Dental X-Ray Exposure Reference Chart
General guidance — always follow your unit manufacturer's settings
Unit-specific settings take precedence
Always use your X-ray unit manufacturer's recommended exposure settings as the primary reference. These values are general guidance. Individual unit calibration, digital sensor type, film speed, and technique all affect the appropriate exposure.
| Radiograph Type | Patient | kV | mA | Time (sec) | Impulses | Dose (μSv) | Notes |
|---|---|---|---|---|---|---|---|
| Periapical Radiographs (Digital Sensor) | |||||||
| Periapical - anterior | Adult | 65 kV | 7 mA | 0.06-0.10 | 3-5 | 1-3 μSv | Reduce 20-30% vs film |
| Periapical - posterior | Adult | 65 kV | 7 mA | 0.10-0.16 | 5-8 | 2-5 μSv | More tissue to penetrate |
| Periapical - anterior | Child | 60 kV | 7 mA | 0.04-0.06 | 2-3 | <2 μSv | Reduce 50% vs adult |
| Periapical - posterior | Child | 60 kV | 7 mA | 0.06-0.10 | 3-5 | 1-3 μSv | Thyroid collar essential |
| Bitewing Radiographs (Digital Sensor) | |||||||
| Posterior bitewing | Adult | 65 kV | 7 mA | 0.10-0.14 | 5-7 | 2-4 μSv | Standard adult bitewing |
| Posterior bitewing | Child | 60 kV | 7 mA | 0.06-0.10 | 3-5 | 1-3 μSv | Thyroid collar required |
| Periapical Radiographs (D-Speed Film — reference only) | |||||||
| Periapical - posterior | Adult | 65 kV | 10 mA | 0.32-0.48 | 16-24 | 5-10 μSv | Film requires longer exposure |
| Periapical - posterior | Adult | 70 kV | 10 mA | 0.24-0.32 | 12-16 | 4-8 μSv | Higher kV = longer contrast scale |
| Radiograph Type | Patient | kV Range | mA Range | Dose (μSv) | Notes |
|---|---|---|---|---|---|
| Panoramic Radiographs | |||||
| Panoramic (OPG) | Adult | 60-80 kV | 4-15 mA | 14-24 μSv | Automatic exposure control on most units. Follow manufacturer program settings. |
| Panoramic (OPG) | Child | 60-70 kV | 4-10 mA | 8-15 μSv | Use child program if available. Thyroid shield where possible. |
| Panoramic - TMJ | Adult | 60-80 kV | 4-15 mA | 14-24 μSv | May require separate TMJ program on unit. |
| Cephalometric Radiographs | |||||
| Lateral cephalogram | Adult/Teen | 70-80 kV | 10-15 mA | 3-6 μSv | Requires cephalostat attachment. Lead apron essential. |
| Posterior-anterior ceph | Adult/Teen | 70-80 kV | 10-15 mA | 3-6 μSv | For facial asymmetry assessment. |
| Cone Beam CT (CBCT) | |||||
| CBCT - small FOV (<5cm) | Adult | 80-90 kV | 4-8 mA | 20-100 μSv | Single tooth/implant site. Low-dose protocols available. |
| CBCT - medium FOV (5-10cm) | Adult | 85-100 kV | 6-10 mA | 50-300 μSv | One arch. Most implant planning uses this FOV. |
| CBCT - large FOV (>10cm) | Adult | 85-120 kV | 8-15 mA | 300-1000 μSv | Full facial skeleton. Justify carefully. Use lowest dose protocol. |
| Patient Type | Adjustment vs Standard Adult | Clinical Notes |
|---|---|---|
| Small adult / thin build | Reduce 20-30% | Reduce mA or impulses. Keep kV same for contrast. |
| Standard adult | Baseline | Use unit manufacturer's standard adult settings. |
| Large/dense build | Increase 20-40% | Increase mA or impulses. Consider raising kV by 5 kV. |
| Child (5-10 years) | Reduce 50% | Use child program. Thyroid collar always. Consider if radiograph is necessary. |
| Child (10-14 years) | Reduce 25-35% | Approaching adult dentition. Thyroid collar. Justify each exposure. |
| Edentulous patient | Reduce 25% | Less tissue density. Reduce time/mA. Consider if panoramic adequate. |
| Exposure Source | Dose (μSv) | Equivalent To |
|---|---|---|
| 1 periapical (digital) | 1-3 μSv | ~1 hour of background radiation |
| 4 bitewings (digital) | 4-8 μSv | ~1 day of background radiation |
| Full mouth series (digital) | 35-170 μSv | ~1-3 weeks of background radiation |
| Panoramic radiograph | 14-24 μSv | ~2-4 days of background radiation |
| Small-volume CBCT | 20-100 μSv | ~3 days-2 weeks of background radiation |
| Large-volume CBCT | 300-1000 μSv | ~6 weeks-5 months of background |
| Daily background radiation | 6.6 μSv/day | Annual total ~2,400 μSv |
| Transatlantic flight | 50-80 μSv | Equivalent to ~full mouth series |
ALARA and justification in dental radiography
The ALARA principle (As Low As Reasonably Achievable) underpins all dental radiation protection. Every exposure must be justified - the clinical benefit must outweigh the radiation risk. For low-risk patients, routine radiographs should not be taken on a fixed schedule but based on clinical need. The FDA/ADA selection criteria provide evidence-based guidance on radiograph frequency by patient risk category.
Digital sensors (PSP plates and solid-state sensors) require approximately 50-80% less radiation than F-speed film to produce a diagnostic image. This makes the remaining use of D or E-speed film difficult to justify. Rectangular collimation reduces radiation dose by approximately 50% compared to round collimation and is strongly recommended for periapical and bitewing radiographs.
For clinical documentation involving radiograph findings, see our CDT Code Lookup Tool for the correct radiograph billing codes (D0210-D0364). For sterilization and infection control records related to radiograph equipment, use our Sterilization Log.
Frequently Asked Questions
Most modern dental X-ray units use 60-70 kV for periapical radiographs. Higher kV (65-70 kV) produces a longer scale of contrast with less patient dose but slightly lower contrast images. Lower kV (60-65 kV) produces higher contrast but slightly higher dose. Digital sensors allow lower exposure times than film, so the combination of 65 kV, 7 mA, and 0.06-0.16 seconds is common for adult periapical radiographs with digital sensors.
A full mouth series using modern digital receptors delivers approximately 35-170 microsieverts (μSv). For comparison, background radiation from the environment is approximately 2,400 μSv per year (about 6.6 μSv per day). A panoramic radiograph delivers approximately 14-24 μSv. CBCT varies widely by field of view: small-volume CBCT delivers 20-100 μSv, large-volume CBCT delivers 300-1000 μSv.