Find out what a partial dental crown is, how is it different from a full crown, what are the different types of partial crowns and when they are recommended to use. Read this article to learn more about all of these!
Dental crowns are widely used after certain dental treatments like implant restorations or root canal treatments to help the remaining tooth structure by supporting and maintaining its integrity.
Also, they themselves might be the treatment option for aesthetics and functional purposes. Based on the coverage of the tooth portion, they can be classified as
Full Crowns vs Partial Crowns
Full crowns are classified depending on the material used for its preparation:
- All metal crown
- All ceramic crown (e.g.: zirconia, emax)
- Porcelain crown
- PFM crowns
Partial crowns are classified depending on the coverage of the tooth:
- Three quarter crown
- Reverse 3/4 th crown
- Seven eighth crown
- One half crown
- Conservative crowns
Full crowns cover all the surfaces of the tooth including the occlusal/ incisal surface (i.e., the upper surface which is the roof of the tooth along with 4 walls) whereas partial crowns covers only some surfaces of the tooth based on which they are classified.
Three-quarter crown: Covers approximately three-fourth area of the tooth, as the name suggest. It covers the roof and 3 walls of the tooth leaving the labial wall (outer wall) intact.
Reverse three-quarter crown: This crown is commonly used in lower rear teeth. It is the same as three fourth crown, covering 3 walls and the occlusal (roof) surface but it leaves the lingual/ palatal (inner) wall intact, that is why, it is called reverse three-fourth crown. To simplify it more, imagine sitting on the pouffe, facing towards the east is three-quarter crown and its reverse is turning behind by 180 degrees facing the west
Seven-eighth crown: This type of crown is the extension of three quarter crown covering the three walls and the roof along with the major portion of outer wall. This in all covers almost the entire area of the tooth.
One-half dental crown: This is also like three quarter crown but the distal wall of the tooth (the wall which is away from the midline contacting the rear tooth) is preserved . Now imagine the same scenario, sitting on the pouffe facing towards the north/south, which is 90 degree rotation of the three-quarter crown.
Conservative crown: This includes laminates which only covers the outer / labial (visible when you smile) surface of the tooth. Laminates are used in front teeth. It is exclusively used for aesthetic purposes to cover gaps or spaces between the teeth, to get lighter shade for heavily stained tooth etc.
What are onlays and inlays?
Onlay is a type of heavy restoration which replaces the missing cusp of the rear teeth which is used primarily for chewing function whereas inlay just fills the gap in between the cusps of the tooth.
What are partial crowns made up of?
Partial crowns are made up of metal, metal ceramic, porcelain etc, same materials as those in full crowns. The material chosen primarily depends on its purpose of placement. Only laminates are made up of porcelain and they are not available in metals as they are primarily placed for aesthetic purpose.
The most common type for front tooth is zirconia or emax. You can also get a same day Cerec crown if your dentist has the appropriate device to manufacture it in the office. Metal crowns (e.g. gold) or porcelain fused to metal ones are more common in the molar area.
The type of partial crown selection depends on the tooth on which it is to be placed, tooth angulation etc.
If you want to know more about what materials are preferred for dental crowns and why, read our article: A Comparison of Dental Crowns – Front and Back Teeth
When do you need a partial crown instead of a full crown?
Partial crowns are indicated only when your tooth structure is healthy, free of caries, firm and strong enough to provide sufficient surface area for a better grip and retention of the partial crown when glued.
If there is a possibility of periodontal problems or any gum disease or cavities, it is always better to get a full crown as it protects the remaining tooth structure.
The best advantage of partial crown is that relatively small amount of trimming of tooth is required as compared to full crowns.
Cost of partial crowns
The cost of partial crowns is nearly the same for almost all the types. It depends on the material used for fabrication, dentist’s charges and various other factors too.
Prices may vary slightly depending on systems like Emax, Cerec, In- ceram etc. Partial metal (stainless steel) and metal-ceramic partial (stainless steel with ceramic) crowns are comparatively less expensive than porcelain/ceramic partial crowns.