• 대한치과보철학회지
• /
• 제37권3호
• /
• pp.375-382
• /
• 1999

The purpose of this article is to present the clinical and laboratory procedures for single tooth restoration using 'Combination Implant Crown'. It is cemented on implant abutment and that abutment is screw-retained over implant body. This type of implant restorations has the advantages of cement-retained restoration while being antirotational and retrievable. And, more esthetic and functional result can be achieved by minimizing the size of access hole. The results were as follows : 1. Preparation of abutment below the cuff line should be avoided 2. Axial reduction of implant abutment should not be excessive because it may weaken the abutment 3. More esthetical and functional occlusal surface was achieved with a minimal access hole which is slightly larger than the diameter of hex driver to enable future total retrievability. 4. Combination Implant Crown has the advantages of both the cement-retained and screw-retained type implant restoration. 5. Cementation between implant crown and abutment reduces screw loosening through even force distribution

• 구강회복응용과학지
• /
• 제20권2호
• /
• pp.135-141
• /
• 2004

Statement of problem: Arrangement and angulation of clinical crown is very important for esthetic restoration in the upper anterior dentition. However, there was no clinical criteria to mesial angulation of the crown for Korean. Purpose: This study was undertaken to estimate the mesial angulation of the crown of the anterior teeth and the Oh's E-triangle made of the inter-pupillary line and the mesial inclination lines of the canines. Material and Method: 270 portraits of Korean were used for this study. The mesial angulation of the upper anterior teeth and the relationship of the inter-pupillary line and the mesial inclination lines of the canines were measured with the tools of PhotoShop software on the scanned images. Results: The angulation between the clinical crowns having a same name in the upper anterior dentition were $3.6^{\circ}$ between the central incisors, $8.6^{\circ}$ between the lateral incisors, and $13.6^{\circ}$ between the canines. There was no significance according to occupation and gender( P > 0.05). The ratio of height to base line of Oh's E-triangle was 4.47. 81.6% of the subjects showed the mesial inclination line of the canine passed by mesial border area of pupil. Conclusion: These data for Korean would be useful clinically to give the esthetic arrangement and to make the contour of upper anterior teeth.

• 대한치과의사협회지
• /
• 제57권11호
• /
• pp.679-688
• /
• 2019

A 8-year-old patient presented with a crown-root fracture of the maxillary right central incisor with an oblique subgingival fracture line. A multidisciplinary treatment approach including endodontic treatment, surgical extraction and intraalveolar repositioning was used to gain sufficient crown length of the fractured maxillary incisor. The coronally repositioned maxillary right central incisor was stabilized by a resin wire splint. Apexification using MTA was performed. Resin core and direct resin restoration(Cl IV) on fractured teeth was built up. Clinical and radiographic follow-up of the maxillary right central incisor after 36 months showed no signs of root resorption or pathology and acceptable aesthetics and functions were maintained. Surgical extrusion can be considered as a good treatment modality for young patients.

• The Journal of Advanced Prosthodontics
• /
• 제8권6호
• /
• pp.494-503
• /
• 2016

PURPOSE. The aim of this study was to compare the efficacies of two-implant splinting (2-IS) and single-implant restoration (1-IR) in the first and second molar regions over a mean functional loading period (FLP) of 40 months, and to propose the appropriate clinical considerations for the splinting technique. MATERIALS AND METHODS. The following clinical factors were examined in the 1-IR and 2-IS groups based on the total hospital records of the patients: sex, mean age, implant location, FLP, bone grafting, clinical crown-implant ratio, crown height space, and horizontal distance. The mechanical complications [i.e., screw loosening (SL), screw fracture, crown fracture, and repeated SL] and biological complications [i.e., peri-implant mucositis (PM) and peri-implantitis (PI)] were also evaluated for each patient. In analysis of two groups, the chi-square test and Student's t-test were used to identify the relationship between clinical factors and complication rates. The optimal cutoff value for the FLP based on complications was evaluated using receiver operating characteristics analysis. RESULTS. In total, 234 patients with 408 implants that had been placed during 2005 - 2014 were investigated. The incident rates of SL (P<.001), PM (P=.002), and PI (P=.046) differed significantly between the 1-IR and 2-IS groups. The FLP was the only meaningful clinical factor for mechanical and biological complication rates in 2-IS. CONCLUSION. The mechanical complication rates were lower for 2-IS than for 1-IR, while the biological complication rates were higher for 2-IS. FLP of 39.80 and 46.57 months were the reference follow-up periods for preventing biological and mechanical complications, respectively.

• 대한치과교정학회지
• /
• 제26권6호
• /
• pp.657-666
• /
• 1996

Orthopantomogram is commonly used to evaluate root parallelism. "Good parallelism" between roots is widely accepted as one of the guidelines of a successful orthodontic treatment. In case there was a large angle between crown axis and root axis, and if we valued only the position of crown in establishing occlusal relationship without considering of the situation of root, the problem of root arrangement between adjacent teeth would be occurred. The estimate of root parallelism in mesiodistal direction before and after orthodontic treatment must be emphasized. The intent of this study was to determine the clinical importance and correlation of the angle between crown axis and root axis. Orthopantomograms of 105 orthodontic patients being treated in Yonsei university were used in this study. Twenty-eight teeth in both maxilla and mandible were selected and analyzed quantitively to evaluate the angle between crown axis and root axis, and obtain the correlationship among the individual teeth. The results are as follows: 1. Among the teeth presenting normal distribution, the maxillary right canine showed the largest mean value( $5.73{\pm}4.42^{\circ}$), which was composed of the crown-root angles, and the mandibular left lateral incisor showed the smallest mean value( $0.60{\pm}3.76^{\circ}$). 2. The crown-root angles of the maxillary incisors and the first molars, and the mandibular central incisors and the first molars didn't show normal distribution and the ranges of these angles were dispersed. 3. Significant differences were present between the crown axis and the root axis except for lower first premolars. (p<0.05) 4. No significant difference was present for the crown-root angle between right and left side, (p<0.05) 5. No significant difference was present for the crown-root angle between male and female except for lower left first premolar. (p<0.05) 6. In the upper right quadrant, significant correlations were present between crown-root angles of the central incisor and lateral incisor, lateral incisor and canine. In the upper left quadrant, significant correlations were present between crown-root angles of the central incisor and lateral incisor. In the lower right quadrant, significant correlations were present between crown-root angles of the central incisor and lateral incisor, first molar and second molar. In the lower left quadrant, significant correlations were present between crown-root angles of the central incisor and lateral incisor, lateral incisor and canine, first molar and second molar. (p<0.05)

• 대한치과의사협회지
• /
• 제29권11호통권270호
• /
• pp.826-827
• /
• 1991

• 대한치과의사협회지
• /
• 제41권11호통권414호
• /
• pp.761-767
• /
• 2003

• 대한치과의사협회지
• /
• 제29권9호통권268호
• /
• pp.656-656
• /
• 1991

• 대한치과의사협회지
• /
• 제29권10호통권269호
• /
• pp.740-741
• /
• 1991

• 대한치과보철학회:학술대회논문집
• /
• 대한치과보철학회 2003년도 춘계학술대회 및 제1회 한일 공동 학술대회
• /
• pp.72-72
• /
• 2003