Cementicle

 ( Periodontal Disorders ) 

There are 3 types:

• Free cementicle – not attached to cementum
  (2010). 9788184484021, Jaypee Brothers Publishers. . ISBN 9788184484021
• Attached (sessile) cementicle – attached to the cementum surface (also termed exocementosis)
• Embedded (interstitial) cementicle – with advancing age the cementum thickens,
  Kumar GS (2014). 9788131238011, Elsevier Health Sciences APAC. . ISBN 9788131238011
  and the cementicle may become incorporated into the cementum layer

They may be visible on a radiograph (x-ray). They may appear singly or in groups, and are most commonly found at the tip of the root. Their size is variable, but generally they are small (about 0.2 mm

Cementicles are usually acellular, and may contain either fibrillar or afibrillar cementum, or a mixture of both. Cementicles are the result of dystrophic calcification, but the reason why this takes place is unclear. Cementicles are thought to form when calcification occurs around a nidus, a precipitating center. Around this nidus they slowly enlarge by further deposition of calcium salts. Examples of how cementicles are thought to form include:

• Calcification due to degenerative changes in the epithelial cell rests of Malassez
• Calcification of thrombosis (blocked) capillaries in the periodontal ligament (i.e. a phlebolith)
• Microtrauma to Sharpey's fibres causes small spicules of cementum or alveolar bone to splinter into the periodontal membrane
  Mosby (2013). 9780323100137, Elsevier Health Sciences. . ISBN 9780323100137
  Some do not consider these as true cementicles.