Prefabricated Boston Core — Clinical Procedure (Tooth #26)
This document summarizes the protocol for placement of a prefabricated Boston Core post in tooth #26. It covers instruments and materials, step-by-step technique for gutta-percha removal, post-space preparation, post selection and adjustment, cementation, and important cautions.
Indications
- Restorative retention when a post-and-core is required for an endodontically treated tooth (tooth #26 in this procedure).
- When a prefabricated para-post (Boston Core) is selected for core support.
Instruments and Materials
- Gates-Glidden drills (for gutta-percha removal)
- Para-post drills (corresponding to selected post system)
- Para-post pins (prefabricated posts)
- XP Para-post self-adhesive resin cement (or equivalent self-adhesive resin cement)
- Heavy wire cutter (to trim post)
- Ruler (to measure post length)
- Water spray, air syringe
- Paper points (to dry post space)
- Mixing pad
- Radiographs and/or magnification (lens/microscope)
Table: Instruments and Purpose
- Gates-Glidden drills — remove gutta-percha to radiographic working length
- Para-post drills — prepare post space to match chosen post
- Para-post pins — trial fit and final post
- Self-adhesive resin cement (XP Para-post) — cementation
- Heavy wire cutter & ruler — trim post to correct length
- Water, air, paper points — irrigate and dry post space
Pre-procedure Checks
- Confirm working length radiographically before and during gutta-percha removal.
- Plan post length so that post space does not exceed one-third of the root width.
- Verify direction and force during instrumentation to avoid lateral perforation.
Step-by-Step Procedure
1. Removal of Gutta-Percha
- Use Gates-Glidden drills to remove gutta-percha to the predetermined radiographic working length.
- Work with controlled direction and minimal pressure to avoid perforation.
- Monitor visually and radiographically (or with magnification) while working.
- Verify that the material being removed is gutta-percha (appears pink in this context) rather than dentin (white).
2. Preparation of the Post Space
- Select the para-post drill that corresponds to the chosen post.
- Use the para-post drill at low speed and with minimal pressure.
- Advance the drill only to the planned length; check length frequently (clinically and radiographically).
- Ensure the prepared post space does not exceed one-third of the root width.
3. Post Selection, Trial Fit and Adjustment
- Try-in the corresponding para-post pin to confirm fit and length.
- Adjust the post length as needed:
- Measure the desired length with a ruler.
- Trim excess material using the heavy wire cutter.
- After trimming, re-check the fit and adaptation in the prepared post space.
4. Cleaning and Drying the Post Space
- Rinse the post space with water to remove debris.
- Dry the post space thoroughly with air and paper points before cementation.
5. Cementation with Self-Adhesive Resin Cement
- RelyXunicem
- Prepare the self-adhesive resin cement on a mixing pad per manufacturer’s instructions.
- Apply cement to:
- All walls of the prepared post space
- The surface of the post itself
- Insert the post fully and maintain steady pressure to seat it.
- Remove excess cement immediately.
- Allow the cement to set completely before proceeding with core build-up or final restoration.
Post-cementation Checks
- Confirm post seating clinically and radiographically.
- Ensure no excess cement remains in the coronal area.
- Proceed with core build-up and final restoration once cement has fully set.
Clinical Tips and Warnings
- Always confirm working length and direction radiographically to prevent perforation.
- Use minimal pressure and low-speed instrumentation for post-space preparation.
- Avoid over-preparation — do not exceed one-third of the root width.
- Verify that removed material is gutta-percha (pink) and not dentin (white).
- Keep the post space clean and dry before cementation for optimal adhesion.
- Follow the cement manufacturer’s handling and setting recommendations.
Quick Reference Checklist
- Confirm radiographic working length
- Remove gutta-percha with Gates-Glidden (controlled pressure)
- Prepare post space with para-post drill (low speed, minimal pressure)
- Ensure post space ≤ 1/3 root width
- Trial-fit post; measure and trim to length
- Rinse and dry post space
- Apply self-adhesive resin cement to walls and post
- Seat post, remove excess cement, allow to set
- Final radiographic confirmation
This procedure provides a concise, controlled approach for placement of a prefabricated para-post (Boston Core) in tooth #26 using self-adhesive resin cement. Adjustments should be made according to clinician judgment and the specific manufacturer’s instructions for the post and cement systems used.