CDT Dental Lab Quality Management 2 — Questions and Answers
Question 1: Which document serves as the primary reference for establishing a dental laboratory quality management system in the United States?
- ISO 13485:2016 (Correct answer)
- ANSI/ADA Specification 25
- OSHA 29 CFR 1910.1030
- FDA 21 CFR Part 820
Correct answer: ISO 13485:2016
ISO 13485:2016 specifies requirements for a quality management system for organizations involved in the design and manufacture of medical devices, including dental prosthetics.
Question 2: A dental lab receives a crown back from the dentist because the margin is open. Which corrective action step should come FIRST?
- Retrain the technician immediately
- Document the nonconformance in the complaint log (Correct answer)
- Remake the crown without investigation
- Contact the patient directly
Correct answer: Document the nonconformance in the complaint log
Documenting the nonconformance is the first step in any corrective action process to ensure traceability and proper root cause analysis.
Question 3: What is the purpose of a 'design history file' (DHF) in a dental laboratory producing custom appliances?
- To track employee training records
- To document the design and development process for regulatory compliance (Correct answer)
- To record daily equipment calibration
- To maintain patient payment histories
Correct answer: To document the design and development process for regulatory compliance
A design history file documents the design and development process to demonstrate that the device was developed in accordance with the approved design plan.
Question 4: A technician notices that a batch of alloy from a new supplier has inconsistent color after casting. What QMS tool should be used to identify the root cause?
- Pareto chart
- Gantt chart
- Control chart
- Fishbone (Ishikawa) diagram (Correct answer)
Correct answer: Fishbone (Ishikawa) diagram
A fishbone diagram systematically maps potential causes across categories such as materials, methods, machines, and manpower to identify root causes.
Question 5: Under FDA regulations, which type of dental prosthetic is classified as a Class II medical device requiring 510(k) clearance?
- Removable partial denture frameworks (Correct answer)
- Temporary resin crowns fabricated chairside
- Patient-matched bone plates
- Preformed orthodontic brackets
Correct answer: Removable partial denture frameworks
Removable partial denture frameworks are classified as Class II devices under 21 CFR Part 872 and require 510(k) clearance before marketing.
Question 6: Which statistical process control (SPC) chart is BEST suited for monitoring the proportion of defective units in a dental lab production run?
- X-bar and R chart
- p-chart (Correct answer)
- c-chart
- CUSUM chart
Correct answer: p-chart
The p-chart (proportion defective chart) monitors the fraction of nonconforming units in subgroups and is ideal for attribute data such as pass/fail inspection.
Question 7: When a dental lab undergoes an FDA inspection, which record must be available to demonstrate control of nonconforming products?
- Employee payroll records
- Nonconformance reports with disposition records (Correct answer)
- Marketing and pricing records
- Dental school affiliation certificates
Correct answer: Nonconformance reports with disposition records
FDA 21 CFR Part 820.90 requires documented procedures for control of nonconforming product, including identification, documentation, evaluation, and disposition.
CDT Dental Lab Quality Management 2
Which document serves as the primary reference for establishing a dental laboratory quality management system in the United States?