• The Journal of Korean Academy of Prosthodontics
• /
• v.35 no.3
• /
• pp.535-543
• /
• 1997

In order to compare the accuracy of impression technique using the addition silicone putty and improved heavy body material, impression were taken for the natural 6 maxillary anterior teeth, and for the metal mast model that has full arch shape with 4 cylindrical abutment teeth. Marginal gingiva was retracted by routine method using retraction cord, and two techniques were tried to compare the length of impression materials in the gingival sulcus. This was aimed to see the effect of viscosity and hydraulic pressure of impression materials for the subgingival impression. Impressions for the full arch-shaped metal master model were taken to compare the linear stability of the different impression materials and their related techniques. The conclusions were as belows : 1. The one-step impression technique showed longer extension of impression material in gingival sulcus than two-step impression technique. 2. High viscosity and hydraulic pressure of impression material were useful to take subgingival impression. 3. There was no statistically significant difference for the two-dimensional accuracy of impression technique, but two-step technique showed better trend than one-step technique.

• Journal of the Korean Academy of Esthetic Dentistry
• /
• v.26 no.1
• /
• pp.24-38
• /
• 2017

Prosthetics procedures in dental clinics 1) Tooth preparation 2) Temporary restoration 3) Post and core 4) Impression 5) Cementation of final prosthesis The final step in the prosthodontic procedure is the fitting of the final prosthesis to the patient's abutment with an exact fit and occlusal relationship. By the way, this final prosthesis is not made in the clinic but is made in the dental lab and comes to the clinic with some time difference. In the clinic, the only medium to deliver the patient's oral information to the dental laboratory is the impression. However, many errors occur in this process. Dentists and dental technicians should try to identify the cause and make an accurate prosthesis to reduce this error.

• Korean Chemical Engineering Research
• /
• v.56 no.2
• /
• pp.240-244
• /
• 2018

There is growing concern about cross infection among the patients to patients, patients to staffs, and tools to patients in healthcare facilities, especially in dentistry. In this study, the most widely used dental impression materials were prepared and the synergy effect of Chlorhexidine and essential oil on antimicrobial activity was examined in the impression materials. Chlorhexidine concentration of 0.1 wt% and 0.5 wt% showed no antimicrobial activity on Escherichia coli (E. coli) and Candida albicans. At 1.0 wt% Chlorhexidine, 0% of E. coli and 34.7% of Candida albicans were survived. Bergamot (Essential oil) concentration of 0.5 wt% and 1.0 wt% showed no antimicrobial activity on E. coli. At 2.0 wt% Bergamot oil, 71.9% of E. coli were survived. Tea tree oil (Essential oil) of 0.5 wt% showed no antimicrobial activity on E. coli. At 1.0 wt% Tea tree oil, 11.2% of E. coli was survived. At 2.0 wt% Tea tree oil, no E. coli was survived. However, no E. coli was survived at the concentration of 0.8 wt% Bergamot with 0.3 wt% Chlorhexidine. At the concentration of 0.8 wt% Tea Tree oil with 0.3 wt% Chlorhexidine, 1.3% of E. coli were survived. The experimental results showed that the synergy effects between Chlorhexidine and essential oils on antimicrobial activity were prominent.

• The Journal of Advanced Prosthodontics
• /
• v.11 no.5
• /
• pp.271-279
• /
• 2019

PURPOSE. The newest technologies for digital implant impression (DII) taking are developing rapidly and showing acceptable clinical results. However, scientific literature is lacking data from clinical studies about the accuracy of DII. The aim of this study was to compare digital and conventional dental implant impressions (CII) in a clinical environment. MATERIALS AND METHODS. Twenty-four fixed zirconia restorations supported by 2 implants were fabricated using conventional open-tray impression technique with splinted transfers (CII group) and scan with Trios 3 IOS (3Shape) (DII group). After multiple verification procedures, master models were scanned using laboratory scanner D800 (3Shape). 3D models from conventional and digital workflow were imported to reverse engineering software and superimposed with high resolution 3D CAD models of scan bodies. Distance between center points, angulation, rotation, vertical shift, and surface mismatch of the scan bodies were measured and compared between conventional and digital impressions. RESULTS. Statistically significant differences were found for: a) inter-implant distance, b) rotation, c) vertical shift, and d) surface mismatch differences, comparing DII and CII groups for mesial and distal implant scan bodies ($P{\leq}.05$). CONCLUSION. Recorded linear differences between digital and conventional impressions were of limited clinical significance with two implant-supported restorations.

• Elastomers and Composites
• /
• v.36 no.2
• /
• pp.102-110
• /
• 2001

The three types of surfactants such as nonylphenoxy poly(ethylene) ethanol homologues, caster oil poly(ethylene) ethanol homologues, and sodium perfluoroalkyl carboxylates are used to improve the wettability of rubber impression material. Among the surfactants, the usage of sodium perfluoroalkyl carboxylates containing fluoro group resulted in the lowest surface energy of impression material and the result gave the positive effect on the wettability of rubber impression material to teeth. Also, the anti-foaming agents were used to reduce or remove the hydrogen gas generating on the impression material by reaction. In the case of rubber impression material containing sodium perfluoroalkyl carboxylate as a surfactant, it was found that the tear strength of rubber impression material increased over 3 N/mm with the addition of anti-forming agent. Therefore, the anti-foaming agent could contribute to the mechanical property of rubber impression material without the change of surface property.

• The Journal of the Korean dental association
• /
• v.15 no.5
• /
• pp.323-324
• /
• 1977

• The Journal of the Korean dental association
• /
• v.15 no.6
• /
• pp.389-391
• /
• 1977

• The Journal of the Korean dental association
• /
• v.6 no.1
• /
• pp.3-7
• /
• 1967

• The Journal of the Korean dental association
• /
• v.25 no.6 s.217
• /
• pp.514-515
• /
• 1987

• The Journal of the Korean dental association
• /
• v.15 no.4
• /
• pp.261-263
• /
• 1977