Podcast
Questions and Answers
What is one of the primary functions of cementum?
What is one of the primary functions of cementum?
How does cementum typically change over time?
How does cementum typically change over time?
What is a notable characteristic of cementum's cellular structure?
What is a notable characteristic of cementum's cellular structure?
What implication does the relationship between the cementoenamel junction (CEJ) and cementum have?
What implication does the relationship between the cementoenamel junction (CEJ) and cementum have?
Signup and view all the answers
Which aspect of cementum is highlighted in relation to clinical implications?
Which aspect of cementum is highlighted in relation to clinical implications?
Signup and view all the answers
What is the critical pH at which hydroxyapatite crystals can start to dissolve?
What is the critical pH at which hydroxyapatite crystals can start to dissolve?
Signup and view all the answers
What is the primary type of collagen found in the organic content of cementum?
What is the primary type of collagen found in the organic content of cementum?
Signup and view all the answers
Which characteristic is associated with acellular cementum?
Which characteristic is associated with acellular cementum?
Signup and view all the answers
How much of the root surface does acellular cementum cover?
How much of the root surface does acellular cementum cover?
Signup and view all the answers
What marks the junction where acellular cementum meets dentine?
What marks the junction where acellular cementum meets dentine?
Signup and view all the answers
Which type of cementum continues to form throughout the lifecycle of the tooth?
Which type of cementum continues to form throughout the lifecycle of the tooth?
Signup and view all the answers
What is the main characteristic of afibrilar cementum?
What is the main characteristic of afibrilar cementum?
Signup and view all the answers
Which component is NOT typically found in the organic content of cementum?
Which component is NOT typically found in the organic content of cementum?
Signup and view all the answers
What is the primary function of acellular extrinsic fibers cementum (AEFC)?
What is the primary function of acellular extrinsic fibers cementum (AEFC)?
Signup and view all the answers
Where is acellular afibrillar cementum (AAC) primarily located?
Where is acellular afibrillar cementum (AAC) primarily located?
Signup and view all the answers
What type of fibers are primarily found in cellular cementum?
What type of fibers are primarily found in cellular cementum?
Signup and view all the answers
Which component forms the attachment between cementum and the periodontal ligament?
Which component forms the attachment between cementum and the periodontal ligament?
Signup and view all the answers
What describes the characteristics of acellular afibrillar cementum (AAC)?
What describes the characteristics of acellular afibrillar cementum (AAC)?
Signup and view all the answers
Which type of cementum forms more rapidly than primary cementum?
Which type of cementum forms more rapidly than primary cementum?
Signup and view all the answers
What is cemetogenesis?
What is cemetogenesis?
Signup and view all the answers
What substance may be found at the periphery of cellular cementum?
What substance may be found at the periphery of cellular cementum?
Signup and view all the answers
Which of the following statements about acellular cementum is true?
Which of the following statements about acellular cementum is true?
Signup and view all the answers
What is the orientation of extrinsic fibers in acellular extrinsic fibers cementum?
What is the orientation of extrinsic fibers in acellular extrinsic fibers cementum?
Signup and view all the answers
What are cementocytes derived from?
What are cementocytes derived from?
Signup and view all the answers
In which area is cellular intrinsic fiber cementum primarily found?
In which area is cellular intrinsic fiber cementum primarily found?
Signup and view all the answers
What is the primary function of cellular cementum?
What is the primary function of cellular cementum?
Signup and view all the answers
Which type of cellular cementum contains both intrinsic and extrinsic fibers?
Which type of cellular cementum contains both intrinsic and extrinsic fibers?
Signup and view all the answers
Why is cellular cementum thicker in posterior teeth?
Why is cellular cementum thicker in posterior teeth?
Signup and view all the answers
Which of the following statements about cellular intrinsic fiber cementum is false?
Which of the following statements about cellular intrinsic fiber cementum is false?
Signup and view all the answers
What is one of the roles of deposits of cementum at the apex of teeth?
What is one of the roles of deposits of cementum at the apex of teeth?
Signup and view all the answers
Cellular cementum is least likely to be found in which type of tooth?
Cellular cementum is least likely to be found in which type of tooth?
Signup and view all the answers
What structure embeds cementocytes in cellular cementum?
What structure embeds cementocytes in cellular cementum?
Signup and view all the answers
What is the primary role of cellular cementum in relation to periodontal disease?
What is the primary role of cellular cementum in relation to periodontal disease?
Signup and view all the answers
Where is acellular cementum primarily located in relation to the tooth structure?
Where is acellular cementum primarily located in relation to the tooth structure?
Signup and view all the answers
Which factor is NOT associated with hypercementosis?
Which factor is NOT associated with hypercementosis?
Signup and view all the answers
How does cementum thickness change with age?
How does cementum thickness change with age?
Signup and view all the answers
What percentage of the CEJ is characterized by 'overlap' among teeth?
What percentage of the CEJ is characterized by 'overlap' among teeth?
Signup and view all the answers
What occurs during anatomical repair of cellular cementum?
What occurs during anatomical repair of cellular cementum?
Signup and view all the answers
What is hypercementosis primarily characterized by?
What is hypercementosis primarily characterized by?
Signup and view all the answers
The distribution of cementum in teeth is affected by which factor?
The distribution of cementum in teeth is affected by which factor?
Signup and view all the answers
What is the consequence of cementum continuously forming throughout life?
What is the consequence of cementum continuously forming throughout life?
Signup and view all the answers
What is a common clinical implication of hypercementosis?
What is a common clinical implication of hypercementosis?
Signup and view all the answers
Study Notes
Composition
- Cementum is composed of two main components: inorganic material (45-50%) and organic material (50-55%)
- Hydroxyapatite crystals make up the inorganic portion of cementum.
- Cementum begins to dissolve at a critical pH of 6.7
- Collagen fibers are the primary component of the organic material.
- Types I, III, V, VI, XII, and XIV collagen fibers are found in cementum.
- Non-collagenous matrix proteins and water also contribute to cementum's organic content.
Structural Features
- Cementum is classified based on cell presence and fiber type.
- Acellular cementum lacks cells and is typically formed first (primary cementum).
- Cellular cementum contains cementocytes and is formed later (secondary cementum).
- Extrinsic fibers are connected to the periodontal ligament (PDL) and alveolar bone.
- Intrinsic fibers are embedded within the cementum and run parallel to the root surface.
- Acellular afibrillar cementum (AAC) contains no collagen fibers and is found in the cervical region.
- Acellular extrinsic fibers cementum (AEFC) is the most common type of acellular cementum.
- Cellular intrinsic fiber cementum (CIFC) is found in the apical third of roots and interradicular regions.
- Cellular mixed stratified cementum (CMSC) contains both intrinsic and extrinsic fibers.
Acellular Cementum: Functions and Location
- Acellular cementum primarily functions in support and anchorage.
- Extrinsic fibers embed into cementum and alveolar bone, creating Sharpey's fibers that contribute to tooth anchorage.
- Acellular cementum is mainly concentrated in the cervical and middle third of the root, covering 40-70% of the root surface.
Cellular Cementum: Functions and Location
- Cellular cementum forms quickly compared to acellular cementum.
- This process involves cementoblasts, which originate from the dental sac and form cementum through cementogenesis.
- Cementoblasts become trapped in the matrix, transforming into cementocytes.
- Cementoid, an unmineralized matrix, is present at the periphery of cellular cementum.
- Intrinsic fibers are parallel to the root surface and may be joined by extrinsic fibers over time.
- Cellular cementum is primarily located in the apical third of the root and interradicular regions.
Cellular Cementum Functions: Adaption and Repair
- Cellular cementum allows for adaption and repair of the root surface in response to changing needs.
- This includes reshaping the root for tooth movement and deposition of cementum at the apex to compensate for occlusal wear.
- Cellular cementum can also repair resorbed or fractured root surfaces.
Distribution of Cementum
- There is a distinct pattern of cementum distribution along the root:
- Acellular cementum (AEFC) predominates in the cervical region.
- Cellular cementum (CMSC and CIFC) dominates in the apical region.
- Cementum thickness varies based on the type of tooth and its location within the mouth.
Cementum over the Lifecourse
- Cementogenesis continues throughout life.
- Cementum thickens, hardens, and increases in mineral content with age.
Cemento-Enamel Junction (CEJ)
- The CEJ, where cementum and enamel meet, can have different relationships:
- Overlap (most common): cementum covers enamel.
- Gap: a space exists between cementum and enamel.
- Meet: cementum and enamel are juxtaposed.
Structural Abnormalities - Hypercementosis
- Hypercementosis, an excessive deposition of cementum at the apex, can result in thicker roots.
- Possible causes include local factors (trauma or inflammation) and systemic factors (Paget's disease) or unknown causes.
- Clinical implications:
- Can affect single or multiple teeth.
- May cause problems during tooth extraction.
Summary
- Acellular and cellular cementum differ in cell presence and fiber types, contributing to distinct functions.
-
Functions of Cementum:
- Anchorage and support
- Adaptation
- Repair
-
Clinical Implications:
- Continued growth and deposition throughout life
- Variations in CEJ relationships
- Potential for abnormalities such as hypercementosis
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Related Documents
Description
This quiz explores the composition and structural features of cementum, focusing on its inorganic and organic components, types of collagen fibers, and the classifications based on cell presence and fiber type. Understand the differences between acellular and cellular cementum and their roles in dental anatomy.