4-Year Pulp Survival in a Randomized Trial on Direct Pulp Capping.

INTRODUCTION: This study aimed to assess pulp survival in a randomized trial on pulp lavage in adult nonpainful posterior teeth with carious pulp exposure. The treatment included complete caries excavation, direct pulp capping with mineral trioxide aggregate, and immediate restoration with composite resin. METHODS: Fluid was collected from the pulp wound to assess matrix metalloproteinase-9 (MMP-9) and total protein values. Before pulp capping, cavities were randomly (block randomization, n = 48) washed with a physiological saline or a sodium hypochlorite solution (2.5% NaOCl). Treatment outcome was assessed clinically (cold test) and radiographically after at least 1 year and again after at least 3 years. Painful failures were differentiated from nonpainful failures. Pulp survival was estimated using the Kaplan-Meier method including 95% confidence intervals (CIs) up to 1500 days. RESULTS: From the 96 patients originally enrolled, 73 individuals could be followed continuously. The clinical observations indicated a beneficial and sustained effect of pulp lavage with 2.5% NaOCl over a control treatment with physiological saline solution on estimated pulp survival 1500 days postintervention, with 7% (95% CI, 1%-40%) in the saline group versus 55% (95% CI, 30%-100%) in the NaOCl group. High MMP-9/total protein values in pulpal fluid collected from the exposed site indicated early and painful treatment failures yet were not associated with failures that occurred more than 250 days after intervention. CONCLUSIONS: The low 4-year success rates reported here challenge the concept of direct pulp capping in the cases that were included. NaOCl lavage did not only increase the survival of affected pulps substantially but also particularly diminished painful failures (33% in the NaOCl group vs 62% in the saline group). The lack of the predictive value of MMP-9 assessments beyond early treatment failures points to inflammatory states of the pulp tissue under deep caries, which are not related to neutrophil infiltration.

Effect of Maleic Acid Root Conditioning on Release of Transforming Growth Factor Beta 1 from Infected Root Canal Dentin.

INTRODUCTION: Chemically released growth factors play a vital role in regenerative endodontics. Transforming growth factor beta 1 (TGF-ß1) is 1 of the most extensively studied bioactive molecules that promotes cell proliferation, differentiation, and chemotaxis. The goal of the current research was to analyze the effect of 7% maleic acid (MA) root conditioning of an infected root canal on the release of TGF-ß1. METHODS: Single-rooted human teeth were decoronated, and the canals were enlarged with a Peeso reamer. The samples were divided into biofilm and nonbiofilm groups. Subsequently, all the samples of both groups were flushed with 10 mL of each irrigant, namely, 1.5% sodium hypochlorite (NaOCl), 7% MA, 17% EDTA, and a combination of 1.5% NaOCl with 17% EDTA or 7% MA, for 10 minutes each. TGF-ß1 was estimated quantitatively using an enzyme-linked immunosorbent assay kit. RESULTS: TGF-ß1 release was lowest among the biofilm samples compared with nonbiofilm among all the groups. MA 7% with 1.5% NaOCl rendered higher amounts of growth factor release in contrast to the combination of 17% EDTA and 1.5% NaOCl in both the biofilm and nonbiofilm groups (P < .048). The nonbiofilm samples treated with 7% MA alone illustrated higher growth factor release compared with 17% EDTA only (P < .006), but there was no significant difference in growth factor release among the biofilm samples treated with 7% MA and 17% EDTA. CONCLUSIONS: Bacterial biofilms modified the release of TGF-ß1. MA 7% was observed to be significantly more efficacious than 17% EDTA in TGF-ß1 growth factor release from radicular dentin.