Joseph Schoenaers

Skeletal stability following sagittal split osteotomy using monocortical miniplate internal fixation

Skeletal stability was evaluated in 20 patients with mandibular hypoplasia, treated with bilateral sagittal split osteotomies to advance the mandible. Stable internal fixation was obtained using osseous miniplates and monocortical screws. Intermaxillary fixation was released after 5.15 days (range 1 to 11 days). The average B-point advancement was 6.07 mm (range 2.25 to 17.5 mm) and the average Pogonion-point advancement was 5.39 mm (range 1.75 to 14 mm). Mandibular range of motion, TMJ dysfunction and neurosensory deficits were also evaluated. The follow-up period averaged 8.85 months (range 6 to 14 months) and final evaluations were made after completion of orthodontics. Relapse measured at B-point was 10.7% and at Pogonion was 18.7%. Maximal opening decreased an average of 0.47 mm. Symptoms in 8 patients with TMJ dysfunction resolved, while 3 others developed TMJ dysfunction following surgery. Neurosensory deficits were subjectively identified in 9 patients (10 sides) and were objectively measured in 5 patients (5 sides).

Atypical neurofibromas in neurofibromatosis type 1 are premalignant tumors.

Benign peripheral nerve sheath tumors (PNSTs) are a characteristic feature of neurofibromatosis type I (NF1) patients. NF1 individuals have an 8–13% lifetime risk of developing a malignant PNST (MPNST). Atypical neurofibromas are symptomatic, hypercellular PNSTs, composed of cells with hyperchromatic nuclei in the absence of mitoses. Little is known about the origin and nature of atypical neurofibromas in NF1 patients. In this study, we classified the atypical neurofibromas in the spectrum of NF1‐associated PNSTs by analyzing 65 tumor samples from 48 NF1 patients. We compared tumor‐specific chromosomal copy number alterations between benign neurofibromas, atypical neurofibromas, and MPNSTs (low‐, intermediate‐, and high‐grade) by karyotyping and microarray‐based comparative genome hybridization (aCGH). In 15 benign neurofibromas (4 subcutaneous and 11 plexiform), no copy number alterations were found, except a single event in a plexiform neurofibroma. One highly significant recurrent aberration (15/16) was identified in the atypical neurofibromas, namely a deletion with a minimal overlapping region (MOR) in chromosome band 9p21.3, including CDKN2A and CDKN2B. Copy number loss of the CDKN2A/B gene locus was one of the most common events in the group of MPNSTs, with deletions in low‐, intermediate‐, and high‐grade MPNSTs. In one tumor, we observed a clear transition from a benign‐atypical neurofibroma toward an intermediate‐grade MPNST, confirmed by both histopathology and aCGH analysis. These data support the hypothesis that atypical neurofibromas are premalignant tumors, with the CDKN2A/B deletion as the first step in the progression toward MPNST.

Prognostic index for patients with parotid carcinoma: international external validation in a Belgian-German database.

Prognostic indices for recurrence‐free interval in patients with parotid carcinoma were developed and validated in a nationwide database. International validation would increase generalizability.

Impact of Adding Concomitant Chemotherapy to Hyperfractionated Accelerated Radiotherapy for Advanced Head-and-Neck Squamous Cell Carcinoma

PURPOSE To evaluate the feasibility and efficacy of a hyperfractionated accelerated radiotherapy (RT) schedule combined with concomitant chemotherapy (Cx) in patients with locally advanced head-and-neck squamous cell carcinoma. METHODS AND MATERIALS Between 2004 and 2007, a total of 90 patients with locoregionally advanced head-and-neck squamous cell carcinoma underwent irradiation according to a hybrid fractionation schedule consisting of 20 fractions of 2 Gy (once daily) followed by 20 fractions of 1.6 Gy (twice daily) to a total dose of 72 Gy. Concomitant Cx (cisplatinum 100 mg/m(2)) was administered at the start of Weeks 1 and 4. Treatment outcome and toxicity were retrospectively compared with a previous patient group (n = 73) treated with the same schedule, but without concomitant Cx, between 2001 and 2004. RESULTS The locoregional control (LRC) rate was 70% after 2 years. Two-year overall and 2-year disease-free survival rates were 74% and 60%, respectively. In comparison with the RT-only group, an improvement of 15% in both LRC (p = 0.03) and overall survival (p = 0.09) was observed. All patients were treated to full radiation dose according to protocol, although the Cx schedule had to be adjusted in 12 patients. No acute Grade 4 or 5 toxicity was seen, but incidences of Grade 3 acute mucositis (74.5% vs. 50.7%; p = 0.002) and dysphagia (82.2% vs. 47.9%; p < 0.001) were significantly higher in the chemoradiotherapy group compared with patients treated with RT alone. CONCLUSION With this chemoradiotherapy regimen, excellent LRC and survival rates were achieved, with acceptable acute toxicity.

Late management of secondarily grafted clefts

34 patients (40 sides) received alveolo-palatal bone grafts for closure of the residual cleft, thus guiding a lateral incisor or canine into the arch. Long-term follow-up shows that in 41% of the patients uninterrupted arches were achieved with a normal relationship by orthodontic treatment only. 38% needed segmental osteotomies to eliminate the edentulous space, and in only 20% were bridges made to restore the dental arch. 9 (25%) patients still required a Le Fort I advancement osteotomy, despite optimal orthodontic treatment. The use of segmental osteotomies for eliminating edentulous spaces in cleft palate patients is discussed, and their advantage in relation to nasal base support is emphasized. It should be the aim to achieve in every cleft palate patient a complete archform without the need for bridges or removable prostheses. A rational orthodontic-surgical approach to the cleft, lip and palate patient is suggested with respect to naso-maxillary growth and development.

Reconstruction of the severely resorbed mandible with interposed bone grafts and hydroxylapatite: A 2–3 year follow-up

A follow-up study on 55 patients, who underwent an augmentation of their severely resorbed mandible, using a mixture of autogenous bone and HA-granules, is discussed. The method combines an interposed bone graft technique in the symphyseal area with a subperiosteal tunneling in the region posterior to the mental foramina. The results show a maximum height loss of approximately 30% in both the symphysis and the bicuspid-molar region after 2 to 3 years, from which most occurred in the first 6 months. The method is relatively safe with regard to potential nerve damage and provides excellent aesthetic results. The option for subsequent placement of implants is entirely possible.

Treatment of hemifacial microsomia in a growing child: the importance of co-operation between the orthodontist and the maxillofacial surgeon

The treatment of patients with hemifacial microsomia (HM) always requires an interdisciplinary approach including at least maxillofacial surgery and orthodontics. Co-operation not only within the team, but also with the patients and their family is essential in order to achieve the best results. In the case history of the 10-½ year old female patient reported here, three surgical interventions (two with costo-chondral bone grafts) and a 3-year orthodontic treatment have taken place. A harmonious facial and occlusal result was finally reached.

Novel mutations in LRP6 highlight the role of WNT signaling in tooth agenesis.

Purpose:We aimed to identify a novel genetic cause of tooth agenesis (TA) and/or orofacial clefting (OFC) by combining whole-exome sequencing (WES) and targeted resequencing in a large cohort of TA and OFC patients.Methods:WES was performed in two unrelated patients: one with severe TA and OFC and another with severe TA only. After deleterious mutations were identified in a gene encoding low-density lipoprotein receptor-related protein 6 (LRP6), all its exons were resequenced with molecular inversion probes in 67 patients with TA, 1,072 patients with OFC, and 706 controls.Results:We identified a frameshift (c.4594delG, p.Cys1532fs) and a canonical splice-site mutation (c.3398-2A>C, p.?) in LRP6, respectively, in the patient with TA and OFC and in the patient with severe TA only. The targeted resequencing showed significant enrichment of unique LRP6 variants in TA patients but not in nonsyndromic OFC patients. Of the five variants in patients with TA, two affected the canonical splice site and three were missense variants; all variants segregated with the dominant phenotype, and in one case the missense mutation occurred de novo.Conclusion:Mutations in LRP6 cause TA in humans.Genet Med 18 11, 1158–1162.

Wound Healing Problems in the Mouth

Wound healing is a primary survival mechanism that is largely taken for granted. The literature includes relatively little information about disturbed wound healing, and there is no acceptable classification describing wound healing process in the oral region. Wound healing comprises a sequence of complex biological processes. All tissues follow an essentially identical pattern to complete the healing process with minimal scar formation. The oral cavity is a remarkable environment in which wound healing occurs in warm oral fluid containing millions of microorganisms. The present review provides a basic overview of the wound healing process and with a discussion of the local and general factors that play roles in achieving efficient would healing. Results of oral cavity wound healing can vary from a clinically healed wound without scar formation and with histologically normal connective tissue under epithelial cells to extreme forms of trismus caused by fibrosis. Many local and general factors affect oral wound healing, and an improved understanding of these factors will help to address issues that lead to poor oral wound healing.

High patient satisfaction after secondary rhinoplasty in cleft lip patients

We surveyed the subjective outcome of secondary rhinoplasty in cleft lip patients.