DH170 – Dental Hygiene Key Concepts and Mechanisms – 2025/2026 – 30 Exam Questions on Hypersensitivity, Diagnosis, Oral Lesions & Biofilm

This document includes 30 high-yield exam questions and correct answers for DH170 – Dental Hygiene Key Concepts and Mechanisms for the 2025/2026 academic year. It provides an essential summary of clinical mechanisms and diagnostic insights every dental hygiene student should master. The questions cover critical areas such as the hydrodynamic theory of hypersensitivity, types and causes of enamel loss, and common desensitizing agents like 5% potassium nitrate. It also reviews the Dental Hygiene Process of Care, legal standards for record retention in Ontario, the distinction between medical consultation and clearance, and protocols for informed refusal. Special focus is given to extra/intraoral examination (EOE/IOE) findings, identification of macules, and high-risk areas for oral cancer. The document also explores the progression of oral biofilm to calculus, identification of subgingival calculus, proper instrument selection like the 11/12 explorer, and stain management including selective polishing and safe ultrasonic scaling. This resource is especially useful for: Dental Hygiene students preparing for written exams or OSCEs Dental Assisting students needing conceptual clarity on oral pathology and diagnostics Learners reviewing for clinical assessments involving charting, biofilm analysis, or lesion detection Keywords: DH170, hypersensitivity, dental hygiene diagnosis, enamel erosion, potassium nitrate, client records, oral cancer screening, macule, biofilm stages, calculus detection, 11/12 explorer, chlorhexidine stain, selective polishing, ultrasonic scaling, DH process of care