Analysis of the Complications of Mandibular Cortical Bone with/without Particulate Artificial Bone Graft for Alveolar Cleft Reconstruction: A Retrospective Study.

OBJECTIVES: To investigate postoperative complications in patients who underwent alveolar bone graft surgery using mandibular cortical bone (MCB) with/without particulate artificial bone (PAB). DESIGN: Retrospective study. SETTING: Department of Oral and Cranio-Maxillofacial Surgery in the hospital from August 2020 to August 2023. PATIENTS: Patients who underwent alveolar bone graft using MCB were reviewed. They were diagnosed with unilateral or bilateral alveolar cleft, and some of them developed postoperative complications after MCB with/without PAB repair surgery. INTERVENTIONS: No interventions. MAIN OUTCOME MEASURE(S): Complications. RESULTS: Complications occurred in 12 of 149 patients who underwent surgery (8.05%). Among these evaluated patients, 10 had surgical site infection, 8 had mucosal dehiscence, 2 had discharge of resorbable plate debris, and 6 had grafted bone necrosis. Patients with bilateral alveolar clefts were more likely to experience complications (P = 0.033). CONCLUSION: MCB with/without PAB grafting is effective enough for patients to undergo reconstruction of the alveolar process.

[Preparation and Performance Evaluation of Polyacrylamide Hydrogel Coating on the Surface of Silicone Rubber Nasogastric Tube].

Objective: To prepare the hydrogel coating on the surfaces of nasogastric tubes and to evaluate its effect on the insertion of nasogastric tubes in a rabbit model. Methods: The polyacrylamide (PAAm) hydrogel coating was prepared by UV-induced free radical polymerization. The morphology of the PAAm coating and its interfacial bonding with the silicone rubber substrates of nasogastric tubes were observed with scanning electron microscope. The composition of the coating was analyzed by Fourier transform infrared (FTIR) spectrometer and X-ray photoelectron spectrometer (XPS). The water absorption power and stability of the coating were measured by the weighing method. Water contact angle meter was used to measure the wettability of the coating and tribometer was used to determine the friction coefficient of the silicone rubber substrates before and after the modification. The cytotoxicity of the coating on L929 murine fibroblast cell line was explored with CCK-8 assay after 24-h coculturing of the L929 cell line with silicone rubber substrates before and after modification. An animal model of nasogastric tube insertion in New Zealand rabbits was used to evaluate the effect of the lubrication coating by assessing the insertion time and nasal damage. Results: In this study, PAAm hydrogel coating was prepared and constructed on the surface of silicone rubber nasogastric tubes. The coating, with a three-dimensional network structure, showed strong interfacial bonding with silicone rubber substrates. The appearance of amino and carbonyl groups indicated that the PAAm hydrogel coating was grafted on the surfaces of nasogastric tubes. Before the modification, the silicone rubber substrate essentially did not absorb much water, whereas, after the modification, the silicone rubber substrate showed significant improvement of as much as 2.9% in water absorption. After sonication for 90 min, the weight loss rate was only 0.15%. Compared with pristine nasogastric tubes, the water contact angle of the modified nasogastric tubes was reduced from 111.9°±2.2° to 58.9°±1.5° ( t=22.59, P<0.05). In addition, the friction coefficient of silicone rubber nasogastric tubes decreased by 69.3% from 0.378±0.05 to 0.116±0.004 ( t=42.80, P<0.05) after modification. Moreover, there was no significant difference in the cytocompatibility between L929 cells cocultured with pristine nasogastric tube and those cocultured with modified nasogastric tube. The animal experiment of nasogastric tube insertion showed that the insertion time of the modified nasogastric tubes was reduced from (41.6±7.8) s to (12.4±2.9) s ( t=8.509, P<0.05). Laryngoscopy revealed that the PAAm hydrogel coating significantly reduced the mucosal damage caused by the insertion of nasogastric tubes. Conclusion: In this study, PAAm hydrogel coating with strong interfacial bonding was prepared on the surface of silicone rubber nasogastric tubes. The coating has excellent hydrophilic lubrication property and cytocompatibility, effectively shortens the insertion time, and reduces the damage caused by nasogastric tube insertion.

Impact of agitation/activation strategies on the antibiofilm potential of sodium hypochlorite/etidronate mixture in vitro.

BACKGROUND: To investigate the effect of a rotary agitation method or ultrasonically activated irrigation on the antibiofilm effect of a mixture of sodium hypochlorite (NaOCl) and etidronate (1-hydroxyethylidene-1,1-bisphosphonate, HEBP) using a dual-species biofilm model in root canal system. METHODS: Mature dual-species biofilms of Enterococcus faecalis and Streptococcus gordonii were formed in root canals of mandibular premolars. Teeth were randomly allotted (n = 12) to group 1, XP-endo Finisher (XPF); group 2, ultrasonically activated irrigation (UAI); group 3, syringe-and-needle irrigation (SNI). In all groups, canals were instrumented with a rotary instrument (XP-endo Shaper) prior to irrigant agitation/activation. A mixture containing 2.5% NaOCl and 9% HEBP was used throughout the experiment. Bacterial counts from the canal were determined using qPCR before preparation (S1), after preparation (S2), and after final irrigation agitation/activation (S3). Bacterial viability within the dentinal tubules in the coronal, middle and apical root-thirds was quantified using confocal microscopy after Live/Dead staining. The bacterial counts and viability were compared between groups using one-way ANOVA and post-hoc Tukey's tests. Paired t-test was used to compare the bacterial counts within groups. RESULTS: Instrumentation alone could significantly reduce the microbial counts in all the groups (P < 0.0001). Subsequent agitation/activation resulted in significant microbial reduction only in XPF and UAI (P < 0.05), both of which reduced significantly more microbial counts than SNI (P < 0.05). Live/Dead staining revealed that XPF and UAI showed significantly greater percentage of dead bacteria within the dentinal tubules than SNI in the coronal third (P < 0.05); UAI resulted in the significantly highest percentage of dead bacteria in the middle third (P < 0.05); while there was no significant difference between the groups in the apical third (P > 0.05). CONCLUSIONS: When using the sodium hypochlorite/etidronate mixture for irrigation, final irrigant agitation/activation with XP-endo Finisher or ultrasonic can improve disinfection of the main root canal space and the dentinal tubules in the coronal third, while ultrasonically activated irrigation appears to exhibit better disinfection within dentinal tubules in the middle third.

Experiment of Mechanical Properties of a Customized Distractor Based on Three-Dimensional Printing Technology.

ABSTRACT: This study aimed to design and fabricate a customized distractor based on 3D printing technology and compare its mechanical properties with conventional distractor. The investigators designed and implemented a study composed of conventional and customized distractors. The design of customized distractor was based on the specification of conventional mandibular distractors and was fabricated using selective laser melting (SLM) technology. The same type of conventional distractors served as control group. Vickers-hardness test, three-point bending test and welding strength test were carried out for the conventional and customized distractor respectively and data was analyzed with t test using SPSS13.0 software package. The sample was composed of 18 distractors grouped as follows: customized distractor (n = 9) and conventional distractor (n = 9). The customized distractor showed better result than the conventional distractor in mechanical property tests, with statistically significant differences in Vickers-hardness and maximum load (P < 0.05), and no significant differences in yield strength and welding strength (P > 0.05). The results of this study suggest indicated that compared to the conventional distractor, the customized distractor had better mechanical properties and could be used in maxillofacial distraction osteogenesis.

Antioxidant activity and absorption of cyanidin-3-O-glucoside liposomes in GES-1 cells in vitro.

The use of anthocyanins are limited by their chemical properties. Recent evidence suggests Cyanidin-3-O-glucoside (C3 G) liposomes via the ethanol injection method exhibit improved stability. In the current study, the characterization and cell absorption of C3 G liposomes were explored via transmission electron microscopy and flow cytometry. The internalization of the C3 G liposomes across the gastric epithelial cell monolayer (GES-1 cells) were investigated. Results showed that the particle size and encapsulation efficiency were 234 ± 9.35 nm and 75.0% ± 0.001, respectively. The total antioxidant capacity (T-AOC) and malondialdehyde (MDA) content were used to evaluate the antioxidant activity of C3 G liposomes. The C3 G liposomes can obviously increased T-AOC and decreased the MDA content.Collectively, C3 G liposomes protected human GES-1 cells from gastric mucosal injury induced by H2O2 by activating the related antioxidant pathway. Our research could provide a new effective treatment strategy for the absorption of stomach drugs.Abbreviations: C3G: Cyanidin-3-O-glucoside; LP: Liposome; GES-1 cells: Human gastric epithelial cell lines; FBS: Fetal Bovine Serum; PBS: Phosphate-buffered saline; PC: Phosphatidylcholine; CH: Cholesterol; MDA: Malondialdehyde; TEM: Transmission electron microscope; FCM: Flow cytometry; FITC: Fluorescein isothiocyanate; DAPI: 4', 6-diamidino-2phenylidole; FT-IR: Fourier Transform infrared spectroscopy; PFA: Paraformaldehyde.

Nano-Crystalline Sandwich Formed in Polylactic Acid Fibers.

Fibers have traditionally been made through melt or solution processes from macromolecules. Most of these fibers have crystalline domains where the segregation of different crystalline features is extremely difficult due to the statistical nature of the formation and growth of these domains. A fibrous nano-crystalline sandwich is reported where distinctly different crystalline regions are formed in layers along the continuous fiber direction during the spinning process and locked in place. This approach employs side-by-side bicomponent nanofiber electrospinning where the components are the enantiomeric pair of poly(l-lactic acid) and poly(d-lactic acid). The formation of the poly(lactic acid) (PLA) stereo-complexes at the junction interphase of the two components is demonstrated through diffusion, which subsequently crystallize into continuous sandwich domains. The stereo-complex crystalline core in the fiber possesses a melting point 50 °C higher than, and properties substantially different from, the regular PLAs at the fringe areas of the fiber. This nano-crystalline sandwich fiber structure can be scaled to the micrometers in a commercial bicomponent process.

Median Cleft of the Lower Lip and Mandible: Clinical Experience and Surgical Treatment.

Median cleft of lower lip and mandible is a rare congenital craniofacial malformation and has been described as isolated clinical reports. Fewer than 100 cases have been reported in the world literature so far, and the first case was reported by French scholar Monroe in 1819. The authors report a patient with median complete cleft of the lower lip and mandible which we made a special repair surgery for him, surgical effect satisfied with the restoration of appearance and function ideal. Therefore, the appropriate period and method of surgical management are very important.

Combined Counterclockwise Maxillomandibular Advancement and Uvulopalatopharyngoplasty Surgeries for Severe Obstructive Sleep Apnea.

As the most effective surgical technique maxillomandibular advancement (MMA) has been used to treat severe obstructive sleep apnea (OSA) in adults, particularly for those who are intolerant of continuous positive airway pressure. Yet for large-scale advancement, it is faced with esthetic problems with marked skeletal protrusion especially for people with convex facial profile. In this study, the authors performed counterclockwise MMA combined with quantified uvulopalatopharyngoplasty (UPPP) surgeries on Chinese adult patients with severe OSA, in order to initially explore the efficacy of these procedures on Chinese populations and provide evidence for esthetic advantages. As the primary procedure counterclockwise MMA was applied on 10 patients, achieving a forward distance of the mandible and the maxilla for 10.6 and 6.7 mm, respectively, and the occlusion plane rotated counterclockwise of 6.2°. After a follow-up of beyond 12 months, polysomnography results showed the apnea-hypopnea index (AHI) significantly decreased from 64.3 to 11.0 per hour, achieving surgical success of 90%. Upper airway measurements demonstrated that the retropalatal and retrolingual spaces got enlarged greatly, resulting in significant AHI reduction and oxygen saturation elevation. More importantly, cephalometric analysis revealed that SNA and SNB were enlarged but in well control without visual abnormalities. Follow-up results showed large-scale advancement of the maxilla and mandible were stable in treating severe OSA. Quantified UPPP surgeries guaranteed no functional insufficiency in pronouncing and swallowing and played auxiliary role in enlarging the upper airway. Thus, procedures of counterclockwise MMA combined with quantified UPPP surgeries might find more application especially in patients with severe OSA with convex facial profile in future.

Individualized therapy for treating obstructive sleep apnea in pediatric Crouzon syndrome patients.

PURPOSE: Pediatric patients with Crouzon syndrome have great possibilities of suffering from obstructive sleep apnea (OSA), which is mainly due to midfacial hypoplasia and facial deformities. For most patients, a multidisciplinary and sequential treatment plan is necessary to make for Crouzon syndrome often has different phenotypes of different severity in OSA and facial deformities. Typical patients were selected in this paper to illustrate the necessity of individualized therapy for treating OSA. METHODS: In this paper, we have introduced four Crouzon syndrome children of different severity in suffering from OSA and maxillofacial deformities. Detailed information was given including clinical manifestations, radiological findings, and polysomnography detections. Based on the above findings, different but effective treatment options for these children's OSA problems were adopted, either by surgeries including distraction osteogenesis and craniomaxillofacial surgeries with or without tonsillectomy or by noninvasive continuous positive airway pressure (CPAP) therapy. RESULTS: Follow-up studies for more than 1 year showed problems of OSA and nocturnal hypoxia of those four patients were all alleviated greatly, as well as maxillofacial deformities. Combined with pre-operative and post-operative orthodontics, one patient also got optimal results in better facial profile and dental occlusion. CONCLUSION: Thus, based on adequate clinical evaluations and patients' conditions including age, disease severity, and esthetic considerations, individualized therapy should be made and performed carefully to obtain optimized results in treating OSA for pediatric Crouzon syndrome patients.

A novel electrospun nerve conduit enhanced by carbon nanotubes for peripheral nerve regeneration.

For artificial nerve conduits, great improvements have been achieved in mimicking the structures and components of autologous nerves. However, there are still some problems in conduit construction, especially in terms of mechanical properties, biomimetic surface tomography, electrical conductivity and sustained release of neurotrophic factors or cells. In this study, we designed and fabricated a novel electrospun nerve conduit enhanced by multi-walled carbon nanotubes (MWNTs) on the basis of a collagen/poly(ε-caprolactone) (collagen/PCL) fibrous scaffold. Our aim was to provide further knowledge about the mechanical effects and efficacy of MWNTs on nerve conduits as well as the biocompatibility and toxicology of MWNTs when applied in vivo.The results showed that as one component, carboxyl MWNTs could greatly alter the composite scaffold's hydrophilicity, mechanical properties and degradability. The electrospun fibers enhanced by MWNTs could support Schwann cell adhesion and elongation as a substrate in vitro. In vivo animal studies demonstrated that the MWNT-enhanced collagen/PCL conduit could effectively promote nerve regeneration of sciatic nerve defect in rats and prevent muscle atrophy without invoking body rejection or serious chronic inflammation. All of these results showed that this MWNT-enhanced scaffold possesses good biocompatibility and MWNTs might be excellent candidates as engineered nanocarriers for further neurotrophic factor delivery research.

Navigation-assisted mandibular body distraction osteogenesis: a preliminary study in goats.

PURPOSE: The purpose of the present study was to evaluate the accuracy of navigation-assisted distraction osteogenesis of the mandible in a goat model. MATERIALS AND METHODS: Six adult goats were included in the present study. A 3-dimensional (3D) image was reconstructed by performing computed tomography (CT) scans in 0.625-mm slices after placement of 5 maxillary marking screws and intermaxillary fixation with a prefabricated occlusal splint using the TBNavis-CMFS navigation system (Multifunctional Surgical Navigation System, Shanghai, China). Simulation distraction was performed to lengthen a unilateral mandibular body by 10 mm. Image-guided distraction osteogenesis was performed on the goat hemimandibles according to the preoperative planning. 3D skeletal measurements from the simulation were compared with those taken from the CT scans at 3 months postoperatively. RESULTS: Navigation-assisted distraction osteogenesis was successfully performed in all 6 goat hemimandibles. The accuracy of the intraoperative registration was within 1 mm. The hemimandible was lengthened a mean of 10.02 mm (range 9.89 to 10.12). No significant differences were found between the simulation distraction and postoperative 3D measurements (P > .05). CONCLUSIONS: Navigation-assisted distraction osteogenesis of the mandible in the goat model can be performed with high accuracy using the TBNavis-CMFS navigation system.

Application of a novel intraorally customized transport distraction device in the reconstruction of segmental mandibular defect.

PURPOSE: The purpose of this study was to evaluate the clinical result of segmental mandible reconstruction by using a novel intraorally customized trifocal curvilinear distractor. METHODS: A customized curvilinear distractor with self-locking system and bidirection transport assembly was designed on the basis of the mandibular contour of a patient diagnosed with ameloblastoma. Two transport disks, each containing the first molar, were designed for trifocal distraction osteogenesis after partial mandibulectomy intraorally. The latency period is 7 days and distraction rhythm is 1 mm/d. After 6 months of consolidation, the second operation was performed to remove the device. RESULTS: A new bone bridged the mandibular defects through transport distraction successfully. Partial bony nonunion between the transport disks was noted when removing the distractor; rigid internal fixation using a titanium plate and bone graft was carried out to ensure the continuity. Bilateral sagittal split ramus osteotomy was performed to advance the mandible when anterior-posterior jaw bone discrepancy occurred before final denture restoration. CONCLUSIONS: Customized trifocal curvilinear transport distraction osteogenesis can successfully reconstruct segmental mandible defect intraorally, but special consideration should be paid on the dock site bone healing and overcorrection of curvilinear reconstruction in the future.

Treatment of severe skeletal open bite deformity in patients with Möbius syndrome: a report of 3 cases.

PURPOSE: To investigate the treatment of severe skeletal open bite deformities in Möbius syndrome patients. MATERIALS AND METHODS: Three patients aged 17 to 24 years (2 male patients and 1 female patient) with Möbius syndrome were evaluated and treated with preoperative orthodontics, orthognathic surgery, and postoperative orthodontic management. One patient was treated by bilateral V osteotomies of the mandibular body and one patient with bilateral V osteotomies of the mandibular body plus a Le Fort I osteotomy. The third patient had bilateral mandibular ramus sagittal split osteotomies in combination with maxillary osteotomies. Two of the patients had preoperative electromyographic studies on the temporalis and masseter muscles. RESULTS: Postoperative and post-orthodontic stability was good in 2 cases, whereas a 5-mm anterior open bite developed after treatment in 1 case and additional orthodontic management was required to re-establish good occlusion. Potential to redevelop anterior open bites may likely be related to the functional deficiencies of the muscles of mastication and facial paralysis. Two patients who had electromyographic studies to evaluate muscle function showed lower-than-normal function of the temporalis and masseter muscles. Lower lip ptosis remained a significant esthetic issue in 2 of 3 patients. CONCLUSIONS: Patients with Möbius syndrome with severe skeletal open bite deformities can be treated with combined orthodontic and orthognathic surgery; however, there is a tendency for redevelopment of an anterior open bite with the surgical and orthodontic techniques used in these cases.

[Preliminary study on the effect of combined invisible orthodontic and orthognathic treatment in 24 skeletal Class â ¢ patients with facial asymmetry].

PURPOSE: To evaluate the clinical effect of combined orthodontic and orthognathic treatment with invisible aligner technique without brackets in skeletal Class Ⅲ patients with facial asymmetry. METHODS: A total of 24 skeletal Class Ⅲ patients with facial asymmetry treated with combined orthodontic and orthognathic treatment during the past 4 years were reviewed. Patients in the experimental group(n=12) were treated with invisible aligner technique without brackets, while patients in the control group(n=12) were treated with traditional fixed orthodontic technique for pre- and post-operative orthodontic treatment respectively. The cephalometric parameters and satisfaction questionnaire scores of the two groups before and after treatment were compared and analyzed with SPSS 20.0 software package for t test and Wilcoxon rank sum test, respectively. RESULTS: After treatment, the cephalometric parameters of SNA, SNB, ANB, U1-SN and L1-MP values were changed significantly(P＜0.05), but there was no significant difference between the values of experimental group and the control group(P＞0.05). The scores of aesthetics, comfort, portability, masticatory and speech function in the experimental group were significantly higher than those in the control group(P＜0.05). The satisfaction scores of the two groups were both 8.8±0.5(P＞0.05). CONCLUSIONS: Skeletal Class Ⅲ patients with facial asymmetry could obtain good clinical effect by using invisible aligner technique. The patients were satisfied with the aesthetics, comfort and the effect of combined invisible orthodontic and orthognathic treatment.

Physicochemical characteristics of Ganoderma lucidum oligosaccharide and its regulatory effect on intestinal flora in vitro fermentation.

This study explored the structure characteristics of an oligosaccharide from Ganoderma lucidum (GLO) and its regulatory functions on intestinal flora fermentation in vitro. GLO was extracted by ultrasonic-assisted enzymatic hydrolysis, and purified with a dextran gel column. Digestion properties and intestinal flora regulation effects of GLO were investigated by both simulation models. Results showed that GLO was a chain-like homogeneous oligosaccharide, composed of â†’ 6)-ß-d-Glcp-(1→, →4)-α-d-Glcp-(1→, ß-d-Glcp-(1→, α-d-Manp-(1 â†’. Its structure could not be easily degraded by digestion in the mouth, gastric and small intestine. Accordingly, they can be utilized by the intestinal flora in large intestine. By evaluating the gas, short chain fatty acids, pH and flora abundance in vitro fermentation, it indicated that GLO had good regulatory effects on intestinal flora. Accordingly, GLO might be a potential prebiotic applied in functional foods.

Microplastic pollution in the surface seawater in Zhongsha Atoll, South China Sea.

The prevalence of microplastics in the marine environment has attracted extensive attention. So far, no information is known regarding the temporal and spatial variations of microplastics in Zhongsha Atoll. This study, for the first time, comprehensively investigated the occurrence and distribution of microplastics in the surface seawater in Zhongsha Atoll based on two ocean cruises. The abundances of microplastics measured in the surface seawater of Zhongsha Atoll were in the ranges of not detected (ND) to 67 items/m3, and ND to 160 items/m3 in 2019 and 2020, respectively. All microplastics detected in Zhongsha Atoll were fibers, most of which were transparent and less than 2 mm. Polyethylene terephthalate was the dominating composition of microplastics. These results suggested that sewage, surface runoff, atmospheric deposition by neighboring land, and fishing activities may be the primary pollution sources. This study provides critical information on microplastic pollution in Zhongsha Atoll for the first time, calling for more research in the management of marine plastic debris in the future.

Customized bifocal and trifocal transport distraction osteogenesis device for extensive mandibular reconstruction.

PURPOSE: The objective of this study was to report the use of custom-made transport distraction osteogenesis (TPDO) in reconstruction of extensive mandibular defect. METHODS: Two consecutive patients with mandibular defect involving the body and symphysis were described. Presurgical three-dimensional computed tomography and rapid prototype model were used to design the customized distractor. A bifocal TPDO was performed as immediate reconstruction after mandibulectomy. The trifocal TPDO was carried out 2 years after partial mandibulectomy as a secondary procedure. Postoperatively, patients were followed up with clinical examinations and radiographs. The distractors were removed at the end of 8 months of consolidation period. RESULTS: Both distractors were tolerated well. Both patients had achieved soft- and hard-tissue formation. A mild infection and unexpected unilateral coronoid fracture was noted in one of the patients. However, no functional disturbance to the distractor and no adverse impact on the final result were noted. CONCLUSIONS: The use of custom-made TPDO distractor can recreate the mandibular contour in single-stage surgery and avoid the donor-site morbidity. It is a potentially valid method for extensive mandibular defect reconstruction.

Intracranial fixation pin migration: a complication of external Le Fort III distraction osteogenesis in Apert syndrome.

External distraction osteogenesis has long been used in treatment of congenital midface hypoplasia. Distraction osteogenesis is associated with lower relapse rate and less complications compared with standard Le Fort III osteotomy. General complications in using rigid external distraction include localized infection, loosening of pins, and pin displacement. A 24-year-old female patient with Apert syndrome who underwent Le Fort III distraction osteogenesis is reported. Standard Le Fort III osteotomy was performed, and external distractor was placed. After 7-day latency period, the distractor was activated at the rate of 1 mm/d and finished after 20 days. A mild localized infection was recognized at the eighth week of consolidation period, and debridement was carried out at the left side of pin fixation. Obvious displacement of distractor occurred 1 week later while the patient was sleeping, and emergency operation was performed to remove the distractor and depress the left temporal skull bone fracture after clinical evaluation. The patient was asymptomatic clinically, and the advancement of the midface was stable. Le Fort I osteotomy was performed 3 years later to obtain a normal occlusion, and the patient was satisfied with the final outcome. We concluded that an unwanted trauma might cause severe complications such as skull bone fracture secondary to related local infection, and close follow-up and management are necessary for those cases.

The synergistic promotion of osseointegration by nanostructure design and silicon substitution of hydroxyapatite coatings in a diabetic model.

Accumulating evidence indicates much higher failure rates for biomedical titanium implants in diabetic patients. This phenomenon is attributed to impaired osteoblastic function, suppressed angiogenesis capacity, and abnormal osteoclast activation in diabetic patients. Our previous study demonstrated that titanium implants coated with highly crystalline nanostructured hydroxyapatite (nHA) promoted the osteogenic differentiation of bone marrow stromal cells (BMSCs) and bone-implant osseointegration under healthy conditions. Furthermore, recent studies showed that silicon-substituted biomaterials exhibited excellent osteogenesis and angiogenesis performance while repressing osteoclastogenesis. Hence, we proposed that a combination of nanostructural modification and Si substitution might produce synergetic effects to mitigate the impaired osseointegration of bone implants under diabetes mellitus (DM) conditions. To confirm this hypothesis, titanium implants coated with highly crystalline Si-substituted nHA (Si-nHA) were successfully fabricated via atmospheric plasma spraying combined with hydrothermal treatment. An in vitro study demonstrated that compared to the original HA coating, the nHA coating improved osteogenic and angiogenic differentiation and altered the OPG/RANKL ratio of DM-BMSCs. In addition, the Si-nHA coating further enhanced cell proliferation, improved osteogenic and angiogenic differentiation, and repressed osteoclastogenesis in DM-BMSCs. An in vivo study confirmed that the titanium implants coated with nHA or Si-nHA effectively promoted bone formation and bone-implant osseointegration in a diabetic rabbit model, with the Si-nHA coating exhibiting the best stimulatory effect. Collectively, the results suggest that the nanostructured topography and Si substitution act synergistically to ameliorate the poor bone regeneration and osseointegration associated with DM. Thus, the results provide a promising coating method for dental and orthopedic applications under diabetic conditions.

Dentist-related factors influencing the use of vital pulp therapy: a survey among dental practitioners in China.

OBJECTIVE: To evaluate dentist-related factors associated with the use of vital pulp therapy (VPT) for the treatment of pulp exposures in permanent teeth. METHODS: This survey-based study sent an online questionnaire to collect data on the demographics of the respondents, the use of VPT and the choice of materials for VPT, to all members of the Society of Endodontology of Guangdong, China. RESULTS: A total 183 of 380 members responded (48.2%). The majority (89.6%; 164 of 183) had performed direct pulp capping (DPC) while 55.2% (101 of 183) had performed partial pulpotomy (PP) at least once. The most-cited reason for not performing VPT was unfamiliarity with the technique. Mineral trioxide aggregate was the most commonly used material for both DPC (67.1%; 110 of 164) and PP (73.3%; 74 of 101). Endodontists, compared with general practitioners, preferred to perform DPC and chose calcium silicate materials (CSMs) for VPT (odds ratios 5.81 and 8.07, respectively). DPC and CSMs for VPT were also favoured more by respondents who had practised for > 5 years. Senior respondents were more likely to use PP. CONCLUSIONS: Speciality, years of practise and age of dentists influenced the decision making and the choice of materials for VPT. Continuing education is essential to promote the clinical use of VPT.