luting

The tooth preparation for metal ceramic FPDs requires significant amount of tooth structure to be removed, however, in most cases pulp vitality can be maintained in abutments provided prepared abutments are protected after tooth prepara- tion with provisional fixed partial dentures luted with temporary luting cement, which is an essential and key step in successful fixed prosthodontic treatment.3

The selection of permanent luting cement for fixed partial dentures is critical as it has an important role to play in controlling the post cementation sensitivity and success of the final prosthesis.4

Glass Ionomer luting cement which is one of the most commonly used permanent luting agents for cast restorations has a comparatively low initial setting pH at the time of placement and this has been implicated as a cause of post cementation sensitivity5 when the prosthesis is being cemented on teeth with intact pulp vitality.

This study was done to establish that which one of these luting cements offe rs better results in terms of post cementation sensitivity in abutments of fixed partial dentures having vital pulps with full coverage restorations.

TABLE 2: LUTING PROCEDURES FOR THE RESIN LUTING CEMENTS

Botha et al.8 observed no significant difference between immediate and delayed bonding on the shear bond strength of a composite resin luted with a luting resin to abraded dentine.

The film thickness could be lowered by increased magnitude and duration of seating force and elevated by higher viscosity of the luting cement.15 The magni- tude and the duration of force was kept constant in this study but the viscosity could be another variable.

Whereas, Variolink II is a dual curing adhesive luting composite.

Regarding solubility of conventional luting cements, a lot of investigations have been performed by re- searchers.3,4,5,10 Information regarding solubility of lut- ing material is scarce in different pH values of saliva.

On clinical and radiological examination it is usually found that there is recurrent caries on the tooth structure at the circumferential tie area that is where tooth structure, margin of restoration and the luting material are at interface.

Luting materials at circumferential tie area are exposed to oral fluids and any dissolution around the margins of restoration provide stagnation area for the dental plaque.

Other luting materials which have gained more popularity are resin modified glass ionomer cement and resin cement.