근관와동형태에 따른 근관치료된 하악절치의 파절강도 = THE INFLUENCE OF DIFFERENT ACCESS CAVITY DESIGNS ON THE FRACTURE STRENGTH IN ENDODONTICALLY TREATED MANDIBULAR ANTERIOR TEETH

다국어 초록 (Multilingual Abstract)

Straight access cavity design allows the operator to locate all canals, helps in proper cleaning and shaping, ultimately facilitates the obturation of the canal system. However, change in the fracture strength according to the access cavity designs was not clearly demonstrated yet. The purpose of this study was to determine the influence of different access cavity designs on the fracture strength in endodontically treated mandibular anterior teeth.
Recently extracted mandibular anterior teeth that have no caries, cervical abrasion, and fracture were divided into three groups (Group 1 : conventional lingual access cavity, Group 2 : straight access cavity, Group 3 : extended straight access cavity) according to the cavity designs. After conventional endodontic treatment, cavities were filled with resin core material. Compressive loads parallel to the long axis of the teeth were applied at a crosshead speed of 2mm/min until the fracture occurred. The fracture strength analyzed with ANOVA and the Scheffe test at the 95% confidence level.
The results of this study were as follows :
1. The mean fracture strength decrease in following sequence Group 1 (558.90 ± 77.40 N), Group 2 (494.07 ± 123.98 N) and Group 3 (267.33 ± 27.02 N).
2. There was significant difference between Group 3 and other groups (P = 0.00).
Considering advantage of direct access to apical third and results of this study, straight access cavity is recommended for access cavity form of the mandibular anterior teeth

참고문헌 (Reference)

1 "하악 절치의 근관계에 관한 연구" 27 (27): 432-439, 2002

2 "anatomic and biologic considerations in restoring endodontically treated teeth" 458-467, 1992

3 "Straight-line endodontic access to anterior teeth" 59 (59): 418-419, 1985

4 "Site comparisons of dentine collagen cross-links from extracted human teeth" 38 (38): 541-546, 1993

5 "Root fracture in endodontically treated teeth related to post selection and crown design" 68 (68): 428-435, 1992

6 "Restoration of endodontically treated posterior teeth" 2 (2): 374-375, 1976

7 "Reduction in tooth stiffness as a result of endodontic and restorative procedures" 15 (15): 512-516, 1989

8 "Moisture content of vital vs endodontically treated teeth" 10 (10): 91-93, 1994

9 "Mechanical effectiveness of root canal irrigation" 9 (9): 475-479, 1983

10 "Incidence of two root canals in human mandibular incisor" 38 (38): 122-126, 1974

11 "Ideal endodontic access in mandibular incisors" 25 (25): 206-207, 1999

12 "Fracture strength and survival rate of endodontically treated maxillary incisors with approximal cavities after restoration with different post and core systems: an in-vitro study." 26 (26): 427-433, 2001

13 "Ferrule design and fracture resistance of endodontically treated teeth" 63 (63): 529-536, 1990

14 "Endodontic access to maxillary lateral incisors" 52 (52): 443-445, 1981

15 "Endodontic Therapy" Mosby 104-163, 2003

16 "Effect of access cavity location and design on degree and distribution of instrumented root canal surface in maxillary anterior teeth" 34 (34): 176-183, 2001

17 "Determination of the moisture content of vital and pulpless teeth" 34 (34): 661-670, 1972