Osteoinductive calcium phosphate with submicron topography as bone graft substitute for maxillary sinus floor augmentation: A translational study.

OBJECTIVES: The aim of this study was the preclinical and clinical evaluation of osteoinductive calcium phosphate with submicron surface topography as a bone graft substitute for maxillary sinus floor augmentation (MSFA). MATERIAL AND METHODS: A preclinical sheep model of MSFA was used to compare a calcium phosphate with submicron needle-shaped topography (BCPN , MagnetOs Granules, Kuros Biosciences BV) to a calcium phosphate with submicron grain-shaped topography (BCPG ) and autologous bone graft (ABG) as controls. Secondly, a 10-patient, prospective, randomized, controlled trial was performed to compare BCPN to ABG in MSFA with two-stage implant placement. RESULTS: The pre-clinical study demonstrated that both BCPN and BCPG were highly biocompatible, supported bony ingrowth with direct bone apposition against the material, and exhibited bone formation as early as 3 weeks post-implantation. However, BCPN demonstrated significantly more bone formation than BCPG at the study endpoint of 12 weeks. Only BCPN reached an equivalent amount of bone formation in the available space and a greater proportion of calcified material (bone + graft material) in the maxillary sinus compared to the "gold standard" ABG after 12 weeks. These results were validated in a small prospective clinical study, in which BCPN was found comparable to ABG in implant stability, bone height, new bone formation in trephine core biopsies, and overall clinical outcome. CONCLUSION: This translational work demonstrates that osteoinductive calcium phosphates are promising bone graft substitutes for MSFA, whereas their bone-forming potential depends on the design of their surface features. Netherlands Trial Register, NL6436.

A Novel and Practical Protocol for Three-Dimensional Assessment of Alveolar Cleft Grafting Procedures.

OBJECTIVE: To evaluate the reproducibility and accuracy of a new, easy-to-use volumetric assessment of the alveolar cleft. DESIGN: Twelve cone-beam computed tomography (CBCT) datasets of patients with a unilateral cleft lip, alveolus, and palate were evaluated by two investigators. Residual alveolar cleft calcified volume one year after surgery was analyzed by using standardized landmarks to determine the borders of the cleft defect and semi-automatically segment the alveolar cleft defect. RESULTS: The Dice-coefficient between observers for the segmented preoperative alveolar cleft defect was 0.81. Average percentage of residual alveolar cleft calcified material was 66.7% one year postoperatively. CONCLUSIONS: This study demonstrates a reliable and practical semi-automatic three-dimensional volumetric assessment method for unilateral clefts using CBCT.

Microstructured ß-Tricalcium Phosphate Putty Versus Autologous Bone for Repair of Alveolar Clefts in a Goat Model.

For the first time it was demonstrated that an osteoinductive calcium phosphate-based putty is effective in the restoration of complex maxillofacial defects. In these defects, adequate mechanical confinement by multiple bony walls and osteoconduction from multiple surfaces are usually lacking. This study compares the efficacy of a microstructured beta-tricalcium phosphate (ß-TCP) putty with autologous bone for the repair of alveolar cleft defects. A total of 10 Dutch milk goats were operated on in a split-mouth study design in which two-wall bony alveolar clefts were created and successively repaired with autologous bone (the gold standard) at one side and ß-TCP putty at the other. After 24 weeks of implantation, histomorphometric and micro-computer tomography analyses proved that the ß-TCP putty group showed equal bone quality and volume to clefts reconstructed with autologous bone. In addition, surgical handling of the putty is superior to the use of calcium phosphates in a granular form. Therefore, the results of this study open a clear trajectory for the clinical use of ß-TCP putty in the reconstruction of the alveolar cleft and other challenging two-wall bony defects.

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.

Tissue engineering strategies for alveolar cleft reconstruction: a systematic review of the literature.

OBJECTIVES: To date, a great number of tissue engineering strategies have been suggested for alveolar cleft reconstruction; however, autologous bone grafting seems to remain the golden standard. MATERIALS AND METHODS: A systematic review of the literature was conducted in order to evaluate the clinical evidence pertaining to enhancement or replacement of the autologous bone graft in the alveolar cleft by means of tissue-engineered substitutes; 16 articles were selected for analysis. RESULTS: Tissue engineering strategies for alveolar cleft grafting included enhancing the autologous bone graft by means of platelet-rich plasma addition, the use of barrier membranes and fibrin glue, extension of the autologous graft with calcium phosphate scaffolds, and replacement of the graft using bone morphogenetic protein-2, mesenchymal stem cells, or calcium phosphate scaffolds. CONCLUSIONS: Selected articles showed a vast heterogeneity in data acquisition and patient selection. Therefore, a meta-analysis could not be performed. Future publications concerning this topic should be methodologically sound and preferably use three-dimensional radiological imaging for pre- and postoperative results. CLINICAL RELEVANCE: Bypassing or enhancing autologous bone grafting by means of tissue engineering solutions has become an important topic in alveolar cleft grafting. Replacement of the autologous bone graft will result in absence of donor site morbidity in this predominantly young population.

One-year volume stability of human facial defects filled with a ß-tricalcium phosphate-hydroxyl apatite mixture (Atlantik).

INTRODUCTION: We investigated the applicability and 1-year stability of a ß-tricalcium phosphate-hydroxyl apatite mixture (Atlantik) for secondary reconstruction of craniofacial defects and the application of OsiriX in evaluating bone and implant volumes. METHODS: We included 6 patients (25-59 years) with craniofacial defects. A computed tomography scan was made preoperative, directly postoperative, and at least 1 year postoperative to evaluate volume changes. OsiriX was used to quantify volumes of the implanted Atlantik. Measurements were performed by 2 independent investigators and analyzed by calculating both Pearson correlation and interclass correlation coefficient. RESULTS: After 1 year, the mean volume reduction of the implanted Atlantik was 9.8%. The absolute volume reduction in 1 year was 0.38 cm (range, 0.10-0.69 cm(3)). Pearson correlation test was 0.996, with a significance level of P < 0.01, and the interclass correlation coefficient was 0.998. CONCLUSIONS: Atlantik is a stable osteoconductive material for the repair of various craniofacial defects. There is a reduction of only 10% of the augmented volume in the long term. Applying OsiriX for computed tomography image volume analysis proved to be a well-reproducible technique.

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.

Clinical Practice Guidelines on the Treatment of Patients with Cleft Lip, Alveolus, and Palate: An Executive Summary.

Significant treatment variation exists in the Netherlands between teams treating patients with cleft lip, alveolus, and/or palate, resulting in a confusing and undesirable situation for patients, parents, and practitioners. Therefore, to optimize cleft care, clinical practice guidelines (CPGs) were developed. The aim of this report is to describe CPG development, share the main recommendations, and indicate knowledge gaps regarding cleft care. Together with patients and parents, a multidisciplinary working group of representatives from all relevant disciplines assisted by two experienced epidemiologists identified the topics to be addressed in the CPGs. Searching the Medline, Embase, and Cochrane Library databases identified 5157 articles, 60 of which remained after applying inclusion and exclusion criteria. We rated the quality of the evidence from moderate to very low. The working group formulated 71 recommendations regarding genetic testing, feeding, lip and palate closure, hearing, hypernasality, bone grafting, orthodontics, psychosocial guidance, dentistry, osteotomy versus distraction, and rhinoplasty. The final CPGs were obtained after review by all stakeholders and allow cleft teams to base their treatment on current knowledge. With high-quality evidence lacking, the need for additional high-quality studies has become apparent.

A novel semi-automatic segmentation protocol for volumetric assessment of alveolar cleft grafting procedures.

A novel protocol for volumetric assessment of alveolar cleft grafting procedures is presented. Eleven cone-beam computed tomography (CBCT) datasets of patients who underwent secondary alveolar cleft reconstructive surgery for a unilateral alveolar cleft were evaluated by two investigators. Residual bone volumes 1 year after surgery were analysed using a semi-automated technique in which preoperative CBCT datasets were superimposed on the postoperative scans using voxel-based registration. To define the correct boundaries of the alveolar cleft defect in the preoperative CBCT dataset, a mirror image of the preoperative CBCT dataset was superimposed on the preoperative CBCT dataset. For the difference in residual bone volume between the two observers, an intraclass correlation of 0.98 and a Dice coefficient of 0.89 were found. This study describes a reliable segmentation protocol for volumetric analysis of the alveolar cleft defect in patients with a unilateral 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.