A. Sclerotic dentin
B. Secondary dentin
C. Reparative dentin
D. All of the above
✅ The correct answer is option B. Secondary dentin.
Oral Histology
222. The organic lining of the calcified dentinal tubules is known as_______________?
A. Lamina propria
B. Lamina lucida
C. Lamina limitans
D. Lamina densa
✅ The correct answer is option C. Lamina limitans.
223. Ameloblasts is______________?
A. A cell from which tooth enamel is formed:
B. A tissue from which tooth erupts
C. A tumour of the jaw
D. Pertaining to dentin
✅ The correct answer is option A. A cell from which tooth enamel is formed:.
224. The first sign of future deciduous teeth as a thickening of oral ectoderm appears at about_____________?
A. 25th day of Intra uterine life
B. 34th day of Intra uterine life
C. 56th day of Intra uterine life
D. 20 wks of Intra uterine life
✅ The correct answer is option C. 56th day of Intra uterine life.
225. An enzyme present in saliva which causes cell wall lysis____________?
A. Lysozhyme
B. Peroxidase
C. Lactoferin
D. Hyaluronidase
✅ The correct answer is option A. Lysozhyme.
226. Epithelial attachment is derived from____________?
A. Reduced enamel epithelium
B. Dental papilla
C. Inner enamel epithelium
D. Dental sac
✅ The correct answer is option A. Reduced enamel epithelium.
227. The plexus of Rashkov is present in which of the following zones in pulp ?
A. Cell free zone
B. Cell rich zone
C. Odontoblastic zone
D. Pulp core
✅ The correct answer is option A. Cell free zone.
228. Oral tissue for microscopic examination is prepared by_______________?
A. Embedded in paraffin and sectioned
B. Embedded in paradion and sectioned
C. Frozen and sectioned
D. Specimens ground into thin sections
✅ The correct answer is option E. All of the above.
229. The 2nd most prominent cells in pulp are______________?
A. Fibroblasts
B. defense cells
C. Odontoblasts
D. Histocytes or resting wandering cell
✅ The correct answer is option C. Odontoblasts.
230. Second arch derivatives are all except_________________?
A. Stapes
B. Malleus and incus
C. Styloid process
D. Superior part of hyoid bone
✅ The correct answer is option B. Malleus and incus.