Overview
All-on-X configurations—whether four, five, six, or more implants supporting a dental full arch dental prosthesis—demand rigorous position verification before dental framework fabrication. The increasing complexity of multi-implant arrays means small positional errors compound exponentially. A dental framework designed for six incorrectly positioned analogs has six opportunities for misfit.
What You'll Need
- verification jig (resin or metal) representing your dental master cast
- Hex drivers compatible with your dental prosthetic components
- Calibrated torque wrench
- explorer and magnification
- Articulating paper or fit checking material
- Documentation forms for verification records
Step-by-Step
Assess the dental verification jig
Examine your dental verification jig for damage, distortion, or contamination. Resin jigs may deform over time; metal jigs may have loosened connections. Clean all coping interfaces with isopropyl alcohol.
Prepare the Patient
Remove the existing dental prosthesis and clean all implant or multi-unit dental abutment interfaces. Debris mimics positional discrepancy. Verify that all dental abutments are properly torqued and stable.
Seat the dental verification jig
Place the jig over the implants/dental abutments and allow it to settle passively without any screw engagement. All copings should engage their implant connections simultaneously.
Perform Sheffield Testing - First Position
Select the most distal implant on one side. Thread and fully torque the dental prosthetic screw at this single position only. Examine every other implant-coping interface for gaps using explorer and magnification.
Evaluate Gap Patterns
A truly accurate system shows zero detectable gap at any non-torqued position. Gaps at multiple positions suggest systematic dental master cast error. A gap at one position only might indicate localized analog misposition.
Release and Repeat - Opposite Side
Remove torque from the first position. Select the most distal implant on the opposite side and apply torque. Repeat interface examination.
Test from Anterior Position
For comprehensive verification, repeat the Sheffield test with torque applied to an anterior implant. This configuration stresses the jig differently.
Apply Disclosing Medium
For subtle discrepancies, apply fit checking material to all coping interfaces. Seat the jig, tighten one screw, and allow to set. Examine contact patterns.
Compare to dental master cast
Perform identical Sheffield testing with the dental verification jig on your dental master cast. The fit should match clinical findings.
Document and Decide
Record all verification findings. If the jig passes clinical Sheffield testing and fits identically on the dental master cast, proceed to dental framework fabrication.
Tips & Best Practices
- Perform verification at a dedicated appointment rather than squeezing it into other procedures
- Use the same torque values consistently across all testing for comparable results
- Consider photographic documentation of verification results
- When in doubt, verify twice—the cost of double-checking is trivial compared to dental framework failure
Common Mistakes to Avoid
Tightening multiple screws
Each additional screw draws the jig toward seating, masking misfit. Only one screw may be engaged during Sheffield testing.
Skipping the dental master cast comparison
Clinical fit alone doesn't confirm cast accuracy. The jig must fit both patient and cast identically.
Proceeding despite marginal results
"Almost passive" fit becomes dental framework misfit. Demand zero detectable gaps before authorizing fabrication.