W. Howard Davis

Long-term follow up of transoral rib grafts for mandibular atrophy

Nineteen patients who had autologous rib grafts for mandibular augmentation were monitored for six to 13 years to evaluate the rate of resorption as a function of time. Data were collected from panoramic radiographs that were corrected for distortion. The findings indicated that rapid resorption occurs during the first two years after grafting and decreases markedly thereafter. Although some prolonged benefits resulted from the procedure, it was concluded that it is not an ideal solution to the problem of ridge augmentation.

Long-term bony and soft tissue stability following advancement genioplasty

Twenty-three patients who had undergone advancement genioplasty were evaluated an average of over 3 years postsurgically for bone and soft tissue stability. Traced serial cephalometric radiographs revealed no discernible bony remodeling from gnathion to the menton region. Six cases showed minor posterior shifting of the inferior border segment. Although good correlation existed between hard and soft tissue movement, minor soft tissue variation occurred without obvious correlation to bony remodeling.

Improved maxillary stability with modified LeFort I technique

This modification of the LeFort I osteotomy places the horizontal bony cut higher and into the dense cortical bone of the maxillozygomatic complex. It gives greater stability and also provides a more solid bony base for intraosseous wiring of the mobilized segment. This usually eliminates the need for dento-osseous or maxillomandibular fixation, and the segments appear to solidify more quickly. Over the last year, we have used this technique in 23 cases (four maxillary advancements, seven one-piece maxillary intrusions, and 12 segmental maxillary intrusions) with very favorable results. This modification has given us greater control and stability, especially in combined maxillary and mandibular osteotomies.

Surgically uprighting and grafting mandibular second molars

A two-year follow-up was made of twenty-one impacted, mesially inclined mandibular molars which were surgically uprighted and splinted with autogenous bone grafts. There were two instances of follicular cysts in the adjacent impacted third molars and two instances of supereruption of uprighted teeth. With these exceptions, all uprightings were successful according to the criteria of continued root growth, normality of pulp chambers, normal periodontium, and normal contiguous structures.

Modified distolingual splitting technique for removal of impacted mandibular third molars: Technique

This first of two articles describes a modified distolingual splitting technique for removal of impaction of various classes. The second article evaluates the efficacy of the technique by reporting and comparing the incidence of postoperative sequelae with earlier research findings. In this technique, the lingual soft tissue is not separated from the bone. In addition, the fragmented lingual bone attached to the periosteum is not removed. The procedure is best performed with the patient under sedation or general anesthesia.

Resorption of the edentulous mandible after a vestibuloplasty with skin grafting

T, Id rote ures to improve the basal seat for an inadequately supported mandibular complete denture have been attempted from the time dentists began replacing natural dentition with artificial removable prostheses. As early as 1874 Thiersch’ described a technique of using epidermal grafting. This appears to have stimulated others to expand the technique and develop the skin grafting vestibuloplasty and lowering of the floor of the mouth (VSG and LFM) procedure.2-‘4 Research indicates that the VSG and LFM procedure is an effective treatment modality for patients who complain of an ill fitting denture, poor masticatory function, and pain. l5 The purpose of the VSG and LFM is to create a larger basal area of fixed epithelium for improved stability and support of the prosthesis. The procedure is an apparent improvement over other techniques because it offers several benefits, such as: (1) fixed tissue on which the denture rests allows stability during mastication and speech; (2) lengthening of the denture flanges, which provides a broader denture base to more widely distribute occlusal forces; (3) enhancing patient comfort, as the skin is a better stress-bearing tissue than mucosa; and (4) longevity of the result. Because VSG and LFM repositions muscle attachments, the question arises as to whether the mandibular resorption following this procedure is more rapid than in the untreated mandible. Hillerup,16 in a survey of 15 patients following a vestibular sulcus extension using the technique of Edlan and Mejchar,“~“’ reported that the procedure fails to protect alveolar bone and may even provoke accelerated bone resorption. However, the procedure of Edlan and Mejchar does not incorporate the use of a skin graft in conjunc-

Reconstruction of the severely resorbed mandible

Reconstruction of the severely resorbed mandible has long been a problem. Restoration of function and strength has been impaired by the lack of long-term retention of various bone grafting modalities. The use of hydroxyapatite as a scaffolding material to prolong the retention of grafted bone may hold promise of longer term strengthening by bone grafts. To allow the use of osseointegrated implants with this HA-bone grafting, porous HA (Interpore 200) was used in two patients. Although the 1- and 2-year follow-up of these patients is encouraging, further investigation is needed.

Reconstruction of alveolar width for orthodontic tooth movement: A case report

A problem that has limited orthodontic treatment is lack of buccal-lingual alveolar width into which teeth can be moved. Causes may range from surgical obliteration to physiologic constriction after tooth removal. Lack of buccal-lingual alveolar width does not have to be an orthodontic limitation anymore. A technique used routinely to graft alveolar clefts can remedy this problem. Autogenous cancellous bone is placed subperiosteally on the buccal aspect of the constricted edentulous space. The flap is closed over the bone. The adjacent teeth may be orthodontically moved into the grafted edentulous area in approximately 6 weeks. Long-term follow-up has revealed excellent orthodontic stability, periodontal health, and dental vitality. A case report of one patient with loss of buccal-lingual alveolar space is presented. It is concluded that loss or lack of sufficient buccal-lingual alveolar width no longer must be an orthodontic limiting factor.

Synovial chondromatosis of the temporomandibular joint

S ynovial chondromatosis is a rare, benign, usually monoarticular condition in which numerous cartilaginous bodies form by metaplasia of the sublining connective tissue of the synovial membrane.’ Although the etiology is uncertain, it is likely that the condition results when cells in the synovial lining undergo metaplastic change into chondroblasts that subsequently form cartilaginous bodies that may or may not calcify or ossify. As these bodies enlarge, they may become pedunculated and eventually break away, remaining trapped in and around the joint. Here, nourished by the synovial fluid, they remain viable and sometimes continue to increase in size. The clinical symptoms of synovial chondromatosis are similar to those of other internal derangements of the joints, including limited motion, swelling, and pain. The histological picture is, however, unique and includes evidence of cartilaginous metaplasia of the synovial connective tissue with nests of connective tissue cells undergoing transformation into cartilage. Only 26 patients with histologically confirmed synovial chondromatosis of the temporomandibular joint (TMJ) have been described in the English literature since the first case was reported in 1933.‘-” This report of this relatively rare condition serves to review the salient features of the condition.

Temporalis tendon release during mandibular sagittal ramus split osteotomy

Since the original description of the sagittal ramus six dissected specimens (Fig 2). The lingual nerve was also identified and found to be consistently inferior and medial to the temporalis tendon. The tendinous tissue was always easily distinguishable from nerve tissue. The lingual nerve location has been previously described as being on average 0.58 mm + 0.9 horizontally from the lingual plate and 2.28 mm f 1.96 on the average vertically below the alveolar crest (Fig 3).5 This location, verified in the cadaveric dissections, is clearly distinct from the location of the temporalis tendon. split osteotomy by Obwegeser,’ there have been a number of modifications to decrease relapse, reduce complications, and improve the ease with which the osteotomy is performed. Most modifications have dealt with changes in osteotomy design or soft tissue reflection.2.3 Our modification focuses on the insertion of the temporalis muscle and its influence on medial access, tissue reflection, and relapse. It involves elevation and transection of the tendonous insertion of the anterior temporalis muscle along the medial aspect of the mandibular body. Classically, the insertion of the temporalis muscle is described as being into the upper and anterior borders of the coronoid process, with the major portion on the medial side of the ramus and entire medial side of the coronoid. However, Hollinshead4 also found the anterior temporalis insertion to include the anterior part of the ramus, extend’hrg approximately to the third molar region.4 Clinically this is seen as a horizontal tendinous band that runs along the internal oblique ridge just superficial to the periosteum. It is found directly medial to the most common soft tissue incision used for the bilateral sagittal ramus split osteotomy, and is exposed and reflected each time the medial ramus is approached, often appearing as a tight band. After the sagittal ramus split osteotomy, the tendinous insertion remains attached to the distal or advancing segment of the mandible (Fig 1). This structure is easily indentified and has been verified on multiple cadaveric dissections. On exposure of the anterior insertion, the temporalis tendon was found to extend to the distal aspect of the second molar tooth in each of