Management of the premaxilla in the treatment of bilateral cleft of lip and palate: what can the literature tell us?

OBJECTIVE: In the treatment of bilateral cleft lip and palate (BCLP) patients, there is discussion about the management of the position of the premaxilla. This literature analysis summarises the literature on managing this condition. MATERIALS AND METHODS: A PubMed, Embase and Cochrane Library search was conducted resulting in 4465 articles which were screened on title and abstract. RESULTS: Seventy-one articles were available in full text, 16 of which were included in this literature analysis. We searched on keywords timing and technique, complications, growth of the maxilla and results after bone grafting the alveolar process. This literature analysis has shown that there are various ways to correct the position of the premaxilla. These can be divided into primary, early, late secondary and tertiary intervention before the age of 8 years, between the ages of 8 and 12 years and older than 12 years. Correction is done with surgery, orthodontics or a combination, with or without bone grafting. CONCLUSIONS: An osteotomy of the premaxilla in combination with secondary alveolar bone grafting appears to be the most successful technique. Combining early secondary alveolar bone grafting with osteotomy creates more room to ensure a watertight closure of the nasal mucosa resulting in fewer postoperative complications. Before surgery, the orthodontist should try to optimise the position of the premaxilla for its surgical correction prior to bone grafting. CLINICAL RELEVANCE: The treatment of BCLP patients is still based on experience and expert opinions. This literature analysis tries to give a summery on how to handle the protruded and displaced premaxilla.

Micro-structured Beta-Tricalcium Phosphate for Repair of the Alveolar Cleft in Cleft Lip and Palate Patients: A Pilot Study.

OBJECTIVES: Can a synthetic bone substitute be used to repair the alveolar cleft to bypass donor site morbidity as well as to shorten the operating time? In earlier experimental studies, micro-structured beta-tricalcium phosphate (ß-TCP) provided similar bone healing when compared with grafting with iliac crest bone. This justifies the clinical evaluation of this bone substitute in the human alveolar cleft situation. DESIGN: Prospective clinical study. SETTING: University clinic. PARTICIPANTS: Seven patients, all with unilateral alveolar cleft, were randomly included for alveolar cleft repair with ß-TCP in 2010 and 2011. MAIN OUTCOME MEASURES: In all patients, the alveolar cleft was repaired by micro-structured ß-TCP grafting. Our assessments were distilled from cone beam computed tomography scans taken preoperatively, 1 week postoperatively, and 6 months postoperatively. A volumetric outcome could be realized. RESULTS: Six months after the operative grafting of micro-structured ß-TCP into the alveolar cleft, the bone volume thus acquired was satisfactory. We found an average bone volume percentage of 73% ± 6% compared with the original cleft volume. CONCLUSIONS: Previous experimental and clinical studies and the initial findings of this pilot study now elucidate a path toward the clinical use of micro-structured ß-TCP bone substitute for repair of the alveolar cleft.

Micro-structured calcium phosphate ceramic for donor site repair after harvesting chin bone for grafting alveolar clefts in children.

OBJECTIVES: The purpose of this study was to evaluate the use of synthetic bone graft material as a filling material at the mandibular symphysis donor site of autologous bone in children. MATERIALS AND METHODS: A blinded patient group comprised 20 patients with unilateral (UCLP) or bilateral (BCLP) cleft of lip and palate, all with an indication for alveolar cleft repair. The study took the form of a prospective randomized clinical trial. We used lateral cephalograms for the measurement of the symphyseal donor area defect both peroperatively and at 12 months postoperatively. The data obtained were digitalized and the treatment outcome expressed in numbers. Comparisons with a previous study were made. Histology of biopsies and CT scans were used for visualising bone formation. RESULTS: This study demonstrates that the micro-structured, resorbable calcium phosphate ceramic provides good regeneration properties for the repair of a critical size bony defect in children. One year postoperatively, the measurements taken from lateral cephalograms show that there is scarcely any visible residual defect. Histological investigations of the bone biopsies show solid, induced bone formation and almost complete resorption of the micro-structured calcium phosphate. CONCLUSIONS: The findings of this study (novel in children) indicate that micro-structured resorbable calcium phosphate is an excellent alternative to autologous bone. The digital findings showed a restored donor site defect significantly indicating the efficacy (i.e., osteoconductivity and resorbability) of this bone substitute. The biopsy histology demonstrated the overall presence of newly formed vital bone and the resorption of the bone substitute. Its use for grafting the alveolar cleft is currently researched and it may become the new standard. CLINICAL RELEVANCE: As co-morbidity and prolonged operation time at the donor operation site are inherent to the alveolar cleft repair procedure, the use of the described bone substitute is winning progress.

ß-TCP versus autologous bone for repair of alveolar clefts in a goat model.

OBJECTIVE: The aim of this study in goats was to test the hypothesis that a novel synthetic bone substitute beta tricalcium phosphate (ß-TCP) can work as well as autologous bone harvested from the iliac crest for grafting and repair of alveolar clefts. DESIGN: Ten adult Dutch milk goats (Capra hircus) were used in a split-mouth study design. MAIN OUTCOME MEASURES: Volumetric histologic assessment of new bone formation and radiographic measurement of orthodontic movement of teeth in a formerly created alveolar cleft. CONCLUSIONS: The synthetic bone substitute ß-TCP was shown to result in bone healing similar to that of iliac crest bone. The surgical, orthodontic, and histologic results now warrant the testing of ß-TCP in the human cleft situation.

Osteoinductive ceramics as a synthetic alternative to autologous bone grafting.

Biomaterials can be endowed with biologically instructive properties by changing basic parameters such as elasticity and surface texture. However, translation from in vitro proof of concept to clinical application is largely missing. Porous calcium phosphate ceramics are used to treat small bone defects but in general do not induce stem cell differentiation, which is essential for regenerating large bone defects. Here, we prepared calcium phosphate ceramics with varying physicochemical and structural characteristics. Microporosity correlated to their propensity to stimulate osteogenic differentiation of stem cells in vitro and bone induction in vivo. Implantation in a large bone defect in sheep unequivocally demonstrated that osteoinductive ceramics are equally efficient in bone repair as autologous bone grafts. Our results provide proof of concept for the clinical application of "smart" biomaterials.

Orthodontic treatment results following grafting autologous mandibular bone to the alveolar cleft in patients with a complete unilateral cleft.

OBJECTIVE: To analyze orthodontic treatment results following mandibular symphysis bone grafting and postoperative orthodontic treatment. DESIGN: Randomized selection of 75 patients out of 308 with unilateral cleft of lip, alveolus, and palate, operated upon according to protocol between 1990 and 2008 in the Wilhelmina Children's Hospital, Utrecht, The Netherlands. MAIN OUTCOME MEASURE: Goslon Yardstick rating changes of dental arch relationship. Significant agreement (p < .001) was observed between the two assessments carried out with an interval of 3 months (Cohen's kappa = .963, p < .001). RESULTS: Following mandibular bone grafting and orthodontic treatment in 65.3% of the patients, the aim of treatment (Goslon Yardstick groups 1 and 2) had been achieved. The applied before/after Goslon allocations showed high improvement significance (p < .001). CONCLUSIONS: Postoperative orthodontic treatment in patients following grafting with mandibular symphysis bone showed excellent results.