• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.5
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• pp.2197-2202
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• 2011

In this study, we propose a new short dental implant and investigate its bio-mechanical characteristics by using three dimensional finite element analyses. The proposed dental implant has the central cavity which can be integrated with the core of cancellous bone remained by trepanning drill. We take the Bicon short implant as a reference model for studying the effects according to the shape of cavity. The parametric finite element model using ANSYS APDL has been built to determine which length, diameter and thread of central cavity would be effective to dissipate stress. The reduction of undesirable stress in adjacent bone which can suppress bone defects and the eventual failure of implants. The numerical results shows that the cavity of well-determined shape has the beneficial effects on reducing the bone absorption in cancellous bone.

• Journal of Korean society of Dental Hygiene
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• v.7 no.4
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• pp.481-493
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• 2007

It follows in increase of the old age population and the loss of teeth increases, also the supplement prosthetics treatment which is caused by loss of teeth is various and it develops and the dentistry implant demand is increasing. This study enforced a self-administered survey with 197 dental personnels employed in dental hospitals, dental clinics from August 15, 2007, to September 15, in the area of Daejeon. It's ultimately intended to serve as a basis for the preparation of more effective, appropriate dental implants education programs for personnels, who take a crucial part in dental implants operation, provide better dental services to patients who are in need of dental implants operation. As the result, the study got the following conclusion. 1. The population sociological feature of dental hospital and dental clinic showed that significant differences of dental service career. Dental service career of dental personnels shows; below 3 years 43.1%, 4~6 years 35.3%, more than 7 years 21.6% in dental hospitals, below 3 years 29.5%, 4~6 years 28.1%, more than 7 years 42.5% in dental clinics(p=0.027). 2. The average score of personnels knowledge in dental implants was 3.67point, from analyzing the knowledge on dental implants of dental personnels from dental health-care settings, dental personnels employed in dental hospitals scored relatively higher than in dental clinics(p=0.129). Dental personnels with 4~6 years of experience scored the highest(p=0.002). 3. The average score of dental personnels compliance in dental implants was 3.92point, from analyzing the compliance of dental implants of dental personnels from dental health-care settings, dental personnels employed in dental hospitals scored relatively higher than in dental clinics(p=0.006). Dental personnels with 4~6 years of experience scored the highest(p=0.707). 4. The contingency coefficient between dental implants general knowledge and the general compliance(r=0.233, p=0.001), operation knowledge and operation compliance(r=0.332, p=0.000), maintenance knowledge and maintenance compliance(r=0.236, p=0.001). 5. Recently dental implants is emerging as one of the important medical services in the dental treatment sector. From analyzing the compliance of dental implants of dental personnels in dental health-care settings, dental personnels employed in dental hospitals scored relatively higher than in dental clinics. Consequently, the effort of the dentist and the dental personnels demanded to be earnestly to improves the difference of the knowledge and compliance against the dental implants of the dental personnels in dental health-care settings, it is thought that with reinforcement of effective role share and professionalism to success of dental implants, more system and the specialty dental implants education which is standardized continuously must be provided to all dental personnels.

• Radiation Oncology Journal
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• v.16 no.2
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• pp.167-175
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• 1998

Purpose : It is not a simple task to achieve the ideal isodose curve with a standard vaginal applicator or sing1e plane needle impant in the paravaginal tissue when primary or recurrent gynecological neoplasms(cervical cancers, vaginal cancers and vulvar cancers) are treated as a boost following external beam radiotherapy. The authors introduce the development and construction of a simple, inexpensive, customized applicator for volume implant to maximize the radiation dose to the tumor while minimizing the dose to the rectum and the bladder. Materials and Methods : Nine patients underwent Ir-192 transperineal interstitial implantation for either recurrent(5 cases) or primary(3 cases) cervical cancers or primary vaginal cancer(1 case) between August 1994 and February 1998 at Ajou university hospital. First 3 cases were performed with a sing1e plane implant guided by digital palpation. Because of inadequate isodose coverage in the tumor volume in first 3 cases, we designed and constructed interstitial vaginal applicator for volume implant to improve tumor dose distribution and homogeneity while sparing the surrounding normal tissue. Our applicators consist of vaginal obturator and perineal template that made of the clear acrylamide and dental mold material$(Provil^{(R)})$. The applicators were customized individually according to the tumor size and its location Both HDR and LDR irradiation were given with these applicators accomodating 6 Fr needles(Microselectron Nucletron). The pretreatment planning prior to actual implant was performed whenever possible. Results : Needles can be inserted easily and evenly into the tumor volume through the holes of templates, requiring less efforts and time for the implant procedure. Our applicators made of materials available from commercial vendors. These have an advantage that require easy procedure, and spend relatively short time to construct. Also it was possible to fabricate applicators to individualize according to the tumor size and its location and to achieve the ideal isodose coverage. We found an accurate needle arrangement and ideal dose distribution through the CT scan that was obtained in 3 cases after needle implant. Three patients with primary cervical and vaginal cancers were controlled locally at final follow up. But all recurrent cases failed to do so. Conclusion : The authors introduce inexpensive, simple interstitial vaginal templates which were self-designed and constructed using materials available from commercial vendors such as acrylanide and dental mold material $(Provil^{(R)})$.