The retention difference between cobalt chromium and zirconia coping in different angulations on telescopic overdenture

Kevin Christopher Kawilarang(1), Heriyanti Amalia Kusuma(2), Murti Indrastuti(3*)

(1) Haigi Dental, Karangawaru, Tegalrejo, Yogyakarta Prosthodontics Specialist Study Program, Faculty of Dentistry, Universitas Gadjah Mada, Yogyakarta
(2) Department of Prosthodontics, Faculty of Dentistry, Universitas Gadjah Mada, Yogyakarta
(3) Department of Prosthodontics, Faculty of Dentistry, Universitas Gadjah Mada, Yogyakarta
(*) Corresponding Author


Telescopic overdenture is one type of removable denture that uses dual coping system that consists of primary and secondary coping. Retention of telescopic overdenture is obtained from the friction between primary and secondary coping, which is mainly influenced by the type of material and coping angulation. The purpose of this study is to determine the retention differences between CoCr and zirconia coping with 0°, 1°, and 2° angulations.
Twenty four pairs of telescopic overdenture coping samples with 6 mm length were divided into 6 groups (n = 4), CoCr 0°, CoCr 1°, CoCr 2°, zirconia 0°, zirconia 1°, and zirconia 2°. Measurement of retention between coping is done by pull-off test using universal testing machine (UTM) and data were analyzed by two way ANOVA. The results showed that the largest average retention was found in zirconia coping with 0° angulation group (22.48 N), while the smallest average retention was found in CoCr coping with 2° angulation group (10.28 N). Two way ANOVA revealed that there were significant differences among groups (p<0.05). LSD tests showed that there were significant differences among all of groups. This study concludes that zirconia coping has higher retention than CoCr coping and coping with 0° angulation has the highest retention.


angulation; cobalt-chronium; telescopic overdenture; zirkonia

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1. Zarb G, Hobkrik JA, Eckert SE, Jacob RF. Prosthodontic treatment for edentulous
patients, ed. 13. Mosby: Elsevier; 2012.

2. Singh K, Gupta N. Telescopic denture – a treatment modality for minimizing the conventional removable complete denture problems: a case report. Journal of Clinical and
Diagnostic Research. 2012; 6(6): 1112-1116.

3. Bibinagar R, Anam C, Mamidi P, Saxena A, Rathinam J. Telescopic overdenture. Journal
of Orofacial Research. 1970; 3(1): 57-62.

4. Mishra R, Shivrayan A, Jain S, Mehta S. Fabrication of bar‑retained tooth‑supported
mandibularoverdenture. Int J Oral Health Sci. 2014; 4: 37-41. doi: 10.4103/22316027.151624

5. Wagner C, Stock V, Merk S, Schmidlin P, Roos M, Eichberger M, Stawarczyk B. Retention
load of telescopic crowns with different taper angles between cobalt-chromium and
polyetheretherketon made with three different manufacturing processes examined by pulloff
test. J Prosthodont. 2018; 27(2): 162-168. doi: 10.1111/jopr.12482

6. Kim EC, Kim MK, Leesungbok R, Lee SW, Ahn SJ. Co-Cr dental alloys induces cytotoxicity
and inflammatory responses via activation of Nrf2/antioxidant signaling pathways in human
gingival fibroblasts and osteoblasts. Dent Mater. 2016; 32(11): 1394-1405.
doi: 10.1016/

7. Merk S, Wagner C, Stock V, Eichberger M, Schmidlin P, Roos M, Stawarczyk B.
Retention load values of telescopic crowns made of Y-TZP and CoCr with Y-TZP
secondary crowns: impact of different taper angles. Materials (Basel). 2016; 9(5): 354.
doi: 10.3390/ma9050354

8. Sax C, Hammerle C, Sailer I. 10-year clinical outcomes of fixed dental prostheses with
zirconia frameworks. Int J Comput Dent. 2011; 14(3): 183–202.

9. Dabrowa T, Dobrowoloska A, Wieleba W. The role of friction in the mechanism of retaining
the partial removable dentures with double crown system. Acta Bioeng Biomech. 2013;
15(4): 43-48.

10. Zafiropoulos G, Rebbe J, Thielen U, Deli G, Beaumont C, Hoffmann O. 2010, Zirconia
removable telescopic dentures retained on teeth or implants for maxilla rehabilitation. Three-year observation of three cases. J Oral Implantol. 2010; 36(6): 455-465. doi: 10.1563/

11. Guven MC, Tuna M, Bozdag E, Ozturk GN, Bayraktar G. Comparison of retention forces
with various fabrication methods and material in double crowns. J Adv Prosthodont. 2017;
9(4): 308-314. doi: 10.4047/jap.2017.9.4.308

12. Bevington PR, Robinson DK. Data reduction and error analysis for the phisical science
Third Edition. NewYork: McGrow-Hill; 2003.

13. Pietruski JK, Sajewicz E, Sudnik J, Pietruska MD. Retention force assessment in conical
crowns in different material combinations. Acta Bioeng Biomech. 2013; 15(1): 35-42.


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