MFDS Oral Biology 2

Question 1

Which growth factor is most critical for the initiation of tooth development?

Accepted Answer

FGF-8

Answer

FGF-8 (fibroblast growth factor 8) is expressed in the oral epithelium and is one of the earliest signals initiating tooth development.

Question 2

The epithelial cell rests of Malassez are remnants of which structure?

Accepted Answer

Hertwig's epithelial root sheath

Answer

After root formation, fragments of Hertwig's epithelial root sheath persist in the periodontal ligament as the epithelial cell rests of Malassez.

Question 3

What is the approximate pH at which enamel begins to demineralise?

Accepted Answer

5.5

Answer

The critical pH for enamel demineralisation is approximately 5.5, below which the oral environment becomes undersaturated with respect to hydroxyapatite.

Question 4

Which component of saliva provides the primary antimicrobial defence against oral bacteria?

Accepted Answer

Secretory IgA

Answer

Secretory IgA is the predominant immunoglobulin in saliva and acts by aggregating bacteria and blocking their adhesion to oral surfaces.

Question 5

Which stage of tooth development is characterised by proliferation of the enamel organ into a cap shape?

Accepted Answer

Cap stage

Answer

During the cap stage the enamel organ expands and differentiates into inner and outer enamel epithelium, stellate reticulum and stratum intermedium.

MFDS Part 1 Practice Test

MFDS Part 1 Practice Test

MFDS Oral Biology 2