Pulpitis is generally caused by the progression of dental caries. Bacteria infect the hard tissues of the tooth, which is referred to as dental caries in the early stages. If the decayed parts are not removed in time for dental filling, meaning the teeth are not filled promptly, the bacteria will further infect the pulp tissue, leading to pulpitis. Pulpitis is actually the outcome of further bacterial development. However, if pulpitis is not treated in time, the inflammation can advance to the root apex, causing apical periodontitis. Therefore, pulpitis requires prompt endodontic treatment of the tooth. After controlling the inflammation, the root canal is filled. Following the filling of the root canal, the top of the tooth crown is sealed, which involves the filling of the tooth.