PULP CALCIFICATIONS – PULP STONES (DENTICLES) AND LINEAR DIFFUSE CALCIFICATIONS
Author: Sanketh DS, MDS
INTRODUCTION & ETIOLOGY
Calcifications of the pulp are a frequent finding, which in fact, were found histologically to be present in approximately 66% of all teeth examined in persons between 10-20 years of age and in 90% of all teeth examined in persons in the 50-70 year age range. Investigators have however, reported a prevalence of only 20% in teeth, when viewed radiographically. This is probably because calcifications need to be bigger than 200µ in size to be visible in radiographs. There seems to be no difference in frequency or predilection for pulpal calcifications with regards to gender and the type of tooth. A single tooth may harbour several discrete masses of calcifications ranging from at least 1-12, which may be minute or large enough to occlude the pulp chamber.
Etiology for pulpal calcification is unknown but they have been seen in association with various factors, though these factors need not necessarily cause calcifications. Some of them are tooth injury, aging, regressive tooth alterations like attrition, abrasion and erosion and also clinical conditions like dentin dysplasia and Ehlers-Danlos syndrome.
TYPES OF PULP CALCIFICATIONS
Pulp calcifications are of two types, namely pulp stones and diffuse linear calcifications. Pulp stones are localised masses of calcifications which could be present in the coronal or root portion of the pulp, though most commonly found in the coronal pulp. Diffuse linear calcifications are linear strands of calcified material present most commonly in the root portion of the pulp.
Pulp stones also called “denticles” are classified as “true” and “false” denticles based on their microscopic structure.
True denticles are localized masses of calcifications that resemble the dentin in structure since they have dentinal tubules and are lined by odontoblasts. They more so resemble the secondary dentin since the tubules are irregular and few in number. True denticles are more often present in the coronal pulp than in the radicular pulp.
It is hypothesized that true denticles are caused due to remnants of Hertwig’s epithelial root sheath trapped in the pulp. These cells may induce the differentiation of the mesenchymal stem cells in the pulp to odontoblasts, which in turn form the calcified mass of dentin.
Unlike true denticles, false pulp stones do not resemble dentin and are concentric layers of calcified tissue. Deposition of calcium starts around a central nidus and radiates outward concentrically. False denticles are larger than true denticles and could occlude the entire pulp chamber.
Both true and false denticles are also classified based on their location as “free”, “attached” and “embedded” denticles. Free denticles are those that are entirely surrounded by pulpal tissue. While attached denticles are those that are attached or in close continuity with the dentin embedded denticles are ones that are present entirely within the dentin.
Diffuse linear calcifications
Are linear strands of calcified tissue that are irregular and run parallel to blood vessels. They are found more commonly in the radicular portion of the pulp.
There have been reports linking pulp stones to pulpal pain which could range from being mild to excruciating. Pain is thought to be caused by pulp stones impinging on nerves in the pulp. However, there is no sufficient evidence to back this claim and investigators now believe that pulp stones may not cause pain. Rarely when pulp stones become large enough to occlude the pulp chamber, it may pose difficulties for root canal procedures. Such cases could be solved by the use of ultrasonic instruments coupled with the use of sodium hypochlorite. Otherwise, pulp stones do not pose any problems and treatment is not required.
Nanci A. Tencate’s Oral Histology. Development, Structure and Function. 8th ed. Elsevier;2013.
Kumar GS. Orban’s Oral Histology and Embryology.13th ed. Elsevier;2011.
Neville BW, Damm DD, Allen CM, Chi A. Oral and Maxillofacial Pathology. South Asian ed. Elsevier; 2016.
Rajendran R, Sivapathasundaram B. Shafer’s Textbook of Oral Pathology. 6th ed. Elsevier; 2009.
OTHER (HACKDENTISTRY) PRACTICE/STUDY RESOURCES