Dentistry is both a science and an art. A good dentist must have the skills and attention to details in order to deliver a quality restoration. This is never more true than when it comes to crowns and bridges. Here are some guidelines as to what makes a good crown vs a bad crown.
Qualities of a Good Crown:
- Perfect fit at the margins and to the adjacent teeth
- Proper emergence profile of the crown from the gum line
- Excellent contact between the neighboring teeth
- Excellent occlusion, i.e the fir of the crown to the opposing teeth
- Excellent color to match natural teeth
Qualities of a Bad Crown:
- Poor fit- this results in recurrent decay, sensitivity and ultimate failure of the crown
- Over contoured crown- this results in inflammation of the gum tissue, gum disease and movement of the crown by muscle forces
- No contact between the adjacent teeth-results in movement and tipping of the crown
- Poor color and not natural looking
Examples of Good Crowns
Examples of Bad Crowns
Now you know what a good crown should look like and how it should fit to the tooth. A good crown requires a high degree of skill and attention to details which creates the correct outcome.
Many of patients ask me why I dont take the final impression for a crown or bridge the same day as I prepare the tooth or teeth. They invariably say “My previous dentist did everything at the same appointment, why do I have to come back and get numbed again and spend another hour in the dental chair?”
Fair question and here’s my answer:
Its all about control of the process, provisionalization, accuracy and final fit of the restoration. We have already talked out provisionalization and why I feel thats important (Click here for blog on provisionalization) and why I spend more time on the provisional restoration so tooth position is maintained and the gum tissue around the prep heals and is healthy prior to taking the impression. Most dentists who take their impressions the same day as they prep are invariably fighting bleeding and sulcus fluid which compromises the accuracy of the impression. It has been estimated that 80-85% of all dental impressions sent to dental laboratories are inadequate for various reasons.
I would rather control the process by taking a little extra time and effort to assure that when I take my final impressions the field is dry and the tissue is healthy so when I pack my cord I get perfect tissue retraction and a subsequent 100% accurate impression and permanent crown back from the lab.
By: Brian Guldbek, D.D.S.
Part III of My Dental Journey
I had my comprehensive patient visit with Dr. David Newkirk in Naperville yesterday to discuss the restorative options for my fractured front tooth. He provided a very thorough exam as well as taking extensive intra and extra-oral photos so that we could sit down and discuss the case. His entire staff was very friendly, accomodating and made me feel comfortable.
Treatment planning was complicated because the periodontist felt an immediate implant was not indicated and that a bone graft was needed , so we needed to decide how we would temporize #9 during the 8 week healing period after the bone graft was placed. In the end, we decided that we would restore four of my front teeth with two crowns and two veneers to re-create harmony in my smile.
Next up, Dr. Newkirk will prepare #8 for a crown and fabricate a splinted lab processed provisional restoration for #8 and an ovate pontic for #9 to facilitate bone and tissue contours for the implant. I’m so glad I wont have to wear a flipper with a tooth for 8 weeks!!
Thanks Dr. Newkirk
By: Brian R Guldbek, D.D.S.