Tensile bond strength between paediatric prefabricated zirconia crowns and primary maxillary incisors when using various types of luting cements: an in vitro study

PURPOSE

There is limited evidence regarding the most appropriate type of luting cement for paediatric prefabricated zirconia crowns (PZCs) in primary maxillary incisors. The retention of PZCs is dependent on the bond strength of luting cement between PZCs and primary maxillary incisors. The aim of this study was to evaluate the tensile bond strengths between PZCs and primary maxillary incisors with different types of luting cements.

METHODS

Thirty freshly extracted human primary maxillary incisors were prepared and randomly divided into three groups corresponding to three luting cements: bioactive cement, resin cement, and resin-modified glass ionomer cement (RMGIC), and then restored with PZCs. Tensile bond strengths were evaluated by a universal testing machine. The results were analysed using one-way ANOVA with Tukey's post-hoc test (p < 0.05).

RESULTS

The means of the tensile bond strengths were 1.43 ± 0.85 MPa, 0.91 ± 0.63 MPa, and 0.56 ± 0.39 MPa for the bioactive cement, resin cement, and RMGIC groups, respectively. A significant difference in tensile bond strength was observed between the bioactive cement and the RMGIC group (p < 0.05) but there was no significant difference in tensile bond strength between the resin cement group and the others.

CONCLUSION

Types of luting cement influenced the tensile bond strength between PZCs and primary maxillary incisors. The bioactive cement showed higher tensile bond strength than the resin cement and RMGIC.

The use of aesthetic paediatric full coverage restorations among paediatric dental practitioners: an international survey

Despite the recent growing evidence in support of prefabricated zirconia crown use as a successful option in managing grossly carious anterior and posterior primary teeth, the use of such crowns remains controversial within the paediatric dental profession. This study aims to assess the use of aesthetic full coverage paediatric restorations among paediatric dentists worldwide, with emphasis on aesthetic prefabricated zirconia crowns. This was an online cross-sectional survey questionnaire study comprising of 38 multiple-choice questions disseminated worldwide through the contact lists of national, regional and international paediatric dental organisations and social media platforms. The survey was completed by 556 respondents thus achieving power, with 391 (70.3%) females and 165 (29.7%) males. The respondents were from 55 different countries spread across six continents. The use of aesthetic full coverage restorations was reported by 80% (n = 444) of the respondents. For restoring anterior teeth, participants mainly used either composite strip crowns (94.4%, n = 419) or zirconia crowns (73.6%, n = 327), while those who used aesthetic crowns for restoring posterior teeth mainly used zirconia crowns (68.2%, n = 303). Within the limitations of this study, the results have shown a wide use of full coverage aesthetic restorations, including the use of zirconia crowns, of primary teeth within this international sample of practicing dentists.