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cements has value as single surface temporary restoration for both primary and permanent teeth. Additionally, ITR may be used for caries control in children with multiple open carious lesions, prior to definitive restoration of the teeth. Compomers Polyacid-modified resin-based composites, or compomers, were introduced into dentistry in the mid-1990s. They contain 72 percent (by weight) strontium fluorosilicate glass and the average particle size is 2.5 micrometers.90 Moisture is attracted to both acid functional monomer and basic ionomer-type in the material. This moisture can trigger a reaction that releases fluoride and buffers acidic environments.91,92 Considering the ability to release fluoride, esthetic value, and simple handling properties of compomer, it can be useful in pediatric dentistry.90 Based on a recent RCT, the longevity of Class I compomer restorations in primary teeth was not statistically different compared to amalgam, but compomers were found to need replacement more frequently due to recurrent caries.46 In Class II compomer restorations in primary teeth, the risk of developing secondary caries and failure did not increase over a two-year period in primary molars.54,93 Compomers also have reported comparable clinical performance to composite with respect to color matching, cavo-surface discoloration, anatomical form, and marginal integrity and secondary caries.94,95 Most RCTs showed that compomer tends to have better physical properties compared to glass ionomer and resin modified glass ionomer cements and in primary teeth, but no significant difference was found in cariostatic effects of compomer compared to these materials.49,93,96 Recommendations: 1. Compomers can be an alternative to other restorative materials in the primary dentition in Class I and Class II restorations. 2. There is not enough data comparing compomers to other restorative materials in permanent teeth of children. Preformed metal crowns Preformed metal crowns also known as SSCs are prefabricated crown forms that are adapted to individual teeth and cemented with a biocompatible luting agent. Preformed metal crowns have been indicated for the restoration of primary and permanent teeth with extensive caries, cervical decalcification, and/or developmental defects (e.g., hypoplasia, hypocalcification), when failure of other available restorative materials is likely (e.g., interproximal caries extending beyond line angles, patients with bruxism), following pulpotomy or pulpectomy, for restoring a primary tooth that is to be used as an abutment for a space maintainer, for the intermediate restoration of fractured teeth, and for definitive restorative treatment for high caries-risk children. They are used more frequently in patients whose treatment is performed under sedation or general anesthesia.97-99 There are very few prospective RCTs comparing outcomes for preformed metal crowns to intra-coronal restorations.100,101 A Cochrane review and two systematic reviews conclude that the majority of clinical evidence for the use of preformed metal crowns has come from nonrandomized and retrospective studies.16,97-99 However, this evidence suggests that preformed metal crowns showed greater longevity than amalgam restorations,16 despite possible study bias of placing SSCs on teeth more damaged by caries.98,99,102 Five studies which retrospectively compared Class II amalgam to preformed metal crowns showed an average five year failure rate of 26 percent for amalgam and seven percent for preformed metal crowns.98 A two-year RCT regarding restoration of primary teeth that had undergone a pulpotomy procedure found a nonsignificant difference in survival rate for teeth restored with preformed metal crowns (95 percent) versus resin modified glass ionomer/composite restoration (92.5 percent).100 In another prospective study, significantly fewer restoration failures and improved calcium hydroxide pulpotomy success were found with preformed metal crowns (79.7 percent) versus amalgam restorations (60 percent) after one year.103 However, a systematic review did not show strong evidence that preformed metal crowns were superior over other