Overview
EN ISO 3823-1:1998 (ISO 3823-1:1997) specifies requirements for dental rotary instruments - burs, focusing on steel and carbide burs. The standard defines permitted shapes, dimensions, shank types, performance limits and test methods to ensure safety, interchangeability and functional performance of burs used in dentistry.
Key topics and technical requirements
- Shapes and dimensions: Detailed dimensional tables and permitted tolerances for common head shapes (round, inverted cone, pear, straight/tapered fissure, wheel, cross‑cut variants) and nominal diameters.
- Shank types: Shank shall conform to Type 1, 2 or 3 per ISO 1797.
- Run‑out (radial runout): Maximum total indicated run‑out is specified:
- Steel burs: 0.08 mm
- Carbide burs: 0.05 mm
Measurement procedures referenced to ISO 8325.
- Corrosion resistance: If declared corrosion‑resistant, burs must show no signs of corrosion or functional deterioration after autoclave testing (non‑vacuum autoclave at 134–138 °C and 0.22 MN·m‑2 / 2.2 bar). Slight galvanic corrosion at the carbide/neck junction is permitted.
- Neck strength: After corrosion testing, the instrument shall not fracture or take a permanent set exceeding:
- Steel burs: 0.08 mm
- Carbide burs: 0.05 mm
Test loads for specific head types and nominal diameters are provided in the standard’s tables.
- Testing procedures: Measurement and test methods (shapes/dimensions, run‑out, corrosion, neck strength) are specified, with reference to ISO 8325 and related methods.
- Quality control & AQL:
- Sampling: batches tested with sample sizes of 100–150 burs, including at least 20 burs of each of ≥5 sizes and all shank types.
- Acceptance: check 20 burs per defect type; accept if ≤3 failures; ≥4 failures = non‑compliant.
- Acceptable Quality Level (AQL): 6.5 max defects per 100 pieces.
- Labelling & packaging: Minimum package labelling requirements (manufacturer/trademark, working material, shank type, shape number, size, lot number, “sterile” if applicable). Packaging otherwise at manufacturer’s discretion.
Applications and target users
- Dental instrument manufacturers and product designers - for design, production tolerances and performance verification.
- Quality control and testing laboratories - to perform run‑out, corrosion and neck strength tests and sampling plans.
- Regulatory and procurement teams - to verify conformity of burs for clinical use and supply specifications.
- Dental device auditors and compliance managers - to establish acceptance criteria and labelling requirements.
Related standards
- ISO 1797 - shank types
- ISO 8325 - measurement/test methods for dental rotary instruments
- ISO 3696 - water purity for testing
- ISO 6360 - labelling recommendations
Keywords: dental rotary instruments, burs, steel burs, carbide burs, ISO 3823-1, run‑out, corrosion resistance, neck strength, shank types, AQL, dental instrument standards.