The most reliable criteria in Gustafson method of age estimation is:
Attrition
Secondary dentin deposition
Transparency of root
Cementum apposition
Ans. is 'c' i.e. Transparency of root Gustafson's method is method of age determination in adults from physiological changes in teeth.Gustafson devised a microscopic method for age estimation based on the histological examination of ground thin sections of teeth. He evaluated the correlation of six physiological changes with increasing age. These are :Attrition - d/t wear & tear from mastication, occlusal (upper) surface of the teeth is destroyed gradually, first involving the enamel, then dentin and at last the pulp.Paradentosis - with advancing age the gums and peridental tissue surrounding the teeth show regression, gradually exposing the necks, and adjacent part of root of teeth.The amount of secondary dentin - Secondary dentil deposition occurs within the pulp cavity and gradually decreases the size of the cavity.Cementum apposition - Secondary cementum is slowly and continuously deposited throughout life forming incremental lines.Age can be estimated by counting these incremental lines.The degree of root resorption Transparency of root dentine - It is the most reliable of all criteria. It is not seen before 30 yrs of age.
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