Etiology
The pulp calcifications can arise due to:

pulp degeneration
increasing age
circulatory disturbances within the pulp
long standing local irritants such as dental caries, pulp-capping procedures, healed tooth fractures, tooth injury restorations and periodontal diseases
orthodontic tooth movements
transplantation of teeth
traumaIt is shown that pulp stone occurring in adolescents is significantly associated with carious and/or restored teeth, which suggests a causative relationship of chronic pulp irritation to pulp stone formation. A defence reaction in the pulpodentinal complex may be triggered by caries and microleakage around restorations which lead to pulp calcifications. The formation of pulp stone may have a similar mechanism as the tertiary dentine formation near the irritated odontoblasts. Apart from that, with aging, the pulp decreases in size due to the deposition of secondary or tertiary dentine. This subsequently results in favourable conditions for the formation of pulpal calcifications. The other reported etiologic factors also include:

idiopathic factors
consumption of fluoride supplements
hypervitaminosis D
a possible genetic predisposition such as dentinogenesis imperfecta and dentinal dysplasia

Types/classification
Pulp stones can be classified based on different location and structure. Based on location, they can classified into free, embedded and adherent pulp stones. Free pulp stones are found within the pulp tissue and is the most common encounter. The size vary from 50μm in diameter to several millimetres and may occlude the entire pulp chamber. Embedded pulp stone is fully embedded in dentine and most commonly found in the apical portion of the root. Adherent pulp stones are attached to the wall of pulp space but not fully enclosed by dentine.
See also
Restasis (ciclosporin eye drops for keratoconjunctivitis sicca)


== References ==