Chinese Journal of Tissue Engineering Research / Zhongguo zu zhi gong cheng yan jiu. 12/18/2021, Vol. 25 Issue 35, p5604-5609. 6p.
MANDIBLE, BONE growth, SURGICAL dressings, DISEASE relapse, MANDIBULAR prosthesis, COMPRESSION bandages, DENTAL implants, and TUMOR surgery
BACKGROUND: In recent years, distraction osteogenesis has become an important alternative option to the reconstruction of mandibular segmental bone defects. OBJECTIVE: To explore the clinical feasibility and efficiency of transport distraction osteogenesis for reconstruction of segmental mandibular bone defect and later dental implantation. METHODS: Six patients with ameloblastoma or keratocystic odontogenic tumor were included in this study. Computed tomography and panoramic film were performed for preoperative evaluation and surgical planning. Transport distraction osteogenesis was used to reconstruct the defect after tumor resection. The fixation period after distraction varied from 16 to 25 weeks, depending on the degree of ossification in the distraction space after operation. The second operation was performed to remove the traction device and restore the gap between the delivery disc and the residual bone defect with bone graft and rigid internal fixation. Finally, the occlusal relationship was restored by dental implantation on the new bone in the distraction space. RESULTS AND CONCLUSION: All patients successfully completed the whole treatment period without traction failure or tumor recurrence. The stretch length ranged from 45 to 57 mm. Satisfactory new bone formation and high calcification in the distraction space were confirmed by imaging examination and intraoperative observation. Of the six patients, one developed infection, and the symptoms were controlled by surgical dressing change; two had salivary leakage, and were cured by pressure bandaging and atropine. All patients eventually achieved satisfactory facial appearance and occlusal function. The findings of this study indicate that transport distraction osteogenesis can be used to reconstruct segmental mandibular bone defect and further used in clinical dental implant treatment, and moreover, the therapeutic effect is satisfactory. [ABSTRACT FROM AUTHOR]
Chinese Journal of Tissue Engineering Research / Zhongguo zu zhi gong cheng yan jiu. 8/8/2021, Vol. 25 Issue 22, p3558-3564. 7p.
DRUG coatings, DENTAL implants, OSSEOINTEGRATION, SURFACE coatings, CONTROLLED release drugs, PHARMACOLOGY, and DRUG carriers
BACKGROUND: Drug coating on implant surface can effectively enhance dental implant osseointegration and reduce the difficulty of implant restoration. OBJECTIVE: To review the effects of different drug coating on implant surface on osseointegration. METHODS: The first author searched PubMed, VIP, Wanfang and CNKI databases for relevant articles published from January 1986 to July 2020. The search terms were “implant, osseointegration, surface coatings, systemic drugs, carrier” in English and Chinese, respectively. Finally, 67 articles were included in result analysis after screening and summarizing. RESULTS AND CONCLUSION: Drug coating on the surface of dental implants can promote the local release of bone binding of dental implants through the carrier, and significantly enhance osseointegration intensity and success rate and maximum load of implant, especially reducing the risk of implantation failures rates by osteoporosis. However, we need to solve some problems before this new coating technical is applied to the clinic: the reliability of the combination of carrier materials and drugs, drug release rate and release amount difficult to control, high initial sustained release concentration of local target tissue and difficult to maintain long-term stability and biocompatibility after implantation. Therefore, in the face of the complex oral microenvironment, as well as the influence of many factors of the patient’s physical condition, it needs to be further verified in clinical trials in the later stage, so as to play a positive role of drug coating technology in the field of oral implantation. [ABSTRACT FROM AUTHOR]
BACKGROUND: Polyetherketoneketone has excellent biocompatibility and is widely used in biomedical fields such as spine, joint and oral and maxillofacial surgery. OBJECTIVE: To summarize the synthesis of polyetherketoneketone and its research progress in medical applications. METHODS: PubMed, Web of Science and CNKI databases were searched for the articles concerning about the synthesis and development of polyetherketoneketone and their applications in the field of biomedicine with the search terms of “polyetherketoneketone, synthesis, scaffold material, implant, tissue engineering, biocompatibility” in English and Chinese, respectively. After initial screening of all articles according to inclusion and exclusion criteria, articles with higher relevance were included for review. RESULTS AND CONCLUSION: In recent years, with the rise of the combination of medical and engineering, polyetherketoneketone and its composites have been gradually applied to the fields of orthopedics, oral and maxillofacial surgery. In orthopedics, polyetherketoneketone and its compounds modified with different physical and chemical properties can not only maintain the elastic modulus similar to human bones, increase the hardness, but also improve its biocompatibility, increase its antibacterial properties, and promote osseointegration. In oral and maxillofacial surgery, it can be used as a dental implant matrix, frame, and snap ring for removable partial dentures. Polyetherketoneketone can not only maintain good aesthetic advantages, but also has good fatigue resistance and retention, which is comparable to the oral cavity. The bonding system can ensure sufficient bonding ability, so polyetherketoneketone has great potential as a dental restoration material. In-depth research on the modification of polyetherketoneketone and its compound is still a hot topic. Through continuous improvement of the performance of the material, more in vivo and in vitro experiments have been carried out to confirm the superiority of polyetherketoneketone as an implant material for orthopedics and oral and maxillofacial surgery to make clinical transformation and it will have very good application prospects. [ABSTRACT FROM AUTHOR]
Geranmayeh, Sasan, Şahiner, Eren, Aşlar, Engin, Polymeris, George S., and Meriç, Niyazi
Nuclear Instruments & Methods in Physics Research Section B. Jul2021, Vol. 499, p89-99. 11p.
OPTICALLY stimulated luminescence, QUARTZ, LUMINESCENCE, RADIATION dosimetry, ARTIFICIAL implants, DENTAL implants, and ELECTRIC fuses
• Porcelain-based materials were investigated using stimulated luminescence methods. • Luminescence dosimetric properties were examined. • The lowest detectable dose limits (LDDL) of the porcelain-based materials were studied. • Luminescence kinetic parameters of both TL and OSL signals were determined. In the present study, different porcelain-based materials including a sugar bowl, an ashtray, a porcelain breaker, an artificial dental implant, an electric fuse and the seal of a porcelain moneybox were investigated via thermally (TL) and optically stimulated luminescence (OSL). For this purpose, luminescence dosimetric properties such as TL and OSL curve shapes, reproducibility, bleachability, along with dose response features such as linearity and lowest detectable dose limits (LDDL) of these materials were compared. A feature that is sample-dependent deals with both quartz and mullite content of each porcelain paste, as it was indicated by XRD analysis. Three dominant peaks in TL glow curves were ubiquitously observed, and OSL decay curves formed in two components (C 1 and C 2) for all samples. It was determined that the LDDL for only two TL peaks (P1 and P2) seem acceptable for accidental retrospective dosimetry applications (0.9–2.2 Gy). On the other hand, the LDDL values obtained according to OSL analysis yielded more promising results in terms of accidental retrospective dosimetry applications as 0.3–0.4 Gy and 0.75–1.35 Gy for C 1 and C 2 components, respectively. TL peaks P1 and P2 indicate the majority of prevalent, if not universal, properties of stimulated luminescence. This latter universality could support an argument towards identification of these two TL peaks directly correlated to quartz mineral. On the other hand, TL P3 could be attributed to a contribution of more than one mineral, such as quartz, kaolinite and mullite, due to the lack of prevalence over all stimulated luminescence features. [ABSTRACT FROM AUTHOR]
MAXILLA surgery, MAXILLOFACIAL surgery, DENTAL implants, SURGICAL flaps, SOCIAL support, PLASTIC surgery, and FIBULA
Objectives: To present a method to reconstruct the midface using the fibula as both a microvascular free flap and as a free cortex graft. Methods: 22-year-old male presented with bilateral maxillary odonotogenic myxoma. Bilateral total maxillectomy defects were reconstructed using an osteocutaneous fibula free flap. The nasomaxillary buttresses were augmented using free cortex grafts to provide additional soft tissue projection and lateral nasal support. Results: The patient received dental implants at 10 months postoperatively and resumed a normal diet. His midface height, nasal and maxillary projection were adequate. At 36 months post-treatment he has no evidence of disease recurrence or resorption of the free bone grafts. Conclusion: The fibula free flap can be used to provide additional support to a patient's reconstruction by means of free cortex grafts. The patient has had successful restoration of pyriform aperture, nasal projection, mastication, and dental restoration using a single donor site. [ABSTRACT FROM AUTHOR]
• Bisphosphonates enhanced metalloproteinases synthesis and activity by fibroblasts. • Zoledronic acid induces higher synthesis and activity of metalloproteinases. • Increased metalloproteinases by bisphosphonates may impair peri-implant healing. This study aimed to assess the influence of the bisphosphonates zoledronic acid and sodium alendronate on MMP-2 and MMP-9 synthesis and activity by gingival fibroblasts seeded onto titanium substrate. Titanium discs were placed in 24-well cell culture plates and gingival fibroblasts were seeded (1 × 105 cells/discs) on them using Dulbecco's Modified Eagle's Medium (DMEM) + 10 % fetal bovine serum (FBS) for 24 h. After this period, a fresh serum-free DMEM containing zoledronic acid or sodium alendronate at 0.5 μM, 1 μM or 5 μM was applied on the cells for an additional of 24 h. Serum-free DMEM and tumor necrosis factor alpha (TNF-α) were used as negative and positive controls, respectively. MMP-2 and MMP-9 synthesis and activity were determined by ELISA (Enzyme-Linked Immunosorbent Assay) and conventional/in situ zymography. Quantitative data were analyzed by one-way ANOVA and Tukey's tests (α = 0.05). The in situ zymography data were qualitatively described. Despite both bisphosphonates increased the MMPs synthesis, this effect was significant higher in zoledronic acid groups. MMPs activity resembled by gelatinolytic activity was also enhanced by sodium alendronate and zoledronic acid in a similar pattern. Zoledronic acid and sodium alendronate increased in a dose-dependent manner MMP-2 and MMP-9 synthesis by gingival fibroblasts seeded on titanium. MMP-2 activity was up-regulated by zoledronic acid treatment. [ABSTRACT FROM AUTHOR]
PHYTIC acid, TITANIUM, DENTAL implants, ATOMIC force microscopy, X-ray photoelectron spectroscopy, BONE mechanics, and MAGNESIUM
[Display omitted] • The fabrication of Phytic acid-magnesium multilayer on titanium was simple and cost-effective. • Phytic acid-magnesium multilayer bonded on titanium covalently with good stability. • Phytic acid-magnesium multilayer showed balanced antibacterial and osteogenic properties. In order to improve early osseointegration and long-term survival rate of implants, a multifunctional titanium surface that promotes osteogenesis and antibacterial properties is expected. Incorporation of bioactive trace elements such as magnesium ions was proved a promising method to improve osseointegration of titanium. Phytic acid has strong chelating ability with multivalent cations, which has been used in surface modification. Moreover, phytic acid was proved antibacterial potential. Herein, to improve the osteogenic and antibacterial properties, a phytic acid-magnesium (PA-Mg) layer was introduced on titanium using phytic acid as a cross-linker molecule. No obvious changes of the surface characterization were observed by scanning electron microscopy and atomic force microscopy. X-ray photoelectron spectroscopy confirmed that the PA-Mg layer covalently bond to the Ti surface, and the thickness of the PA-Mg layer was about 150 nm. Besides, improved hydrophilic and more protein adsorption were observed on Ti-PA-Mg. Notably, a relatively controlled magnesium release was also observed on Ti-PA-Mg. Human bone mesenchymal stem cells showed better adhesion, proliferation, and osteogenic differentiation on Ti-PA-Mg samples, indicating improved biocompatibility and osteoinductivity. Moreover, Ti-PA-Mg had better antibacterial properties against porphyromonas gingivalis than Ti. Overall, the PA-Mg layer on Ti surface improved the osteogenic and antibacterial properties, which may have promise for use in dental implantation. [ABSTRACT FROM AUTHOR]