Comparison of push-out bond strength of post according to cement application methods = 시멘트 도포 방법에 따른 포스트의 push-out 접착 강도 비교

다국어 초록 (Multilingual Abstract)

Objectives: The aim of this study was to compare the push-out bond strengths of resin cement/fiber post systems to post space dentin using different application methods of resin cement.
Materials and Methods: Thirty extracted human premolars were selected and randomly divided into 3 groups according to the technique used to place the cement into root canal: using lentulo-spiral instrument (group Lentulo), applying the cement onto the post surface (group Direct), and injecting the material using a specific elongation tip (group Elongation tip). After shaping and filling of the root canal, post space was drilled using Rely-X post drill. Rely-X fiber post was seated using Rely-X Unicem and resin cement was light polymerized. The root specimens were embedded in an acrylic resin and the specimens were sectioned perpendicularly to the long axis using a low-speed saw. Three slices per each root containing cross-sections of coronal, middle and apical part of the bonded fiber posts were obtained by sectioning. The push-out bond strength was measured using Universal Testing Machine. Specimens after bond failure were examined using operating microscope to evaluate the failure modes.
Results: Push-out bond strengths were statistically influenced by the root regions. Group using the elongation tip showed significantly higher bond strength than other ways. Most failures occurred at the cement/dentin interface or in a mixed mode.
Conclusions: The use of an elongation tip seems to reduce the number of imperfections within the selfadhesive cement interface compared to the techniques such as direct applying with the post and lentulospiral technique.

국문 초록 (Abstract)

연구목적: 이 연구의 목적은 레진 시멘트의 포스트 공간 내 적용 방법에 따른 포스트의 push-out접착 강도를 비교하는 것이었다.
연구 재료 및 방법: 30개의 발거된 하악소구치를 사용하여 시멘트의 적용 방법에 따라 세 그룹으로 나누었는데 lentulo-spiral을 이용하여 포스트 공간 내에 레진 시멘트를 적용하는 그룹 (group Lentulo), 직접 포스트 표면에 레진 시멘트를 도포하는 그룹 (group Direct), elongation tip을 이용하여 포스트 공간 내에 레진 시멘트를 적용하는 그룹 (group Elongation tip)으로 나누었다. 근관을 성형, 충전한 뒤 Rely-X post drill을 사용하여 포스트 공간을 형성하였고, Rely-X fiber post를 Rely-X Unicem 적용하여 광중합 하였다. 시편을 아크릴릭 레진에 포매 하고 저속 절단기로 치아 장축에 수직으로 절단하여, 하나의 치아에서 치관부, 중앙, 근단부의 세 개의 시편을 얻었다. 절단한 시편을 Universal Testing Machine으로 push-out 접착 강도를 측정하였다. 접착 실패가 일어난 시편을 수술용 현미경 하에서 관찰하여 그 실패 양상을 결정하였다.
결과: 치근의 위치에 따른 push-out 접착 강도는 유의한 차이를 보였으며, 전용의 elongation tip을 사용한 그룹이 가장 높은 push-out 접착 강도를 나타냈다.
결론: 레진 시멘트를 포스트에 직접 적용하거나 lentulo-spiral을 사용하는 기존의 방법에 비해 elongation tip을 사용하는 것이 self-adhesive 계면의 결함을 줄이고 근관치료한 치아의 수복 성공율을 높일 수 있을 것으로 생각된다.

참고문헌 (Reference)

• 1 김문홍, "레진시멘트의 중합방법이 포스트의 결합강도와 접착계면에 미치는 영향" 대한치과보존학회 34 (34): 103-112, 2009
• 2 김진우, "레진 시멘트를 이용한 레진 파이버 강화 레진포스트의치근 상아질에 대한 미세인장결합강도" 대한치과보존학회 28 (28): 80-88, 2003
• 3 이현아, "다양한 레진시멘트로 합착한 섬유포스트의 결합강도 비교" 대한치과보존학회 33 (33): 499-506, 2008
• 4 Testori T, "Vertical root fractures in endodontically treated teeth: a clinical survey of 36 cases" 19 : 87-91, 1993
• 5 Faria-e-Silva AL, "The effects of different luting procedures in the push-out bond strength of fibre posts to the root canal" 27 : 1653-1666, 2008
• 6 D’Arcangelo C, "The effect of resin cement film thickness on the pullout strength of a fiber reinforced post system" 98 : 193-198, 2007
• 7 Goracci C, "The contribution of friction to the dislocation resistance of bonded fiber posts" 31 : 608-612, 2005
• 8 Goracci C, "The adhesion between fiber posts and root canal walls: comparison between microtensile and push-out bond strengths measurements" 112 : 353-361, 2004
• 9 Bergman B, "Restorative and endodontic results after treatment with cast posts and cores" 6 : 10-15, 1989
• 10 Schwartz RS, "Post placement and restoration of endodontically treated teeth: a literature review" 30 : 289-301, 2004
• 11 Axelsson P, "On the prevention of caries and periodontal disease. Results of a 15-year longitudinal study in adults" 18 : 182-189, 1991
• 12 Watzke R, "Interface homogeneity of adhesively luted glass fiber posts" 24 : 1512-1517, 2008
• 13 Akgungor G, "Influence of dentin bonding agents and polymerization modes on the bond strength between translucent fiber posts and three dentin regions within a post space" 95 : 368-378, 2006
• 14 Gaston BA, "Evaluation of regional bond strength of resin cement to endodontic surfaces" 27 : 321-324, 2001
• 15 Ferrari M, "Efficacy of a selfcuring adhesive/resin cement system on luting glass-fiber posts into root canals: an SEM investigation" 14 : 543-549, 2001
• 16 Bitter K, "Effects of luting agent and thermocycling on bond strengths to root canal dentine" 39 : 809-818, 2006
• 17 D’Arcangelo C, "Effect of Application Technique of Luting Agent on the Retention of Three Types of Fiber-reinforced Post Systems" 33 : 1378-1382, 2007
• 18 Foxton RM, "Bonding of photo and dual cure adhesives to root canal dentin" 28 : 543-551, 2003
• 19 De Munck J, "Bonding of an autoadhesive luting material to enamel and dentin" 20 : 963-971, 2004
• 20 Kurtz JS, "Bond strengths of toothcolored posts, effect of sealer, dentin adhesive, and root region" 16 : 31-36, 2003
• 21 D’Arcangelo C, "An evaluation of luting agent application technique effect on fibre post retention" 36 : 235-240, 2008
• 22 Boschian Pest L, "Adhesive post-endodontic restorations with fiber posts: push-out tests and SEM observations" 18 : 596-602, 2002
• 23 Foxton RM, "Adhesion to root canal dentine using one and two-step adhesives with dual-cure composite core materials" 32 : 97-104, 2005
• 24 Cardoso PE, "Adhesion testing with the microtensile method: effects of dental substrate and adhesive system on bond strength measurement" 4 : 291-297, 2002