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Background Heterotopic ossification (HO) is one of the serious complications leading to the failure of alloplastic temporomandibular joint replacement (TJR). However, there was few research on its exact incidence and occurrence. Severe HO might result in pain and limited mouth opening after surgery. Therefore, it is necessary to clarify its clinical and imaging manifestations. The purpose of this study was to study the occurrence and classify HO after the alloplastic TJR. Method Patients who underwent standard TJR (Zimmer Biomet stock prostheses or Chinese stock prostheses) with fat graft and at least 1-year-follow-up were included. HO was classified into 4 types according to postoperative computed tomography (CT) scans. Type and occurrence in different TMJ disease were compared. Joint space within 1 week after operation was measured and compared between HO and non-HO TJRs. Maximum incisal opening (MIO), pain, and quality of life (QoL) were recorded and their relevance with HO was analyzed statistically. Result 81cases with 101 joints were included in the study. The mean follow-up time was 22.9 months (12 ~ 56 months). Among the 48 joints, 27 (56.3%) were type I (bone islands); 16 (33.3%) were type II (bone spurs from the mandibular ramus); 3 (6.3%) were type III (bone spurs from the fossa); and 2 (4.2%) were type IV (bone spurs from both the mandibular ramus and fossa). In HO patients, joint space in type IV was smaller than the other 3 types. Pain scores in HO were significantly greater than non-HO patients before and after operations (p Conclusion HO after alloplastic TJR with fat graft was not severe except for type IV, which was easy to cause ankylosis. Preserving sufficient TJR space was important for ankylosis prevention.

Background Heterotopic ossification (HO) is one of the serious complications leading to the failure of alloplastic temporomandibular joint replacement (TJR). However, there was few research on its exact incidence and occurrence. Severe HO might result in pain and limited mouth opening after surgery. Therefore, it is necessary to clarify its clinical and imaging manifestations. The purpose of this study was to study the occurrence and classify HO after the alloplastic TJR. Method Patients who underwent standard TJR with fat graft and at least 1-year-follow-up were included. HO was classified into 4 types according to postoperative computed tomography (CT) scans. Type and occurrence in different TMJ disease were compared. Joint space was measured between HO and non-HO TJRs. Maximum mouth opening (MIO), pain, and quality of life (QoL) were recorded and their relevance with HO was analyzed statistically. Result 81cases with 101 joints were included in the study. The mean follow-up time was 22.9 months. 48 joints (47.5%) had varying degrees of HO. Among them, 27 (56.3%) were type I (bone islands); 16 (33.3%) were type II (bone spurs from the mandibular ramus); 3 (6.3%) were type III (bone spurs from the fossa); and 2 (4.2%) were type IV (bone spurs from both the mandibular ramus and fossa). Joint space in type IV HO was significantly smaller than the other 3 types (9.9 ± 1.1mm, p = 0.01). Pain scores in HO were significantly greater than non-HO patients before and after operations (p

Background Disc repositioning by Mitek anchors for anterior disc displacement (ADD) combined with orthognathic surgery gained more stable results than when disc repositioning was not performed. But for hypoplastic condyles, the implantation of Mitek anchors may cause condylar resorption. A new disc repositioning technique that sutures the disc to the posterior articular capsule through open incision avoids the implantation of the metal equipment, but the stability when combined with orthognathic surgery is unknown. The purpose of this study was to evaluate the stability of temporomandibular joint (TMJ) disc repositioning by open suturing in patients with hypoplastic condyles when combined with orthographic surgery. Methods Patients with ADD and jaw deformity from 2017 to 2021 were included. Disc repositioning by either open suturing or mini-screw anchor were performed simultaneously with orthognathic surgery. MRI and CT images before and after operation and at least 6 months follow-ups were taken to evaluate and compare the TMJ disc and jaw stability. ProPlan CMF 1.4 software was used to measure the position of the jaw, condyle and its surface bone changes. Results Seventeen patients with 20 hypoplastic condyles were included in the study. Among them, 12 joints had disc repositioning by open suturing and 8 by mini-screw anchor. After an average follow-up of 18.1 months, both the TMJ disc and jaw position were stable in the 2 groups except 2 discs moved anteriorly in each group. The overall condylar bone resorption was 8.3% in the open suturing group and 12.5% in the mini-screw anchor group. Conclusions Disc repositioning by open suturing can achieve both TMJ and jaw stability for hypoplastic condyles when combined with orthognathic surgery.

To evaluate the effect of different temporomandibular joint (TMJ) disc repositioning surgeries for the treatment of anterior disc displacement (ADD) in juvenile patients with skeletal Class II malocclusion.Patients (20 years, cervical vertebral maturation stage, IV-V) who had bilateral TMJ ADD with skeletal Class II malocclusion were treated by disc repositioning surgery (mini-screw anchor, [MsA]; or opening suturing, [OSu]). Magnetic resonance imaging (MRI) and lateral cephalometric films before and more than 12 months after surgery were collected from all patients. Changes of SNA, SNB, ANB, incisor overjet, pogonion position (pg'-G'), and condylar height were measured before and after surgery in different disc reposition surgeries and compared by statistical analysis.Eighty-four patients with an average age of 16.44 years and follow-up time of 14.60 months (12 to 33 months) were included in the study. Among them, 16 patients had a mean follow-up of 14.8 months without treatment before disc repositioning. Their condylar height was significantly decreased (P = .004) by MRI measurement. Six patients who had cephalometric films showed significantly decreased SNB (P = .042) and increased overjet (P = .037). After disc repositioning by either OSu (54 cases) or MsA (30 cases), condylar height, SNB were significantly increased and overjet, Pg'-G', ANB were decreased in both groups (P0.001). There was more new bone height in OSu than MsA (P = .004), but no significant differences in SNB, ANB, overjet and Pg'-G' between the 2 groups (P.05). The new bone height was significantly correlated with the surgical method (P = .029), age (P = .015), SNB (P = .008), overjet (P = .048) and pg'-G' (P = .001).Both types of disc repositioning method can effectively promote condylar regeneration and improve skeletal Class II malocclusion in adolescents with ADD. Disc repositioning by OSu obtained more new bone height than MsA.

Purpose The aim of the study was to compare bone adaptation after design modification in Biomet stock prostheses. Materials and methods Computed tomography (CT) data of the patients treated with a Biomet TMJ replacement from 2010 to 2016 were recruited. Fossa prosthesis with a bulge and 4 types of condyle-ramus angle prostheses were virtually designed and implanted by computer-assisted simulation. The amount of bone trimming including fossa, mandibular ramus and bone graft were measured by ProPlan CMF 1.4 software. The differences between the original and modified prostheses were compared by SPSS 17.0 software for statistical analysis. Results There were 54 patients’ CT data included in the study. The amount of fossa bone trimming was 150.20 mm3 in the modified prosthesis and 281.82 mm3 in the original one. The amount of ramus bone trimming was 103.86 mm3 in the modified prosthesis and 229.45 mm3 in the original one. The amount of fossa bone grafting was 95.88 mm3 in the modified prosthesis and 263.03 mm3 in the original one. There were significant differences between them (p = 0.000). Conclusions The modified Biomet prostheses design requires less bone trimming and grafting for implantation.

In this study, in order to increase the flame retardancy of polyacrylonitrile fiber fabric, an organic–inorganic hybrid silane coating doped with polyphosphoric acid was prepared using tetraethoxysilane as the precursor by sol–gel technique. Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy and scanning electron microscope confirm the successful silicon and phosphorus-doped silicon coating on polyacrylonitrile fabric. Obviously, the char residue values at 800 °C of the silica-coated and phosphorus-doped silica coated polyacrylonitrile fabric samples were observed to increase 17.93 and 25.92%, respectively than that of the control sample. The peak and total heat releases of the phosphorus-doped silica coated polyacrylonitrile fabric significantly reduced to only 44.9 and 42.1% of that of polyacrylonitrile fabric, respectively. Besides, both the peak values of smoke production rate and total smoke production are remarkably reduced. The results show that the coated layer can effectively improve the thermal stability, and strengthen the ability to form a thermally stable and condensed barrier for heat and mass transfer. Furthermore, the phosphorus-doped silica-coated polyacrylonitrile fabric provided a novel and efficient method to prepare flame retardant polyacrylonitrile fabric with attractive features. In this article, an efficient and facile method was successfully demonstrated to prepare novel fire retardant PAN fabric. The organic–inorganic hybrid silane coating doped with polyphosphoric acid (PPA) can effectively retard the thermal degradation of PAN fabric, enhane the char-forming ability and can produce a stable and compact shielding layer. The phosphorus-doped silica-coated PAN fabric has lower values of pHRR, THR, pSPR, TSP, aMLR and FIGRA, compared to the control PAN fabric.

The polypropylene melt-blown nonwoven membrane (PPM) is widely used in healthcare; however, the highly hydrophobic nature of the PPM readily adsorbs proteins and polysaccharides, which are conducive to bacteria being retained in the network, resulting in biofouling. Therefore, to improve the hydrophilic and antimicrobial properties of PPM, acrylic acid (AA) was first graft-polymerized on PPM (PPM- g-AA) by ultraviolet (UV)-induced photo-grafting polymerization. Chitosan (CS) was then covalently grafted onto PPM- g-AA to obtain the bigrafted PPM (PPM- g-AA- g-CS). Finally, silver (Ag) nanoparticles were immobilized onto PPM- g-AA- g-CS to create the hydrophilic and antibacterial PPM. The surface chemical composition and morphology of the samples were characterized by Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and scanning electron microscopy. The hydrophilic and antimicrobial properties of the modified PPM were assessed using static water contact angle measurements, wetting time, and bacteria colony-counting assays. The results show that PPM- g-AA- g-CS with immobilized Ag nanoparticles has excellent antibacterial and hydrophilic properties.

A kind of viscose fiber fabric with permanent flame retardancy has been prepared by grafting polymerization of phosphorus and nitrogen-containing monomer, i.e. 2,2-dimethyl-1,3-propanediol acrylamide methoxyl phosphate (DPAMP) onto viscose fiber fabric (VF-g-DPAMP). The effects of the initiator concentration, DPAMP concentration, temperature, pH and time on grafting polymerization were studied, and the structure of VF-g-DPAMP was determined with Fourier transform infrared spectrometry, X-ray photoelectron spectroscopy. The surface morphology of viscose fiber fabric and VF-g-DPAMP were studied by scanning electron microscope. The thermal property and fire retardant performance of VF-g-DPAMP were assessed by thermogravimetric analysis, limited oxygen index measurements and cone calorimeter test, respectively. The results show that DPAMP has been successfully grafted onto viscose fiber fabric, and VF-g-DPAMP has good char-forming ability and better fire retardancy. The pkHRR and THR of the grafted fabric decrease from 150 to 98 kW/m2 and 5.70 to 1.73 MJ/m2, respectively.

To evaluate the preliminary clinical outcomes on the Chinese standard temporomandibular joint (TMJ) prostheses.Patients who underwent Zimmer Biomet and Chinese standard prostheses by one surgeon between January 1st 2016 and June 30th 2017 were included in the study. Maximum incisal opening (MIO), pain, diet, and joint function were measured; CT scans were taken before and after the operation and during at least a 12-months follow-up for evaluation.Thirty-five patients including 12 with Chinese standard prostheses and 23 with Biomet stock prostheses participated in the study. After an average of 14.3 months follow-up, both types of prostheses could significantly improve MIO, diet, and joint function, and relieve pain (p 0.05). There were no significant differences in diet, pain level and joint function either before or after the operation between the two types of prostheses, whereas after the operation, the MIO with Chinese standard prostheses was significantly larger than with the Biomet stock prostheses (p 0.05). However, there was no significant difference before operation (p 0.05). A computed tomography (CT) scan showed that no prostheses dislocated or broke, no screws loosened, and ectopic bone formation appeared around the alloplastic condyle.Chinese standard TMJ prostheses are effective and stable in clinical application. They can significantly improve mouth opening, diet, and joint function and relieve pain.

Purpose The aim of this study was to evaluate the clinical and radiologic results of Zimmer Biomet stock prostheses (Jacksonville, FL) in temporomandibular joint replacement after surgical modifications during at least 1 year of follow-up. Patients and Methods We recruited patients treated by Zimmer Biomet stock prostheses after technical modifications, including digital templates, autogenous ipsilateral bone grafting from the mandible to the fossa, salvaging of the disc remnant and suturing it to the medial aspect of the prosthesis, and fat grafts from a retromandibular incision, between 2010 and 2016. Clinical examination findings including maximal incisal opening; visual analog scale scores for pain, diet, and mandibular movement; and quality of life were compared before the operation and at least 1 year postoperatively. The status of the fossa bone graft was evaluated by computed tomography examination. Results The study comprised 38 joints in 33 patients with diagnoses including osteoarthritis, ankylosis, and neoplasm. Compared with before the operation, maximal incisal opening and visual analog scale scores for diet, function, and pain level, as well as the quality-of-life survey score, were considerably improved during the last follow-up. Computed tomography scans showed all bone grafts were completely healed within the fossa 1 year after surgery. There was no ectopic bone formation, screw loosening, or component displacement or breakage. Conclusions Our surgical modifications of Zimmer Biomet stock prostheses showed good results for at least 1 year of follow-up.

Objective The aim of this study was to evaluate the long-term results after costochondral grafting (CCG) in growing children with temporomandibular joint ankylosis and jaw deformity by 3-dimensional computed tomography (CT) measurement. Study Design Patients with unilateral TMJ ankylosis and jaw deformity treated by CCG from 2010 to 2014 were evaluated. Their CT data within 1 week after operation and after at least 2 years of follow-up were analyzed using ProPlan CMF 1.4 software. Maximal incisal opening (MIO), condyle–ramus heights, chin deviation, and growth of CCG were measured and compared before and after the operation and at the last follow-up. SPSS 17.0 software was used for statistical analysis. Results Seven patients were included in the study. The mean follow-up period was 46.4 months. Five of 7 patients treated with this protocol experienced good mouth opening and symmetric mandibular growth. One patient achieved good mouth opening but not symmetric growth, and 1 patient experienced ankylosis again. Conclusions CCG can be a reliable method to treat temporomandibular joint ankylosis with jaw deformity in growing children. Continued growth occurs in the children, but long-term outcomes require further investigation.