Search PubMed⌕ Search

Biomedical subjects

H Tideman

Publications and source records attributed to H Tideman.

At least 55 records · Page 3Linked to original sources

The use of mouldable acrylic for restoration of the temporalis flap donor site.

Despite the wide popularity of the pedicled temporalis myofascial flap, aesthetic management of the temporalis donor site has received little attention. A technique for immediate camouflage of the temporalis flap donor site with cold-cure methyl methacrylate, either alone or in combination with residual muscle in the temporal fossa, is presented. A retrospective evaluation of this technique in 34 consecutive patients was undertaken, with particular reference to the aesthetic results and morbidity associated with the use of cold-cure acrylic for this form of reconstruction. Apart from transient postoperative swelling and neuropraxia, no major or lasting complications associated with the use of cold-cure acrylic were recorded. The aesthetics of the camouflaged temporalis donor site by acrylic alone, or when combined with part of the temporalis muscle, was judged objectively to be excellent in 25 patients, satisfactory in 3 patients, and poor in 2 patients. 4 patients who did not have acrylic reconstruction, but had part of the temporalis muscle transposed to conceal the anterior fossa depression, leaving the posterior fossa unreconstructed, were judged mostly as satisfactory. Histology of the soft tissues around an acrylic implant after nearly 2 years confirmed the good biocompatibility of this material. It is concluded that this technique is a safe and reliable method for immediate camouflaging of the temporal fossa after harvesting a temporalis muscle flap.

Adolescent↗

Soft tissue changes following maxillary osteotomies in cleft lip and palate and non-cleft patients.

A retrospective study of 25 patients with unilateral cleft lip and palate and 25 patients with hypoplastic maxillae without a cleft was carried out to evaluate the effects of maxillary osteotomies at the Le Fort I level on the lip and nose profile. The pre-surgical cephalometric tracing was superimposed twice on the post-surgical cephalogram, on the cranial structures and the anterior maxillary structures, for landmark movement measurement. Results showed statistically significant correlations between soft and hard tissue movement in the cleft group. On average, the ratios of horizontal nasal tip, nasal base and lip movement to underlying hard tissue movement were approximately one fourth, one half and two thirds respectively. The ratio of vertical lip to incisor movement was about one half. The correlations were less significant in the non-cleft group, only the upper lip movement showed statistically significant correlation with hard tissue movement, with a ratio of one half horizontally and one third vertically. It was concluded that in maxillary osteotomy, the cleft group showed a higher soft tissue to hard tissue movement ratio. The correlation between soft and hard tissue movements were more statistically significant in the cleft group than in the non-cleft group. However, though statistically significant, the level of correlation was not strong on an individual basis except in the horizontal lip response of the cleft group. Individual variation was wide and clinical judgement needs to be considered accordingly.

Adult↗

Chondrosarcoma of the mandible presenting as periodontal lesions: report of 2 cases.

A review of the literature and the addition of 2 cases in the mandibular symphyseal region serve to illustrate the protean presentation of chondrosarcomas. These 2 cases presented as periodontal lesions with associated bone loss. A high index of suspicion is required to make an early diagnosis. The importance of submitting biopsy specimens for histology is stressed, and it is recommended that definitive treatment be carried out as rapidly as possible after diagnosis is known. The surgical procedures undertaken were conservative, and patients have remained disease-free after 3.5 years and 3 years respectively. For small lesions, early segmental resection is not necessary in this region. Only recurrence should be treated by symphyseal resection with its increased morbidity. Close follow-up is mandatory.

Adult↗

The stability of the downgrafted maxilla in the cleft lip and palate patient.

Vertical stability following maxillary downgrafting in cleft patients is poor with an average relapse of 42 per cent (ranged 0-100 per cent). Overcompensation should, therefore, be undertaken with 2 mm added to the downgraft movement for bony relapse and 1 mm added to the downgraft movement for upper lip lengthening. The Tideman et al. method for advancement of the lesser maxillary segment is a very stable procedure (less than 8 per cent relapse). Semi-rigid fixation with plates, bone grafting and 'ramping' enhances stability; and freeway space assessment preoperatively is an important guide to relapse potential in the downgrafted cleft maxilla. All surgical prediction tracings should be done with the patient at the occlusal vertical dimension to prevent inadequate maxillary advancement and subsequent reverse overjet or excessive anterior incisor proclination developing with vertical relapse.

Bone Plates↗

Reconstructive options for maxillary defects.

Reconstruction of the maxilla should aim to restore appearance, speech and occlusion. With modern reconstructive techniques and availability of an increasing variety of reliable tissue flaps, many of the traditional problems of treatment have been overcome. This paper reviews local and distant tissue flaps useful in rehabilitating an acquired maxillary defect of various dimensions. The local flaps discussed include flaps from the palate, cheek, tongue and the buccal fat pad. The distant flaps considered are the temporalis myofascial flap, pedicled cutaneous and myocutaneous flaps, and vascularized free flaps. Bony reconstruction of the maxilla with particular emphasis on restoring an anatomical alveolar ridge for occlusal rehabilitation by dental implants is presented.

Bone Transplantation↗

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.

Humans↗

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.

Adipose Tissue↗

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.

Adolescent↗

Bilateral transverse facial clefts and accessory maxillae--variant or separate entity?

We report an extremely rare case of bilateral transverse facial clefts and accessory maxillae with severe mandibular hypoplasia in a 7-year-old Chinese boy. The transverse facial clefts had been repaired in infancy. The accessory maxillae were excised via a combined temporal and oral approach. Functional orthodontic appliance therapy was not feasible due to restricted protrusive movements of the mandible. Bimaxillary osteotomies were performed one year later due to failure mandibular catch-up growth to occur. The pathogenesis of the accessory maxillae in the presence of lateral facial clefting is postulated to be compensatory mesenchymal growth from the temporal region, and a case is made for this condition to be considered as a possible syndrome rather than a variant of the transverse facial cleft.

Child↗

Periosteal Gaucher-like cells in beta-thalassemia major.

A 24-year-old Chinese woman who has undergone staged surgery for craniofacial deformity secondary to beta-thalassemia major is presented. Local clusters of Gaucher-like cells were found in the periosteum of the mandible. The histologic and ultrastructural features of these cells are described and the pathogenesis and differential diagnoses discussed. To the best of our knowledge, this is the first reported case of Gaucher-like cells occurring outside the lymphohematopoietic system in thalassemic patients.

Adult↗

Analysis of 300 dentofacial deformities in Hong Kong.

The records of 300 consecutive Chinese patients with a dentofacial deformity were reviewed to determine the spectrum and characteristics of deformities presenting to a university joint orthognathic clinic. Twenty-six percent of the patients had cleft lip and palate with maxillary hypoplasia; within this group, 26% had double jaw deformity and 5% had nasomaxillary hypoplasia. Of the noncleft group, 47% were Class III facial types, of which 59% were due to mandibular hyperplasia. Of the noncleft group, facial asymmetry accounted for 21%, long face for 18%, bimaxillary protrusion for 14%, Class II types for 11%, and short face for 4%. Overall, there was a high incidence of two-jaw deformity, suggesting that severity may be a major factor in the decision by patients to seek treatment. Findings from this study are thought to be generally applicable to overseas Chinese.

Adolescent↗

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.

Adult↗

Multicenter follow-up study of the transmandibular implant.

The purpose of this multicenter study was to review the results of treatment and identify complications in edentulous patients who were treated with the transmandibular implant. A total of 190 patients were treated in four university departments. These patients presented for treatment with mandibular bone heights that ranged from 4 to 18 mm (mean, 10 mm). After postoperative periods that ranged from 3 months to 5 years, 182 of the 190 implants (95.8%) were stable and functional. Three implants were removed due to perioperative fractures in mandibles with 4 to 6 mm of bone height. Five were removed due to infection which occurred within the first 3 months after surgery. Reversible complications that developed in 22.2% of the patients were treated successfully. The 182 implants in function demonstrated no mobility and no infrabony pockets around any of the transmucosal posts. The results of this study demonstrate that the transmandibular implant has acceptable predictability and reliability for reconstruction of patients with severe atrophy of the mandibular alveolar process.

Bone Resorption↗

Biological and clinical evaluation of the transmandibular implant.

The transmandibular implant has been shown to be a successful clinical solution to prosthetic rehabilitation of patients with gross mandibular atrophy. Aspects of the biocompatibility of the implant material including the component metals in the alloy have been tested in an animal model utilizing sheep. The initial Adelaide results in the clinical multicentre trial are presented. These were generally excellent and the reasons for the few failures are presented.

Aged↗

The accuracy of temporomandibular joint arthroscopy.

The results of preoperative investigation arthroscopy and surgical exploration were compared for 12 T.M. joints in 9 female patients. Arthroscopy was found to contribute to the diagnosis and correlate accurately to the other investigations. The degree of iatrogenic damage was low.

Adolescent↗