Debra Ferraiolo DMD, FAGD; Silvia Spivakovsky DDS
In most aspects, calcium hydroxide and resin-modified glass ionomer cement seem to elicit similar pulp response; however, this review could not provide a conclusive statement as all included studies exhibited high risk of bias.
The small number of low quality studies provides equivocal evidence; therefore, the clinician may consider both materials when restoring deep lesions.
Does resin-modified glass ionomer cement (RM-GIC) placed in deep cavities generate a pulp response different from that of calcium hydroxide ?
The authors performed a comprehensive search of five databases for articles published through May 2009. Two of the authors independently reviewed the studies, resolving disagreements by applying pre-determined criteria. The authors included clinical trials with two arms (randomized or not) published in English if data on pulpal response were available.
Of the 31 articles obtained by the search, six trials (one randomized and five non-randomized) met the inclusion criteria. Overall, the studies evaluated 923 permanent and 27 primary teeth. Two independent reviewers assessed the quality of the accepted trials. The authors compiled the results on 18 datasets of outcomes. Of those datasets, 14 showed relative risk (RR) with 95% confidence interval (CI) not to be statistically significant (p>0.05). The authors found statistically significant differences favoring calcium hydroxide in the inflammatory cell response (RR=0.61; 95% CI, 0.50-0.76; p
The data from non-randomized trials provided only a small, statistically-significant difference favoring calcium hydroxide, when the authors assessed pulpal inflammatory response, hard/soft tissue repair, or changes in odontoblasts numbers using the two tested materials.
Source of Funding:
Importance and Context:
In the past calcium hydroxide was systematically used as a base material during most restorative procedures . Despite the evidence that it is not the most effective treatment clinicians continue to use calcium hydroxide and remains the material of choice specially in cases with minimal remaining dentine thickness (RDT).
Strengths and Weaknesses of the Systematic Review:
The reviewers started with a clear clinical question and performed a comprehensive search of the English literature. Two independent reviewers checked for inclusion criteria and performed quality assessment. Due to methodological differences, the authors used only three groups of datasets for meta-analysis. The authors analyzed the results using a large number of subsets of dichotomous data. As a result, most individual outcome results were based on very small populations (n
Strengths and Weaknesses of the Evidence:
The length of exposure of included studies varied from 7 to 381 days. All the non-randomized trials dealt with non-carious lesions in permanent teeth, while the randomized control trial (RCT) dealt with a small number of carious primary teeth. This RCT showed no statistically significant differences. The results from the non-randomized trials may have been influenced by selection bias and the lack of blinding from the evaluators.
Implications for Dental Practice:
The review presents inconclusive evidence of differences between RM-GIC and calcium hydroxide. The practitioner may consider both materials when restoring deep lesions. Using a biocompatible material like RM-GIC may offer additional benefits due to its chemical and mechanical properties. Because of its chemical bond to mineralized tissue, the application of RM-GIC is simple and can be done in a single step. The mechanical properties offer additional benefits since it can be used as temporary as well as permanent restorative material.