Gerard Kearns

Placement of endosseous implants in children and adolescents with hereditary ectodermal dysplasia

OBJECTIVE The purposes of this investigation were to study the feasibility of placing endosseous implants in children and adolescents with ectodermal dysplasia and to assess the position and stability of such implants during growth. This article reports on 6 subjects with long-term follow-up. Study design. A prospective study was commenced in 1991. Patients with hereditary ectodermal dysplasia who were over the age of 5 years and who presented to the University of California San Francisco Ectodermal Dysplasia Clinic for dental treatment were included and maintained in the study. In each case, clinical and radiographic records were obtained before treatment, immediately after implant placement, at delivery of the prosthesis, and subsequently at yearly intervals. Six subjects are reported, 4 as members of the prospective study group and 2 who had been treated before the study began. RESULTS A total of 41 implants (19 maxillary, 22 mandibular) were placed. The average follow-up after implant placement was 7.8 years (range, 6-11 years), and the average time since restoration was 6 years (range, 5-10 years). Forty implants successfully integrated and have been restored. There was no evidence that implant placement or prosthetic rehabilitation resulted in restriction of transverse or sagittal growth. One mandibular implant, placed in a partially dentate 5-year-old, became submerged because of adjacent alveolar development and required placement of a longer abutment. Four maxillary implants placed in a partially dentate 7-year-old also became submerged and required prosthetic revision and the placement of longer abutments. CONCLUSIONS This preliminary report suggests that endosseous implants can be successfully placed and can provide support for prosthetic restoration in patients with hereditary ectodermal dysplasia. However, vertical dentoalveolar growth results in submergence of the implant relative to the adjacent natural dentition when implants are placed adjacent to erupting permanent teeth.

Placement of endosseous implants in grafted alveolar clefts.

OBJECTIVE The purpose of this study was to determine the optimal timing for placement and to evaluate short- and long-term outcomes of endosseous implants in bone-grafted alveolar clefts. DESIGN Fourteen patients who underwent alveolar cleft bone grafting (ACBG) and closure of an oronasal fistula followed by restoration of the missing lateral incisor tooth using endosseous implants (EI) were studied. The oronasal fistulae were closed using local flaps, and the alveolus was grafted with fresh autogenous iliac marrow. Endosseous implants were placed a minimum of 4 months following ACBG. The average age at ACBG was 20.35 years (range, 12-65 yr), and at implant placement 22.2 years (range, 15-66 yr). It was necessary to regraft the alveolar cleft region in six patients to provide adequate bone volume for implant placement. Those who required alveolar regrafting had an increased mean interval between the initial ACBG and planned implant placement compared to the patients with adequate bone available for implant placement 26.4 months (range, 4-46 mo) versus 15.75 months (range, 4-36 mo). RESULTS Twenty-nine implants were placed in 14 patients, 9 outside of the cleft region and 20 in grafted alveolar clefts. Eighteen of 20 (90%) implants in the bone-grafted alveolar clefts have been successfully restored. The mean follow-up after implant placement was 39.1 months (range, 1-54 mo), and after restoration 28.5 months (range, 1-47 mo). CONCLUSIONS Endosseous implants can be placed in bone-grafted alveolar clefts. Consideration should be given to the adequacy of graft volume and ridge morphology at the time of ACBG. The interval between ACBG and implant placement is important. The greater the interval beyond 4 months, the more likely there will be inadequate bone volume to accept an implant.

The removal of plates and screws after Le Fort I osteotomy

PURPOSE This study is a retrospective chart review designed to evaluate the incidence and reasons for removal of plates and screws after Le Fort I osteotomy. PATIENTS AND METHODS The study sample consisted of patients who underwent Le Fort I osteotomy at the University of California, San Francisco, and Northwestern University in Chicago between December 1985 and December 1994. All patients in the study were treated with internal fixation using 2.0-mm plates and screws. All data were obtained from medical records and operative reports. The following intraoperative variables were evaluated: hardware material, plate size and shape, plate location, screw size, graft material, and intraoperative complications. For patients requiring removal of hardware, the number, location and type of plates and screws removed were recorded, as well as the reasons for removal. RESULTS A total of 738 plates were placed in 190 patients. Twenty-one of the 190 patients (11.1%) had at least a portion of the hardware removed because they either requested removal or required removal secondary to complications related to the plate or screw. This represented 70 of 738 plates (9.5%). The percentage of titanium plates removed was greater than the percentage of Vitallium plates removed. The reasons for removal included pain, palpation by the patient, sinusitis, temperature sensitivity, infection, and patient request. CONCLUSION Only a small number of patients (10.6%) develop complications from plates or screws that required their removal. In each case, prompt removal constituted adequate management.

Progression of facial asymmetry in hemifacial microsomia.

Hemifacial microsomia is a common craniofacial anomaly, variably affecting structures derived from the first and second pharyngeal arches. Correction of the skeletal deformity in children has been advocated to improve growth potential and reduce secondary deformity. However, contrary reports have suggested that facial asymmetry in hemifacial microsomia does not increase with growth; therefore, skeletal correction can be postponed, even until adolescence. The purpose of this study was to test the hypothesis that facial asymmetry in hemifacial microsomia is progressive. This is a retrospective evaluation of 67 patients with untreated hemifacial microsomia. The patients were categorized as: group I (mandible type I, IIa), n = 38, and group II (mandible type IIb, III), n = 29. Pretreatment posterior-anterior cephalometric radiographs were used to analyze asymmetry by measuring the angle between the true horizontal and the following planes: piriform rim, maxillary occlusal plane, and intergonial angle. Angular measurements were averaged for patients in the deciduous (<6 years), mixed (≥6<13 years), and permanent dentition (≥13 years). In group I, angle piriform rim, maxillary occlusal plane, and intergonial angle increased from 7.0, 4.3, and 4.4 to 8.4, 6.6, and 6.1 degrees, respectively [mean age, 4.1 (deciduous) to 8.6 (mixed) to 21.0 (permanent) years]. In group II, angle piriform rim, maxillary occlusal plane, and intergonial angle increased from 9.5, 6.2, and 5.3 to 11.7, 7.6, and 8.0 degrees, respectively [mean age, 3.4 (deciduous) to 8.0 (mixed) years]. These data demonstrate that hemifacial microsomia is progressive and underscores the importance of early surgical correction of mandibular asymmetry in this disorder. (Plast. Reconstr. Surg. 105: 492, 2000.)

Placement of an endosseous implant in a growing child with ectodermal dysplasia

This article reports placement of a single mandibular endosseous implant in a 5-year-old patient with hypohidrotic ectodermal dysplasia and oligodontia. This congenital anomaly does not appear to retard healing and the osseointegration remains after 5 1/2 years of loading. Surgical, prosthodontic, and growth and development considerations are presented.

The distribution of the auriculotemporal nerve around the temporomandibular joint

OBJECTIVE The purpose of this cadaver dissection was to study the position of the auriculotemporal nerve in relation to the mandibular condyle, capsular tissues, articular fossa, and lateral pterygoid muscle and to evaluate the anatomic possibility of nerve impingement or irritation by the surrounding structures. STUDY DESIGN Eight cadaveric heads (16 sides) were dissected. The auriculotemporal nerve was identified by following its course around the middle meningeal artery. The course of the nerve trunk was dissected from the middle meningeal artery to the terminal branches within the temporomandibular disk. The horizontal distance between the auriculotemporal nerve and the medial portion of the condyle/condylar neck was measured. The vertical distance from the most superior portion of the articular condyle to the superior border of the auriculotemporal nerve was measured. RESULTS The auriculotemporal nerve was identified on each side, and a single trunk was evident along the medial aspect of the condylar neck. At the posterior border of the lateral pterygoid muscle, the nerve trunk was in direct contact with the condylar neck in every specimen. The average vertical distance between the superior condyle and the nerve was 7.06 mm (+/- 3.21 mm); the range was 0 to 13 mm. The vertical distance between the nerve and the superior condyle on one side of the specimen did not correlate with the distance on the contralateral side. CONCLUSION The auriculotemporal nerve trunk has a close anatomic relationship with the condyle and the temporomandibular joint capsular region, and there is evidence of a possible mechanism for sensory disturbances in the temporomandibular joint region. In all cases, the nerve was in direct contact with the medial aspect of the capsule or condylar neck. Because there is no correlation between the positions of the nerves on the right and left sides, only one side may be affected. The nerve was also observed to course in direct apposition to the lateral pterygoid muscle. The findings support the hypothesis that the anatomic and clinical relationship of the auriculotemporal nerve to the condyle, articular fossa, and lateral pterygoid muscle may be causally related to compression or irritation of the nerve, producing numbness or pain, or both, in the temporomandibular joint region.

A protocol for the management of failed alloplastic temporomandibular joint disc implants

PURPOSE This is a retrospective evaluation of a protocol for management of failed alloplastic temporomandibular joint (TMJ) disc implants. PATIENTS AND METHODS The criteria for implant failure were defined as any one or combination of the following symptoms and signs: TMJ pain, jaw hypomobility, occlusal changes, and radiographic evidence of bone pathology related to the implant. The protocol consisted of removal of the implant, aggressive joint debridement, recontouring of the articulating surfaces, and placement of a pedicled temporalis muscle/fascia flap (TF) for joint lining. Arch bars and maxillomandibular guiding elastics were used if extensive condylar recontouring was necessary. No attempt was made to reconstruct the condyle or correct occlusal abnormalities at the time of implant removal. All 27 patients (42 joints) treated by this protocol during the study period were included for evaluation. There were 24 Proplast/Teflon (PTI) (Vitek, Inc, Houston, TX), 11 Silastic (SI) (Dow Corning, Midland, MI), and 7 Christensen Fossa implants (CFI) (TMJ Implants, Golden, CO) implants removed. RESULTS The mean follow-up period was 38.3 months (range, 3 to 65 months). Pain was well controlled in 24 of 27 patients (88.9%). Preoperative and postoperative mean maximal incisal opening (MIO) was 32.1 mm and 39.8 mm, respectively. Two patients (7.4%) required a second TMJ operation for persistent pain and limitation of opening. To date, 7 patients (25.9%) have required a secondary procedure (unilateral vertical ramus osteotomy, n = 1; Le Fort I osteotomy, n = 6) to correct occlusal prematurity on the operated side or bilateral open bite. The remaining patients have required no additional surgical treatment. CONCLUSIONS The results of this study indicate that a proposed protocol is an effective means of controlling pain and improving jaw motion in patients with failed alloplastic TMJ disc implants.

Infection following treatment of mandibular fractures in human immunodeficiency virus seropositive patients

PURPOSE There are little data available on the prevalence of human immunodeficiency virus (HIV) disease and its relationship to postoperative infection in patients presenting with mandibular fractures. This retrospective study assesses these parameters. PATIENTS The study population consisted of 251 patients treated for mandibular fractures at San Francisco General Hospital (SFGH) between January 1990 and December 1993. Group 1 (n = 20) was composed of patients with documented HIV infection and group 2 (n = 231) served as controls. The groups were comparable with regard to age, sex, etiology, and number and types of fractures. RESULTS HIV prevalence for this population was 7.9%, and was consistent with previously documented prevalence studies in SFGH surgical patients. In the HIV-positive group, 6 of 20 patients (30%) developed postoperative infection: 2 soft tissue (10%) and 4 bone-related (20%). In the control group, 22 of 231 patients (9.5%) developed postoperative infections: 16 soft tissue (6.9%) and 6 bone-related (2.6%). Statistical analysis showed a significant difference between the two groups with regard to overall (P = .016) and to bone-related (P = .001) infection rates. There was no statistically significant difference in soft tissue infections between the two groups (P = .953). The rate of postoperative infection was significantly higher in those patients (both HIV-positive and controls) who had open reduction and internal fixation (ORIF; 25/155; 16%) versus those who had closed reduction and maxillomandibular fixation (3/96; 3.1%; P = .003). The postoperative infection rate after ORIF was significantly higher in the HIV-positive (5/11; 45%) compared with the control group (20/144; 13.9%; P = .02). CONCLUSIONS The results of this study indicate that the overall rate of postoperative infection after treatment of mandibular fractures is significantly higher in HIV-positive than in HIV-negative patients. Specifically, the use of ORIF in HIV-positive patients represents a significant risk.

Rigid fixation of mandibular fractures: Does operator experience reduce complications?

Rigid internal fixation (RIF) is a frequently used method of reduction and immobilization of mandibular fractures. It has been postulated that the unexpectedly high complication rates reported in early studies of RIF were related to operator inexperience. The objective of this study was to determine if increased operator experience with RIF would result in a lower complication rate. Two 24-month patient care periods, separated by an intervening 12 months to avoid overlap, were evaluated retrospectively. Group 1 (n = 69 patients) represented the early experience and group 2 (n = 76 patients) the more recent data. The results of the study demonstrate a downward trend in the complication rate as surgeon experience increased. This improvement, however, was not statistically significant, and other factors may play a more important role in reducing complications.

Extended genioplasty: long‐term cephalometric, morphometric and sensory results

The incision, dissection, osteotomy design and fixation are important technical considerations when performing a genioplasty. The purpose of this study was to describe an extended genioplasty technique and to evaluate stability of position, form, surface area of the chin and incidence of postoperative sensory deficit. Records of 15 consecutive adult patients who underwent the extended genioplasty procedure were reviewed. The technique included incision in the labial vestibule from 2nd premolar to 2nd premolar, dissection, mobilization and retraction of the mental nerves, osteotomy parallel to the occlusal plane extending proximally to the antegonial notch and rigid fixation. Lateral cephalograms pre- and postoperatively and at the latest follow-up (> 6 months) were analyzed by linear and computer morphometric measurements to evaluate changes in position, shape and surface area of the chin. Neurosensory data from examination or questionnaire were recorded. Immediately postoperatively (T1), mean advancement in the sagittal plane was +8.7 mm and increase in surface area was +1.1 cm2. At the end of follow-up (T2), there were no significant changes (T2-T1) in chin position or surface area. Inferior border form was rated as smooth in all cases. Neurosensory evaluation revealed that 12/12 patients evaluated had functional sensory return at T2.