PURPOSE: The aim of this article is to analyze the preference for treatment modality of dentists. MATERIAL AND METHODS: Data of 20,038 patients was involved. Data analysis were done by distribution according to the various kinds of prosthesis, including complete denture, removable partial denture, fixed partial denture, implant-supported dental prosthesis as well as distribution according to the professional titles of the dentists finishing the treatment, including resident and professors. RESULTS: The number of cases of dental prosthesis increased year by year. 61.06% of the patients accepted fixed partial denture restoration. The number of patients who accepted implant supported restoration is also increasing year by year. The number of complete denture, implant-supported dental prosthesis finished by professors was larger than that done by residents, while it was contrary for removable partial denture, fixed partial denture, and the difference was statistically significant (P<.05). CONCLUSION: Professors and residents have some difference in the categorization of prosthesis finished. Fixed partial denture and implant-supported dental prosthesis are preferred.
Dental Prosthesis ; Dental Prosthesis, Implant-Supported ; Dentists ; Denture, Complete ; Denture, Partial, Fixed ; Denture, Partial, Removable ; Humans ; Prostheses and Implants ; Prosthodontics ; Statistics as Topic

This study aimed to compare the surface characteristics and the shear bond strength of veneering porcelain of 3D printed 4Y-TZP with milled 4Y-TZP. Thirty disks with 10 mm diameter and 1.2 mm thickness were fabricated. Fifteen were fabricated by 3D printing (Experimental group), and another 15 by milling (Control group). In each group, five were assigned to surface analysis. Surface roughness was measured using a confocal laser microscope. Surface energy was calculated by measuring the contact angles of water and diiodo-methane with a drop-shape analyzer. Another ten specimens were used to evaluate the shear bonding strength of veneering porcelain on the surface of 4Y-TZP. The surface of 3D-printed 4Y-TZP was very smooth, and the surface roughness (Ra, Rq) was significantly lower than that of milled 4Y-TZP (p<0.001). 3D-printed 4Y-TZP showed low wettability compared with milled 4Y-TZP, i.e., the water contact angle was significantly high (p=0.008), and the surface free energy was low (p=0.008). The shear bond strength to veneered porcelain of 3D printed 4Y-TZP was significantly lower than that of milled 4Y-TZP (p<0.001). The surface characteristics of 4Y-TZP were quite different by the manufacturing process. The smooth surface and low wettability of 3D-printed 4Y-TZP could affect its low shear bonding strength to veneering porcelain.

Shortened dental arch (SDA) as a treatment goal is the concept that stable occlusion and enough masticatory force can be achieved by restoration to the second premolars when the situation is not favorable. SDA could be applied both natural teeth and implant supported fixed prostheses. This case dealt with a patient who has grade 2 intellectual disability and a lot of missing teeth. Because of intellectual disability, patient cooperation during treatment could not be expected. Therefore every treatment should be done under general anesthesia. In addition to that, ridge resorption around molar area was severe and there were maxillary sinus pneumatization and maxillary sinusitis which increased failure probability. SDA concept was adopted to reduce risk factor and minimize general anesthesia. After the treatment, functional and esthetic improvement was achieved and oral hygiene was fortified by periodic recall check and education.
Anesthesia, General ; Bicuspid ; Bite Force ; Dental Arch ; Humans ; Intellectual Disability ; Maxillary Sinus ; Maxillary Sinusitis ; Molar ; Mouth ; Mouth Rehabilitation ; Oral Hygiene ; Patient Compliance ; Prostheses and Implants ; Risk Factors ; Tooth

STATEMENT OF PROBLEM: Preparation of implant beds with lasers is considered a safe and reliable method, but the accuracy of this technique has not been examined. PURPOSE: The purpose of this study was to evaluate the accuracy and effectiveness of implant bed preparation using an Er,Cr:YSGG laser. MATERIAL AND METHODS: An Er,Cr:YSGG laser was applied to pig rib bone. The laser was employed at a 5.75 W power setting, 30 Hz/sec pulse repetition, and 70 micro sec pulse duration with 50 % water and 60% air spray. According to laser tips the groups were divided as follows; Group 1: paralleled - shaped sapphire tip (0.6 mm phi), Group 2: paralleled - shaped zirconia tip (0.6 mm phi), Group 3: tapered sapphire tip (0.4 mm phi). The Er,Cr:YSGG laser tip was separated by 1 mm from the bone and applied for 15 seconds in a non-contact mode. After the application, the bone was sectioned for specimens. Histologic measurements were determined by computerized morphometry. The length of the prepared bone surface was measured and the width of the entrance was measured. The results were analyzed with one-way ANOVA (P<0.05). RESULTS: The prepared length of group 3 was longer than that of group 2. The prepared bone width was larger than the width of the laser tip in every group. Additional bone removal was observed adjacent to the prepared area and displayed an irregular surface. CONCLUSION & DISCUSSION: Different cutting effects were observed according to the laser tip, emphasizing the importance of proper tip selection in the clinical setting. This preliminary study supported the existence of hydrokinetic effects.
Aluminum Oxide ; Ribs ; Water ; Zirconium

PURPOSE: The aim of this study was to compare the fracture of implant component behavior of external and internal type of implants to suggest directions for successful implant treatment. MATERIALS AND METHODS: Data were collected from the clinical records of all patients who received WARANTEC implants at Seoul National University Dental Hospital from February 2002 to January 2014 for 12 years. Total number of implants was 1,289 and an average of 3.2 implants was installed per patient. Information about abutment connection type, implant locations, platform sizes was collected with presence of implant component fractures and their managements. SPSS statistics software (version 24.0, IBM) was used for the statistical analysis. RESULTS: Overall fracture was significantly more frequent in internal type. The most frequently fractured component was abutment in internal type implants, and screw fracture occurred most frequently in external type. Analyzing by fractured components, screw fracture was the most frequent in the maxillary anterior region and the most abutment fracture occurred in the maxillary posterior region and screw fractures occurred more frequently in NP (narrow platform) and abutment fractures occurred more frequently in RP (regular platform). CONCLUSION: In external type, screw fracture occurred most frequently, especially in the maxillary anterior region, and in internal type, abutment fracture occurred frequently in the posterior region. placement of an external type implant rather than an internal type is recommended for the posterior region where abutment fractures frequently occur.
Humans ; Retrospective Studies ; Seoul

PURPOSE: The purpose of this study was to evaluate bone response to anodized titanium implants coated with the extract of black cohosh, Asarum Sieboldii, and pharbitis semen. MATERIALS AND METHODS: Forty anodized titanium implants were prepared as follows: group 1 was for control; group 2 were implants soaked in a solution containing triterpenoids extracted from black cohosh for 24 hours; group 3 were implants soaked in a solution containing extracts of black cohosh and Asarum Sieboldii for 24 hours; group 4 were implants soaked in a solution containing extracts of pharbitis semen for 24 hours. The implants from these groups were randomly and surgically implanted into the tibiae of ten rabbits. After 1, 2, and 4 weeks of healing, the nondecalcified ground sections were subjected to histological observation, and the percentage of bone-to-implant contact (BIC%) was calculated. RESULTS: All groups exhibited good bone healing with the bone tissue in direct contact with the surface of the implant. Group 2 (52.44 +/- 10.98, 25.54 +/- 5.56) showed a significantly greater BIC% compared to that of group 3 (45.34 +/- 5.00, 22.24 +/- 2.20) with respect to the four consecutive threads and total length, respectively. The BIC% of group 1 (25.22 +/- 6.00) was significantly greater than that of group 3 (22.24 +/- 2.20) only for total length. CONCLUSION: This study did not show any remarkable effects of the extract of black coshosh and the other natural products on osseointegration of anodized titanium implants as coating agents. Further studies about the application method of the natural products on to the surface of implants are required.
Animals* ; Asarum ; Biological Products ; Bone and Bones ; Cimicifuga* ; Methods ; Osseointegration ; Rabbits ; Semen ; Tibia ; Titanium*