Evaluation of occlusal rest seat depth in bicuspids: an experimental study

  • José Carlos Reis Campos Faculdade de Medicina Dentária da Universidade do Porto
  • André Ricardo Correia Faculdade de Medicina Dentária da Universidade do Porto
  • Maria Helena Figueiral Professor Auxiliar Convidado Departamento de Prótese Removível Faculdade de Medicina Dentária da Universidade do Porto
  • Patrícia Fonseca Faculdade de Medicina Dentária da Universidade do Porto
  • Filomena Rodrigues Médica Dentista. Clínica Privada no Porto.
  • Fernando Morais Branco Faculdade de Medicina Dentária da Universidade do Porto
Keywords: Removable partial denture, dental abutments, bicuspid, dental enamel, dentin,

Abstract

Objective: Since premolars may be used as abutment teeth of removable partial dentures, the aim of this study was to evaluate the depth of occlusal rest seats in premolars and its relation with dentin and enamel. Methods: Twenty-nine premolar teeth (extracted for orthodontic reasons) were randomly selected from patients at a University Clinic. The mesio-distal and buccal-lingual dimensions were measured. Rest seats were prepared with round burs (1.0-1.5 mm) in premolar mesial and distal fossae. Rest seats were cut with a microtome and observed in a scanning electron microscope. Tooth abrasion was also evaluated using the Gourdon indice. Results: Significant differences were observed in the enamel thickness before and after rest seat preparations. Maximum enamel thickness in the deepest part of the rest seat was 625 μm in distal and 500 μm in mesial. In more than 50% of the teeth, dentin was reached. Almost 80% were not abraded. Conclusion: In most situations it is not possible to prepare a rest seat with 1.5 mm depth only in enamel. In teeth not abraded it is possible to prepare rest seats with 1.0 mm without reaching dentin. There are significant differences between enamel thickness in distal and mesial, before and after rest seat preparation.

Author Biographies

José Carlos Reis Campos, Faculdade de Medicina Dentária da Universidade do Porto
Professor Auxiliar com Agregação na Faculdade de Medicina Dentária da Universidade do Porto. Departamento de Prótese Removível.
André Ricardo Correia, Faculdade de Medicina Dentária da Universidade do Porto
Serviço de Anatomia Faculdade de Medicina Dentária da Universidade do Porto
Maria Helena Figueiral, Professor Auxiliar Convidado Departamento de Prótese Removível Faculdade de Medicina Dentária da Universidade do Porto
Professora Associada com Agregação na Faculdade de Medicina Dentária da Universidade do Porto. Departamento de Prótese Removível.
Patrícia Fonseca, Faculdade de Medicina Dentária da Universidade do Porto
Professora Auxiliar Convidada de Prótese Removível na Faculdade de Medicina Dentária da Universidade do Porto. Departamento de Prótese Removível.
Filomena Rodrigues, Médica Dentista. Clínica Privada no Porto.
Médica Dentista. Clínica Privada no Porto.
Fernando Morais Branco, Faculdade de Medicina Dentária da Universidade do Porto
Professor Catedrático da Faculdade de Medicina Dentária da Universidade do Porto.

References

The glossary of prosthodontic terms. J Prosthet Dent. 2005;94:10-92.

McCracken WL. Contemporary partial denture designs. 1958. J Prosthet Dent. 2004 Nov;92(5):409-17.

Borel JC, Schittly J, Exbrayat J. Elementos que intervienen en la constitución de una prótesis parcial removible metálica. Manual de Protesis Parcial Removible. Barcelona: Masson S.A.; 2002.

Munhoz LO, Vellini-Ferreira F, Cotrim-Ferreira FA, Inês Ferreira R. Evaluation of proximal enamel thickness and crown measurements in maxillary first premolars. Braz J Oral Sci. 2012;11:30-5.

Feeney R, Zermeno J, Reid D, Nakashima S, Sano H, Bahar A, et al. Enamel thickness in Asian human canines and premolars. Anthropological Science. 2010;118:191-8.

Bates J, Neill D, Priskel H. Abutment preparation for removable partial dentures. Restoration of the partially dentate mouth. Chicago: Quintessence Publishing Co; 1984. p. 259-69.

Kratochvil FJ, Thompson WD, Caputo AA. Photoelastic analysis of stress patterns on teeth and bone with attachment retainers for removable partial dentures. J Prosthet Dent. 1981;46:21-8.

Lescher MJ, Dimicoli G, Borel JC. Preparation of occlusal rests on lower molars. Odontologia. 1988;9:139-45.

Rudd RW, Bange AA, Rudd KD, Montalvo R. Preparing teeth to receive a removable partial denture. J Prosthet Dent. 1999;82:536-49.

Davenport JC, Basker RM, Heath JR, Ralph JP, Glantz PO, Hammond P. Tooth preparation. Br Dent J. 2001;190:288-94.

Luk NK, Wu VH, Liang BM, Chen YM, Yip KH, Smales RJ. Mathematical analysis of occlusal rest design for cast removable partial dentures. Eur J Prosthodont Restor Dent. 2007;15:29-32.

Carr AB, Brown DT. McCracken’s Removable Partial Prosthodontics. 12. ed. St Louis, Missouri: Elsevier Mosby; 2011.

Sato Y, Shindoi N, Koretake K, Hosokawa R. The effect of occlusal rest size and shape on yield strength. J Prosthet Dent. 2003;89:503-7.

Darling A. The pathology and prevention of caries. Br Dent J. 1959;107: 287-96.

Anderson J, Bates J. The cobalt-chromium partial denture. Br Dent J. 1959;107:57-62.

Bergman B, Hugoson A, Olsson CO. Caries and periodontal status in patients fitted with removable partial dentures. J Clin Periodontol. 1977;4:134-46.

Schwalm CA, Smith DE, Erickson JD. A clinical study of patients 1 to 2 years after placement of removable partial dentures. J Prosthet Dent. 1977;38:380-91.

Benson D, Spolsky VW. A clinical evaluation of removable partial dentures with I-bar retainers. Part I. J Prosthet Dent. 1979;41:246-54.

Vermeulen AH, Keltjens HM, van’t Hof MA, Kayser AF. Ten-year evaluation of removable partial dentures: survival rates based on retreatment, not wearing and replacement. J Prosthet Dent. 1996;76:267-72.

Owall B, Budtz-Jorgensen E, Davenport J, Mushimoto E, Palmqvist S, Renner R, et al. Removable partial denture design: a need to focus on hygienic principles? Int J Prosthodont. 2002;15:371-8.

Rice JA, Lynch CD, McAndrew R, Milward PJ. Tooth preparation for rest seats for cobalt-chromium removable partial dentures completed by general dental practitioners. J Oral Rehabil. 2011;38:72-8.

Glann G, Appleby R. Mouth preparation for removable partial dentures. J Prosthet Dent. 1960;10:698-706.

Perry C. A philosophy of partial denture design. J Prosthet Dent. 1956;6:775-84.

Seiden A. Occlusal rests and rest seats. J Prosthet Dent. 1958;8:431-40.

Miller E, Grasso J. Removable partial prosthodontics. 2. ed. Baltimore: Williams and Wilkins; 1981.

Gourdon A, Wada A. Mise au point d’un indice d’abrasion. Cah Prothese. 1983;43:115-22.

Carr AB, Brown DT. Rests and rest seats. In: Carr AB, Brown DT, editors. McCracken’s Removable Partial Prosthodontics. 12. ed. St Louis, Missouri: Elsevier Mosby; 2011. p. 56-66.

Gapido CG, Kobayashi H, Miyakawa O, Kohno S. Fatigue resistance of cast occlusal rests using Co-Cr and Ag-Pd-Cu-Au alloys. J Prosthet Dent. 2003;90:261-9.

Jones RM, Goodacre CJ, Brown DT, Munoz CA, Rake PC. Dentin exposure and decay incidence when removable partial denture rest seats are prepared in tooth structure. Int J Prosthodont. 1992;5:227-36.

Culwick PF, Howell PG, Faigenblum MJ. The size of occlusal rest seats prepared for removable partial dentures. Br Dent J. 2000;189:318-22.

Zanetti AL, Mengar MA, Novelli MD, Lagana DC. Thickness of the remaining enamel after the preparation of cingulum rest seats on maxillary canines. J Prosthet Dent. 1998;80:319-22.

Published
2013-11-03
Section
Original Article