Root Canal Obturation: An Updated Review of the Literature

Background: Root canal obturation can be performed using cold lateral condensation, warm compaction, carrier-based systems, thermoplasticized techniques, and simplified single-cone/sealer-based protocols. Laboratory studies demonstrate technique-dependent differences in filling density, adaptation, and material distribution, but the extent to which these differences translate into superior clinical outcomes remains uncertain. Methods: This systematic review focused on direct comparative human clinical studies of distinct root canal obturation strategies. MEDLINE was searched through PubMed from database inception to 1 September 2026 and Scopus was searched from database inception to 3 September 2026, without year or language restrictions. Database-specific reproducible search strategies used obturation and technique terms without outcome filters. Records were deduplicated by PMID, DOI, and normalized title matching. Reference lists of relevant systematic reviews and eligible studies were used as supplementary citation sources. Randomized studies were appraised with RoB 2 and non-randomized comparative studies with ROBINS-I. Results: The searches identified 1404 PubMed/MEDLINE records and 4636 Scopus records (6040 records before deduplication). After removal of 1280 duplicate records, 4760 unique records were screened. Sixty-seven reports underwent detailed eligibility assessment; 45 reports representing 42 comparative clinical studies were included. The Scopus search contributed 16 additional eligible studies not retrieved by the PubMed strategy. Across long-term clinical and radiographic outcomes, no obturation strategy demonstrated consistent superiority. Contemporary sealer-based/single-cone protocols generally produced outcomes comparable with warm compaction, while technique-related differences were more apparent for postoperative pain, obturation time, radiographic filling quality, and extrusion in individual studies. Conclusions: Current comparative clinical evidence does not support a universally superior root canal obturation strategy. Technique selection should therefore consider canal anatomy, operator experience, procedural efficiency, retreatment requirements, and material-specific handling characteristics. More adequately powered, prospectively registered, multicenter randomized trials with standardized long-term outcome assessment are needed.