Stepp, Paula & Morrow, Brian & Wells, Martha & Tipton, David & Garcia-Godoy, Franklin. (2018). Microleakage of Cements in Prefabricated Zirconia Crowns. Pediatric dentistry. 40. 136-139.

PURPOSE

The purpose of this study was to investigate and compare microleakage of prefabricated posterior NuSmile® ZR and EZCrowns when cemented with BioCem and Ketac Cem dental cements.

METHODS

Forty extracted permanent teeth (n equals 10 per group) were fitted for either NuSmile or EZCrowns prefabricated posterior zirconia crowns and cemented with BioCem or Ketac Cem, for a total of four groups. Crowned teeth were placed in Dulbecco's Phosphate Buffered Saline solution at 37 degrees Celsius for 24 hours. Teeth were thermocycled between five degrees Celsius and 55 degrees Celsius for 6,000 cycles, stained with two percent basic fuchsin, sectioned, and visually inspected for microleakage utilizing stereomicroscopy on a four-point scale. Data were statistically analyzed using one-way analysis of variance, SNK (P<.05).

RESULTS

All samples in this study had microleakage. NuSmile® ZR crowns demonstrated significantly less microleakage when cemented with BioCem and compared to Ketac Cem (P=.002). NuSmile® ZR cemented with BioCem had significantly less microleakage compared to EZ-Crowns with Ketac Cem (P=.002).

CONCLUSION

In this in vitro investigation, BioCem cement had significantly less microleakage in zirconia pre-fabricated crowns compared to Ketac Cem, and NuSmile® ZR crowns cemented with BioCem resulted in significantly less microleakage than EZ-Crowns cemented with Ketac Cem.

Stepp, Paula & Morrow, Brian & Wells, Martha & Tipton, David & Garcia-Godoy, Franklin. (2018). Microleakage of Cements in Prefabricated Zirconia Crowns. Pediatric dentistry. 40. 136-139.

PURPOSE

To assess and compare the microleakage extent between preformed metal crowns (PMCs), preveneered PMCs and zirconia crowns using different adhesive luting cements.

METHODS

Thirty-six primary first molars were divided into three groups (n = 12) each prepared to receive different crowns(PMCs, preveneered PMCs, or zirconia crowns). Each group was further sub-grouped (n = 4) according to the luting cement (resin cement, resin modified glass ionomer cement, or glass ionomer cement). After cementation, the teeth were thermocycled, placed in 0.5% basic fuchsin, and sectioned to assess dye penetration. The results were analysed using ANOVA and Bonferroni statistical tests. The level of significance was set at p < 0.05.

RESULTS

The microleakage recorded in zirconia crowns was significantly worse than that in preveneered PMCs and PMCs (p < 0.001). Regardless of the crown type, resin cement resulted in the least microleakage with statistically significant differences from glass ionomer cement (p < 0.05).

CONCLUSION

As far as microleakage is concerned, preveneered PMCs seem to be an aesthetic and suitable alternative to PMCs. In addition, resin cement stands to be the most optimum luting cement.

Walia, Tarun & Brigi, Carel & Ziadkhani, Mona & Khayat, Afaf & Tabibzadeh, Zohreh. (2021). Retention Force of Glass Ionomer Based Luting Cements with Posterior Primary Zirconium Crowns – A Comparative in Vitro Study. Journal of Clinical Pediatric Dentistry. 45. 259-264. 10.17796/1053-4625-45.4.7.

PURPOSE

To determine the retentive force of three glass-ionomer luting cements used with prefabricated primary zirconium crowns (PPZCs) and to assess whether the retentive force was dependent on cementation material or different PPZCs brands.

METHODS

Four mandibular right second molar PPZCs were selected, one each from four manufacturers-NuSmile®ZR, Sprig Crowns, Cheng Crowns and Kinder Krowns. Silicone impressions of the outer surface of crowns were taken; stone dies prepared and reduced to fit the corresponding brand. 24 alginate impressions of each die obtained and filled with core buildup flowable composite. 96 composite tooth-replicas thus achieved were divided into four groups and further categorized into three subgroups of eight samples based on luting cements used - BioCem, FujiCEM®2 and KetacCem. Samples were thermocycled, placed in artificial saliva for one week followed by assessment of retentive force for crown dislodgment and failure mode.

RESULTS

Data was statistically evaluated using two-way ANOVA, HSD (P <0.05). KetacCem had the lowest retentive force while BioCem showed comparatively higher value to FujiCEM®2. Adhesive failure modes were predominant with cement mainly adhering to crown's internal surface.

CONCLUSION

Resin-based GI cements offered superior retention than conventional GI cements for PPZCs and retentive force was dependent on cement type.