Primary stability of a hybrid self-tapping implant compared to a cylindrical non-self-tapping implant with respect to drilling protocols in an ex vivo model.
BACKGROUND
Modifications of implant design have been intending to improve primary stability. However, little is known about investigation of a hybrid self-tapping implant on primary stability.


OBJECTIVE
The aims of this study were to evaluate the primary stability of two hybrid self-tapping implants compared to one cylindrical non-self-tapping implant, and to elucidate the relevance of drilling protocols on primary stability in an ex vivo model.


METHODS
Two types of hybrid self-tapping implants (Straumann® Bone Level implant [BL], Straumann® Tapered Effect implant [TE]) and one type of cylindrical non-self-tapping implant (Straumann® Standard Plus implant [SP]) were investigated in the study. In porcine iliac cancellous bones, 10 implants each were inserted either using standard drilling or under-dimensioned drilling protocol. The evaluation of implant-bone interface stability was carried out by records of maximum insertion torque, the Periotest® (Siemens, Bensheim, Germany), the resonance frequency analysis (RFA), and the push-out test.


RESULTS
In each drilling group, the maximum insertion torque values of BL and TE were significantly higher than SP (p=.014 and p=.047, respectively). In each group, the Periotest values of TE were significantly lower than SP (p=.036 and p=.033, respectively). The Periotest values of BL and TE were significantly lower in the group of under-dimensioned drilling than standard drilling (p=.002 and p=.02, respectively). In the RFA, no statistical significances were found in implants between two groups and between implants in each group. In each group, the push-out values of BL and TE were significantly higher than SP (p=.006 and p=.049, respectively).


CONCLUSIONS
Hybrid self-tapping implants could achieve a high primary stability which predicts them for use in low-density bone. However, there is still a debate to clarify the influence of under-dimensioned drilling on primary stability.
Toyoshima
Takeshi
T
Department of Oral and Maxillofacial Surgery, Johannes Gutenberg University Mainz, Augustusplatz 2, Mainz, Germany. takesea@dent.kyushu-u.ac.jp
Wagner
Wilfried
W
Klein
Marcus Oliver
MO
Stender
Elmar
E
Wieland
Marco
M
Al-Nawas
Bilal
B
D000818:Animals; D003758:Dental Implantation, Endosseous / Q000379:methods*; D015921:Dental Implants; D017267:Dental Prosthesis Design; D017268:Dental Prosthesis Retention; D003799:Dental Stress Analysis; D013516:Oral Surgical Procedures, Preprosthetic / Q000295:instrumentation / Q000379:methods*; D013552:Swine; D019415:Torque
D015921:Dental Implants