Removing Resin from Inside a Crown 

April 19, 2024 Lee Ann Brady DMD

By Lee Ann Brady, DMD 

When a crown comes off and we are going to put it back in the mouth, we need to remove the old resin cement that is inside the crown. What is the best way to go about this? 

First, we need to know if the crown is made of zirconia or lithium disilicate. If you have a radiograph of that restoration, you can tell immediately which one of those two things it is. If you don’t, you can always attempt to X-ray it. (That’s what I do.) Alternatively, you can assume the crown is made of lithium disilicate, which is the more technique-sensitive material when it comes to removing cement. 

For crowns confirmed to be zirconia, employing 30-micron aluminum oxide air abrasion effectively clears out the old resin cement. Subsequently, re-etching the inside of the zirconia prepares it for reseating. For crowns presumed to be lithium disilicate, this approach should be avoided to prevent crack propagation. 

In the case of lithium disilicate crowns, two alternative methods can be employed: 

  1. The crown can be placed in a porcelain oven to liquefy and evaporate the old resin. However, caution must be exercised to avoid rapid heating of the hydrated ceramic that has been in the oral environment. Rapid dehydration will introduce cracks and lead to crown fracturing. 
  1. An alternative method involves using a brown silicone point in a high-speed handpiece, adjusted to lowest speed. A brown silicone point at slow speed effectively removes resin without damaging ceramic. 

How will you know when all the resin has been removed? When etching lithium disilicate, whether using red 5% hydrofluoric acid or Monobond Etch & Prime from Ivoclar Vivadent, any remaining resin will be evident because the dye sticks to it after the etching solution is rinsed off.  

Related Course

Worn Dentition: Direct & Indirect Adhesive Management Through a Non-Invasive Approach

DATE: October 24 2025 @ 8:00 am - October 25 2025 @ 2:30 pm

Location: The Pankey Institute

CE HOURS: 15

Dentist Tuition : $ 2595

Single Occupancy with Ensuite Private Bath (per night): $ 345

Enhance Restorative Outcomes The main goal of this course is to provide, indications and protocols to diagnose and treat severe worn dentition through a new no prep approach increasing the…

Learn More>

About Author

User Image
Lee Ann Brady DMD

Dr. Lee Ann Brady is passionate about dentistry, her family and making a difference. She is a general dentist and owns a practice in Glendale, AZ limited to restorative dentistry. Lee’s passion for dental education began as a CE junkie herself, pursuing lots of advanced continuing education focused on Restorative and Occlusion. In 2005, she became a full time resident faculty member for The Pankey Institute, and was promoted to Clinical Director in 2006. Lee joined Spear Education as Executive VP of Education in the fall of 2008 to teach and coordinate the educational curriculum. In June of 2011, she left Spear Education, founded leeannbrady.com and joined the dental practice she now owns as an associate. Today, she teaches at dental meetings and study clubs both nationally and internationally, continues to write for dental journals and her website, sits on the editorial board of the Journal of Cosmetic Dentistry, Inside Dentistry and DentalTown Magazines and is the Director of Education for The Pankey Institute.

FIND A PANKEY DENTIST OR TECHNICIAN

I AM A
I AM INTERESTED IN

VIEW COURSE CALENDAR

Acetone to the Rescue!

August 9, 2023 Lee Ann Brady DMD

Seating dental restorations with resin-based cement can be daunting. The process is extremely technique sensitive and requires multiple steps. One of the things I learned years ago is to keep a small cup of acetone or ethanol on the tray table when I am seating restorations using resin-based cement.

All our resin materials have a solvent in them. That solvent is often ethanol or acetone. The solvent disrupts the chemistry, spreads out particles, and stops the resin from polymerizing. So, we can use a solvent to prevent the resin from setting and turn it completely into a liquid then wipe it away. Now we can go back to our steps to clean the ceramic, selenate the ceramic, etch the tooth, apply the dental adhesive, and freshly seat the restoration in the same appointment.

Recently, I was in the process of seating veneers. I prepped #6 and loaded the resin. As I raised the veneer, I realized it was for #11 instead of #6. So, I dropped the veneer in the little cup of acetone on my tray. I soaked a 2×2 in the solvent and completely wiped the resin off tooth #6 and completely wiped the resin off the back of veneer #11. Then, I took a deep breath and was ready for a do-over.

This was the first time I had to use that little cup of solvent in over 15 years, but I was delighted it was on my tray table. Time and again we have thrown that little cup away—for years and years, and now I have experienced firsthand why that cup of solvent is always “at the ready” when I seat restorations using resin-based cement.


Here at Pankey, we are committed to helping you through any of the questions you might have while practicing dentistry. I recommend starting your advanced dental education journey with our Essentials 1 course. You will gain essential knowledge and skills, enabling you to build a solid understanding of fundamental concepts in dentistry. From fundamental principles to essential clinical techniques, The Essentials Series will lay down the groundwork for a successful dental practice and further specialization. 

Related Course

Functional Esthetic Excellence – Utilizing 100% Digital Workflow

DATE: May 8 2025 @ 8:00 am - May 10 2025 @ 2:00 pm

Location: The Pankey Institute

CE HOURS: 25

Dentist Tuition: $ 3195

Single Occupancy with Ensuite Private Bath (per night): $ 345

Embracing Digital Dentistry This course will introduce each participant to the possibilities of complex case planning utilizing 100% digital workflows. Special emphasis will be placed on understanding how software can…

Learn More>

About Author

User Image
Lee Ann Brady DMD

Dr. Lee Ann Brady is passionate about dentistry, her family and making a difference. She is a general dentist and owns a practice in Glendale, AZ limited to restorative dentistry. Lee’s passion for dental education began as a CE junkie herself, pursuing lots of advanced continuing education focused on Restorative and Occlusion. In 2005, she became a full time resident faculty member for The Pankey Institute, and was promoted to Clinical Director in 2006. Lee joined Spear Education as Executive VP of Education in the fall of 2008 to teach and coordinate the educational curriculum. In June of 2011, she left Spear Education, founded leeannbrady.com and joined the dental practice she now owns as an associate. Today, she teaches at dental meetings and study clubs both nationally and internationally, continues to write for dental journals and her website, sits on the editorial board of the Journal of Cosmetic Dentistry, Inside Dentistry and DentalTown Magazines and is the Director of Education for The Pankey Institute.

FIND A PANKEY DENTIST OR TECHNICIAN

I AM A
I AM INTERESTED IN

VIEW COURSE CALENDAR