Overview
Splinting impression copings is the critical step that separates accurate dental full arch impressions from dental framework disasters. Without rigid connection between copings, each fixture transfers independently during impression removal, allowing microscopic shifts that compound into macroscopic misfit. The challenge lies in achieving true rigidity while managing the polymerization shrinkage inherent in conventional resin splinting methods.
What You'll Need
- Impression copings seated on all implants
- floss or orthodontic wire
- Pattern resin or light-cured composite
- Sectioning disc and slow-speed handpiece
- Low-shrinkage reluting material
- Alternatively: dental implant verification jig kit
Step-by-Step
Plan Your Splint Configuration
Assess the arch geometry and dental implant positions. For four implants, create a rigid dental framework connecting all four points. For six or more implants, consider additional cross-arch connections for maximum stability. Visualize the splint path to ensure it won't interfere with impression tray seating or material flow.
Create the Primary Connection (Floss/Wire Method)
Wrap dental floss or orthodontic wire around each impression coping, creating taught connections between adjacent copings. The floss provides a scaffold for resin application and helps distribute stress. Secure the floss tightly—any slack allows movement during polymerization.
Apply Pattern Resin
Mix pattern resin to a slightly runny consistency and flow it over the floss connections, building up sufficient bulk for rigidity (minimum 3mm diameter). Work quickly before the resin becomes too viscous. Cover all floss completely to encapsulate the scaffold. Allow full polymerization per manufacturer instructions.
Section the Splint
This is the critical shrinkage-compensation step. Using a thin sectioning disc, cut completely through the resin splint between each pair of copings. Make cuts perpendicular to the splint axis. The sections will have shifted slightly due to polymerization shrinkage—you'll correct this in the next step.
Relute the Sections
Apply a thin mix of pattern resin to rejoin the sectioned areas. Use minimal material to reduce secondary shrinkage. Allow complete polymerization. This section-and-relute technique breaks the shrinkage vector, allowing each segment to shrink independently before reconnection.
Verify Rigidity
Apply lateral force to the completed splint. There should be zero perceptible movement or flex. Test each connection point individually. Any flex indicates insufficient bulk or incomplete polymerization—reinforce before proceeding to the impression.
Alternative: Metal Splinting
For guaranteed rigidity without shrinkage concerns, use a prefabricated dental implant verification jig system. Connect stainless steel links between impression copings using the manufacturer's locking mechanism. Metal splints eliminate polymerization variables entirely.
Tips & Best Practices
- Allow resin to polymerize completely before sectioning; premature cutting introduces additional distortion
- Make section cuts as thin as possible to minimize the gap requiring reluting
- Consider multiple section-relute cycles for maximum accuracy in critical cases
- Document your splinting technique for dental laboratory reference
Common Mistakes to Avoid
Skipping the section-relute step
Unsectioned resin splints contain 6-7% polymerization shrinkage that directly transfers to your dental master cast as positional error.
Insufficient splint bulk
Thin resin connections flex under impression removal forces, negating the purpose of splinting.
Contaminating cut surfaces
Oil, saliva, or debris on sectioned surfaces prevents proper reluting adhesion, creating weak points.