Pulp Polyp

Updated: Apr 30, 2014
  • Author: Catherine M Flaitz, DDS, MS; Chief Editor: Arlen D Meyers, MD, MBA  more...
  • Print


The pulp polyp, also known as chronic hyperplastic pulpitis or proliferative pulpitis, is an uncommon and specific type of inflammatory hyperplasia that is associated with a nonvital tooth.

Pulpal diseases are broadly divided into reversible and irreversible pulpitis and are based on the ability of the inflamed dental pulp to return to a healthy state once the noxious stimulus has been removed. In the case of the pulp polyp, the disease process is irreversible. In contrast to most cases of irreversible pulpitis, the pulp polyp is usually an incidental finding that occasionally mimics reactive and neoplastic diseases of the gingiva and adjacent periodontium.

Pulp polyps involving the primary, first, and seco Pulp polyps involving the primary, first, and second mandibular molars in a young child with extensive dental caries.


The pulp polyp is the result of both mechanical irritation and bacterial invasion into the pulp of a tooth that exhibits significant crown destruction due to trauma or caries. The mechanical causes that may stimulate this response include a tooth fracture with pulpal exposure or loss of a dental restoration. Usually, the entire dentinal roof is exposed with the crown of a carious tooth. The large exposure of pulpal tissue to the oral environment and bacterial invasion results in a chronic inflammatory response that stimulates an exuberant granulation tissue reaction.

The hyperplastic tissue reaction occurs because the young dental pulp has a rich blood supply and favorable immune response that is more resistant to bacterial infection. Furthermore, because the tooth is open to the oral cavity, transudates and exudates from the inflamed pulpal tissue drain freely and do not accumulate within the restricted and rigid confines of the tooth. Tissue necrosis with destruction of the microcirculation that usually accompanies irreversible pulpitis does not occur in part because of this lack of significant intrapulpal pressure. In young teeth in which the apex of the root is open, the risk of pulpal necrosis secondary to venous congestion is decreased. The presence of a rich vascular network in the young pulpal tissue is an important protective mechanism against the inflammatory response that significantly decreases with age.

The possible role of a type 1 hypersensitivity reaction has been hypothesized because of an increased presence and concentration of immunoglobulin E (IgE), histamine, and interleukin-4 (IL-4) within the pulp polyps when compared with healthy pulpal tissues. [1]




United States

Pulp polyps are reportedly uncommon in the United States, and no epidemiologic studies specifically document the frequency of this entity. Although this lesion is reported to be uncommon with only isolated references in the literature, the true prevalence of this reactive pulpal disease is likely to be underestimated because it is a well-recognized sequela of extensive dental caries in children.


Pulp polyps are uncommon in countries with routine access to dental care, but they are encountered more frequently in developing countries. In a study of Vietnamese refugees who sought dental care, the prevalence of pulp polyps was 6%. This high number of cases is an indication of the severity of dental disease in this impoverished population. In a Brazilian clinical study of traumatized primary teeth, the occurrence of pulp polyps was 2.3% in young children. [2]


Pulp polyps tend to be asymptomatic and are not associated with any significant morbidity or mortality except for gross caries destruction with premature tooth loss in many cases.


No racial predilection is recognized for this sequela of dental caries; however, it is more common in individuals of lower socioeconomic background who have limited access to dental care than in other people.


No sexual predilection has been documented for this oral lesion.


This pulpal disease occurs almost exclusively in children and young adults, and it can occur in both the primary dentition and the permanent dentition. When trauma is the causative factor in primary anterior teeth, most examples are observed in children aged 2 years or younger.