Marginal fidelity of crowns fabricated from six proprietary provisional materials

An Investigation into the Integrity of Fit of Provisional Crowns made over a Dental Implant Analogue Using Two Current Proprietary Provisional Crown Materials Compared to a Proprietary 'Snap On' Provisional Core

“…Tjan et al [9] reported marginal discrepancies of 40.1 μm for Bis-GMA acryl resin composite and 23.6 μm for isobutyl methacrylate. The same group of investigators in a more recent study reported an improved marginal fit for provisional crowns made from Bis-GMA composite resin provisional materials [8] using again the same methodology. Bis-GMA acryl resin composite provisional material resulted in 22 μm of marginal opening, and a visible light cured provisional material 29 μm.…”

“…Numerous studies appear in the dental literature comparing the marginal fit of provisional restorations made from different types of materials [8][9][10]17] and different techniques [18][19][20][21] as well as the effect of environment's temperature [22] and storage conditions [23]. Dental implant companies, on the other hand, have all tried to make the temporization phase of treatment more predictable and many have produced stock templates for their own implant systems.…”

“…However, Bis-GMA acryl resin composites have become a popular alternative choice due to their ease of use. Research has shown Bis-GMA acryl resin composite to provide some advantages in physical properties including low polymerization shrinkage [7] and good marginal adaptation [8][9][10] low exothermic reaction [11,12] minimal pupil and soft tissue irritation [13], good surface hardness [14], and increased color stability [2,12].…”

Crowns and other extra-coronal restorations: Provisional restorations

“…4b) produce less heat and shrinkage during polymerisation than other resins, resulting in a better marginal fit. 5 Despite being reasonably strong they are brittle in thin section and difficult to add to. Aesthetically they are reasonable, but few shades are available and they stain easily if the unpolymerised surface layer is not removed which may be accomplished with alcohol and polishing.…”

Effect of water temperature and duration of immersion on the marginal accuracy of provisional crowns

“…Therefore provisional crowns should be removed from the prepared tooth after initial polymerization and allowed to complete polymerization outside the mouth. [4][5][6] Few authors have reported that placing the provisional crown during polymerization in water enhances the polymerization efficiency and reduces the monomer content, which results in better provisional restorations. 5,7 Literature has also shown that marginal fit and strength of provisional restoration varies when polymerization takes place at different water temperatures.…”