• Restorative Dentistry and Endodontics
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• v.27 no.3
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• pp.284-289
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• 2002

Background : The purpose of the present study was to evaluate the direct and indirect composite restorations which had been placed for 1 year Methods : The composite restorations which had been placed between 1999. Mar and 1999, Dec was evaluated after 1 year For direct restorations. Spectrum (Dentsply, USA) and Z100 (3M, USA) were used in the anterior teeth and Surefil (Dentsply, USA) were used. For class V restorations of anterior and posterior teeth. Spectrum was used. For indirect restorations, Targis/Vectris system (Vivadent/Ivoclar, Liechtenstein) was used 2 examiners evaluated marginal quality, proximal contact. discoloration, presence of 2$^{nd}$ caries, loss of filling and hypersensitivity of restorations. The restorations was clinically evaluated by modified methods based on USPHS. Results : 60 teeth were evaluated. 59 were clinically acceptable and 1 restoration which was placed in class v cavity in the posterior tooth was fallen out. In most cases, the restorations were clinically accept-able. For restorations which had been directly placed in the class II cavities, loose proximal contact was indicated as the main complaints. Conclusions : Most of Anterior and posterior restorations which bad been directly or indirectly placed for 1 year were clinically acceptable. For posterior teeth, loose proximal contact was indicated as the main problem in the directly placed Class II restorations. Long term clinical study is needed.

• The Journal of Advanced Prosthodontics
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• v.14 no.1
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• pp.56-62
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• 2022

PURPOSE. The aim of this study was to investigate shade changes in fully- and pre-crystalized CAD-CAM lithium disilicate crowns after the required and additional firing processes. MATERIALS AND METHODS. One hundred and five crowns of shade A1 with high translucency were milled out of CAD-CAM lithium disilicate blocks and categorized as follows (n = 15): (1) restorations fabricated from Straumann n!ce with no additional sintering process; (2) restorations fabricated from Straumann n!ce with one additional sintering process; (3) restorations fabricated from Straumann n!ce with two additional sintering processes; (4) restorations fabricated from Amber Mill with one sintering process; (5) restorations fabricated from Amber Mill with two sintering processes; (6) restorations fabricated from IPS e.max CAD with one sintering process; (7) restorations fabricated from IPS e.max CAD with two sintering processes. All restorations were evaluated with a color imaging spectrophotometer. RESULTS. All restorations presented some color alteration from the original shade both after a single and after two firing processes. CONCLUSION. The required and additional sintering processes for restorations fabricated with chairside CAD-CAM lithium disilicate blocks cause an alteration of the original shade selected. Shade A1 high translucency restorations tend to change to a more yellowish B1 shade after a sintering process.

• The Journal of Korean Academy of Prosthodontics
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• v.32 no.3
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• pp.359-367
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• 1994

The number and the distribution of fixed restorations including crowns, fixed bridges, Maryland bridges, periodontal splints and cast cores were statistically investigated with two thousand seven hundred and thirty cases of crowns and bridges placed at the Department of Prosthodontics of Seoul National University Hospital, from January 4th to December 31st, 1988. The results were as follow : 1. Among the fixed restorarions, single crowns were 46.9% , fixed bridges were 41.9%, Maryland bridges were 5.0%, periodontal splints were 0.6% and cast cores were 5.6%. 2. Three thousand nine hundred and ninty two teeth were restored with the fixed restorations, among them cast gold restorations were 47.2% and metal-ceramic restorations were 52.8%. 3. Cast gold restorations of the maxillary posteriors occupied 98.5% of the maxillary cast gold restorations, and 99.7% of the mandibular cast gold restorations and metal-ceramic restoration of maxillary anteriors occupied 68.4% of the maxillary metal-ceramic restorations, and 38.7% of the mandibular metal- ceramic restorations. 4. It is recommended that the curriculum of the dental school for undergraduated students and graduated students should be changed to accomodate the relative importance of the restorations.

• The korean journal of orthodontics
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• v.20 no.3 s.32
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• pp.583-591
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• 1990

If the bond strength is sufficient to resist orthodontic force, orthodontic brackets can be bonded to restorations. Orthodontic brackets were bonded to composite resin and glass ionomer cement restorations with no-mix adhesive or glass ionomer cement. The shear bond strength of adhesives bonded to restorations was studied in vitro. Orthodontic brackets were bonded to 10 extracted natural teeth, 40 composite resin restorations and 40 glass ionomer restorations. The surfaces of composite resin restorations were roughened or applied with bonding agent (Scothbond) after surface roughening. The surfaces of glass ionomer cement restorations were conditioned with acid etching or applied with Scotchbond to etched surface. The adhesive was no-mix resin or glass ionomer cement. The shear bond strength was measured. The results were as follows: 1. Orthodontic brackets could be bonded to composite resin restorations effectively as they could be bonded to acid etched enamel with no-mix adhesive. The shear bond strength was sufficient to resist orthodontic force and was not affected by bonding agent greatly. 2. The shear bond strength of no-mix adhesive bonded to acid etched glass ionomer cement restorations was sufficient to resist orthodontic force. However. the fracture risk of glass ionomer cement restorations was increased during debonding. The bonding agent couldn't increase the shear bond strength greatly. 3. The shear bond strength of glass ionomer cement bonded to glass ionomer cement restorations was lower than that of no-mix adhesive. The shear bond strength was sufficient to resist orthodontic force and was greatly decreased by bonding agent. 4. The shear bond strength of glass ionomer cement bonded to composite resin restorations was too low to resist orthodontic force.

• Restorative Dentistry and Endodontics
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• v.18 no.2
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• pp.501-506
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• 1993

The purpose of this study was to observe the longevity of amalgam and composite resin fillings in Korea. The number of placement of restorations was 760 amalgams and 415 composite resins. The amalgam restorations inserted because of primary caries were 61 % and replacement of amalgam restorations were 39%, and composite restorations inserted because of primary caries were 62 % and replacement of composite restorations were 38 %. The median longevity of failed amalgam restorations was 3 years and the madian longevity of failed composite restorations was 2 years. The main reason of replacement of amalgam and composite resin restorations was secondary caries.

• Restorative Dentistry and Endodontics
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• v.47 no.1
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• pp.5.1-5.11
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• 2022

Objectives: This study aimed to assess the clinical longevity of a bulk-fill resin composite in Class II restorations for 3-year. Materials and Methods: Patient record files acquired from the 40 patients who were treated due to needed 2 similar sizes Class II composite restorations were used for this retrospective study. In the experimental cavity, the flowable resin composite SDR was inserted in the dentinal part as a 4 mm intermediate layer. A 2 mm coverage layer with a nano-hybrid resin composite (CeramX) was placed on SDR. The control restoration was performed by an incremental technique of 2 mm using the nano-hybrid resin composite. The restorations were blindly assessed by 2 calibrated examiners using modified United States Public Health Service criteria at baseline and 1, 2, and 3 years. The data were analyzed using non-parametric tests (p = 0.05). Results: Eighty Class II restorations were evaluated. After 3-years, 4 restorations (5%) failed, 1 SDR + CeramX, and 3 CeramX restorations. The annual failure rate (AFR) of the restorations was 1.7%. The SDR + CeramX group revealed an AFR of 0.8%, and the CeramX group an AFR of 2.5% (p > 0.05). Regarding anatomical form and marginal adaptation, significant alterations were observed in the CeramX group after 3-years (p < 0.05). The changes in the color match were observed in each group over time (p < 0.05). Conclusions: The use of SDR demonstrated good clinical durability in deep Class II resin composite restorations.

• Journal of the Korean Academy of Esthetic Dentistry
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• v.11 no.2
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• pp.9-13
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• 2002

In the last decade, the replacement of old PFM restorations has been a common dental procedure, especially on the anterior regions. Gingiva conditions in most re-treatment cases are not healthy with the old restorations due to ill-fitting margin, improper tooth reduction and poor oral hygiene. Practitioners must carefully evaluate and manage periabutmental gingiva for final restorations. The role of provisional restoration became a major clinical concern at this point. Well-fabricated provisional restorations with precise-fit margin and proper anatomy are critical for achieving good gingival health. Thus, the key of success in replacing old PFM crown depends on the proper tissue management by precise provisional restorations.

• Proceedings of the Korea Society of Environmental Biology Conference
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• 2001.12a
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• pp.92-92
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• 2001

• Proceedings of the Korea Society of Environmental Biology Conference
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• 2001.12a
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• pp.93-93
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• 2001

• The Journal of Korean Academy of Prosthodontics
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• v.43 no.2
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• pp.158-175
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• 2005

Statement of problem. Every effort has been continually made to obtain objectivity in measuring the longevity of fixed restorations, such as by establishing unified judgement standard for deciding success and adopting statistical method that analyzes the data of successful and failed cases at the same time. In Korea, however desired level of development has not to be made in this field yet. Purpose. This study, adopting California Dental Association (CDA) quality evaluation system, established objective standard for deciding success, and inferred the longevity of fixed restorations and their failure analysis through adopting Kaplan-Meier survival analysis. Material and method. In order to assess the longevity of flxed restorations serviced in Korea and causes of failure, a total of 1109 individuals (aged 15-74, 716 women and 393 men loaded with 2551 unit fixed restorations, and 1934 abutments) who lived in Kyung-In Province were examined and the findings were as follows : Results. 1. Length of service of fixed restorations serviced in Korea was 6.86$\pm$0.15 yr (mean), 5.5 yr (median), and the rate of success was 65.82% in 5 year survival, and 21.15% in 10 year survival. 2. When there was patient's need for replacing old prosthetics, longevity of fixed restorations was 7.51$\pm$0.27 yr (mean), 7 yr (median), and the rate of success was 61.08% in 5 year survival, and 17.57% in 10 year survival. 3. Longevity of fixed restorations was longest in the over-sixty age group(9.21$\pm$0.66) and that of the teen age group(3.39$\pm$0.28) was shortest (p<0.05). 4. Longevity of fixed restorations of women (7.38$\pm$0.18 years) was longer than that of men (6.00$\pm$0.26) (p<0.05). 5. As for the provider factor (such as unlicensed performers, university hospitals, and private clinic), there was no statistically significant difference in longevity of fixed restorations. 6. Defective margin (34.78%). periodontal disease (12.15%), periapical involvement (11.73%), was the most frequent causes of failure and poor esthetics group showed the longest life above all (p<0.05). Actual frequent causes of failure after removing old prosthetics were defective margin, periapical involvement, periodontal disease and uncemented restoration. In 75.67% of the cases, abutment state after removing old prosthetics was good enough for loading another prosthetics. 7. There was found to have statistically significant influence between longevity of single crown (6.35$\pm$0.20 yr) and that of 3 unit fixed restorations (7.60$\pm$0.30 y) (p<0.05). In each case the most frequent cause of failure was defective margin. 8. The number of cantilever pontic, pontic/abutment ratio, oral hygiene status were found to have no statistically significant influence on longevity of fixed restorations in all groups (p>0.05). 9. Longevity of fixed restorations made of non precious metal was longest (9.60$\pm$0.40 yr) semi precious and precious trailing behind(p<0.05). 10. Group function group (37.04%) and partial group function group (44.62%) were predominant in frequency but showed no correlation between them and among different types of occlusal plane and different types of occlusal surface (p>0.05). 11. Longevity of fixed restorations was longest in the centric interference group(9.35$\pm$0.62) (p<0.05) among different types of occlusal interference. Conclusion. We found that longevity of fixed restorations serviced in Korea is affected by age, gender and type of material, and that most frequent cause of failure is defective margin. In order to assess the accurate longevity of axed restorations, unified research design. overcoming inter-observer difference and establishing the objective research items are needed. Furthermore, it is thought that prospective approach through thorough study and regular follow-ups is needed just from the start of research. Nationwide detailed studies on length of service of fixed restorations manufactured in Korea are hoped to be conducted hereafter.