Figure 16 Mean shear bond strength after 1800 thermo cycles between 5 and 55 °C – pooled data from 6 practitioners Figure 16 shows the mean shear bond strength from the pooled data of all six practitioners. It is obvious that the adhesives under test worked very well in the hands of practitioners. Summary of bond strength data for direct procedures It could be proven that Prime&Bond XP shows bond strength data that could not be surpassed by any other adhesive tested reaches this high level of performance with a simple application technique in which active rubbing or scrubbing is not needed is compatible with either LED or QTH curing lights shows very high shear fatigue limit works very well in the hands of practitioners Adhesion for indirect procedures Prime&Bond XP on its own can be used for luting indirect restorations if purely light curing materials are used. In the case where the clinician wishes to use dual or chemical curing resin cements, Prime&Bond XP is mixed with SCA – this mixture is compatible to the chemistry used for such cements. If Calibra® resin luting cement (DENTSPLY) is used light curing of the adhesive layer before seating the restoration could be omitted or it is ensured that parts of the luting interface not being exposed sufficiently to light are well bonded, respectively. Shear Bond Strength to enamel and dentin for indirect procedures (DENTSPLY DeTrey, ) Practitioners are concerned that light curing the adhesive before seating an indirect restoration may interfere with the proper fit. For this reason, manufacturers of systems having rather thick consistency bonding agents explicitly instruct not to cure the adhesive layer in these situations.
Marginal quality provided by Prime&Bond XP in dentin was better than one of the two tested adhesives (Figure 34). Summary of data on marginal quality of direct restorations Prime&Bond XP not only offers a very good seal of the margins in enamel and dentin but provides an exceptional seal of dentin, too. Marginal integrity of luted ceramic inlays Marginal integrity with and without curing the adhesive (, ) Practitioners very often hesitate to light cure the adhesive when luting indirect restorations because of possible interference of pooled and cured adhesive with the fit while seating the restoration for luting. For systems including high viscous bonding materials (e.g. Heliobond) the respective manufacturer recommends not to cure the adhesive because of this reason. It was evaluated whether curing the adhesive layer in the case of Prime&Bond XP had any influence (Prime&Bond XP SCA (LC)). Figure 35 Perfect margins of adhesively ceramic inlays It could be demonstrated that Prime&Bond XP and SCA when using Calibra classic as cement performs equally well with and without being light cured before seating the restoration. Micro-Morphology In order to illustrate and understand the interaction between adhesive and tooth substance specimens were investigated using FESEM, TEM and light microscopy. FESEM and TEM investigation Since etching of dentin with phosphoric acid was introduced one focus of research has been the question whether the demineralized collagen network can be infiltrated