Cementum
Upcoming SlideShare
Loading in...5
×
 

Cementum

on

  • 2,274 views

 

Statistics

Views

Total Views
2,274
Views on SlideShare
2,274
Embed Views
0

Actions

Likes
2
Downloads
86
Comments
0

0 Embeds 0

No embeds

Accessibility

Upload Details

Uploaded via as Microsoft PowerPoint

Usage Rights

© All Rights Reserved

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
    Processing…
Post Comment
Edit your comment

Cementum Cementum Presentation Transcript

  • GOOD MORNING
  • CEMENTUM
  • DEFINITION Cementum is the calcified a vascular mesenchmal tissue that forms the outer layer cover of the anatomic root Types of cementum There are two main types of cementum they are:- 1.A celluar cementum and 2.cellular cementum The two main source’s of collagen fibers in cementum are sharpey’s fibers which are the embedded portion of principal fibers of the
  •  Periodontal ligament and are formed by the fibroblasts Fibers that belong to cementum matrix and are produced by cementoblasts Cementoblasts also form the non collagenous components of the inter fibrillar ground substance such as proteoglycans, glycoproteins and phosphoproteins Proteoglycans are the most likely to play a role in regulating cell-cell and cell-matrix interactions
  •  COMPOSTION The major proportion of the organic matrix of a cementum is composed of type one (90%) and type three about (5%) collagens ACELLULAR CEMENTUM It is the first cementum formed, covers approximately the cervical third or half of the root and does not contain cell’s
  •  This cementum is formed before the tooth reaches the occlusal plane and it’s thickness ranges froms 30 to 230 um Sharpey’s fibers are completely calcified, with the mineral crystals. Oriented parallel to the fibrils as dentin and bone except in a 10 -50 um wide zone near the cementodentinal junction where they are only partially calcified
  •  Acellular cementum also contains intrinsic collagen fibrils that are calcified and irregularly arranged or parallel to the surface CELLULAR CEMENTUM Celluar cementum formed after the tooth reaches the occlusal plane is more irregular and contain cell’s (cementocytes) in individual spaces (lacunae)
  • that communicate with each other through a system of anastomising canaliculi Cellular cementum is less calcified than the acellular type Sharpey’s fibers occupy a smaller portion of cellular cementum and are separated by other fibers that are arranged either parallel to the root surface Both acellular and cellular cementum are aranged in lamellae separated by incremental lines parallel to long axis root this lines are called rest periods
  •  PERMEABILITY OF CEMENTUM In very young animal’s acellular cementum and cellular cementum are very permeable and permit the diffusion of dyes from the pulp and external root suface THICKNESS OF CEMENTUM Cementum deposition is a continuous process that proceeds at varying rates
  •  Cementum formation is most rapid in the apical regions where it compensates for tooth eruption, which it self compensate for attrition The thickness of cementum on the coronal half of the root varies from 16-60um It attains greatest thickness (upto 150-200 um) in the apical third and in the fraction areas Abnormalities in the thickness of cementum may range from an absence of cellular cementum to an excessive deposition of cementum
  •  The term hyper cementosis refers to a prominent thickening of cementum Hyper cementosis occurs a generalisied thickening of the cementum CEMENTUM RESORPTION AND REPAIR Cementum resorption may be caused by local and systemic factors
  •  Local condition causing cementum resorption include trauma from occlusion orthodontic movement pressure from malaligned erupting teeth cysts and tumors teeth with out junctional antagoinsts Systemic condition citied as predisposing to or including cemental resorption include calcium deficiency hypothyroidism, hereditary fibrous osteodystrophy
  •  EXPOSURE OF CEMENTUM TO ORAL ENVIRONMENT Cementum becomes exposed to the oral environment in cases of gingival recession and as result of loss of attachment in pocket formation CEMENTO ENAMEL JUNCTION The cementum at and immediately subjacent to cemento enamel junction is of particular clinical importance in root scaling procedures
  •  Three types of relationships involving the cementum may exists at cementoenamel junction in about 60 -65% of cases, cementum over laps the enamel in about 30% an edge-edge but joint exists and 5-10% the cementum and enamel fail to meet CEMENTO DENTINAL JUNCTION The terminal apical area of cementum where it joins the internal root canal dentin is known as cemento dental junction
  • THANK YOU GUIDED BYDR. KRISHNA MOORTHY. MDSDR. ROOPA DEVI. MDSDR. RAVEENDHAR REDDY. MDSDR. SHARATH. MDSDR.VENKAT SUBBA REDDY. MDS SUBMITTED BYDR. PRADEEP. MDS N.V.GAYATRI SAROJINI IV BDS