Pre-formed crowns and pediatric dentistry: a systematic review of different techniques of restorations

Background: The preservation of primary dentition is crucial not only for aesthetic reasons but also to restore a proper masticatory function, stabilize the occlusion, and prevent potential complications and malocclusions in the permanent dentition. The restoration of primary teeth may require the use of preformed crowns rather than a simple composite filling (e.g., the ART—Atraumatic Restorative Treatment—technique). At the clinician’s discretion, the placement of preformed crowns can be carried out using traditional techniques or the innovative Hall technique. This review aims to investigate the pros and cons of different techniques and teeth preparations. Methods: Employing PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses) guidelines, a search of PubMed, Scopus and Web of Science from January 2013 to October 2023 was conducted. The included studies, encompassing randomized clinical trials and retrospective studies, explored the relationship between HT (Hall Technique) and direct and indirect restorations in pediatric dentistry. Results: After an initial database search yielding 1216 articles, 12 records were selected for qualitative analysis. Quality assessment was performed using the ROBINS (Risk Of Bias In Non-randomized Studies) tool, revealing variable risk of bias across studies.Searching online databases was performed to find papers that matched the topic. Overall results indicate that the Hall technique is comparable or superior to conventional techniques in terms of clinical success, with some evidence suggesting long-term economic benefits. Conclusions: The Hall technique represents a promising, biologically oriented option for the management of carious lesions in deciduous molars. Further prospective, randomized research is needed to consolidate this evidence and fully understand the clinical and economic implications of the Hall technique compared with conventional techniques. The PROSPERO Registration: This systematic review was conducted according to PRISMA and the protocol was registered at PROSPERO under the identification: CRD 42024519578.

Pedodontics; Dental restoration; Dental crowns; Hall technique; Prosthodontic

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