Comparison of effect of desensitizing agents on the retention of crowns cemented with luting agents: an in vitro study

The Effect of Dentine Desensitizing Agents on the Retention of Cemented Fixed Dental Prostheses: A Systematic Review

Background and Objectives: The use of desensitizing agents (DA) after tooth preparation to prevent hypersensitivity is well documented in the literature. A fixed dental prosthesis (FDP) should have good retention to be successful. Inadequate retention may result in microleakage, secondary caries, and, eventually, dislodgement of the FDP. The effect of DAs on the retention of FDPs has been widely studied in the literature, but the results are conflicting. Thus, this study aimed to conduct a systematic review to assess the effect of dentine desensitizing agents, used to prevent post-cementation hypersensitivity, on the retention of cemented FDPs. The null hypothesis framed was that there is no effect of dentine desensitizing agents on the retention of cemented FDPs. The focused PICO question was as follows: “Does the application of dentine desensitizing agents (I) affect the retention (O) of cemented fixed dental prosthesis (P) when compared to non-dentine desensitizing groups (C)”? Materials and Methods: Four electronic databases were systematically searched and, on the basis of the predefined inclusion and exclusion criteria, 23 articles were included in this systematic review. A modified CONSORT scale for in vitro studies was used to assess the quality of the selected studies, as all included studies were in vitro studies. Results: Most of the studies compared the effect of more than one type of DA on retention. The results of the selected studies varied due to differences in the composition of tested dentine DAs and types of luting cements. Conclusions: Within the limitations of this study, it can be concluded that the retention values of FDPs cemented using zinc phosphate cement were reduced with most of the DAs, whereas retention values increased when GIC, resin-modified GIC, and resin cements were used with the majority of DAs. These findings are important, as they can guide dentists in selecting the DA before cementing the crowns with the luting agent of their choice, without compromising the retention of the crowns.

The Effect of Commercially Available Desensitizers on Bond Strength Following Cementation of Zirconia Crowns Using Self-Adhesive Resin Cement-An In Vitro Study

The improvement of the tensile strength of zirconia crowns after the application of commercially available desensitizers can provide added advantages for the durability and strength of zirconia prostheses. We assessed the retention of zirconia crowns when Gluma, Shield Force Plus, and Telio CS desensitizers were used with resin luting cement. Four groups with ten specimens each (n = 10) were considered as Group 1 (Control group, with no desensitizer application before crown cementation with resin cement) and Groups 2, 3, and 4 (with a single coat of Gluma dentin desensitizer, Telio CS desensitizer, or Shield Force Plus desensitizer applied before crown cementation, respectively). Thermocycling was then carried out, and each group was tested to determine the associated retentive forces and type of failure. The data were statistically analyzed, which showed that the mean tensile-strength values were significantly higher in Group 2 (p-value = 0.001), Group 3 (p-value = 0.027), and Group 4 (p-value = 0.014), when compared with the Control group. Clinicians should consider the application of any of these three desensitizers, as they can successfully abate dentin hypersensitivity after tooth preparation, as well as increase the durability and strength of the zirconia prosthesis.

The Effect of Dentin Treated with Calcium Phosphate Desensitizer on Shear Bond Strength with Different Resin Cement: An In Vitro Study

Aim:

The aim of this study was to evaluate the effect of calcium phosphate based desensitizing agent on shear bond strength of self-etch/adhesive resin cements to dentin.

Materials and Methods:

Eighty dentin specimens were prepared from freshly extracted human third molar teeth and were classified, randomly ( n = 20). Half of groups were treated with calcium phosphate based Teethmate Desensitizer and then Panavia V5, RelyX Ultimate (containing self-etch primer), Panavia SA, and RelyX U200 self-adhesive resin cements were luted to all dentin surfaces. All specimens were stored in an incubator at 37°C for 24 h. Shear bond strength was tested by a universal test machine at a 0.5 mm/min crosshead speed. The data were analyzed with a statistical program. Two-way ANOVA was used for statistical differences ( P <.05). Dentin surfaces were examined with scanning electron microscopy (SEM) at x5000 and x10000 magnifications.

Results:

The higher shear bond values were observed in the groups with Teethmate Desensitizer applied and cemented with self-etch (16.05 ± 6.24 and 14.73 ± 4.75), whereas the lowest bonding values were observed in the groups with self-adhesive resin cement without Teethmate Desensitizer (3.73 ± 0.77 and 5.85 ± 4.19; P <.001). As the main effect of the treatment, the bond strength was 9.39 ± 6.04 in the control group, whereas it was 13.49 ± 5.44 in the Teethmate applied groups ( P <.05)

Conclusions:

Calcium phosphate desensitizer did not adversely effected shear bond strength of self-etch/adhesive resin cements to dentin. It even significantly increased the shear bond strength of self-adhesive resin cements.

Cement selection criteria for full coverage restorations: A comprehensive review of literature

BACKGROUND

Proper cement selection in fixed prosthesis plays a determinative role in providing long-term serviceability, retention, caries prevention, and patient satisfaction. This study, reviews different luting agent characteristics and their application based on different clinical situations and different types of full coverage restorations.

MATERIAL AND METHODS

An electronic search was conducted through PubMed, Medline, and Google scholar using following keywords or combinations: restoration, full coverage, PFM, porcelain fused to metal, all ceramic, zirconia, ceramic, casting, fixed partial denture, cement*, dental cement, cement selection, and retention. The most related articles were selected for review.

RESULTS

Choosing a proper luting agent is highly dependent on scientific knowledge regarding the characteristics of restorative materials and luting agents. Conventional cements could be indicated in various situations; however, some restorative materials or clinical situations call for resin-cements to provide predictable retention, support, and durability.

CONCLUSIONS

Conscious selection of retentive cement for each type of restoration/material is necessary to provide predictable successful treatment and reduce the potential complications. Key words:Adhesive cement, dental bridgework, dental cements, dental crowns, dental porcelain, prostheses and implants.

Retention of CAD/CAM resin composite crowns following different bonding protocols

PURPOSE

To evaluate the effect of different surface treatments and primers with a CAD/CAM resin composite block on its crown retention.

METHODS

120 human molars were prepared with a 24° total convergence angle, 1.5 mm height, and axial walls in dentin. Surface area was measured by digital microscopy. Crowns were machined from CAD/CAM resin composite blocks. Teeth were randomly allocated to 12 groups (n= 10) based on possible combinations of three surface treatments: [Control, Alumina air abrasion (50-µm Al₂O₃ at 0.28 MPa) ]; 5% hydrofluoric acid etch (20-second scrub); silane application (with or without Kerr Silane primer); and adhesive application (with or without Optibond XTR Adhesive). Optibond XTR Adhesive was applied to the tooth preparations and crowns were bonded with MaxCem Elite cement. Crowns were fatigued for 100,000 cycles at 100 N in water and debonded in tension (1 mm/minute). Crown retention strength (maximum load/surface area) values were analyzed using a three-way ANOVA with Tukey's post-hoc tests (α= 0.05).

RESULTS

Surface treatment, silane and adhesive applications independently affect retention force (P< 0.05). All interactions were not significant (P> 0.05). Alumina airborne abrasion surface treatment, silane and adhesive applications all improve retention strength. Therefore, CAD/CAM resin composite crowns can withstand debonding while undergoing mechanical fatigue. Although all forms of surface treatment and primer application improve bond strength, the highest mean retention strength values were recorded when the crowns were alumina particle abraded and coated with adhesive (with or without silane).

CLINICAL SIGNIFICANCE

In order to improve the bonding of resin composite crowns, application of alumina airborne particle abrasion and a coat of adhesive (proceeded by an optional coat of silane) is recommended. If hydrofluoric acid is utilized, the crowns should be treated with a coat of silane followed by adhesive application.

Effect of GLUMA desensitizer on the retention of full metal crowns cemented with Rely X U200 self-adhesive cement

PURPOSE

Considering the importance of retention in the success and long-term clinical service of fixed partial dentures (FPDs) as well as the existing controversy regarding the effect of GLUMA desensitizer on the retention of full metal crowns cemented with RelyX U200 self-adhesive cement, this study aimed to assess the effect of GLUMA desensitizer on the retention of full metal crowns cemented using RelyX U200.

MATERIALS AND METHODS

In this experimental study, 20 sound human premolars were prepared; a 0.5 mm chamfer finish line was prepared above the cementoenamel junction. The teeth were randomly assigned to two groups: a desensitizer group (n = 10, treated with GLUMA desensitizer) and a control (n = 10, no surface treatment). Full metal crowns were fabricated of base metal alloy and had a ring. All crowns were cemented with RelyX U200 and subjected to retention test by using a universal testing machine. The data were analyzed using SPSS version 20 and independent t-test.

RESULTS

The mean tensile bond strength was significantly higher in the GLUMA desensitizer group (230.63 ± 63.8 N) compared to the control group (164.45 ± 39.3 N) (P≤.012).

CONCLUSION

GLUMA desensitizer increases the tensile bond strength of RelyX U200 self-adhesive cement to dentin.

The Retentive Strength of Cemented Zirconium Oxide Crowns after Dentin Pretreatment with Desensitizing Paste Containing 8% Arginine and Calcium Carbonate

The effect of dentin pretreatment with Desensitizing Paste containing 8% arginine and calcium carbonate on the retention of zirconium oxide (Y-TZP) crowns was tested. Forty molar teeth were mounted and prepared using a standardized protocol. Y-TZP crowns were produced using computer-aided design and computer-aided manufacturing (CAD-CAM) technology. The 40 prepared teeth were either pretreated with Desensitizing Paste or not pretreated. After two weeks, each group was subdivided into two groups, cemented with either Resin Modified Glass Ionomer Cement (RMGIC) or Self Adhesive Resin Cement (SARC)). Prior to cementation, the surface areas of the prepared teeth were measured. After aging, the cemented crown-tooth assemblies were tested for retentive strength using a universal testing machine. The debonded surfaces of the teeth and crowns were examined microscopically at 10× magnification. Pretreating the dentin surfaces with Desensitizing Paste prior to cementation did not affect the retention of the Y-TZP crowns. The retentive values for RMGIC (3.04 ± 0.77 MPa) were significantly higher than those for SARC (2.28 ± 0.58 MPa). The predominant failure modes for the RMGIC and SARC were adhesive cement-dentin and adhesive cement-crown, respectively. An 8.0% arginine and calcium carbonate in-office desensitizing paste can be safely used to reduce post-cementation sensitivity without reducing the retentive strength of Y-TZP crowns.

An in vitro evaluation of the effects of desensitizing agents on microleakage of Class V cavities

Background

The aim of this study was to evaluate the effect of a desensitizing agent on microleakage of Class V cavities.

Material and Methods

72 premolar teeth were used. There were 6 groups. Class V restorations were prepared with two different restorative materials (Equia fil, GC, America and Grandio, VOCO, Germany) and two adhesive systems (Clearfil SE Bond, Kuraray, Japan and S3 Bond Plus, Kuraray, Japan) with and without desensitizing agent (Gluma Desensitizer, Heraeus Kulzer, Germany). Restorations were polished with aluminum oxide abrasive discs. Then a range of 5 - 55C thermocycling was performed 10.000 times. The microleakage of restorations was examined with dye penetration method (Basic fuchsine). Bonferroni corrections and Kruskal-Wallis test were used to determine the significance of differences in occlusal and gingival dye penetration scores between groups.

Results

There was no stastistical significance between the occlusal and gingival microleakage scores within the groups were shown.

Conclusions

It can be concluded that use of desensitizing agent under both high viscosity glass ionomer restorative materials and resin composites doesn’t affect the microleakage.

Key words:High viscosity glass ionomer cement, composite resin, desensitizing agent, microleakage.