Oral Health in the Down Syndrome Population: Parental Perceptions on Dental Care in the United States.

Purpose: To assess the oral health status of children with Down syndrome (DS) in the United States and evaluate the oral health needs of families with DS. Methods: Among 320 parents who consented to participate, 260 (81.2 percent) surveys were completed. A survey was distributed through the National Down Syndrome Society to parents of children with DS up to age 21 years, which asked questions about children's general and oral health. Results: Parents who reported that their children had difficulty rinsing and spitting were more likely to report their child's overall general health as poor (P<0.05). Parents' frequency of daily toothbrushing was similar to their children's toothbrushing habits (P<0.05). Conclusions: Dysphagia for children with Down syndrome may negatively impact oral health in addition to general health. Encouraging parental involvement in oral care for children with DS may lower their risk for oral disease. Continued support is needed to ensure dental school education includes training for the treatment and management of patients with DS.

The Challenges and Rewards of Teledentistry.

On March 15, 2020, routine dental care in New York State paused due to the COVID-19 pandemic. The pause lasted 10 weeks in part to preserve critical supplies of personal protective equipment (PPE). This interruption of access to dental care led to an overall deterioration of oral health, an increase in prescribing and use of antibiotics and analgesic medications, especially opiates, and a rise in visits to hospital emergency centers. New York University's College of Dentistry, an academic ambulatory dental center, normally sees over 1,000 patient visits per day. Most visits are patients who require urgent care or are in the process of treatment to restore debilitating oral health problems. NYU Dentistry responded to the State pause by creating a nascent teledentistry service that began operations on March 17, 2020.

The Impact of an Interprofessional Pediatric Oral Health Clerkship on Advancing Interprofessional Education Outcomes.

The aim of this study was to evaluate the effectiveness of an innovative pediatric interprofessional education clinical experience using oral-systemic health as the clinical population example for improving the self-reported interprofessional competencies of family nurse practitioner, dental, and medical students. The objectives of the interprofessional experience were for students to apply pediatric oral health assessment, identify the pediatric oral-systemic connection, and practice a team-based approach to improve oral-systemic outcomes. In spring 2015, fall 2015, and spring 2016, a total of 162 family nurse practitioner, dental, and medical students participated in this interprofessional experience at Bellevue Pediatric Outpatient Clinics together with a pediatric dental resident. Team members collaborated in reviewing the patient chart, taking the patient's medical and dental history, performing an oral assessment, applying fluoride varnish, and providing education and anticipatory guidance. The Interprofessional Collaborative Competency Attainment Survey (ICCAS) was used as a pretest and posttest to evaluate the degree to which students perceived changes in their attitudes about interprofessional competencies following the learning experience. In the results, all students had improved mean scores from pretest to posttest after the experience, and these changes were statistically significant for all students: nurse practitioner (p<0.01), dentistry (p<0.01), and medicine (p<0.001). The mean change from pretest to posttest was statistically significant for each of the six interprofessional competency domains (p<0.01). In both pediatric dental and primary care settings, the changes from pre- to posttest were significant (p<0.001). The experience was similarly effective for all groups of students in increasing their attitudes about interprofessional collaboration. These findings suggest that a clinical approach can be an effective strategy for helping health professions students develop interprofessional competence.

Differential regulation of Ca2+ influx by ORAI channels mediates enamel mineralization.

Store-operated Ca2+ entry (SOCE) channels are highly selective Ca2+ channels activated by the endoplasmic reticulum (ER) sensors STIM1 and STIM2. Their direct interaction with the pore-forming plasma membrane ORAI proteins (ORAI1, ORAI2, and ORAI3) leads to sustained Ca2+ fluxes that are critical for many cellular functions. Mutations in the human ORAI1 gene result in immunodeficiency, anhidrotic ectodermal dysplasia, and enamel defects. In our investigation of the role of ORAI proteins in enamel, we identified enamel defects in a patient with an ORAI1 null mutation. Targeted deletion of the Orai1 gene in mice showed enamel defects and reduced SOCE in isolated enamel cells. However, Orai2-/- mice showed normal enamel despite having increased SOCE in the enamel cells. Knockdown experiments in the enamel cell line LS8 suggested that ORAI2 and ORAI3 modulated ORAI1 function, with ORAI1 and ORAI2 being the main contributors to SOCE. ORAI1-deficient LS8 cells showed altered mitochondrial respiration with increased oxygen consumption rate and ATP, which was associated with altered redox status and enhanced ER Ca2+ uptake, likely due to S-glutathionylation of SERCA pumps. Our findings demonstrate an important role of ORAI1 in Ca2+ influx in enamel cells and establish a link between SOCE, mitochondrial function, and redox homeostasis.

Rescue of Premature Coronal Suture Fusion with TGF-ß2 Neutralizing Antibody in Rabbits with Delayed-Onset Synostosis.

OBJECTIVES: An overexpression of Tgf-ß2 leads to calvarial hyperostosis and suture fusion in individuals with craniosynostosis. Inhibition of Tgf-ß2 may help rescue fusing sutures and restore normal growth. The present study was designed to test this hypothesis. DESIGN: Twenty-eight New Zealand White rabbits with delayed-onset coronal synostosis had radiopaque markers placed on either side of the coronal sutures at 10 days of age. The rabbits were randomly assigned to: (1) sham control rabbits (n = 10), (2) rabbits with control IgG (100 µg/suture) delivered in a collagen vehicle (n = 9), and (3) rabbits with Tgf-ß2 neutralizing antibody (100 µg/suture) delivered in a collagen vehicle (n = 9). Longitudinal growth data were collected at 10, 25, 42, and 84 days of age. Sutures were harvested at 84 days of age for histomorphometry. RESULTS: Radiographic analysis showed significantly greater ( P < .05) coronal suture marker separation, craniofacial length, cranial vault length, height, shape indices, cranial base length, and more lordotic cranial base angles in rabbits treated with anti-Tgf-ß2 antibody than in controls at 42 and 84 days of age. Histologically, rabbits treated with anti-Tgf-ß2 antibody at 84 days of age had patent and significantly ( P < .05) wider coronal sutures and greater sutural area compared to controls. CONCLUSIONS: These data support our hypothesis that antagonism of Tgf-ß2 may rescue fusing coronal sutures and facilitate craniofacial growth in this rabbit model. These findings also suggest that cytokine therapy may have clinical significance in infants with progressive postgestational craniosynostosis.

Efficient in vivo gene delivery using modified Tat peptide with cationic lipids.

A combination of modified HIV-1 Tat (mTat) peptide and cationic lipids, FuGENE HD (FH), dramatically enhanced transfection efficiency across a range of cell lines when compared to mTat or FH alone (Biomaterials 35:1705-1715 2014). The efficiency of this Tat peptide combination was significantly higher than many commercial non-viral vectors. In this present study, we tested the feasibility of this non-viral vector, mTat/FH, in vivo using plasmid DNA encoding a luciferase gene. The results of the in vivo studies showed that animals administered mTat/FH/DNA intramuscularly had significantly higher and longer luciferase expression (≈7 months) than those with mTat/DNA, FH/DNA, or DNA alone. Histological evaluation showed little immune response in the muscles, livers, and kidneys of mice administered with the mTat/FH. The combination of mTat with FH could significantly improve transfection efficiency, expanding the potential use of non-viral gene vectors in vivo.

The effect of a bioactive collagen membrane releasing PDGF or GDF-5 on bone regeneration.

Regenerative procedures using barrier membrane technology are presently well established in periodontal/endodontic surgery. The objective of this study was to compare the subsequent effects of the released platelet-derived growth factor (PDGF) and growth/differentiation factor 5 (GDF-5) from collagen membranes (CMs) on bone regeneration in vitro and in vivo. In vitro studies were conducted using MC3T3-E1 mouse preosteoblasts cultured with or without factors. Cell viability, cell proliferation, alkaline phosphatase (ALP) activity and bone marker gene expression were then measured. In vivo studies were conducted by placing CMs with low or high dose PDGF or GDF-5 in rat mandibular defects. At 4 weeks after surgery new bone formation was measured using µCT and histological analysis. The results of in vitro studies showed that CM/GDF-5 significantly increased ALP and cell proliferation activities without cytotoxicity in MC3T3-E1 cells when compared to CM/PDGF or CM alone. Gene expression analysis revealed that Runx2 and Osteocalcin were significantly increased in CM/GDF-5 compared to CM/PDGF or control. Quantitative and qualitative µCT and histological analysis for new bone formation revealed that although CM/PDGF significantly enhanced bone regeneration compared to CM alone or control, CM/GDF-5 significantly accelerated bone regeneration to an even greater extent than CM/PDGF. The results also showed that GDF-5 induced new bone formation in a dose-dependent manner. These results suggest that this strategy, using a CM carrying GDF-5, might lead to an improvement in the current clinical treatment of bone defects for periodontal and implant therapy.

Long-term efficient gene delivery using polyethylenimine with modified Tat peptide.

Polyethylenimine (PEI), a cationic polymer, has been widely studied and shown great promise as an efficient gene delivery vehicle. Likewise, the HIV-1 Tat peptide, a cell-permeable peptide, has been successfully used for intracellular gene delivery. To improve the favorable properties of these two vectors, we combine PEI with the modified Tat peptide sequence bearing histidine and cysteine residues (mTat). In vitro mTat/PEI-mediated transfection was evaluated by luciferase expression plasmid in two cell types. mTat/PEI produced significant improvement (≈5-fold) in transfection efficiency of both cell lines with little cytotoxicity when compared to mTat alone, PEI alone, or four commercial reagents. The particle size of mTat/PEI/DNA complex was significantly smaller than mTat or PEI alone, and it was correlated with higher transfection efficiency. Filipin III, an inhibitor of caveolae-mediated endocytosis, significantly inhibited mTat/PEI transfection. In contrast, chlorpromazine, an inhibitor of clathrin-mediated endocytosis, did not. This suggested caveolae-mediated endocytosis as the transfection mechanism. Furthermore, the results of in vivo studies showed that animals administered mTat/PEI/DNA intramuscularly had significantly higher and longer luciferase expression (≈7 months) than those with mTat/DNA, PEI/DNA, or DNA alone, without any associated toxicity. The combination of mTat with PEI could significantly improve transfection efficiency, expanding the potential use as a non-viral gene vector both in vitro and in vivo.

Delivery of Transforming Growth Factor-ß3 Plasmid in a Collagen Gel Inhibits Cranial Suture Fusion in Rats.

Objective : Studies described in this paper were designed to test the hypothesis that an increase in nonviral, plasmid-encoded Tgf-ß3 production, localized to the rat posterior frontal suture, prevents programmed suture fusion. Design : We developed a gene delivery system based on a dense collagen gel to deliver nonviral plasmids that encode for Tgf-ß3. Studies were performed to test the ability of this system to rescue rat cranial suture fusion in vitro and in vivo. Immunohistochemical studies were conducted to characterize the possible mechanisms by which increased production and presence of Tgf-ß3 protein interferes with suture fusion. Results : Posterior frontal sutures in the Tgf-ß3 plasmid-treated group exhibited 77% to 85% less bony bridging than the collagen control and untreated groups after 15 days in culture. In animals treated with Tgf-ß3 plasmid or Tgf-ß3 protein, there was a significant reduction in suture fusion in the middle region of the posterior frontal sutures when compared with control groups. In this region the Tgf-ß3 plasmid-treated group revealed 70% to 75% less bony bridging than control groups in vivo. Conclusions : Collagen gel can be formulated to provide release of nonviral plasmid DNA that results in cell transfection and elevated Tgf-ß3 protein production. Tgf-ß3 is an important regulator of suture fusion, and an increase in plasmid-encoded Tgf-ß3 protein is effective in inhibiting programmed suture fusion in rats.

Relaxin does not rescue coronal suture fusion in craniosynostotic rabbits.

OBJECTIVES: Craniosynostosis affects 1 in 2000 to 3000 live births and may result in craniofacial and neural growth disturbances. Histological data have shown that thick collagenous bundles are present in the sutural ligament, which may tether the osteogenic fronts, resulting in premature fusion. The hormone relaxin has been shown to disrupt collagen fiber organization, possibly preventing craniosynostosis by relaxing the sutural ligament and allowing osteogenic fronts to separate normally and stay patent. This study tested this hypothesis with a rabbit model of delayed-onset coronal suture synostosis. METHODS: A total of 18 New Zealand White rabbits with craniosynostosis were randomly assigned to one of three groups: sham control, protein control (BSA), relaxin treatment. After initial diagnosis, sham surgery, BSA, or relaxin was delivered to the fusing coronal suture in a slow-release (56-day) collagen vehicle. Longitudinal radiographs and body weights were collected at 10, 25, 42, and 84 days of age, and sutures were harvested for histology. RESULTS: Relaxin-treated animals had more disorganized intrasuture content than control groups. These specimens also appeared to have relatively wider sutures ectocranially. There were no significant differences in relaxin-treated animals for all craniofacial growth measures, or suture separation compared with controls. CONCLUSIONS: These data do not support our initial hypothesis that the use of relaxin may rescue sutures destined to undergo premature suture fusion. These findings suggest that collagen fiber arrangement may not be important for suture fusion. This protein therapy would not be clinically useful for craniosynostosis.

Blocking bone morphogenetic protein function using in vivo noggin therapy does not rescue premature suture fusion in rabbits with delayed-onset craniosynostosis.

BACKGROUND: Craniosynostosis is defined as the premature fusion of one or more cranial sutures. Bone morphogenetic proteins (BMPs), regulators of ossification, have been implicated in premature suture fusion. Noggin, an extracellular BMP inhibitor, has been shown experimentally to inhibit resynostosis following surgery. The present study was designed to test the hypothesis that BMP inhibition using noggin therapy may rescue sutures destined to fuse by inhibiting initial ossification. METHODS: Twenty-six, 10-day old rabbits with familial, delayed-onset, coronal suture synostosis were randomly divided into three groups: (1) the sham surgical control group, (2) the bovine serum albumin-treated group [10 µg/suture (protein/vehicle controls)], and (3) the noggin therapy group (10 µg/suture; experimental group). Sutural growth was monitored by radiopaque markers implanted at 10 days of age. At 25 days, the bovine serum albumin or noggin was combined with a slow-resorbing collagen vehicle and injected subperiosteally above the coronal suture. Somatic and sutural growth data were collected at 10, 25, 42, and 84 days of age. Coronal sutures were harvested at 84 days to histologically assess fusion. RESULTS: Results showed no significant (p > 0.05) differences in suture separation at any age. Suture fusion assessed by histomorphology did not differ among the three groups. Although previous data showed noggin to inhibit postoperative resynostosis in this craniosynostotic rabbit model, here there was no effect on initial suture fusion. CONCLUSION: These results suggest that in this rabbit model of craniosynostosis, BMPs do not play a role in the pathogenesis of craniosynostosis and only play a role in postoperative bony wound healing.

Modified Tat peptide with cationic lipids enhances gene transfection efficiency via temperature-dependent and caveolae-mediated endocytosis.

The HIV-1 Tat peptide has been successfully used for intracellular gene delivery. Likewise, various lipid-based methods have shown increased endocytosis and can influence endosomal escape. This study combines the favorable properties of Tat peptide with that of lipid systems for DNA delivery. We combined the lipid FuGENE HD (FH) with the Tat peptide sequence modified with histidine and cysteine residues (mTat). mTat/FH transfection was evaluated by luciferase expression plasmid in five cell types. mTat/FH produced significant improvement in transfection efficiency of all cell lines when compared to FH or mTat. Treatment with chloroquine, associated with energy-dependent endocytosis, significantly increased transfection efficiency with mTat/FH while incubation at low temperature decreased it. The zeta potential of mTat/FH/DNA was significantly higher compared to FH, mTat, or their DNA combination in the presence of serum, and it was correlated with transfection efficiency. The particle size of the FH/DNA complex was significantly reduced by addition of mTat. Filipin III, an inhibitor of caveolae-mediated endocytosis, significantly inhibited mTat/FH transfection, but transfection was increased by chlorpromazine, an inhibitor of clathrin-mediated endocytosis. These findings demonstrated the feasibility of using a combination of mTat with lipids, utilizing temperature-dependent and caveolae-mediated endocytosis, as a potentially attractive non-viral gene vector.

Use of mobile electronic devices as educational tool in pediatric community outreach.

The introduction of mobile electronic devices, as opposed to paper forms, in pediatric outreach programs of the New York University College of Dentistry is discussed. Since 2007, students have been receiving training on how to operate a personal digital assistant (PDA) and use it in community outreach for non-invasive oral-facial screenings and patient education. The shift from using paper forms to electronic media had a positive impact among the academic community, as it resulted in saving time and reducing the possibility of data collection errors. It may represent a significant improvement in data collection and patient education; and it provides an opportunity to enhance research and quality assessment.

Nutrition and oral health considerations in children with special health care needs: implications for oral health care providers.

Children with special health care needs are at increased risk for oral diseases. The purpose of this article was to discuss: nutritional and oral health factors routinely observed in most chronic childhood disorders; dietary modifications associated with select systemic disorders and how they may impact oral health in children; and the following factors common to chronic disorders associated with diet modifications-decreased appetite and increased nutritional risk; frequency of food intake; parental overindulgence; long-term use of cariogenic medications; and xerostomia. Characteristics of childhood disorders that require dietary modifications (congenital heart disease, cystic fibrosis, cancer, AIDS/HIV, diabetes mellitus, and phenylketonuria) are summarized. In addition, healthy dietary modifications and oral health recommendations are suggested. Implementation of these recommendations can assist the dentist and dental team as they join physicians and nutritionists in delivering the best possible care to children with special health care needs.

Comparison of transfection efficiency of nonviral gene transfer reagents.

This study compared six commercially available reagents (Arrest-In, ExpressFect, FuGENE HD, jetPEI, Lipofectamine 2000, and SuperFect) for gene transfection. We examined the efficiency and cytotoxicity using nine different cell lines (MC3T3-E1 mouse preosteoblasts, PT-30 human epithelial precancer cells, C3H10T1/2 mouse stem cells, MCF-7 human breast cancer cells, HeLa human cervical cancer, C2C12 mouse myoblasts, Hep G2 human hepatocellular carcinoma, 4T1 mouse mammary carcinoma, and HCT116 human colorectal carcinoma), and primary cells (HEKn human epidermal keratinocytes) with two different plasmid DNAs encoding luciferase or ß-galactosidase in the presence or absence of serum. Maximal transfection efficiency in MC3T3-E1, C3H10T1/2, HeLa, C2C12, Hep G2, and HCT116 was seen using FuGENE HD, in PT-30, 4T1, and HEKn was seen using Arrest-In, and in MCF-7 was seen using jetPEI. Determination of cytotoxicity showed that the largest amount of viable cells was found after transfection with jetPEI and ExpressFect. These results suggest that FuGENE HD is the most preferred transfection reagent for many cell lines, followed by Arrest-In and jetPEI. These results may be useful for improving nonviral gene and cell therapy applications.

Public-private collaboration to improve oral health status of children enrolled in Head Start in New York City.

A comprehensive oral health care program for Head Start children in New York City is described. Head Start is a federally funded pre-school program for low-income families and their children. It provides activities that help children grow mentally, socially, emotionally and physically. In 1994, a public-private partnership was created between New York Administration for Children's Services and New York University College of Dentistry. The program consists of periodic visits to different Head Start centers by a dental team composed of pediatric dentists, residents, hygienists and students. At the center, the team provides diagnostic and preventive services to children and oral health education to children, parents and staff. Referrals are then made to the College of Dentistry or to a community provider for treatment and follow-up. Free transportation is provided between Head Start centers and the college clinic. Over 13 years, 25,000 children have received diagnostic, preventive and treatment services.

Anti-TGF-beta2 antibody therapy inhibits postoperative resynostosis in craniosynostotic rabbits.

BACKGROUND: Postoperative resynostosis is a common clinical finding. It has been suggested that an overexpression of transforming growth factor (TGF)-beta2 may be related to craniosynostosis and may contribute to postoperative resynostosis. Interference with TGF-beta2 function with the use of neutralizing antibodies may inhibit resynostosis. The present study was designed to test this hypothesis. METHODS: New Zealand White rabbits with bilateral coronal suture synostosis were used as suturectomy controls (group 1, n = 9) or given suturectomy with nonspecific, control immunoglobulin G antibody (group 2, n = 9) or suturectomy with anti-TGF-beta2 antibody (group 3, n = 11). At 10 days of age, a 3 x 15-mm coronal suturectomy was performed. The sites in groups 2 and 3 were immediately filled with 0.1 cc of a slowly resorbing collagen gel mixed with either immunoglobulin G (100 mug per suture) or anti-TGF-beta2 (100 mug per suture). Three-dimensional computed tomography scan reconstructions of the defects were obtained at 10, 25, 42, and 84 days of age, and the sutures were harvested for histomorphometric analysis. RESULTS: Computed tomography scan data revealed that the suturectomy sites treated with anti-TGF-beta2 showed significantly (p < 0.05) greater areas through 84 days of age compared with controls. Histomorphometry also showed that suturectomy sites treated with anti-TGF-beta2 had patent suturectomy sites and more fibrous tissue in the defects compared with sites in control rabbits and had significantly (p < 0.001) less new bone area (by approximately 215 percent) in the suturectomy site. CONCLUSIONS: These data support the initial hypothesis that interference with TGF-beta2 function inhibited postoperative resynostosis in this rabbit model. They also suggest that this biologically based therapy may be a potential surgical adjunct to retard postoperative resynostosis in infants with craniosynostosis.

Noggin inhibits postoperative resynostosis in craniosynostotic rabbits.

UNLABELLED: Inhibition of bone formation after surgery to correct craniosynostosis would alleviate the need for secondary surgeries and decrease morbidity and mortality. This study used a single dose of Noggin protein to prevent resynostosis and improve postoperative outcomes in a rabbit model of craniosynostosis. INTRODUCTION: Craniosynostosis is defined as the premature fusion of one or more of the cranial sutures, which causes secondary deformations of the cranial vault, cranial base, and brain. Current surgical intervention involves extirpation of the fused suture to allow unrestricted brain growth. However, resynostosis of the extirpated regions often occurs. Several bone morphogenetic proteins (BMPs), well-described inducers of ossification, are involved in bone healing. This study tested the hypothesis that a postoperative treatment with Noggin, an extracellular BMP inhibitor, can inhibit resynostosis in a rabbit model of human familial nonsyndromic craniosynostosis. MATERIALS AND METHODS: Thirty-one New Zealand white rabbits with bilateral coronal suture synostosis were divided into three groups: (1) suturectomy controls (n = 13); (2) suturectomy with BSA in a slow-resorbing collagen vehicle, (n = 8); and (3) suturectomy with Noggin in a slow-resorbing collagen vehicle (n = 10). At 10 days of age, a 3 x 15-mm coronal suturectomy was performed. The sites in groups 2 and 3 were immediately filled with BSA-loaded gel or Noggin-loaded gel, respectively. Serial 3D-CT scan reconstructions of the defects and standard radiographs were obtained at 10, 25, 42, and 84 days of age, and the sutures were harvested for histological analysis. RESULTS: Radiographic analysis revealed that Noggin-treated animals had significantly greater coronal suture marker separation by 25 days and significantly greater craniofacial length at 84 days of age compared with controls. 3D-CT analysis revealed that Noggin treatment led to significantly greater defect areas through 84 days and to increased intracranial volumes at 84 days of age compared with other groups. Histological analysis supported CT data, showing that the untreated and BSA-treated groups had significant healing of the suturectomy site, whereas the Noggin-treated group had incomplete wound healing. CONCLUSIONS: These data support our hypothesis that inhibition of BMP activity using Noggin may prevent postoperative resynostosis in this rabbit model. These findings also suggest that Noggin therapy may have potential clinical use to prevent postoperative resynostosis in infants with craniosynostosis.

Postoperative anti-Tgf-beta2 antibody therapy improves intracranial volume and craniofacial growth in craniosynostotic rabbits.

Postoperative resynostosis and secondary craniofacial growth abnormalities are common sequelae after craniofacial surgery. It has been suggested that an overexpression of transforming growth factor-beta2 (Tgf-beta2) may be related to craniosynostosis and contribute to postoperative resynostosis. Interference with Tgf-beta2 function using neutralizing antibodies may inhibit resynostosis and improve postoperative craniofacial growth; the present study was designed to test this hypothesis. Twenty-nine New Zealand white rabbits with bilateral coronal suture synostosis were used: 1) suturectomy controls (n=9); 2) suturectomy with nonspecific, control IgG antibody (n=9); and 3) suturectomy with anti-Tgf-beta2 antibody (n=11). At 10 days of age, a 3 mm x 15-mm coronal suturectomy was performed. The sites in groups 2 and 3 were immediately filled with 0.1 cc of a slow resorbing collagen gel mixed with either IgG (100 microg/suture) or anti-Tgf-beta2 (100 microg/suture). Three-dimensional computed tomography scan reconstructions of the skulls and cephalographs were obtained at 10, 25, 42, and 84 days of age. Computed tomography scan data revealed patent suturectomy sites and significantly (P<0.05) greater intracranial volumes by 84 days of age in rabbits treated with anti-Tgf-beta2 compared with controls. Cephalometric analysis revealed significant (P<0.05) differences in craniofacial, cranial vault, and cranial base growth by 84 days of age in rabbits treated with anti-Tgf-beta2 compared with controls. These data support the initial hypothesis that interference with Tgf-beta2 function inhibited postoperative resynostosis and improved cranial vault growth in this rabbit model. Thus, this biologically based therapy may be a potential surgical adjunct in the treatment of infants with craniosynostosis.

Sustained delivery of bioactive cytokine using a dense collagen gel vehicle collagen gel delivery of bioactive cytokine.

OBJECTIVE: The use of cytokines as localized therapeutic agents is limited by the lack of a satisfactory delivery system. The aim of the current investigation was to determine the release kinetics and bioactivity of a simplified cytokine/collagen gel system designed to achieve extended, local delivery of bioactive cytokines at sites of premature cranial suture fusion (craniosynostosis). DESIGN: Cytokine release was determined by ELISA measurements of Tgf-beta3 collected in media. Cytokine bioactivity was determined by measuring the effect of conditioned media, containing released Tgf-beta3, on mink lung epithelial cell proliferation and osteoblast alkaline phosphatase activity. Osteoblast response was evaluated by measuring proliferation of cells cultured on collagen gel containing Tgf-beta3 using an AlamarBlue assay. RESULTS: Gels loaded with 100 and 500 ng of Tgf-beta3 produced a sustained release over 14 days with a pattern of initial large release followed by a gradual reduction in the amount released over the time. The reduced release over time was correlated to the amount initially loaded. Mink lung epithelial cell assay results indicated that Tgf-beta3 released from the collagen gel retained its bioactivity following incorporation into the collagen gel and release into the media. This bioactivity was further illustrated by a decreased alkaline phosphatase activity measured in osteoblasts cultured on the gels loaded with Tgf-beta3. Osteoblast proliferation assays demonstrated that the collagen gel has an inherent inhibitory effect on osteoblast cell number. CONCLUSIONS: This collagen gel/cytokine delivery system can retain and release bioactive cytokine over a prolonged period. These results will allow for better optimization of future in vitro and in vivo studies directed at improving the treatment of craniosynostosis.