone taken from the iliac crest was inserted in the space created in the pterygo-maxillary area on each side, behind the maxillary tuberosity, and intermaxillary fixation remained in place for five weeks. Figures 6a-f show the condition before and after surgical correction.