Henk Tideman

Mandibular reconstruction in adults: a review

Mandibular defects may result from trauma, inflammatory disease and benign or malignant tumours. Mastication, speech and facial aesthetics are often severely compromised without reconstruction. The goal of mandibular reconstruction is to restore facial form and function, implying repair of mandibular continuity and muscle attachments. There should also be room for implant insertion so as to allow for rehabilitation of occlusion and articulation, whereas the function of the inferior alveolar nerve should be restored to assure adequate sensitivity of the lips. Mandibular reconstruction principles and techniques have evolved dramatically over the years. Refinements in techniques continue to improve patient quality of life. This paper reviews current techniques of mandibular reconstruction in adults and discusses the strengths and weaknesses of each.

Three-dimensional virtual-reality surgical planning and soft-tissue prediction for orthognathic surgery

Complex maxillofacial malformations continue to present challenges in analysis and correction beyond modern technology. The purpose of this paper is to present a virtual reality workbench for surgeons to perform virtual orthognathic surgical planning and soft-tissue prediction in three dimensions. A resulting surgical planning system, i.e., three-dimensional virtual reality surgical planning and soft-tissue prediction for orthognathic surgery, consists of four major stages: computed tomography (CT) data post-processing and reconstruction, three-dimensional (3-D) color facial soft-tissue model generation, virtual surgical planning and simulation, soft-tissue-change preoperative prediction. The surgical planning and simulation are based on a 3D CT reconstructed bone model, whereas the soft-tissue prediction is based on color texture-mapped and individualized facial soft-tissue model. Our approach is able to provide a quantitative osteotomy-simulated bone model and prediction of postoperative appearance with photorealistic quality. The prediction appearance can be visualized from any arbitrary viewing point using a low-cost personal computer-based system. This cost-effective solution can be easily adopted in any hospital for daily use.

Use of the buccal fat pad as a pedicled graft

The development, anatomy, and blood supply of the buccal fat pad are discussed, and the results in a series of patients treated with uncovered buccal fat pad grafts are presented.

The buccal fat pad in oral reconstruction

The use of the buccal fat pad (BFP) as an uncovered pedicled graft to close oral defects is relatively recent. A series of 29 consecutive cases of reconstruction utilizing the BFP is presented, showing excellent results and without added surgical morbidity. Indications include defects after benign or malignant tumour resection, and the combined BFP/temporalis myofascial pedicled flap is reported as an additional option in reconstruction. Histologic findings in healed reconstruction sites indicate fibrous replacement of the fat tissue, and epithelialization of its oral surface. From the results of this series, we conclude that the use of the BFP for the reconstruction of appropriate surgical defects in the mouth is worthy of consideration.

Blood loss and transfusion requirements in orthognathic surgery

Abstract Purpose: This study quantified the blood loss and transfusion requirements in orthognathic surgery. Patients and Methods: Three hundred sixty consecutive healthy orthognathic surgery patients were included in this retrospective study. The female:male ratio was 1.8:1, and the age range was 8 to 49 years (mean, 24). Estimated blood volume (EBV), estimated blood loss (EBL), and transfused blood were calculated. Results: EBL ranged from 50 to 5,000 mL (mean, 600) representing up to 73% of EBV (mean, 16%). In total, 24% (84 patients) were transfused, 8.7% (6 patients) after single-jaw surgery and iliac bone harvest and 26.7% (78 patients) after bimaxillary osteotomies. Forty-seven patients received 1 unit of transfused blood, 25 patients had 2 units, and 12 patients had more than 2 units. Most transfused patients lost 11% to 40% of EBV. Conclusions: Transfusion is not necessary for single-jaw surgery unless a bicoronal flap or iliac bone harvest are required. Although only 27% of bimaxillary osteotomy patients required transfusion of 1 to 2 units, this group was not predictable based on the type of procedure involved, and a further subgroup (4% of the 291 patients) required a larger transfusion.

The 3-dimensional stability of maxillary osteotomies in cleft palate patients with residual alveolar clefts

OBJECTIVES To evaluate the stability of maxillary osteotomies in cleft palate patients using miniplate fixation. DESIGN A prospective clinical study. SUBJECTS 46 consecutive cleft palate patients with residual alveolar clefts and maxillary hypoplasia in one or more dimensions. These patients underwent standardised maxillary osteotomies and simultaneous bone grafting of the alveolar cleft over 44 months during 1988-1992. Titanium mini-plate fixation was used for the maxilla in all patients. Follow-up ranged from 6 to 51 months with a mean of 28 months. MAIN OUTCOME MEASURES The 3-dimensional stability of maxillary osteotomies in cleft palate patients in the long term. RESULTS In the unilateral clefts, relapse in the horizontal plane was 22% and in the vertical plane 22.5%; in bilateral clefts, the relapse was 17.5% and 7% respectively, with no statistically significant difference between the two groups. Longitudinal analysis of the repositioned maxilla over a 3-year period showed that most of the relapse occurred in the first 6 months and stabilised at 2 years postoperatively. Relapse in the transverse plane, based on analysis of the study models of 26 cases, ranged from 13.4% to 33.6%. A clockwise rotational relapse of the maxilla was noted in bilateral cases. Postoperative orthodontics compensated for the horizontal relapse by increasing incisor proclination to maintain positive overjet. There was no significant difference between the relapse of bimaxillary cases and that of maxillary osteotomies alone. CONCLUSION The long-term 3-dimensional surgical stability, using miniplate fixation, has decreased the relapse of cleft maxillary osteotomies with simultaneous alveolar bone grafting to a level comparable to that of maxillary osteotomies in non-cleft patients.

Osteochondroma of the coronoid process of the mandible: Report of a case and review of the literature

A review of the literature and the addition of one case have revealed that, on the basis of strict histologic criteria, there are presently 30 published cases of osteochondroma of the coronoid process of the mandible. Twenty-one cases (70%) were men. Most osteochondromas developed before the age of 40 years. The lesions were mushroomlike in more than two thirds of the cases. Deformity of surrounding structures and facial deformity was found in most cases. The surgical approach was intraoral in the majority of cases. None of the reported cases showed a recurrence.

Interposed bone-graft augmentation of the atrophic mandible: (A progress report)

A follow-up study on 41 patients who had augmentation of the atrophic mandible by interposed bone graft is presented. Special emphasis has been put on the prosthetic implications. The rapid reduction in height measured postoperatively appeared almost to cease after 6 months. Some of the possible causes of this phenomenon are discussed.

A reappraisal of the interposed bone graft augmentation of the atrophic mandible

A follow-up on 148 patients who had undergone an interposed bonegraft augmentation of the atrophic mandible is presented. The first group consisted of 38 patients who underwent surgery 4-6 years ago. The second group of 70 patients has a follow-up period of 3 to 4 years. The third group of 40 patients was followed up from 2 to 3 years postoperatively. The phenomenon of post-operative bone resorption which continues for many years postoperatively, is discussed. The high incidence of nerve disturbances as found in this study is regarded as unacceptable. The dissection of the mandibular nerve out of its canal (decompression) in order to avoid nerve damage during the operation is not found to be of any advantage. A modified technique is recommended to circumvent this problem.

Immediate reconstruction following maxillectomy: A new method

A new method for immediate reconstruction of the maxilla after resection is described. The ipsilateral pedicled temporalis muscle is tunneled into the defect and sagittaly split into two layers. The inner layer is used to line the nasal side. An individually shaped titanium mesh, tightly filled with free autogenous corticocancellous bone, is fixed by titanium screws to the remnant of the zygoma and contralateral maxilla. The outer layer of the split muscle covers the reconstruction, the temporalis fascia forming the oral side. The method resulted in good cosmetic appearance and permitted the re-creation of a maxillary alveolar ridge suitable for endosseous implants or a simple prosthesis.