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.

Impaired activity of the fusogenic micropeptide Myomixer causes myopathy resembling Carey-Fineman-Ziter syndrome.

Skeletal muscle fibers contain hundreds of nuclei, which increase the overall transcriptional activity of the tissue and perform specialized functions. Multinucleation occurs through myoblast fusion, mediated by the muscle fusogens Myomaker (MYMK) and Myomixer (MYMX). We describe a human pedigree harboring a recessive truncating variant of the MYMX gene that eliminates an evolutionarily conserved extracellular hydrophobic domain of MYMX, thereby impairing fusogenic activity. Homozygosity of this human variant resulted in a spectrum of abnormalities that mimicked the clinical presentation of Carey-Fineman-Ziter syndrome (CFZS), caused by hypomorphic MYMK variants. Myoblasts generated from patient-derived induced pluripotent stem cells displayed defective fusion, and mice bearing the human MYMX variant died perinatally due to muscle abnormalities. In vitro assays showed that the human MYMX variant conferred minimal cell-cell fusogenicity, which could be restored with CRISPR/Cas9-mediated base editing, thus providing therapeutic potential for this disorder. Our findings identify MYMX as a recessive, monogenic human disease gene involved in CFZS, and provide new insights into the contribution of myoblast fusion to neuromuscular diseases.

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.

INNO-LiPA DNA line probe assay misidentification of M. smegmatis as Mycobacterium fortuitum complex.

Seven weeks after being kicked in the face by a cow, a 34-year-old male patient developed a posttraumatic mycobacterial lymphadenitis. A rapidly growing mycobacterial isolate cultured from a surgically drained lymphadenitis pus specimen was identified as Mycobacterium smegmatis by matrix-assisted laser desorption/ionization mass spectrometry and a combination of ITS-, hsp65-, and 16S rRNA-DNA sequence analysis, but as Mycobacterium fortuitum complex using the commercial INNO-LiPA Mycobacteria v2 line probe assay. As it is unclear if the misidentification of this strain is an exception, more research is required.

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.

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.

Compound heterozygous NEK1 variants in two siblings with oral-facial-digital syndrome type II (Mohr syndrome).

The oral-facial-digital (OFD) syndromes comprise a group of related disorders with a combination of oral, facial and digital anomalies. Variants in several ciliary genes have been associated with subtypes of OFD syndrome, yet in most OFD patients the underlying cause remains unknown. We investigated the molecular basis of disease in two brothers with OFD type II, Mohr syndrome, by performing single-nucleotide polymorphism (SNP)-array analysis on the brothers and their healthy parents to identify homozygous regions and candidate genes. Subsequently, we performed whole-exome sequencing (WES) on the family. Using WES, we identified compound heterozygous variants c.[464G>C];[1226G>A] in NIMA (Never in Mitosis Gene A)-Related Kinase 1 (NEK1). The novel variant c.464G>C disturbs normal splicing in an essential region of the kinase domain. The nonsense variant c.1226G>A, p.(Trp409*), results in nonsense-associated alternative splicing, removing the first coiled-coil domain of NEK1. Candidate variants were confirmed with Sanger sequencing and alternative splicing assessed with cDNA analysis. Immunocytochemistry was used to assess cilia number and length. Patient-derived fibroblasts showed severely reduced ciliation compared with control fibroblasts (18.0 vs 48.9%, P<0.0001), but showed no significant difference in cilia length. In conclusion, we identified compound heterozygous deleterious variants in NEK1 in two brothers with Mohr syndrome. Ciliation in patient fibroblasts is drastically reduced, consistent with a ciliary defect pathogenesis. Our results establish NEK1 variants involved in the etiology of a subset of patients with OFD syndrome type II and support the consideration of including (routine) NEK1 analysis in patients suspected of OFD.

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.

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.

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.

Thrombophilias and adverse pregnancy outcome - A confounded problem!

It was the objective of this study to analyse the influence of confounders, such as ethnicity, severity of illness and method of testing, in articles concerning the still moot relationship of thrombophilias to adverse pregnancy outcome (APO). Relevant case-control studies were identified using Medline and EMBASE databases between 1966 and 2006. Search terms were recurrent fetal loss, intrauterine fetal death, preeclampsia, HELLP-syndrome, eclampsia, fetal growth restriction, abruptio placentae, combined with maternal thrombophilias. Data was extracted from the articles per subgroup of APO regardless of confounder. These subgroups were tested if they fulfilled the heterogeneity testing criterion (I(2) > 35%) to weigh the influence of the confounder. Confounders were selected and examined with Mantel-Haenszel method. Increased thrombophilia prevalence was confirmed in most adverse pregnancy outcomes. Ethnicity, genetic testing only and severity of illness were confounders in the various forms of APO. Stronger relationships between factor V Leiden and severity of disease were found in 2(nd) and 3(rd) trimester than 1(st) trimester recurrent fetal loss, in preeclampsia with: blood pressure > or =160/110 mmHg than > or =140/90 mmHg; proteinuria > or =5 grams per day than <5 grams; onset before than after 28 weeks, in fetal growth restriction <3(rd) percentile than <5(th), than <10(th), and in earlier occurrence of abruptio placentae than 3(rd) trimester. In conclusion, reports on the prevalence of maternal thrombophilias and APO are influenced by various confounders, which are not always appropriately analysed. The differences we have identified reflect the differential impact of these confounders. These data emphasise the importance of more uniform research.

Associations between fetal inherited thrombophilia and adverse pregnancy outcomes.

OBJECTIVE: The purpose of this study was to investigate associations between fetal inherited thrombophilia and adverse pregnancy outcomes, including pregnancy-induced hypertensive disorders (PIHD), antepartum hemorrhage (APH), small-for-gestational age <10th percentile (SGA), and preterm birth (PTB). STUDY DESIGN: Seven hundred and seventeen cases and 609 controls were genotyped for Factor V Leiden (FVL, G1691A), Prothrombin gene mutation (PGM, G20210A), and Methylenetetrahydrofolate reductase (MTHFR) C677T and MTHFR A1298C using DNA from newborn screening cards. RESULTS: For babies born <28 weeks' gestation, PGM was associated with an increased risk of SGA (OR 6.40, 95%CI 1.66-24.71) and APH with SGA (OR 6.35, 95%CI 1.63-24.75). Homozygous MTHFR A1298C was associated with an increased risk of SGA for babies born 28-31 weeks gestation (OR 4.00, 95%CI 1.04-15.37), and with APH and SGA for babies born <32 weeks' gestation (OR 3.57, 95%CI 1.09-11.66). Homozygous MTHFR C677T was associated with a reduced risk of PTB and SGA (OR 0.52, 95%CI 0.28-0.96) for babies born 32 to 36 weeks' gestation. Homozygous FVL decreased the risk of PTB <32 weeks' gestation (OR 0.55, 95%CI 0.31-0.98). CONCLUSION: Fetal thrombophilic polymorphisms may be related to adverse pregnancy outcomes, in particular SGA.