Understanding the "95% Unsatisfactory Rate"
The figure "95% of occlusal scans are unsatisfactory" comes from the well-known podcast Digital Dentistry Decoded. "Unsatisfactory" does not mean the bite data is completely unusable. It means the data still requires optimization - for example, technicians must manually adjust the occlusion in software or make "best-guess" decisions to complete the restoration design.
Why Do Occlusal Scans Fall Short?
Device and Software Hard Limitations
Inherent differences between scanner systems Accuracy of occlusal scanning varies significantly across brands and models of intraoral scanners.
Accumulation of stitching errors Intraoral scanning works by capturing hundreds of consecutive 2D images and stitching them together like a puzzle. Small errors accumulate as the full arch is scanned, eventually producing measurable deviation. This has limited impact on small-area scans but becomes problematic in full-arch or implant cases.
Lack of calibration or optical path contamination Dirty probe lenses, worn scan tips, or long-term failure to calibrate directly degrade data quality. Some scanners may also experience scan-head sensor faults that prevent normal calibration.
Patient Factors
Unstable occlusion Patients may unconsciously move the mandible during scanning, or they may already have occlusal instability, making the recorded bite relationship unreliable.
Multiple missing teeth This is a well-documented accuracy killer. When two or more teeth are missing, occlusal scan accuracy drops markedly. Smooth gingival surfaces in edentulous areas lack distinctive features, so the software struggles to find stable matching references. The larger the edentulous span, the worse the accuracy.
Periodontal ligament elasticity Teeth are not rigid bodies. Under load, the periodontal ligament allows micro-movement. This physiological difference between the scan and the final restoration can contribute to occlusal discrepancies.
Operator Technique - Usually the Decisive Factor
Insufficient buccal data capture (most common) The "anchor points" for aligning upper and lower arches come from matching buccal tooth surfaces. If only the buccal cusp tips are scanned without adequate buccal surface morphology, the software lacks enough data for correct alignment. Recommendation: Capture 2–3 teeth on each side, preferably in the more stable posterior region, and record both left and right sides.
Soft-tissue interference Smooth gingival surfaces lack clear features. Excess buccal or lingual mucosa and soft tissue around the maxillary tuberosity can "trick" the algorithm into incorrect stitching.
Improper occlusal posture When the patient is lying down, the posterior mandible naturally tends to retrude, leading to inaccurate bite recording. Confirm the correct occlusal relationship first, stabilize the mandible with your hand if necessary, then begin scanning.
Wrong scanning timing Starting the scan before the patient has fully closed, or withdrawing the scanner before stitching is complete, results in incomplete data.
Foreign material or liquid interference Saliva, blood, or other residues on the occlusal surfaces can be misinterpreted by the software as part of the tooth, artificially raising the occlusal surface.
Improper implant scan-body technique Scanning the occlusion while tall scan bodies are still in place can cause the opposing teeth to contact the scan body. The software then treats that contact as the true occlusal stop, resulting in a restoration that is too high.
Systematic Solutions
01. Addressing the Scanner Itself
Accept and compensate for inherent error. Do not expect perfection from a single scan. Use the scanner's occlusion-verification function (if available) to compare multiple bite positions.
Record bilateral occlusion: scan 2–3 posterior teeth on both left and right sides. The software can cross-validate the two sides and reduce matching error.
Prefer scanners that offer a continuous occlusion-scanning mode, which captures multiple frames while the patient bites lightly rather than relying on a single snapshot.
02. Addressing the Operator (Where the Biggest Improvement Occurs)
Ensure tooth surfaces are dry and free of saliva or blood.
Remove scan bodies in implant cases before recording the occlusion.
Position the patient sitting upright or lying with the mandible not retruded.
After scanning both arches, have the patient close into occlusion and stabilize the mandible with your hand.
Scan the occlusion side by side (left posterior → right posterior), capturing 2–3 teeth per side and stopping once stitching is successful.
Review the data in real time: rotate the 3D model, check that buccal gingival margins are clear and that contact points appear continuous. Rescan immediately if obvious steps or gaps are present.
Regularly request "occlusion scan quality feedback" from the laboratory. Technicians can see which data required manual offset and help you refine your technique.
03. Addressing the Patient (Solving the Largest Variable)
Pre-scan communication: demonstrate what "gently close on the back teeth, no force, no protrusion or lateral shift" means.
Have the patient practice the stable, comfortable bite position 2–3 times before scanning.
Special situations:
Anesthetized patients: wait until anesthesia partially wears off, or use silicone bite registration material as an intermediary.
Painful patients: resolve acute pain first or scan only the contralateral side.
Elderly or cognitively impaired patients: involve a caregiver or switch to extra-oral bite registration (traditional silicone + model scanning followed by registration).
Physical aids: have the patient bite on a dedicated occlusal registration resin block and scan the imprint on the block rather than the direct tooth contacts. This markedly reduces error caused by patient instability.
Summary
The fact that 95% of occlusal scans are suboptimal is not primarily because the equipment is inadequate. It results from the combination of inherent scanner matching error + non-standardized operator technique + patient non-cooperation.
The real solution is not simply buying a more expensive scanner. The effective approach is to:
Acknowledge that error is inevitable and use bilateral verification to offset it,
Standardize the clinical workflow to reduce operator variables,
Use pre-communication and physical aids to convert patient uncertainty into controllable factors,
Close the loop with laboratory feedback so that residual deviation is reduced to a clinically acceptable range.
At Aident Technology we design our intraoral scanners and digital workflows with practical occlusion-recording challenges in mind - supporting clear bilateral data capture, stable stitching, and real-time quality checks - so clinics can achieve more reliable bite registrations and reduce the need for manual laboratory corrections.
