J Adv Prosthodont.  2021 Dec;13(6):343-350. 10.4047/jap.2021.13.6.343.

Rotational tolerances of a titanium abutment in the as-received condition and after screw tightening in a conical implant connection

• Prisco R
• Troiano G
• Laino L
• Zhurakivska K

• KMID: 2524029
• DOI: http://doi.org/10.4047/jap.2021.13.6.343

Abstract

PURPOSE
The success of an implant-prosthetic rehabilitation is influenced by good implant health and an excellent implant-prosthetic coupling. The stability of implant-prosthetic connection is influenced by the rotational tolerance between anti-rotational features on the implant and those on the prosthetic component. The aim of this study is to investigate the rotational tolerance of a conical connection implant system and its titanium abutment counterpart, in various conditions. MATERIAL AND METHODS 10 preparable titanium abutments, having zero-degree angulation (MegaGen, Daegu, Korea) with an internal 5-degree conical connection, and 10 implants (MegaGen, Daegu, Korea) were used. Rotational tolerance between the connection of implant and titanium abutments was measured through the use of a tridimensional optics measuring system (Quick Scope QS250Z, Mitutoyo, Kawasaki, Japan) in the as-received condition (Time 0), after securing with a titanium screw tightening at 35 Ncm (Time 1), after tightening 4 times at 35 Ncm (Time 2), after tightening one more time at 45 Ncm (Time 3), and after tightening another 4 times at 45 Ncm (Time 4).
RESULTS
The group “Time 0” had the lowest values of rotational freedom (0.22 ± 0.76 degrees), followed by the group Time 1 (0.46 ± 0.83 degrees), the group Time 2 (1.01 ± 0.20 degrees), the group Time 3 (1.30 ± 0.85 degrees), and the group Time 4 (1.49 ± 0.17 degrees).
CONCLUSION
The rotational tolerance of a conical connection is low in the “as received” condition but increases with repetitive tightening and with application of a torque greater than 35 Ncm.

Keyword

Rotational tolerance; Conical connection; Rotational freedom; Implant prosthesis