Fatores determinantes na seleção de pinos intra-radiculares
Factors determining of intraradicular post selection
Mazaro, J.V.Q.; Assunção, W.G.; Rocha, E.P.; Zuim, P.R.J.; Gennari Filho, H.
Rev. odontol. UNESP, vol.35, n4, p.223-231, 2006
Resumo
A reconstrução de dentes tratados endodonticamente freqüentemente requer a utilização de pinos e núcleos para o restabelecimento da estética e da função. A seleção de um apropriado sistema pino/núcleo é um dilema clínico, visto as amplas variedades disponíveis. O propósito deste artigo foi discutir os vários fatores que influenciam na seleção do pino e do núcleo, tais como comprimento da raiz, anatomia do dente, largura da raiz, configuração do canal, quantidade de estrutura dental coronária, força de torção, stress, desenvolvimento da pressão hidrostática, design e material do pino, compatibilidade do material, capacidade de adesão e retenção do núcleo, reversibilidade, estética e material da coroa. Assim, baseadas na literatura consultada, algumas recomendações clínicas foram propostas no intuito de orientar o clínico na seleção do sistema pino/núcleo mais adequado para cada caso: 1) conservar o máximo de estrutura dental possível durante o preparo do conduto radicular; 2) pino e núcleo fundido personalizado são recomendados para canais radiculares não-circulares e quando se tem moderada a severa perda de estrutura dentária coronal; 3) pinos pré-fabricados paralelo, passivo, serrilhado e com auto-escape são recomendados para canais circulares pequenos; 4) pinos com fator anti-rotacional devem ser utilizados em situações com canais circulares; 5) adequado selamento apical deve ser mantido sem comprometer o comprimento do pino; 6) mais de um pino deve ser usado para dente curto multirradicular; 7) pinos paralelos passivos são preconizados pela adequada retenção, mas, quando a espessura de dentina apical é mínima, um pino com design paralelo-cônico deve ser indicado; 8) a capacidade retentiva da cabeça do pino facilita a retenção do material para o núcleo; 9) o pino deve assegurar compatibilidade do material, capacidade adesiva, adequada rigidez e compatibilidade estética com a restauração definitiva; 10) reversibilidade, em casos de falha, deve ser considerada; 11) o sistema deve ser de fácil uso e custo viável.
Palavras-chave
Prótese dentária, endodontia, pino, núcleo
Abstract
The reconstruction of teeth treated endodontically frequently requests the use of post and core for the aesthetics and function restoration. The selection of an appropriate post-core system can be a clinical dilemma, seen the wide variety available. The purpose of this article was to discuss the several factors that influence in the selection of the post and core, such as root length, tooth anatomy, root width, canal configuration, amount of coronal tooth structure, torquing force, stresses, development of hidrostatic pressure, post design and material, material compatibility, bonding capacity, core retention, retrievability, esthetics and crown material. As it is, this article can serve as a guide to help the clinical in the selection of the post-core system. This way, based on the consulted literature, some clinical recommendations were proposed with the intention of guiding the clinical in the selection of the post-core system more appropriate for each case, being: 1) conserve as much remaining tooth structure as possible during the post space preparation, 2) custom-cast post and cores are recommended for noncircular root canals and when coronal tooth structure loss is moderate to severe, 3) parallel-sided, passive, serrated and self-venting prefabricated posts are recommended for small circular canals, 4) posts with an antirotational feature should be used in circular canals situations, 5) adequate apical seal must be maintained without compromising the post length, 6) more than one post must be used for multirooted short teeth, 7) passive parallel posts are advocated for adequate retention but when the apical thickness of dentin is minimal, a parallel-tapered combination post design may be preferred, 8) retentive qualities of the post head may facilitate firm retention of core material, 9) the post should ensure material compatibility, bonding ability, adequate rigidity, and esthetic compatibility with permanent restoration, 10) retrievability in the event of failure should be considered, and 11) the system should be easy to use and cost effective.
Keywords
Dental prosthesis, endodontics, Post-core system
References
1. Shillingburg HT, Hobo S, Whitsett L, Brackett S. Fundamentals of fixed prosthodontics.3rd ed. Chicago: Quintessence; 1997.
2. Baraban DJ. The restoration of endodontically treated teeth: an update. J Prosthet Dent. 1988;59:553-8.
3. Sorensen JA, Engelman MJ. Effect of post adaptation on fracture resistance of endodontically treated teeth. J Prosthet Dent. 1990;64:419-24.
4. Holmes DC, Diaz-Arnold AM, Leary JM. Influence of post dimension on stress distribution in dentin. J Prosthet Dent. 1996;75:140-7.
5. Mattison GD, Delivanis PD, Thacker RW Jr, Hassel KJ. Effect of post preparation on the apical seal. J Prosthet Dent. 1984;51:785-9.
6. Kvist T, Rydin E, Reit C. The relative frequency of periapical lesions in teeth with root canal-retained posts. J Endod. 1989;15:578-80.
7. Sen D, Poyrazoglu E, Tuncelli B. The retentive effects of pre-fabricated posts by luting cements J Oral Rehabil. 2004;31:585–9.
8. Nissan J, Dmitry Y, Assif D. The use of reinforced composite resin cement as compensation for reduced post length. J Prosthet Dent. 2001;86:304-8.
9. Standlee JP, Caputo AA, Hanson EC. Retention of endodontic dowels: effect of cement, dowel length, diameter and design. J Prosthet Dent. 1978;39:400-5.
10. Gluskin AH, Radke RA, Frost SL, Watanabe LG. The mandibular incisor: rethinking guidelines for post and core design. J Endod. 1995;21:33-7.
11. Ash M Jr. Wheeler’s dental anatomy, physiology and occlusion. 7th ed. Philadelphia: WB Saunders; 1993.
12. Frommer HH. Radiology for dental auxiliaries. 6th ed. St. Louis: Mosby; 1996.
13. Gutmann JL. The dentin- root complex: anatomic and biologic considerations in restoring endodontically treated teeth. J Prosthet Dent. 1992;67:458-67.
14. Fox, K, Wood, DJ, Youngson, CC. A clinical report of 85 fractured metallic post retained crowns. Int Endod J. 2004;37:561–73.
15. Akkayan B, Gulmez T. Resistance to fracture of endodontically treated teeth restored with different post systems. J Prosthet Dent. 2002;87:431-7.
16. Lloyd PM, Palik JF. The philosophies of dowel diameter preparation: a literature review. J Prosthet Dent. 1993;69:32-6.
17. Stern N, Hirshfeld Z. Principles of preparing endodontically treated teeth for dowel and core restorations. J Prosthet Dent. 1973;30:162-5.
18. Pilo R, Tamse A. Residual dentin thickness in mandibular pre-molars prepared with gates glidden and ParaPost drills. J Prosthet Dent. 2000;83:617-23.
19. Alfredo, E, Garrido Ad, Souza Filho CB, Correr Sobrinho L, Sousa Neto MD. In vitro evaluation of the effect of core diameter for removing radicular post with ultrasound. J Oral Rehabil. 2004;31:590-4.
20. Smith CT, Schuman N. Restoration of endodontically treated teeth: a guide for the restorative dentist. Quintessence Int. 1997;28:457-62.
21. Cohen BI, Pagnillo MK, Condos S, Deutsch AS. Four different core materials measured for fracture strength in combination with five different designs of endodontic posts. J Prosthet Dent. 1996;76:487-95.
22. Saupe WA, Gluskin AH, Radke RA Jr. A comparative study of fracture resistance between morphologic dowel and cores and a resin-reinforced dowel system in the intraradicular restoration of structurally compromised roots. Quintessence Int 1996; 27:483-91.
23. Morgano SM, Milot P. Clinical success of cast metal posts and cores. J Prosthet Dent. 1993;70:11-6.
24. Sorensen JA, Martinoff JT. Intra-coronal reinforcement and coronal coverage: a study of endodontically treated teeth. J Prosthet Dent. 1984;51:780-4.
25. Barkhordar RA, Radke R, Abbasi J. Effect of metal collars on resistance of endodontically treated teeth to root fracture. J Prosthet Dent. 1989;61:676-8.
26. Bergman B, Lundquist P, Sjogren U, Sundquist G. Restorative and endodontic results after treatment with cast posts and cores. J Prosthet Dent. 1989;61:10-5.
27. Sidoli GE, King PA, Setchell DJ. An in vitro evaluation of a carbon fiber based post and core system. J Prosthet Dent. 1997;78:5-9.
28. Stockton L. Factors affecting retention of post system: a literature review. J Prosthet Dent. 1999;81:380-5.
29. Stockton LW, Williams PT. Retention and shear bond strength of two post systems. Oper Dent. 1999;24:210‑6.
30. Pegoraro LF, Pereira JR, Ornelas F, Bonachella WC, Valle AL. Influência da férula em dentes despolpados restaurados com pinos pré-fabricados. In: Anais da 21a Reunião da Sociedade Brasileira de Pesquisa Odontológica – SBPqO; 2004 set. 8-12; Águas de Lindóia (SP). São Paulo: SBPqO; 2004. p. 187.
31. Rosenstiel SR, Land MF, Fujimoto J. Contemporary fixed prosthodontics. 3rd ed. New Delhi: Harcourt; 2001.
32. Burgess JO, Summitt JB, Robbins JW. The resistance to tensile, compression and torsional forces provided by four post systems. J Prosthet Dent. 1992;68:899-903.
33. Cohen BI, Pagnillo MK, Condos S, Deutsch AS. Comparison of the torsional failure for seven endodontic post systems. J Prosthet Dent. 1995;74:350-7.
34. Cohen BI, Pagnillo MK, Newman I, Musikant BL, Deutsch AS. Effect of three bonding systems on torsional resistance of titanium-reinforced composite cores supported by two post designs. J Prosthet Dent. 1999;81:678-83.
35. Peters MC, Poort HW, Farah JW, Craig RC. Stress analysis of a tooth restored with a post and core. J Dent Res. 1983;62:760-3.
36. Fernandes AS, Dessai GS. Factors affecting the fracture resistance of post-core reconstructed teeth: a review. Int J Prosthodont. 2001;4:355-63.
37. Anusavice KJ. Phillip’s science of dental materials.10th ed. New Delhi: Harcourt; 1999.
38. Cohen S, Burns RC. Pathways of the pulp. 8th ed. St. Louis: Mosby; 2002.
39. Johnson JK, Sakamura JS. Dowel form and tensile force. J Prosthet Dent. 1978;40: 645-9.
40. Zmener O. Adaptation of threaded dowels to dentin. J Prosthet Dent. 1980;45:530-5.
41. Ross RS, Nicholls JI, Harrington GW. A comparison of strains generated during placement of five endodontic posts. J Endod. 1991;17:450-6.
42. Cooney JP, Caputo AA, Trabert KC. Retention and stress distribution of tapered end endodontic posts. J Prosthet Dent. 1986;55:540-6.
43. Tilk MA, Lommel TJ, Gerstein H. A study of mandibular and maxillary root widths to determine dowel size. J Endod. 1979;5:79-82.
44. Standlee JP, Caputo AA, Holcomb J, Trabert KC. The retentive and stress distributing properties of a threaded endodontic dowel. J Prosthet Dent. 1980;44:398-404.
45. Cohen BI, Musikant BL, Deutsch AS. Comparison of the photoelastic stress for a split-shank threaded post versus a threaded post. J Prosthodont. 1994;3:53-5.
46. Creuger NH, Mentink AG, Kayser AF. An analysis of durability data on post and core restorations. J Dent. 1993;21:281-4.
47. Fredriksson M, Astback J, Pamenius M, Arvidson K. A retrospective study of 236 patients with teeth restored by carbon fiber-reinforced epoxy resin posts. J Prosthet Dent. 1998; 80:151-7.
48. Assif D, Oren E, Marshak BL, Aviv I. Photoelastic analysis of stress transfer by endodontically treated teeth to the supporting structure using different restorative techniques. J Prosthet Dent. 1989;61:535-43.
49. Asmussen E, Peutzfeldt A, Heitmann T. Stiffness, elastic limit, and strength of newer types of endodontic posts. J Dent. 1999;27:275-8.
50. Ichikawa Y, Akagawa Y, Nikai H, Tsuru H. Tissue compatibility and stability of new zirconia ceramic in vivo. J Prosthet Dent. 1992;68:322-6.
51. Hendlund S-O; Johansson NG; Sjögren G. A retrospective study of pre-fabricated carbon fibre root canal posts. J Oral Rehabil. 2003;30:1036-40.
52. Petersen KB. Longitudinal root fracture due to corrosion of an endodontic post. J Can Dent Assoc. 1971;37:66‑8.
53. Luu KQ, Walker RT. Corrosion of a nonprecious metal post: a case report. Qiuntessence Int 1992;23:389-92.
54. Standlee JP, Caputo AA. Endodontic dowel retention with resinous cement. J Prosthet Dent. 1992;68:913-7.
55. Mannocci E, Ferrari M, Watson TF. Intermittent loading of teeth restored using quartz fiber, carbon-quartz fiber and zirconium dioxide ceramic root canal posts. J Adhes Dent. 1999;1:153-8.
56. Lewis R, Smith BG. A clinical survey of failed post retained crowns. Br Dent J. 1988; 165:95-7.
57. Thayer KE. Fixed prosthodontics. Chicago: Mosby; 1984.
58. Chang WC, Millstein PL. Effect of post design of prefabricated post heads on core materials. J Prosthet Dent. 1993;69:475-82.
59. Coelho Santos G, El-Mowafy O, Henrique Rubo J. Diametral tensile strength of a resin composite core with nonmetallic refabricated posts: an in vitro study. J Prosthet Dent. 2004;91:335-41.
60. Cohen BI, Pagnillo MK, Newman I, Musikant BL, Deutsch AS. Retention of a core material supported by three post head designs. J Prosthet Dent. 2000;83:624‑8.
61. Freedman GA. Esthetic post and core treatment. Dent Clin North Am. 2001;45:103-16.
62. Wilson NHF, Setcos JC, Dummer PMH, Gorman DG, Hopwood WA, Saunders WP, et al. A split-shank prefabricated post system: A critical multidisciplinary review. Quintessence Int. 1997;28:737-43.
63. Vichi A, Ferrari M, Davidson CL. Influence of ceramic and cement thickness on the masking of various types of opaque posts. J Prosthet Dent. 2000;83:412-7.
64. Hochstedler J, Huband M, Poillion C. Porcelain-fusedto- metal post and core: an esthetic alternative. J Dent Technol. 1996;13(8):26-9.
Facebook
Google+
Twitter
LinkedIn
Mendeley
StumbleUpon
CiteULike
Reddit
Email