OBJECTIVETo determine the influence of different surface conditioning methods on bonding strength of low fusing porcelain (La-Porcelain) and titanium.

METHODSThe surface of the samples were sandblasted for 2 min with 80-250 microns Al2O3 or coated for two times with Si-couple agent or conditioned by pre-oxidation. The shear bond strength was examined by push-type shear test with a speed of 0.5 mm/min in a universal testing machine. Scanning electron microscopy (SEM) and electron probe micro-analyzer (EPMA) were employed to explore the relationship between bonding strength and microstructures, as well as the element diffusion at the interface between porcelain coating and titanium when heated at 800 degrees C.

RESULTSBonding strength was not statistically different (P > 0.05) after sandblasting with Al2O3 in particle size ranged from 80 microns to 250 microns. When a Si-couple agent was used, bond of porcelain to titanium was significantly lower (P < 0.05). The shear bond strength of the porcelain to the pre-oxidized titanium surface remained unchanged after heating (P > 0.05). The SEM results revealed integrity of porcelain and titanium.

CONCLUSIONLa-Porcelain showed a small effect of surface coarseness. Sandblasting the titanium surface with 150-180 microns Al2O3 can be recommended as a method for better bonding between La-Porcelain and titanium. The Si-couple agent coating and pre-oxidation of titanium surface is unnecessary.

Aluminum Oxide ; chemistry ; Dental Bonding ; Dental Materials ; Dental Porcelain ; chemistry ; Humans ; Lanthanum ; chemistry ; Materials Testing ; Metal Ceramic Alloys ; chemistry ; Surface Properties ; Tensile Strength ; Titanium ; chemistry

Objective To investigate the effects of new and traditional non-steroidal anti-inflammatory drugs(NSAIDs)on the proliferation,morphology,adhesion,activity and expression of osteoblast related genes of MG-63 osteoblasts by establishing a osteogenic model of implants.Methods MG-63 cells were implanted on sand-blasted,largegrit,acid-etched titanium plates surface(SLA)to establish a model of osseointegration between implant surface and osteoblasts.The experiments included NO-flurbiprofen group,flurbiprofen group and the control group.Cell proliferation was detected by CCK-8 assay,cell morphology was observed by scanning electron microscopy(SEM),cell adhesion was detected by MTT assay,alkaline phosphatase(ALP)activity was detected by chemical method,calcified nodules was observed after Alizarin red staining,and the expression of bone formation related genes ALP,OCN,Runx-2 was detected by RT-qPCR.Results CCK-8 assay showed that statistical difference was observed in cell proliferation among the groups treated with different drug concentrations(P＜0.01).Cell proliferation was higher in the NO-flurbiprofen group and the flurbiprofen group than the control group,and in the NO-flurbiprofen group than the flurbiprofen group(P＜0.01).SEM displayed that the cells from the NO-flurbiprofen group grew to multiple lays first.Cell adhesion results showed that the number of cell adhesion was lower in the NO-flurbiprofen group than the flurbiprofen group and the control group(P＜0.01).ALP activity of drug groups was lower than the control group(P＜0.01).No typical red deeply stained calcified nodules were observed in neither NO-flurbiprofen group nor flurbiprofen group during the observation period.RT-qPCR indicated that the mRNA expression of OCN in the NO-flurbiprofen group and Runx-2 in the flurbiprofen group was higher than those of the control group,while the mRNA level of ALP was lower than that of the control group(P＜0.01).Conclusion Both NO-flurbiprofen and flurbiprofen effectively promote the proliferation of osteoblasts on the surface of titanium plates and the expression of some osteogenic related genes.The promotion effect of NO-flurbiprofen is more significant.

OBJECTIVETo study the microstructure of the Ag-nHA-nTiO2/PA66 membrane and investigate its biocompatibility.

METHODSThe microstructure of Ag-nHA-nTiO2PA66 membrane and e-polytetra fluoroethylene (e-PTFE) membrane were observed by light microscope and scanning electron microscope(SEM). MG63 osteoblast-like cells were cultured on the two kinds of membrane and blank group. The cell proliferation was checked by methyl thiazolyl tetrazolium (MTT) method and alkaline phosphatase (ALP) activity was detected by enzyme linked immunosorbent assay (ELISA). The adhesion and proliferation of the cells on the two kinds of membrane was observed by SEM.

RESULTSThe Ag-nHA-nTiO2/PA66 membrane was composed of the obverse face and the opposite face. The obverse face was porous and the opposite face was smooth. Microstructures of the obverse and the opposite face of the e-PTFE membrane were same. The e-PTFE membrane showed many tiny lined cracks in elliptic structure. MTT assay and ALP measurement showed that there were no significant difference between each of the two membrane groups and the blank (P > 0.05). The adhesion and proliferation of cells on the Ag-nHA-nTiO2/PA66 membrane were better than the e-PTFE membrane.

CONCLUSIONAg-nHA-nTiO2/PA66 membrane has no negative effects on the growth of osteoblast-like cells. Ag-nHA-nTiO/PA66 membrane is biocompatible and its microstructure is appropriate as a guided bone regeneration materials.

Anti-Bacterial Agents ; Bone Regeneration ; Cell Proliferation ; Durapatite ; Nanocomposites ; Nylons ; Osteoblasts

Objective: To investigate the application effect of bovine pericardium in horizontal bone augmentation surgery in the aesthetic area and to assess its clinical feasibility in guided bone regeneration (GBR). Methods: This study was approved by the Ethics Committee. A total of 29 patients with anterior tooth loss accompanied by labial bone defects were selected, and horizontal bone augmentation was performed using a bovine pericardium membrane combined with particulate or block bone grafts. Centered on the virtual implant in the preoperative design, labial bone thickness at the implant neck and 1-5 mm below it was measured at different time points: preoperatively (T0), immediately postoperatively (T1), and 6 months postoperatively (T2). The results were used to assess bone regeneration outcomes. Additionally, the visual analog scales (VASs) of postoperative pain and swelling were recorded, and whether any complications such as infection or wound dehiscence occurred were monitored. Results: Immediately after surgery, labial bone thickness of all implants significantly increased, with an average increase more than 3 mm. Six months after surgery, the bone augmentation was well maintained. Specifically, labial bone thickness 3-5 mm below the shoulder of the implant was greater than 3 mm. The VAS scores showed that postoperative pain and swelling peaked on the third day and then gradually decreased, with good recovery 10 days after surgery. No complications such as infection or wound dehiscence occurred during the follow-up period. Conclusion Bovine pericardium shows good bone augmentation effect and biocompatibility in horizontal bone augmentation in the anterior aesthetic area, and it is suitable for various horizontal bone augmentation surgeries in the aesthetic area.

MXenese is a type of two-dimensional inorganic compound in materials science that is composed of transi-tion metal carbides,nitrides,or carbonitrides with several atomic layer thicknesses.Owing to the presence of hydroxyl groups or terminal oxygen groups on the surface of MXene materials,they exhibit metallic conductivity similar to that of transition metal carbides.Owing to their excellent optical,mechanical,electrothermal,and biocompatible properties,emerging 2D MXenes are widely used in biomedical fields such as tissue engineering,antimicrobial drugs,photothermal therapy,drug/gene delivery,sensing,and regenerative medicine.In this paper,we review the methods for synthesizing and modifying MXene-based composites,their research and application in stomatology,and their development prospects and challenges in the clinical application of tissue engineering.The biocompatibility and osteogenic properties of MX-ene and its nanocomposites have the potential to promote cell proliferation and bone regeneration.The anti-bacterial ad-hesion and biofilm formation properties can be applied to implant coating and prevent caries.The excellent photother-mal,conductive,and mechanical sensitivity of this agent make it suitable for drug delivery,bio-photothermal therapy,immune signal sensing,and gene detection.On this basis,MXene has recently achieved outstanding results in the fields of stomatology,including bone tissue engineering,antimicrobial,drug delivery,physical and mechanical enhancement of dental biomaterials,oral cancer treatment,and periodontal disease monitoring.However,research on the prevention and treatment of refractory oral diseases has not yet been reported.At present,the properties and surface modification of MXene-based nanomaterials are relatively well understood.Future studies should focus on the dose-dependent biosafety,cellular and molecular mechanisms,and signaling pathways of MXene to fully exploit its unique advantages in oral clini-cal and tissue engineering fields.

Odontogenic maxillary sinusitis(OMS)is a subtype of maxillary sinusitis(MS).It is actually inflammation of the maxillary sinus that secondary to adjacent infectious maxillary dental lesion.Due to the lack of unique clinical features,OMS is difficult to distinguish from other types of rhinosinusitis.Besides,the characteristic infectious pathogeny of OMS makes it is resistant to conventional therapies of rhinosinusitis.Its current diagnosis and treatment are thus facing great difficulties.The multi-disciplinary cooperation between otolaryngologists and dentists is absolutely urgent to settle these questions and to acquire standardized diagnostic and treatment regimen for OMS.However,this disease has actually received little attention and has been underrepresented by relatively low publication volume and quality.Based on systematically reviewed literature and practical experiences of expert members,our consensus focuses on characteristics,symptoms,classification and diagnosis of OMS,and further put forward multi-disciplinary treatment decisions for OMS,as well as the common treatment complications and relative managements.This consensus aims to increase attention to OMS,and optimize the clinical diagnosis and decision-making of OMS,which finally provides evidence-based options for OMS clinical management.

Objective : To investigate the effect of immediate and delayed implant placement on dimensional changes in hard and soft tissues as well as esthetic outcomes. Methods : A total of 40 maxillary single anterior teeth with a dehiscence defect on the labial bone (≤4 mm) were categorized into two groups according to the timing of implant placement: immediate implant placement (n = 20) or delayed implant placement (n = 20). Guided bone regeneration (GBR) was conducted at the sites using a flap approach, and the implants were given immediate provisionalization. Implant survival rates, dimensional changes in hard and soft tissues during the six- and twelve-month follow-ups, and pink esthetic scores (PESs) were measured. Results : The implant survival rates in both groups were 100%, and no complications occurred during the follow-up time. There was no significant difference between the two groups at the measurement sites in the dimensional change of hard and soft tissues during the six- and twelve-month follow-ups. The largest resorption was observed at the implant neck, with a loss of (1.29 ± 0.71) mm in the immediate implant placement group and (1.43 ± 0.19) mm in the delayed implant placement group. The mean PES scores were (10.95 ± 1.51) for the immediate implant placement group and (11.05 ± 1.23) for the delayed implant placement group. Conclusion Immediate implantation or delayed implantation combined with GBR and immediate provisionalization might both be a prospective treatment strategy for a maxillary single anterior tooth with a dehiscence defect on the labial bone.

Objective: To study the postoperative soft and hard tissue changes and aesthetic effect of immediate implantation and provisionalization (IIPP) combined with guided bone regeneration (GBR) for a single anterior maxillary tooth with a thin facial bone phenotype. Methods : A total of 34 patients with thin facial bone (<1 mm) were categorized into two groups: a flapped GBR group and a flapless group. Tooth extraction and IIPP were conducted at the sites in both groups. Implant survival rates, dimensional changes in soft and hard tissues during the six- and twelve-month follow-ups, the pink esthetic score (PES) and patient satisfaction scores at the twelve-month follow-up were measured. Results : The implant survival rates were 100% in both groups, and no complications occurred during the 12 months after surgery. The facial bone thickness remained over 2 mm on all measured sides, and the height of the facial bone crest remained at 1.39 mm at the 12-month follow-up in the flapped GBR group, while the facial bone thickness remained less than 2 mm on all measured sides, and the height of the facial bone crest remained at 1.03 mm at the 12-month follow-up in the flapless group. The absorption of facial bone at all measured sides in the flapped GBR group was greater than that in the flapless group (P<0.05). There was no significant difference between the two groups in the dimensional changes of labial soft tissues during the six- and twelve-month follow-ups (P>0.05). The mean PES scores were 10.29 ± 2.34 for the flap GBR group and 10.12±1.78 for the flapless group (P = 0.807). The mean patient satisfaction scores were 8.65 ± 1.27 in the flapped GBR group and 8.76 ± 1.25 in the flapless group, and the patients in both of the groups were satisfied with the esthetic outcomes (P = 0.787). Conclusion IIPP combined with GBR might be a prospective treatment strategy for a single anterior maxillary tooth with a thin facial bone phenotype, but the esthetic risks should never be ignored.