• The Journal of Korean Academy of Prosthodontics
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• v.62 no.2
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• pp.131-139
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• 2024

In a edentulous patient, various methods can be employed for prosthetic treatment using implants, such as implant-supported fixed prostheses, overdentures, hybrid prostheses, and implant assisted removable partial denture. In this case, in a patient with moderate to severe chronic periodontitis requiring full arch extractions, implants were strategically placed using computer-guided surgery. In the maxilla, due to inadequate bone quality and quantity leading to insufficient initial stability, delayed loading was implemented, and interim prosthesis was used during the osseointegration period. In the mandible, stable initial stability was achieved, allowing for immediate loading to reduce patient discomfort. Primary stability is considered the most crucial factor for obtaining immediate loading, so a thorough clinical and radiological evaluation of the remaining alveolar bone quantity and quality must be conducted before surgery.

• Journal of Dental Rehabilitation and Applied Science
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• v.34 no.4
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• pp.280-289
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• 2018

Purpose: The purpose of this randomized clinical trial is to determine whether implant length and the crown-to-implant (C/I) ratio influence implant stability and peri-implant marginal bone loss (MBL). Materials and Methods: 46 patients with single tooth missing in the posterior molar region of the mandible were included in this study. 19 implants (CMI IS-III $active^{(R)}$ long implant) of 5.0 mm diameter and 10 mm length were installed for the control group, while 27 implants (CMI IS-III $active^{(R)}$ short implant) of 5.5 mm diameter and 6.6, 7.3 or 8.5 mm length were placed for the experimental group. Each implant was inserted and immediately loaded using the digitally pre-fabricated surgical template and provisional restoration. The CAD-CAM monolithic zirconia crown was fabricated at 3 months after the surgery as a definitive restoration. The ISQ value and the MBL was measured at 48 weeks after the surgery. The correlation between the C/I ratio, MBL, and secondary implant stability was analyzed. Results: Successful results in terms of ISQ and MBL were achieved with both groups. There was no significant difference between the groups in terms of ISQ values and MBL at 48 weeks after the surgery (P > 0.05). No significant correlation was found between the C/I ratio and secondary stability as well as the C/I ratio and the MBL (P > 0.05). Conclusion: The influence of C/I ratio in both groups was not shown on the stability nor the marginal bone loss in implants supporting single crown of the mandible. Short implant could be a preferable alternative option in the reduced bone height mandible under the limited condition despite its higher C/I ratio.

• The Journal of Korean Academy of Prosthodontics
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• v.51 no.2
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• pp.107-112
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• 2013

Complications increases when crown height space is excessive and one should be careful of choosing type of fixed prosthesis in case crown height space is over 12 mm. In this condition, tooth seems to be longer, therefore, it is needed to use gingival shade in aesthetically important area for fixed prosthesis. In this case, fixed prosthesis which has inappropriate maintenance and hygiene could hold food, plaque, calculus, thus increase incidence of inflammation and infection. Moreover, it could lead to chronic inflammation and infection and in that case surgical improvement could be necessary. In present case report, gingival inflammation and swelling developed around prosthesis after having made it considering articulation and aesthetic view in patient who had excessive crown height space. Finding out that design of prosthesis is a factor to make it hard to maintain oral hygiene, a temporary prosthesis which has enough interproximal space and proper emergence profile was fabricated. After two months of observation, significant abnormal symptoms are not found and oral reconstruction is performed using fixed prosthesis with zircornia infrastructure and porcelain build-up based on convenient self hygiene design. Through serial treatment, inappropriate soft tissue response is not observed and satisfactory result in functional aspect comes out.

• Journal of Periodontal and Implant Science
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• v.33 no.4
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• pp.563-571
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• 2003

One of the central components of periodontal therapy is the improvement of esthetics. The presence and appearance of interdental papillae plays an important role of periodontal esthetics. The aim of the present study was to investigate how immediate provisional restoration preserve the shape of interdental papilla around the extraction socket and the width of bucco-lingual of gingiva. Another aim was to investigate the change in the interdental papilla and the amount of vertical bone fill of a extraction socket in relation to the interdental alveolar bone levels adjacent the alveolar socket. A total of 19 patients (11 male, 8 female, mean age of 50.57${\pm}$8.16), who visited the Department of Periodontology, Pusan National University and had more than one anterior tooth scheduled to be extracted due to an advanced periodontal disease were included in the present study. After initial periodontal therapy, the extracted teeth were reshaped of the root and placed into the socket followed by splinting with adjacent teeth with self-curing resin. The width of hucco-lingual of gingiva and interdental papilla height were measured at baseline, 1, 3, 6, 9 and 12 month and the periapical radiographic examination were taken at baseline, 6 and 12month following the extraction. The amount of vertical bone fill in the extraction socket were calculated. At 12 months following the extraction, the changes in mesial and distal interdental papilla and the width of bucco-lingual showed -1.06${\pm}$0.48mm, -0.844${\pm}$0.50mm, -1.50${\pm}$0.96m, relatively. The positional change in the interproximal papillae was significantly associated with the interdental bone level adjacent to the extraction socket(p=0.028). The higher the interproximal bone level adjacent the extraction socket, the greater the amount of bone fill in the extraction socket(p<0.001). In conclusion, it was thought that immediate provisional restoration could minimize the loss of the width of bucco-lingual and interproximal papillae around the extraction socket. In addition, the higher the interproximal bone level adjacent the extraction socket, the greater the amount of bone fill and the smaller the reduction of papillary height around the extraction socket.

• Journal of Dental Rehabilitation and Applied Science
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• v.34 no.2
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• pp.89-96
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• 2018

Purpose: The aim of this study was to evaluate the effect of delayed time, surface treatment, and repair materials on repair of bis-acryl composite resin through comparison of shear bond strength and to evaluate the utility of bis-acryl composite resin repair using polymethyl methacrylate resin. Materials and Methods: A total of 90 bis-acryl composite resin specimens were fabricated and classified into 9 test groups, each of 10 pieces according to delayed time, surface treatment and repair material. The shear bond strength of each specimen was measured using a universal testing machine immediately after fabrication and analyzed using a statistical analysis program (IBM SPSS statistics 20). After the shear bond strength measurement, the fracture surface of the specimen was observed. Results: The highest shear bond strength ($17.54{\pm}3.14MPa$) was observed in the experimental group bonded immediately with a light-curing flowable composite resin using a bonding agent. Conclusion: When repairing bis-acryl composite resin, it is necessary to consider whether to remake according to the delayed time. For effective repair, it is desirable to consider appropriate materials and surface treatment methods according to the site or purpose of use.

• The Journal of Korean Academy of Prosthodontics
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• v.44 no.5
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• pp.503-513
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• 2006

Statement of the problem: The cold-cured resins used in fabrication of the provisional crown and fixed partial dentures could cause pulpal damage by heat generated during exothermic polymerization reactions. Purpose: In this in vitro study investigates the how external conditions such as material of the matrix, thickness of the matrix and thickness of dentin affect the temperature of the tooth during polymerization reaction of the cold-cured resins. Material and methods : To measure the temperature of the resin, metal die was maintained to the temperature of $37^{\circ}C$ with water bath to simulate the temperature of thetooth and thermocouple was placed in the center of the metal die. Acrylic pipe was cut in height of 1, 2, 3, 6, 10 mm and placed on the metal die and mixed resin was pored in the acrylic pipe As the resin polymerized temperature was recorded with the thermometer. Temperature of the resin using matrix was recorded by using the individual tray relieved in different thickness 2, 5, 7, 10 mm. The material of the matrix was irreversible hydrocolloid impression material, vinyl polysilloxane impression material and vacuum-formed template Temperature rise of the resin using different thickness of tooth section was record ed by placing tooth section on the metal die and placing resin over the tooth section. Results : Conclusion : 1. Temperature rise increased as the thickness of the resin increased but there was no significant differences over 3 mm thickness of the resin. 2. The lowest temperature rise was showed in irreversible hydrocolloid impression material and vinyl polysilloxane impression material vacuum-formed template as in orders. 3, Temperature rise of the resin decreased regardless of the thickness of the matrix when vinyl polysilloxane impression material was used as the matrix. 4 When irreversible hydrocolloid impression material was used as matrix, the temperature rise of the resin decreased as the thickness of the matrix increased and there was no temperature rise when thickness of the matrix reached 10 mm, 5. The temperature rise of the resin did not decreased when Polypropylene vacuum-formed template was used as the matrix. 6, The temperature of the resin increased as the thickness of the dentin decreased.

• Restorative Dentistry and Endodontics
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• v.28 no.1
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• pp.1-10
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• 2003

This study investigated the influence of IRM on marginal microleakage of 5th generation adhesives. Class V cavities with gingival margins in dentin were prepared on both buccal and lingual surfaces of 60 extract-ed human molar teeth. Prepared teeth were randomly divided into six groups. Group 1 and 4 received no temporary restoration with IRM. Group 2 and 5 were covered with IRM mixed at P/L ratio(10g/1g). Group 3 and 6 were covered with IRM mixed at P/L ratio(10g/2g). The temporary restorations were removed mechanically with an ultrasonic scaler after one-week storage in distilled water. The cavities were restored using one of two adhesives and composites ; Single Bond/Filtek Z 250(Croup 1, 2 and 3), UniFil Bond/UniFil F(Group 4, 5 and 6). Following one day storage in distilled water, the restored teeth were thermocycled for 500 cycles(between $5^{\circ}C{\;}and{\;}55^{\circ}C$) and immersed in 2 % methylene blue for dye penetration testing. The results were analysed using Kruskal-Wallis Test, Mann-Whitney and Wilcoxon signed ranked test at a significance level of 0.05. The results of this study were as follows 1. Ranking of mean microleakage scores at the enamel margins was Group 10.05) 4. At the dentin margins, the microleakage of the group not pretreated with IRM was lower than that of the group pretreated with IRM. And the microleakage of UniFil Bond was lower than that of Single Bond. 5. Compared with microleakages between the enamel and dentin margins of each groups, Group 1, 2, 3, 4, 5 and 6 at dentin margin were higher microleakage than those at enamel margin. There were significant difference between enamel and dentin microleakage of Group 2 and 3(p<0.05).

• The Journal of Korean Academy of Prosthodontics
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• v.39 no.5
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• pp.514-525
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• 2001

The purpose of this study was to compare the marginal fit of provisional restorations by differentiating the removal time and setting temperature during resin polymerization. After mixing autopolymerizing methyl methacrylate resin, the material was placed in a preformed resin shell crown. The crown was seated on a die with 1mm shoulder margin. Crowns were removed after 3, 4, 5, 6 minutes and polymerization was continued under the following conditions : $25^{\circ}C$ air, $30^{\circ}C,\;40^{\circ}C,\;50^{\circ}C,\;60^{\circ}C,\;70^{\circ}C$ water. After polymerization. the crown was sectioned. The marginal & occlusal discrepancies were measured. The mean marginal discrelpancies at 3 minutes, 4 minutes, 5 minutes and 6 minutes of removing time were $96.6{\mu}m.\;84.6{\mu}m,\;86.7{\mu}m$ and $105.6{\mu}m$. The mean occlusal discrepancies at 3 minutes, 4 minutes, 5 minutes and 6 minutes of removing time were $106.7{\mu}m,\;89.3{\mu}m,\;98.6{\mu}m$ and $127.7{\mu}m$. There was significant difference between 4 minutes group and 6 minutes group in occlusal discrepancies. The mean marginal & occlusal discrepancies for crowns polymerized in $25^{\circ}C$ air were $98.2{\mu}m$ and $124.1{\mu}m$. The crowns polymerized in $50^{\circ}C$ water demonstrated the smallest marginal & occlusal. discrepancies. The mean value of marginal & occlusal discrepancies in $50^{\circ}C$ water were $73.1{\mu}m$ and $77.5{\mu}m$. These values were smaller than that of $25^{\circ}C$ air. There were significant differences in the occlusal discrepancies between $25^{\circ}C$ air and water conditions of $50^{\circ}C$ water (${\alpha}=0.05$) but. no significant difference in marginal discrepancies. There was no significant difference in the interaction between time and temperature. 4 minutes waiting time & $50^{\circ}C$ water polymerizing condition produces the best fit at the margin of the provisional crown.

• Journal of Dental Rehabilitation and Applied Science
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• v.37 no.3
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• pp.157-170
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• 2021

Loss of posterior bite support might cause unstable occlusal relationship and when the mandible slides forward in the centric or habitual occlusion, excessive load is applied to the anterior region followed by causing the occlusal plane to collapse or leading to a decrease in occlusal vertical dimension. In addition, disorder of temporomandibular joint function may occur. The inter-dental arch discrepancy causes a mismatch in the vertical and horizontal overlap of the anterior and posterior regions. The deep bite in the anterior region and the scissor bite in the posterior region cause unstable occlusal contact and insufficient occlusal contact area. This report was to rehabilitate a patient with above-mentioned complex problems. Physiologic adaptation to increased vertical dimension and new occlusal plane were evaluated using provisional prostheses, and definitive prostheses was fabricated using cross-mounting technique. Stable occlusion, harmonious teeth overlap and adequate occlusal plane were established, so functionally and aesthetically satisfactory results are obtained.

• The Journal of Korean Academy of Prosthodontics
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• v.57 no.3
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• pp.245-253
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• 2019

Orthognathic surgery of skeletal Class III malocclusion improves oral function and facial appearance. The greater amount of skeletal discrepancy, the greater amount of teeth movement required for decompensation, and this often causes pathological changes in periodontal tissue especially in lower anterior dentition. We made a Top-Down treatment plan with personalized analysis using Face Hunter, Plane System and ARCUS Digma II, in order to resolve severe mobility and cross-bite of lower anterior teeth for 49-year-old female patient who had undergone orthognathic surgery 20 years ago due to skeletal Class III malocclusion and mandibular prognathism. Lower anterior teeth were extracted and alveoloplasty was done. After healing of the wound, immediate loading was conducted immediately after implant placement. Final restorations were fabricated Zirconia using CAD/CAM, and inserted intraorally screw-retained type. During 6-month follow-up, no abnormal episodes of restorations were observed, and obtained satisfactorily both of functional and esthetic outcomes.