Stimulation of Dentin Regeneration by Using Acemannan in Teeth with Lipopolysaccharide-induced Pulp Inflammation

Introduction: This study investigated the effects of acemannan, a polysaccharide from Aloe vera, on human deciduous pulp cells in vitro and the response after vital pulp therapy in dog deciduous teeth. Methods: Human primary dental pulpal cells were treated with acemannan in vitro and evaluated for proliferation, alkaline phosphatase activity, type I collagen, bone morphogenetic protein (BMP-2), BMP-4, vascular endothelial growth factor, and dentin sialoprotein expression and mineralization. Osteogenesis-related gene expression was analyzed by complementary DNA microarray. Pulpal inflammation was induced in dog teeth for 14 days. The inflamed pulp was removed, retaining the healthy pulp. The teeth were randomly divided into 3 treatment groups: acemannan, mineral trioxide aggregate, and formocresol. Sixty days later, the teeth were extracted and evaluated histopathologically. Results: Acemannan significantly increased pulp cell proliferation, alkaline phosphatase, type I collagen, BMP-2, BMP-4, vascular endothelial growth factor, and dentin sialoprotein expression and mineralization approximately 1.4-, 1.6-, 1.6-, 5.5-, 2.6-, 3.8-, 1.8-, and 4.8-fold, respectively, compared with control. In vivo, partial pulpotomy treatment using acemannan generated outcomes similar to mineral trioxide aggregate treatment, resulting in mineralized bridge formation with normal pulp tissue without inflammation or pulp necrosis. In contrast, the formocresol group demonstrated pulp inflammation without mineralized bridge formation. Conclusions: Acemannan is biocompatible with the dental pulp. Furthermore, acemannan stimulated dentin regeneration in teeth with reversible pulpitis.