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restorations for pulpotomized teeth.104 With regards to gingival health adjacent to preformed metal crowns, a one year RCT showed no difference in gingival inflammation between preformed metal crowns and composite restorations after pulpotomy.99 Yet, a two year randomized clinical study showed more gingival bleeding for preformed metal crowns vs. composite/glass ionomer restorations.100 Inadequately contoured crown and residues of set cement remaining in contact with the gingival sulcus are BEST PRACTICES: RESTORATIVE DENTISTRY THE REFERENCE MANUAL OF PEDIATRIC DENTISTRY 345 suggested as reasons for gingivitis associated with preformed metal crowns, and a preventive regime including oral hygiene instruction is recommended to be incorporated into the treatment plan.98 There is one RCT on preformed metal crowns versus cast crowns placed on permanent teeth,105 and this report found no difference between the two restoration types for quality and longevity after 24 months. The remaining evidence is case reports and expert opinion concerning indications for use of preformed metal crowns on permanent molars. The indications include teeth with severe genetic/developmental defects, grossly carious teeth, and traumatized teeth, along with tooth developmental stage or financial considerations that require semi-permanent restoration instead of a permanent cast restoration.97,102,105 The main reasons for preformed metal crown failure reportedly are crown loss16,103,106 and perforation106. One method of providing preformed metal crowns is known as HT.107 This method calls for cementation of a SSC over a caries-affected primary molar without local anesthetic, caries removal, or tooth preparation. It is a less invasive caries management procedure for treating carious primary teeth and involves the concept of caries control by managing the activity of the biofilm.108 This technique was developed for use when delivery of ideal treatment was not feasible. Using the HT may reduce discomfort from local anesthetic and caries removal at the time of treatment compared to fillings,107 but it may add the discomfort of placement of separator bands prior to the SSC, as well as the pain from biting the crown into place.109 The HT has gained some popularity in the United Kingdom (UK),107 primarily from use by general dentists (who provide the majority of care for young children).110 All prospective investigations on the effectiveness of HT have been by general dentists in UK, and comparison groups include restorative treatment as traditionally provided in those settings, where traditional use of SSCs to restore caries in primary teeth has not been a popular or a frequently used technique.111-114 This is in spite of the existence of guidelines and policy statements from the British Society of Paediatric Dentistry that SSCs are the restoration of choice for primary molars with multi-surface lesions or extensive caries or when pulp treatment has been performed.115,116 Results of a 2003 repeat questionnaire of general dentists in the UK showed that the use of amalgam had declined with an increase in the use of GIC and very little change in the use of SSCs.111 Placement of GIC restorations or observation without treatment was the management approach of choice, and the use of local anesthesia to provide dental care to children was infrequent.112 Given the differences in treatment approaches in health care settings and system between countries, the HT has not been widely adopted in the U.S., and it usually is limited to individual situations where proven methods of caries management cannot be used.117 Studies that compare this technique to traditionally placed preformed metal crowns using radiographic assessment and caries removal are needed.117 Recent retrospective studies118,119 for cost-effectiveness combined with a cross-sectional evaluation of patient acceptance showed that 95.8 percent of primary teeth restored using the HT remained asymptomatic after a follow-up period of up to 77 months, compared to 95.3 percent in the conventional methods (caries removal with placement of SSC or other restoration); they did not, however, report a breakdown by follow-up