Cementum-1

No.	Question	Answers
1	On dry weight basis, cementum has	45% to 50% inorganic substances
2	Fluoride level is highest in	Cementum
3	The major constituent of collagen in cementum belongs to	Type I collagen
4	Cementum formation occurs after	Radicular dentin formation. This occurs after the dentin deposition occurs along the inner enamel epithelium of Hertwig’s root sheath and its subsequent degeneration.
5	Cementum is formed from cells of	Dental sac
6	Cementoblasts are differentiated from	Undifferentiated mesenchymal cells
7	Breakdown of Hertwig’s epithelial root sheath involves degeneration of the basal lamina in the	Outer enamel epithelium. The basal lamina is reported to break down in the outer enamel epithelium.
8	Cementoid refers to the	Uncalcified cemental matrix
9	Connective tissue fibers embedded in to the cementum are known as	Sharpey’s fibers.
10	What are Kroff’s fibers	They are an imaginary fibers associated with dentin caused by the silver staining of ground substances.
11	Acellular cementum is not present at	Apical third of root. At the apical third of root cementum is entirely cellular type. Recent investigations point out that the classification of cementum based on cellular elements is biased. There seems to be an entirely different genotype and phenotype of cementoblasts responsible for secretion of these two types of cementum.
12	Cementum is thinnest at the	Cemento enamel junction. It is about 20 to 50 micrometer at the cementoenamel junction.
13	The maximum thickness of cementum is approximately	150 to 200 micrometers
14	Cementum is thickest at the	Apex
15	Uncalcified cementum is seen to be deposited in the	Cementodentinal junction. Though there is a layer of uncalcified cementum on the entire cementum it is in its developmental process. Uncalcified cementum is seen along the cementodentinal junction.
16	The processes of a cementocyte are generally directed to the	Periodontal surface
17	Incremental lines of cementum are	Hypermineralized areas
18	A permanent human cementodentinal junction is	Relatively smooth
19	Intermediate cementum is found in between	Dentin and cementum
20	Intermediate cementum is commonly observed in apical two thirds of	Permanent premolars and molars
21	Intermediate cementum is the area representing	Entrapped Hertwig’s epithelial sheath
22	Cementum and enamel do not meet in	10% of all teeth
23	An overlap of cementum on cervical end of enamel occurs due to	Premature loss of reduced enamel epithelium
24	When cementoblasts meet the smooth surfaces of enamel it produces	Afibrillar cementum
25	Total absence of cementum can be observed in	Hypophosphatasia
26	The function of cementum does NOT include	Self -resorption under normal condition
27	Loss of tooth substance from occlusal wear is compensated by increase in	Cementum at apex
28	Cemental hypertrophy is accompanied by	Increase in functional quality
29	In cementum hypertrophy spur can be formed in teeth that are	Exposed to great stress
30	Knob like projections of hyperplastic cementum is referred as	Excementoses
31	Extensive hyperplasia of cementum is occasionally associated with	Chronic periapical inflammation
32	Hyperplasia of cementum in nonfunctioning teeth is characterized by	A reduction in number of Sharpey’s fibers
33	Cementum differs from bone because bone is	Vascular
34	A tendency of cementum to reestablish the former outline of root surface is termed as	Anatomic repair
35	When the alveolar bone is modified to suit the functional relationship of a damaged cementum the repair is said to be	Functional repair
36	Afibrillar cementum is found at the	Cervical margin of the tooth
37	Coronal cementum is a type of	Afibrillar cementum
38	Incremental lines seen in cementum are referred to as	Incremental lines of Slater
39	The structureless, highly mineralized layer that is about 10 micrometers thick on the surface of root dentin is	Hyaline layer of Hopewell Smith. It is atubular structure with a unique organic matrix and is more mineralized than cementum or dentin. It is believed to be the tissue that cements the cementum to the dentin.
40	The first formed collagen fibrils by the cementoblasts are deposited _________ to the root surface.	In angular fashion
41	The first formed cementum is	Acellular type. As the cells forming the first formed cementum does not incorporate the cementoblasts it self and instead found on the surface the first formed cementum is acellular.
42	The function of acellular cementum is to	Provide attachment for tooth. Though all the functions described are functions of cementum, the acellular cementum maintains the anchorage part of the function and rest are performed by the cellular cementum.
43	Cementum is classified on the basis of	Time of formation; Presence of cells within the matrix; Origin of collagen fibers. Cementum can be classified on the basis of time of formation (primary or secondary), by the presence of cells within the matrix (cellular or acellular) and origin of collagen fibers (intrinsic or extrinsic)
44	The cementum that is formed before the periodontal ligament formation is	Primary acellular intrinsic fiber cementum. Explanation  Secondary cementum formation occurs after teeth eruption. Primary acellular extrinsic fiber cementum arises from the periodontal ligament only.
45	The principal tissue of attachment of the cementum is the	Primary acellular extrinsic fiber cementum
46	In some of anterior teeth the only form of cementum found is the	Primary acellular extrinsic fiber cementum
47	The degree of mineralization of the primary acellular extrinsic fiber cementum is about	60%
48	The form of cementum that is always absent in anterior teeth is the	Secondary cellular intrinsic fiber cementum. It is found only in the inter-radicular region and rarely only in apical regions.
49	The bulk of the secondary cementum is made up by the	Secondary cellular mixed fiber cementum
50	The intrinsic fibers of the cementum are arranged ________ to the root surface.	Parallel. These are fine fibered, densely packed fibers running parallel to the root surface whereas the extrinsic fibers are larger, haphazardly running and is oriented to root surfaces perpendicularly.
51	A cementum that is a developmental anomaly is	Acellular afibrillar cementum. It is limited to enamel surface as spurs close to cementoenamel junction and formed as a result of local disruption of reduced enamel epithelium.