• The Journal of the Korean dental association
• /
• v.55 no.7
• /
• pp.457-466
• /
• 2017

In the case of failed fixed implant prosthesis accompanied by abutment screw fracture, fractured screw fragment must be removed to use the existing implant fixtures. A 61-year-old male patient, who had a failed maxillary fixed implant prosthesis accompanied by three abutment screw fracture, hoped to reconstruct the maxillary implant prosthesis, while maintaining the existing implant fixtures. To use the existing implant fixtures, fractured screw fragments were removed. A maxillary implant overdenture using available existing implants was planned. Bar-attachment with Locator was used for implant splinting, denture stability, and retention. Final impression was taken after treatment of peri-implantitis. Jaw relation registration was taken to evaluate available interarch space for bar-attachment. After fabricating bar-attachment, centric relation was taken. Implant overdenture using bar-attachment with Locator was delivered after wax-denture evaluation. This case report showed that a satisfactory clinical result was achieved by implant overdenture using existing implant fixtures in a maxillary edentulous patient.

• Journal of Dental Anesthesia and Pain Medicine
• /
• v.23 no.1
• /
• pp.9-17
• /
• 2023

Background: Dental evaluation and protection are important for preventing traumatic dental injuries when patients are under general anesthesia. The objective of the present study was to develop a questionnaire based on dentition-related risk factors that could serve as a valuable tool for dental evaluation and documentation. Methods: We developed a questionnaire for dental evaluation before administration of general anesthesia, investigated the association between patient-and-dentist responses and mouthguard fabrication, and assessed response agreement between 100 patients. Results: Protective mouthguards were fabricated for 27 patients who were identified as having a high risk of dental injury. There was a strong association between dentists' responses and mouthguard fabrication, depending on the general oral health status, use of ceramic prosthesis, presence of masticatory pain related to periodontal diseases, gingival edema, and implants (P < 0.05). Response agreement between patients and dentists for items related to dental pain, loss of dental pulp vitality, root canal therapy, dental trauma, aesthetic prosthesis, tooth mobility, and implant prosthesis was high (Cohen's kappa coefficient κ ≥ 0.6). Conclusions: A high agreement was observed between patient-dentist responses and a strong association with mouthguard fabrication for items pertaining to ceramic prosthesis, masticatory pain, and dental implants. Patients with a "yes" response to these items are recommended to undergo a dental evaluation and use a dental protective device while under general anesthesia.

• The Journal of Advanced Prosthodontics
• /
• v.4 no.4
• /
• pp.248-253
• /
• 2012

Maxillary obturator prosthesis is the most frequent treatment option for management of partial or total maxillectomy. Heavy weight of the obturators is often a dislocating factor. Hollowing the prosthesis to reduce its weight is the well established fact. The alternate technique to hollow-out the prosthesis has been described in this article which is a variation of previously described processing techniques. A pre-shaped wax-bolus was incorporated inside the flasks during packing of the heat-polymerized acrylic resin to automatically create the hollow space. The processing technique described is a single step flasking procedure to construct a closed-hollow-obturator prosthesis as a single unit. To best understand the technique, this article describes management of a patient who had undergone partial maxillectomy secondary to squamous cell carcinoma rehabilitated with a hollow-obturator prosthesis.

• The Journal of Advanced Prosthodontics
• /
• v.3 no.4
• /
• pp.204-215
• /
• 2011

PURPOSE. The aim of this retrospective study is to analyze the relationship between local factors and survival rate of dental implant which had been installed and restored in Seoul Veterans Hospital dental center for past 10 years. And when the relationship is found out, it could be helpful to predict the prognosis of dental implants. MATERIALS AND METHODS. A retrospective study of patients receiving root-shaped screw-type dental implants placed from January 2000 to December 2009 was conducted. 6385 implants were placed in 3755 patients. The following data were collected from the dental records and radiographs: patient's age, gender, implant type and surface, length, diameter, location of implant placement, bone quality, prosthesis type. The correlations between these data and survival rate were analyzed. Statistical analysis was performed with the use of Kaplan-Meier analysis, Chi-square test and odds ratio. RESULTS. In all, 6385 implants were placed in 3755 patients (3120 male, 635 female; mean age $65{\pm}10.58$ years). 108 implants failed and the cumulative survival rate was 96.33%. There were significant differences in age, implant type and surface, length, location and prosthesis type (P<.05). No significant differences were found in relation to the following factors: gender, diameter and bone quality (P>.05). CONCLUSION. Related factors such as age, implant type, length, location and prosthesis type had a significant effect on the implant survival.

• Journal of Technologic Dentistry
• /
• v.25 no.1
• /
• pp.29-40
• /
• 2003

This study was aimed to verify a comparison by dental alloys upon the marginal fitness of dental prosthesis. Firstly, we waxed up on 45 epoxy resin dies, pressed the margin with hands, and identified the marginal fitness with microscope. And we made a single direct spruing system type of sprue by 3 dental alloys - metal crown alloys, PFM crown alloys, and gold crown alloys - each 15, total 45 waxing up, adjusting W/P ratio and invested the cast ring. Then, we made the dental prosthesis using the electric casting machine. In these processes we followed the manufacturer's instructions, in order to maintain the other conditions from the inner and outer, which included investment and burning out. After we tried on the dental prosthesis on epoxy resin dies, we have got the means of marginal gap at 9 points with same distances, around the cervical line which was checked already, using microscope($\times$300). The results of this study were as follows : 1. Metal crown alloys showed 2.9% better in marginal fitness than PFM crown alloys, and the difference was not statistically significant(P=0.497). 2. Gold crown alloys showed 31.3% better in marginal fitness than Metal crown alloys, and the difference was statistically significant(P=0.004). 3. Gold crown alloys showed 32.4% better in marginal fitness than PFM crown alloys, and the difference was statistically significant(P=0.002). 4. We saw that Gold crown alloys was the best dental alloys in the marginal fitness among the three.(P=0.049).

• Journal of the Korean Academy of Esthetic Dentistry
• /
• v.23 no.2
• /
• pp.77-79
• /
• 2014

There are several factors affected fractures of full contour zirconia (FCZ) dental prosthesis in laboratory process. First, residual moisture can cause zirconia cracks. Complete dry is requisite before zirconia sintering to prevent zirconia cracks. Second, slow cooling rate is essential to prevent cracks during zirconia sintering process. Cracks in bridge pontic area, thick dental implant prosthesis can be prevented by slow cooling rate such as 3 degree Celsius per minute during zirconia sintering. Third, slow heating rate and slow cooling rate during staining and glazing procedure is necessary to inhibit thermal shock of sintered dental zirconia. Lower preheat temperature of porcelain furnace is recommended. Finally, using diamond disc to open embrasure can lead cracks.

• Journal of Dental Anesthesia and Pain Medicine
• /
• v.19 no.2
• /
• pp.119-123
• /
• 2019

Foreign body aspiration in dental clinics is the most common cause of respiratory emergencies. There are no reports on foreign body aspiration during dental treatment under stable general anesthesia because the patient neither has voluntary movements nor reflex actions. This is a case report on the fall of a prosthesis in the larynx, which occurs rarely under general anesthesia. During the try-in procedure, the prosthesis slid from the surgeon's hand and entered the retromylohyoid space, and while searching for it, it passed down the larynx to the endotracheal tube balloon, leading to a dangerous situation. The prosthesis was promptly removed using video-assisted laryngoscope and forceps, and the patient was discharged without any complications.

• Journal of Technologic Dentistry
• /
• v.41 no.2
• /
• pp.149-156
• /
• 2019

Purpose: Prosthodontics for edentulous patients is a treatment technique using implant, which has impactful results in retention and support effects. Methods: As a retention technique, SCRP (screw and cement retained implant prosthesis) has reported in many studies as a beneficial method for both patients and curers, which can reduce errors in process of making abutment and top implant. Results: Prosthesis manufacturing, as polymerization method of hardened resin teeth with thermoplastic resin, is helpful for patients with aesthetic and financial situations regarding residual ridge and interocclusal relationship, also indicates reliable results in both retention and care. Conclusion: Using SCRP technique, we notably obtained a clinical and aesthetic outcome from five implants in anterior tooth, which are half fixable and detachable implants on screw of implant abutment by the technicians at anytime.

• The Journal of the Korean dental association
• /
• v.52 no.6
• /
• pp.332-345
• /
• 2014

In recent years, precision machining of the dental prosthesis by computer assisted system is becoming pervasive in clinical dentistry. Prosthesis fabricating system that is designed by computer software and made by computer devices is called as a CAD/CAM (Computer-Aided Design/Computer-Aided Manufacturing) system. By the use of dental CAD/CAM system, the improvement of marginal compatibility and mechanical properties in prosthesis can be obtained more effectively, an aesthetic quality by using new materials such as zirconia can be increased. Also, the restoration process can be simple and efficient, the production time can be shortened, the process of manufacture can be standardized, and the mass production is possible. What is clear is that these benefits are theoretically possible, but the dentist or dental technician must understand the CAD/CAM basic principles and limitations for obtaining the maximum advantages of CAD/CAM system. For this reason, this article will be presented about the basic principles of CAD/CAM system and the factors of error that might occur in the CAD/CAM process based on my empirical study.

• Journal of Technologic Dentistry
• /
• v.43 no.4
• /
• pp.202-209
• /
• 2021

By classifying temporary denture production for surgical guides, digital guide-based surgery, and final prosthesis production, the problems of each process were assessed in advance and the factors that could be improved were confirmed in this study. The manufacturing process of fusion dental prosthesis uses virtual programs and computed tomography images to manufacture devices using the latest technologies of computer-aided design/computer-aided manufacturing and three-dimensional printing, which enables implants to be placed in the desired location in advance. Moreover, implant placement is not dependent on the skill and condition of the dentist, and because it uses a computer system, it can always be performed at a constant and optimal position. This can reduce the remanufacturing rate compared with the general method, shorten the treatment period, and eliminate patient discomfort. Unlike the traditional method of using impression materials and plaster models, digital fusion dental prostheses would be evaluated as a technology for producing prosthesis through professional design technology and communication.