Avaliação Comparativa da Perda de Retenção de Attachments do Tipo Barra/Clipes Usados em Overdentures
Comparative evaluation of retention loss of bar/clips attachments for Overdentures
Freitas, R.; Vaz, L.G.; Pedreira, A.P.R.V.
Rev. odontol. UNESP, vol.32, n2, p.113-118, 2003
Resumo
Objetivou-se avaliar a perda de retenção sofrida por dois modelos de Attachments para Overdentures do tipo barra/clipe, marcas Conexão® Sistemas de Prótese e Sterngold Implamed® do Brasil, durante 5 anos de uso simulado, utilizando-se um e 2 clipes sobre a barra. As barras foram fixadas a 2 análogos Standard posicionados sobre um modelo de aço. Os clipes foram capturados sob 40 bases de overdentures e submetidos à ciclagem mecânica na máquina de ensaios mecânicos Material Test System 810, velocidade de deslocamento vertical de 2 mm/min, freqüência 2 Hz, amplitude 0,3 mm e 5.400 ciclos. O teste estático de resistência ao deslocamento foi realizado em intervalos de tempo pré-estabelecidos (inicial, 6 meses, um a 5 anos) entre os períodos de ensaio dinâmico realizados na mesma máquina. Utilizou-se Análise de Variância e Teste de Tukey, p < 0,05. Ambos os grupos perderam retenção ao longo do experimento, sem diferença estatisticamente significante entre os intervalos de tempo analisados. A resistência média inicial à remoção variou de 6,4 N (Sterngold Implamed/2 clipes) a 55,2 N (Conexão/2 clipes), e a final entre 1,9 N (Sterngold Implamed/1 clipe) a 42,6 N (Conexão/2 clipes). Nenhum attachment sofreu perda total de sua retentividade.
Palavras-chave
Sobredentaduras, encaixes, retenção
Abstract
The aim of this study was to evaluate the retention loss of two plastis bar-clip overdenture attachments systems from Conexão® and Sterngold Implamed® do Brazil, throughout five years of simulated function with one and two clips upon the bar. The bars of both systems were fixed on two Standard analogues, upon a steel laboratory cast. Forty overdentures saddles were made. Each bar-clip assembly was subjected to 5,400 insertion and removal cycles in the Material Test System 810, with a 2 mm/min cross-speed, 2 Hz frequency and 0.3 mm amplitude. The strenght dislodgement static test was performed in database, six months and one to five years, among the dinamic test perfomed in the same machine. Data were subjected to Analysis of Variance and Tukey test, p < 0.05. Retention decreased over the course of consecutive pulls for all the attachments, with no statistically significant diference among the periods analysed. The initial strenght dislodgement resistance average varied from 6.4 N (Sterngold Implamed®/2 clips) to 55.2 N (Conexão®/2 clips) and the final average varied from 1.9 N (Sterngold Implamed®/1 clip) to 42.6 N (Conexão®/2 clips). All the attachments showed residual retentiveness at the final of the test.
Keywords
Overdentures, attachments, retention
Referências
1. BONACHELA, W. C.; ROSSETI, P. H. O. Overdentures – das raízes aos implantes osseointegrados. Planejamentos, tendências e inovações. São Paulo: Ed. Santos,
2002. 216 p.
2. BREEDING, L. C. et al. The effect of simulated function on the retention of bar-clip retained removable prostheses. J. Prosthet. Dent., St. Louis, v.75, n.5, p.570-573, May 1996.
3. BURNS, D. R. et al. Prospective clinical evaluation of mandibular implant overdentures. Part I – retention stability and tissue response. J. Prosthet. Dent., St. Louis, v.73, n.4, p.354-363, Apr. 1995.
4. DAVIDOFF, S. R.; DAVIS, R. P. The ERA® implant supported overdenture. Compend. Contin. Educ. Dent., Jamesburg, v.16, p.512-520, 1995.
5. DOLDER, E. Bar dentures. Int. Dent. J., London, v.14, n.2, p. 249-251, 1964.
6. EPSTEIN, D. D. et al. Comparison of the retentive properties of six prefabricated post overdenture attachment system. J. Prosthet. Dent., St. Louis, v. 82, n. 5, p.579-583, Nov. 1999.
7. GAMBORENA, J. I. et al. Retention of ERA direct overdenture attachment before and after fatigue loading. Int. J. Prosthodont., Lombard, v. 10, n. 2, p.123-130, Mar./Apr. 1997.
8. GEERTMAN, M. E. Denture satisfaction in a comparative study of implant retained mandibular overdentures: a randomized clinical trial. Int. J. Oral Maxillofac. Implants, Lombard, v.11, n.1, p.194-200, Jan./Feb. 1996.
9. MERICSKE-STERN, R. D. et al. Management of the edentulous patient. Clin. Oral Implants Res., Copenhagen, v.11, suppl. 1, p.108-125, 2000.
10. PETROPOULOS, V. C. et al. Comparison of retention and release periods for implants overdenture attachments. Int. J. Oral Maxillofac. Implants, Lombard, v.12, n.2, p.176-185, Mar./Apr. 1997.
11. SETZ, D. M. et al. Retention of prefabricated attachments for implant stabilized overdentures in the edentulous mandible: an in vitro study. J. Prosthet. Dent., St. Louis, v. 80, n. 3, p. 323-329, Sept. 1998.
12. WALTON, J. N.; RUSE, N. D. In vitro changes in clips and bars used to retain implant overdentures. J. Prosthet. Dent., St. Louis, v. 74, p. 482-486, Nov. 1995.
13. WILLIAMS, B. H. et al. Retention of maxillary implant overdenture bars of different designs. J. Prosthet. Dent., St. Louis, v. 86, n.6, p. 603-607, Dec. 2001.
14. WRIGH, P. S. et al. The effects of prefabricated bar design on the success of overdentures stabilized by implants. Int. J. Oral Maxillofac. Implants, Lombard, v. 10, n.1, p. 79-87, Jan./Feb. 1995.
15. ZITZMANN, N. U.; MARINELLO C. P. A review of clinical and technical considerations for fixed and removable implant protheses in the edentulous mandible. Int. J. Prosthodont., Lombard, v. 15, n. 1, p. 65-72, Jan./Feb. 2002.
Facebook
Google+
Twitter
LinkedIn
Mendeley
StumbleUpon
CiteULike
Reddit
Email