As an efficient controlled release system for rhBMP-2, a functional nanoparticle-hydrogel complex, incorporated with matrix metalloproteinase( MMP) sensitive peptide cross-linker, was developed and used as a bone transplant. In vivo bone formation was evaluated by soft x-ray, histology, alkaline phosphatase(ALP) activity and mineral contents analysis, based on the rat calvarial critical size defect(8mm in diameter) model. Significantly, effective bone regeneration was achieved with the rhBMP-2 loaded MMP sensitive hyaluronic acid(HA) based hydrogel- Nanoparticles(NP) complex, as compared to only MMP HA, the MMP HA-NP without rhBMP-2, or even with the rhBMP-2. These improvements included the formation pattern of bone and functional marrow, the degree of calcium quantification, and the ALP activity. These results indicate that the MMP sensitive HA with nano-particle complex can be a promising candidate for a new bone defect replacement matrix, and an enhanced rhBMP-2 scaffold.
Traditional surgical method or injection using filler is performed for soft tissue augmentation. Surgical methods have disadvantage of surgical morbidity. Commercially available injectable materials have the disadvantages such as resorption, short-term effect. repeated application and hypersensitivity. Significant shortcoming of cell therapy using autologous fibroblasts is delay of treatment effect. Chitosan/β-glycerol phosphate (GP) solution has thermosensitive property and allows sol-gel transition at physiologic pH and temperature. These properties may resolve the delay of treatment effect. The purposes of this study are to evaluate the viscosity and pH changes of chitosan/β-GP solutions and to evaluate the effect of chitosan/β-GP solution on fibroblast proliferation and production of collagen. We measured the viscosity and pH as function of temperature, of the solution containing 1:0.7, 1:0.75, 1:0.8 chitosan (1, 10, 100, 700 kDa) /β-GP. Fibroblasts from ears of 5 rats were cultured in chitosan/β-GP solutions for 3 weeks. Cell proliferation and collagen contents were measured every week with WST (water-soluble tetrazolium salt) assay and Collagen assay respectively. The Results are 1) Chitosan(100 kDa<)/β-GP solution (1:0.75) showed sol-gel transition at physiologic pH and body temperature and injectable properties. It will enable to resolve the delay in treatment effect 2) Cell proliferation and total collagen contents of the control group were increased with time. However, these decreased after the 1st week in experimental group 3) Collagen contents in the experimental group are higher than that of control group. Chitosan/β-GP solution may provide favorable conditions for cell function
Recently, an increasing number of bisphosphonate related osteonecrosis of the jaw(BRONJ) is being reported. A guideline has been already established in the US, but it does not seem to be fully recognized by clinicians in Korea. Therefore, a survey study was done to inform and have clinicians realize the seriousness of BRONJ. 1,341 practitioners were randomly selected out of 13,405 practitioners(by Feb of 2008, KDA) in Korea. A questionnaire was given to them between May to July in 2008. Questions were designed to investigate each respondent’s experience term years in the clinic, occupation, speciality, awareness on risk of bisphosphonate, experience on treating osteonecrosis patients, awareness about the guideline on BRONJ suggested by AAOMS and whether if they ask about bisphosphonate medication history to patients before invasive treatment. 45.1% of the clinicians have reported on experiencing delayed healing on bone exposed site after extraction both in the maxilla and the mandible. However, clinicians have asked the patients whether if they are on bisphosphonate or not in only 15.1% of these cases. 56.5% of the clinicians simply knew about BRONJ but only 28.9% of the clinicians were aware that bisphosphonate can cause osteonecrosis after invasive dental treatment. Only 19.3% knew about the contents of guideline on BRONJ and 57.2% were aware of the seriousness of BRONJ. Clinicians with shorter clinical experience term were more aware of BRONJ and the guideline on BRONJ than the experienced clinicians. But awareness of the possibility of BRONJ after invasive dental treatment were about the same regardless of their clinical experience. The results show that Korean clinicians need to be more aware about BRONJ. Data on BRONJ cases in Korea should be collected and provided with additional education to let Korean clinicians know and be more aware about BRONJ.
Objective : Recently, we are interested in bisphosphonate related osteonecrosis of the jaw (BRONJ). Most of patients with osteonecrosis have taken medicine bisphosphonate for a long time. But the mechanism of osteonecrosis in BRONJ was not clarified yet. The aim of this study is to evaluate the difference of bone healing effect after bone graft from ilium to maxillary sinus in rabbits between zoledronate-treated and zoledronate-not treated groups. Method : The subjects was divided into two groups. The experimental group was 9 rabbits, treated with intraperitoneal administration of zoledronate( 0.06mg/kg) once per week for 3 weeks. In control group, same procedure was applied but administerd saline instead of zoledronate. After 4 weeks, surgical operation under local anesthesia (ketamine 3.0cc, xylazine 1.0cc) was done. At postoperative 1, 2, 4, 8 weeks later, each rabbits were sacrificed and removed the bone grafted area. Gross, radiologic and histopathologic exminations of bone grafted area were performed. Result : There were no conspicuous differences of radiological findings between experimental and control groups in any experimental weeks. In experimental group, new bone formation appeared earlier than control group at 1 week after operation, and maturation of bony tissue were more conspicuous at 2 and 4 weeks after operation, compared with control group. In 8 weeks after operation, similar microscopic findings were noted in both groups. Conclusion : In the bisphosphonate-treated rabbits, new bone formation in the bone grafted area appeared earlier and bony maturation was more concpicuous, even though there were no significant differences of gross and radiological findings. These findings suggest that bisphosphonate might be promotive effect in the healing process in early stage after administration.
Objectives : Administration methods of antibiotics implements a variety for indications and diseases. Therefore, it is impossible to produce a single guideline. Many antibiotics have been prescribed without specific index, by practicians for a long period of time. In general dental practice and oral and maxillofacial surgical practice, there is not a guidelines for antibiotics. Therefore, there is a dependency on pre-existent methods rather than following an exact guideline. Consequently, a controversy was issued that prescription of antibiotics tend to be misused or abused. And it is also direct relation to the tolerance of antibiotics as well. Moving forward, in this review we will be analyzing the exact usage and indication of antibiotics in dental treatment. Materials and Methods : 29 published articles of both domestic and international were researched through Pubmed and Kormed, and the review from these articles were performed accordingly. We examined the administration of antibiotics through the objective usage, that classified prophylactic and therapeutic. Results : For therapeutic usage, empirical prescription is mandatory for the first step. Next is to moderate the empirical prescription depending upon the result of its culture. Administration of antibiotics must be kept for 2days after the symptoms disappear. For a prophylactic use, we can generally pr escribe antibiotics to prevent local infection or systemic infection. Although the method of prescription and neccessity of antibiotics to prevent local in fection are controversial, exact guidelines of antibiotics to prevent systemic infection are established by AHA. Conclusion : Most crucial concept for prescript antibiotics is to determine if it is adequately suitable for all circumstances. In this decision making, a guideline for prescription of antibiotics in various dental surgical practice is necessary. This guideline can reduce the misusage and disusage of a ntibiotics in general dental practices and oral and maxillofacial surgical practices.
Purpose : The purpose of this study is to evaluate 7-year survival rate of implants placed without bone graft in posterior maxilla and compare the survival rate by the age and gender of patient, length and diameter of implant, region of implant placement, bicortical engagement of fixture, and connection of prosthesis. Material and methods : 78 patients (170 implants) who visited our institution from 2002 to 2007 and were followed up with panoramic view and medical records. Kaplan-Meier survival analysis and Log Rank (Mantel-Cox) test were used. Results and conclusions : A 7-year cumulative survival rate for implants placed in posterior maxilla without sinus graft was 95.3%. The survival rate in men was 91.8%, significantly lower than 98.8% in woman.(p<0.05) .However, the survival rate by the length of the implants did not show any significant differences.(p>0.05), while the wide platform implant resulted in 85% survival rate which was statistically lower than 98.5% in regular platform. The posterior maxillary implants engaged bicortically showed 97.6% of 7-year Survival rate, comparing 88.6% in not engaged implants. The survival rate of the single implant was 91.2%, while 98.5% in splinted prosthesis. Therefore, the bicortical engagement of the fixtures and splinted prosthesis may be recommended to get a long-term survival rate in posterior maxilla.
Synovial chondromatosis is a rare, benign, monoarticular arthropathy that is characterized by the development of highly cellular, metaplastic cartilaginous nodules in the synovial membrane. It commonly affects larger joints such as the knee, elbow, wrist, shoulder, and hip. Synovial chondromatosis of the temporomandibular joint(TMJ) is rare. Moreover, the temporal involvement of synovial chondromatosis without connection with joint is greatly rare. A 44-year-old women had experienced pain of the right TMJ area and limitation of mouth opening. MRI and CT revealed multiple calcified loose bodies and widening in right upper joint space of TMJ and osteolytic lesion in right temporal bone. Treatment consisted of removal of multiple loose bodies, resection of the osteolytic lesion through the preauricular approach. She was diagnosed with primary transitional synovial chondromatosis of TMJ with involvement of temporal bone. In spite of remaining of the loose bodies, pain and mouth opening improved and there have been no recurrence of signs and symptoms for 5 years follow up.
There are several oral lesions related with AIDS, such as candidiasis, hairy leukoplakia, Kaposi’s sarcoma, aphthous stomatitis, lichen planus, and other opportunistic infectious diseases. Among the others, Kaposi’s sarcoma, the most common malignant tumor associated with AIDS, is closely linked to the number of CD4+ T cell. Kaposi’s sarcoma often occurs in palate, the most prone site, and has characteristic clinical features in most cases. Sometimes, the tumor induces underlying bone destruction at late stage. We report a case of a 27 year-old man with AIDS-associated Kaposi’s sarcoma at left lower retromolar triangle, parapharyngeal area and discuss the management of AIDS patients in dentistry.
Out of all oral malignant tumor, malignant lymphoma occurs in only 3.5%. Especially, most of the primary malignant lymphomas, which occur in the head & neck region are high-grade diffuse large B-cell lymphoma and mucosa-associated lymphoid tissue (MALT) marginal zone B-cell lymphoma is very rare. In the head & neck region, malignant lymphoma is reported to occur in the thyroid, salivary gland, trachea, larynx, orbital lobe and the Waldeyer’s ring. Among the Waldeyer’s ring, palatal tonsil is reported to be the most common region, but, only 1 case report was published in Korea. Until now, there were no case reports of MALT lymphoma that occurred in the tongue. The purpose of this case report is to report and discuss on a case of MALT lymphoma of the tongue.