ORE Part 1 Dental Anatomy and Histology

Question 1

Which permanent tooth has the longest root in the human dentition?

Accepted Answer

Upper canine

Answer

The maxillary canine has the longest root of any tooth in the human dentition. Its long, robust root provides excellent anchorage, which is why canines are often the last teeth to be lost in the ageing dentition and serve as important abutments in prosthodontics.

Question 2

What is the Tome's process associated with?

Accepted Answer

Ameloblasts secreting enamel matrix

Answer

Tome's process is a cytoplasmic extension of the ameloblast cell that is responsible for secreting the enamel matrix during the secretory stage of amelogenesis. The shape and orientation of Tome's processes determine the characteristic rod and inter-rod pattern of mature enamel.

Question 3

How many root canals does a mandibular first molar typically have?

Accepted Answer

Three

Answer

The mandibular first molar typically has two roots (mesial and distal) with three root canals — two in the mesial root (mesiobuccal and mesiolingual) and one in the distal root. However, a second distal canal is found in approximately 30% of cases, making four canals common.

Question 4

Which type of dentine is formed as a physiological response throughout life?

Accepted Answer

Secondary dentine

Answer

Secondary dentine is deposited slowly and continuously by odontoblasts throughout the life of a vital tooth, after root formation is complete. This gradually reduces the size of the pulp chamber. Tertiary dentine, by contrast, is formed as a pathological response to stimuli such as caries or attrition.

Question 5

The Hunter-Schreger bands seen in enamel are caused by which structural feature?

Accepted Answer

Changes in direction of enamel rod groups

Answer

Hunter-Schreger bands are alternating light and dark bands seen in enamel under reflected light. They are caused by changes in direction (decussation) of groups of enamel rods, which creates zones that reflect light differently. This arrangement increases enamel's resistance to crack propagation.

ORE Part 1 Practice Test

ORE Part 1 Practice Test

ORE Part 1 Dental Anatomy and Histology