The effect of 3 torque delivery systems on gold screw preload at the gold cylinder-abutment screw joint.

PURPOSE This study measured the gold screw preload at the gold cylinder-abutment screw joint interface obtained by 3 torque delivery systems. MATERIALS AND METHODS Using a precalibrated, strain-gauged standard abutment as the load cell, 3 torque delivery systems tested were shown to have significant differences in gold screw preload when a gold cylinder was attached. RESULTS Mean preloads measured were 291.2 N for hand torque drivers set at 10 Ncm, 340.3 N for electronic torque controllers at low setting/10 Ncm, 384.4 N for electronic torque controllers at high setting/10 Ncm; and 140.8 N for hand-tightening with a prosthetic slot screwdriver. Significant differences in screw preload were also found between operators using a hand torque driver. DISCUSSION Hand-tightening delivered insufficient preload and cannot be recommended for final gold screw tightening. Different electronic torque controller units set at 10 Ncm induced mean gold screw preloads that ranged from 264.1 N to as high as 501.2 N. CONCLUSION Electronic torque controllers should be regularly recalibrated to ensure optimal output.

[1]  S. Palmqvist,et al.  Complications, supplementary treatment, and maintenance in edentulous arches with implant-supported fixed prostheses. , 1990, The International journal of prosthodontics.

[2]  E A Patterson,et al.  Theoretical analysis of the fatigue life of fixture screws in osseointegrated dental implants. , 1992, The International journal of oral & maxillofacial implants.

[3]  D van Steenberghe,et al.  A study of 589 consecutive implants supporting complete fixed prostheses. Part II: Prosthetic aspects. , 1992, The Journal of prosthetic dentistry.

[4]  J I Nicholls,et al.  Accuracy of the implant torque wrench following time in clinical service. , 1997, The International journal of prosthodontics.

[5]  B Rangert,et al.  Forces and moments on Branemark implants. , 1989, The International journal of oral & maxillofacial implants.

[6]  T Jemt,et al.  Loads and designs of screw joints for single crowns supported by osseointegrated implants. , 1992, The International journal of oral & maxillofacial implants.

[7]  G D Stafford,et al.  On clinical loading of osseointegrated implants. A methodological and clinical study. , 1993, Clinical oral implants research.

[8]  S G Vermilyea,et al.  Torque generated by handheld screwdrivers and mechanical torquing devices for osseointegrated implants. , 1994, The International journal of oral & maxillofacial implants.

[9]  W R Laney,et al.  Tissue-integrated prosthesis complications. , 1993, The International journal of oral & maxillofacial implants.

[10]  G E Carlsson,et al.  Prosthodontic complications in osseointegrated dental implant treatment. , 1994, The International journal of oral & maxillofacial implants.

[11]  J. Brunski,et al.  The role of screws in implant systems , 1994 .

[12]  J I Nicholls,et al.  Three-dimensional analysis of the casting accuracy of one-piece, osseointegrated implant-retained prostheses. , 1993, The International journal of prosthodontics.

[13]  Carlsson Ge,et al.  Rehabilitation of the edentulous mandible with a tissue-integrated fixed prosthesis: a six-year longitudinal study. , 1987 .

[14]  M I MacEntee,et al.  Problems with prostheses on implants: a retrospective study. , 1994, The Journal of prosthetic dentistry.

[15]  T. Jemt.  Failures and complications in 391 consecutively inserted fixed prostheses supported by Brånemark implants in edentulous jaws: a study of treatment from the time of prosthesis placement to the first annual checkup. , 1992, The International journal of oral & maxillofacial implants.

[16]  B Rangert,et al.  Mechanical aspects of a Brånemark implant connected to a natural tooth: an in vitro study. , 1991, The International journal of oral & maxillofacial implants.

[17]  O C Tebrock,et al.  A measurement of torque values obtained with hand-held drivers in a simulated clinical setting. , 1993, Journal of prosthodontics : official journal of the American College of Prosthodontists.

[18]  D L Dixon,et al.  Torque required to loosen single-tooth implant abutment screws before and after simulated function. , 1993, The International journal of prosthodontics.

[19]  A Schmitt,et al.  The longitudinal clinical effectiveness of osseointegrated dental implants: the Toronto study. Part III: Problems and complications encountered. , 1990, The Journal of prosthetic dentistry.

[20]  E A Patterson,et al.  Tightening characteristics for screwed joints in osseointegrated dental implants. , 1994, The Journal of prosthetic dentistry.

[21]  P I Brånemark,et al.  A 15-year study of osseointegrated implants in the treatment of the edentulous jaw. , 1981, International journal of oral surgery.

[22]  J. Brunski,et al.  Effects of fabrication, finishing, and polishing procedures on preload in prostheses using conventional "gold' and plastic cylinders. , 1996, The International journal of oral & maxillofacial implants.

[23]  P. Glantz,et al.  Rehabilitation of the edentulous mandible with a tissue-integrated fixed prosthesis: a six-year longitudinal study. , 1987, Quintessence international.