RETENTION OF COMPLEX AMALGAM RESTORATIONS USING SELF-THREADING PINS, AMALGAPINS, AND AMALGAMBOND

Purpose: To compare the shear fracture resistance of complex amalgam r estorations retained by four regular TMS pins, four amalgapins, Amalga mbond, or four amalgapins in conjunction with Amalgambond. Materials a nd Methods: Sixty maxillary molars free of caries were mounted in acry lic resin and the occlusal surfaces were ground flat to within 2 mm of the CEJ. The specimens were randomly divided into four groups of 15 t eeth. Each group provided one of the four different methods of resista nce. Dispersalloy was condensed into the prepared specimens. The speci mens were adjusted to provide 4 mm height of amalgam. After 1000 therm ocycles, the specimens were loaded at a 45 degrees angle to the occlus al surface at a crosshead speed of 1 mm/second. Results: Statistical a nalysis revealed that Amalgambond, four amalgapins, and four amalgapin s in conjunction with Amalgambond provided more resistance to shear fo rce than four regular TMS pins.