Evaluation of the Effect of Glass Ionomer Cement as an Interim Restoration in Diagnosis of Pulpal Status in Permanent Teeth: A Prospective Randomized Clinical Trial

Introduction Preservation of pulp vitality while managing the deep carious lesions is often a great challenge and requires procedures like pulp capping and pulpotomy collectively termed as vital pulp therapy (VPT). Such treatment involves elimination of bacteria from pulp dentine complex and establishing an environment that will prevent any future bacterial contamination and improves survival prognosis. Management of deep carious lesions in recent years has changed from complete caries removal to partial caries removal. Partial caries removal has gained importance due to reduction in pulpal exposures, less postoperative complications, more preservation and maintenance of pulp tissue .

The important concern during VPT is accurate assessment of pulpal status. Methods to determine pulpal vitality include patient history, signs and symptoms, radiographs and pulp sensibility tests. One of the hallmarks of pulpal diagnosis is that it is difficult and has a high rate of inaccuracy. Pain on cold and hot stimuli cannot be considered as a reliable reference for making a treatment decision. Also insufficient evidence was found to determine the diagnostic accuracy of symptoms, signs, and diagnostic tests to assess the pulp status.

Studies using visual and histological inspection of exposed pulp to examine status of pulp reported marked variation in sensitivity of cold and electric pulp test from 0 .21 to 0.94, with relatively less variation in specificity from 0.73 to 0 .96.Sensitivity decreased to 67% when the spectrum of the disease was altered i.e. when asymptomatic teeth with deep carious lesions were included . Diagnosis of pulp status is often easy when there is a clear distinction between healthy and necrosed pulp however it is more difficult in asymptomatic teeth with deep carious lesions.

Recently, Coll et al. proposed that glass ionomer cement (GIC) as interim therapeutic restoration (ITR) improved pulpal diagnosis and VPT outcomes while interpreting diagnostic assessment based on clinical pulp therapy success. Vij et al. reported that GIC temporization for 1-3 months increased success of the subsequent VPT from 79% to 92% .However; both of the studies were retrospective and were in deciduous teeth.

No prospective clinical study has so far been conducted in permanent teeth that demonstrate the effectiveness of GIC and other adhesive restoration materials in determining the pulpal status. Aim of this double blinded randomized controlled trial was to assess the effectiveness of GIC interim restoration in determining the pulpal status of asymptomatic teeth with deep carious lesions. Null hypothesis was that GIC as ITR does not improve the clinician's diagnostic ability to determine the correct pulp clinical diagnosis and does not improve the treatment outcomes in vital pulp therapy.