Mandibular reconstruction using intraoral microvascular anastomosis following removal of an ameloblastoma.

Ameloblastoma is a histologically benign, locally aggressive tumor arising from the odontogenic ectoderm. It accounts for 1% of all oral tumors and for 9% to 11% of all odontogenic tumors. In up to 96.6%, the tumor can be found in the mandible, predominantly in the molar region. High recurrence rates of up to 90% have been described with conservative treatment. Recurrences most often occur after 2 to 5 years. After radical resection, significantly lower recurrence rates have been reported, sometimes as low as 3.6%. As a consequence, when recurrence rate is the main concern, there is a tendency to prefer radical resection of the ameloblastoma. Microvascular segmental reconstruction of the mandible that uses an intraoral anastomosis technique has not been described in the current literature. Therefore, the present study aimed at extending the armamentarium of bony microvascular reconstruction in cases of segmental mandibulectomy by describing an intraoral microvascular anastomosing technique.

Vestibuloplasty: porcine collagen matrix versus free gingival graft: a clinical and histologic study.

BACKGROUND: A free gingival graft (FGG) is currently the gold standard for augmenting small areas of keratinized mucosa. The porcine collagen matrix (CM) represents an alternative to autologous tissue harvesting. This study aims to compare the CM versus FGGs for augmenting keratinized peri-implant mucosa based on clinical and histologic evaluations. METHODS: The study included 14 patients who underwent a vestibuloplasty with either a FGG from the palate (n = 7) or the CM (n = 7). An implant-fixed vestibular retention splint was inserted for 30 days. Follow-up examinations were performed at 4, 10, 30, and 90 days after surgery. Width of keratinized mucosa was measured in the region of each implant (days 10, 30, and 90). After 90 days, a biopsy was harvested for histologic and immunohistologic analyses. To characterize newly formed soft tissue, the authors stained for tissue-and differentiation-specific markers, cytokeratin (CK) 5/6, 13, and 14, to detect presence or absence of keratinization. RESULTS: The groups showed similar healing, with increased peri-implant keratinized mucosa. The CM group had overall significantly shorter operation times than the FGG group. Both groups showed similar overall shrinkage (32.98% CM versus 28.35% FGG). All biopsies showed a multilayered, keratinized, squamous epithelium. CKs 5/6 and 14 were detected in the basal and suprabasal layers, and spots of CK 13 were detected in the suprabasal layer. CONCLUSIONS: During the whole observation period, both groups showed comparable clinical and histologic outcomes. Within the limitations of the present study, CM seems to be a promising alternative for the regeneration of keratinized mucosa without tissue harvesting. Comparative long-term studies are needed to investigate changes over time.

Patient-centred outcomes comparing transmucosal implant placement with an open approach in the maxilla: a prospective, non-randomized pilot study.

It was the aim of the study to assess differences in patient morbidity between transmucosal implant placement and implant installation after elevation of mucoperiosteal flaps. In five of the patients, implants were placed in the maxilla transmucosally using a CAD/CAM surgical template [test group (TG)]. In the remaining five patients, the implants were installed after the elevation of mucoperiosteal flaps [control group (CG)]. Directly after surgery, at days 1 and 7 after surgery the patients rated pain and discomfort on a visual analogue scale (0=minimal pain and discomfort, 100=maximal pain and discomfort). Optical three-dimensional images were assessed preoperatively and at days 1 and 7 after surgery to determine the visible soft tissue swelling of the upper lip and cheeks. Directly postoperatively, the mean pairwise difference between both groups in view of pain and discomfort ratings (control minus test) was 45.6 (SD, 20.7). At days 1 and 7, the mean differences were 51.6 (SD, 21.8) and 19 (SD, 8), respectively. The overall test of the area under curve (AUC) against the null hypothesis 'AUC of pairwise differences of pain score over study time equals null' yielded a significant difference (P=0.01). The mean pairwise difference between both groups in view of soft tissue volume increase was 6.1 (SD, 2) cm(3) at day 1 after surgery and 4.6 (SD, 1.2) cm(3) at day 7. The overall test of the AUC against the null hypothesis 'AUC of pairwise differences of oedema measurements over study time equals null' yielded a significant difference (P=0.002). Within the limitations of this pilot study, it could be shown that transmucosal implant placement reduces patient morbidity significantly compared with an open approach.

Clinical trial of modified ankylos implants for extraoral use in cranio- and maxillofacial surgery.

PURPOSE: Epithetic solutions in the maxillofacial region are indicated if plastic surgery reconstruction is not a valid option for an extensive defect. The purpose of this study was to examine whether the extraoral implants used provided sufficient retention to be used as anchoring aids. MATERIALS AND METHODS: Between November 1999 and September 2002, 33 identical modified Ankylos implants for extraoral anchorage were placed in 10 patients for the fixation of various epitheses in the midfacial (eye, nose) and ear regions in the course of a clinical trial. RESULTS: Over a follow-up period of 2 to 34 months, all implants remained osseointegrated (as confirmed radiographically), and the implants and epithetic restorations were clinically stable. DISCUSSION: The results demonstrated that the lasting retention of maxillofacial epitheses provided by implants assures patients that their epitheses are securely fixed. CONCLUSION: The demonstrated extraoral implant system not only achieved sufficient osseointegration but also showed good clinical handling and easy fixation possibilities for epithetic anchorage.