Effects of surface conditioning on the retentiveness of titanium crowns over short implant abutments.
OBJECTIVE
The integrity and retention of cemented restorations over implant abutments is difficult to achieve when the axial wall height of the abutment is short.


OBJECTIVE
: To compare the effect of different surface conditions on the retentiveness of titanium crowns cemented over short (3 mm) ITI solid abutments using 2 types of cement. Surface pretreatment included sandblasting, silicoating, and application of alloy primer.


METHODS
Forty-eight ITI implants and solid abutments 5.5 mm in height were divided into six groups. The axial height of abutments in group I was unaltered to serve as a control. The remaining abutments in (groups II-VI) were reduced to a 3-mm height. Groups I and II were luted with ZnPO4 cement without any surface pretreatment. In groups III and IV, the fit surface of the castings and solid abutments were sandblasted, before luting, with ZnPO4 or Panavia 21, respectively. In group V castings and abutments were sandblasted, pretreated with Siloc Bond, and luted with Panavia 21. In group VI castings and abutments were sandblasted, pretreated with alloy primer, and luted with Panavia 21. Crown retention was measured using a universal testing machine after 1 week of storage in water at 37 degrees C.


RESULTS
Analysis of variance revealed a highly significant difference among the groups. Sandblasted castings and abutments pretreated with alloy primer or Siloc Bond before luting with Paravia 21 resin cement exhibited the greatest retentive strength (P < 0.05). Castings luted with zinc phosphate over short ITI solid abutment exhibited the lowest retention (P < 0.05).


CONCLUSIONS
The retention of titanium castings luted over ITI solid abutments was influenced by axial height, surface texture, surface pretreatment, and type of cement. Phosphoric alloy primer is more effective and less technique sensitive than the Siloc Bond with regard to retention enhancement of titanium castings over short ITI solid abutment.
Sadig
Walid M
WM
Department of Prosthetic Dental Science, King Saud University, Faculty of Dentistry, Riyadh, Saudi Arabia. walidsadig@hotmail.com
Al Harbi
Mohammed W
MW
D003442:Crowns; D015921:Dental Implants; D003764:Dental Materials / Q000737:chemistry; D017268:Dental Prosthesis Retention / Q000379:methods*; D019232:Dental Restoration Failure; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry
D015921:Dental Implants; D003764:Dental Materials; D014025:Titanium