Which in tubules may be affected even if acids do not reach the pulp?

• A. Nerve fibers
• B. Odontoblastic processes
• C. Blood vessels
• D. Dentin tubule sclerosis

Answer: (B)

Odontoblastic processes extend into dentinal tubules, creating a living interface between the dentin and the oral environment. Because these processes lie inside the tubules, they can be exposed to chemical stimuli that diffuse through dentin even when the irritant hasn’t reached the pulp. Acids or demineralizing agents can interact with and affect these odontoblastic processes within the tubules, potentially causing cytotoxic or functional changes, while the pulp itself remains unaffected. In contrast, nerve fibers and blood vessels reside in the pulp, not within the tubules, so they’re not directly impacted inside tubules when acids don’t reach the pulp. Dentin tubule sclerosis is a defensive change that reduces tubule permeability, so it isn’t the target of damage in this scenario.