People often picture a dental implant as a single screw with a tooth on top. In fact a single-tooth implant is usually three separate pieces, fitted at different stages: a post in the bone, a connector called an abutment, and the crown you see. Knowing what each part does makes the treatment timeline easier to follow, and explains why one part can often be repaired or replaced without disturbing the others.
The post sits in the bone where the root used to be
The implant itself, sometimes called the fixture, is a small threaded post placed in the jawbone. Most are made of titanium or a titanium alloy, and some are made of zirconia, a tooth-coloured ceramic. Titanium is used because it is strong, light and well accepted by the body.
After placement, bone gradually grows onto the surface of the post and locks it in place, a process called osseointegration. For many implants this takes around three to six months before the post is ready to carry a crown, although timing varies with the bone and the treatment plan. Our article on osseointegration explains that healing stage in detail. Once integrated, the post is designed to stay for the long term and is not normally visible.
The abutment connects the post to the crown
The abutment is the middle piece. It attaches to the top of the post, usually with a small screw, and passes through the gum so the crown has something to sit on. It also shapes the gum around the new tooth, which matters for appearance at the front of the mouth.
Abutments come in two broad types. Stock abutments are ready-made shapes. Custom abutments are designed for the individual implant, which helps when the post is at an angle or the gum line needs careful shaping. Titanium is common, and zirconia may be chosen where the gum is thin and grey metal might show through. The abutment is often fitted once the post has healed, but in some treatment plans it goes in on the day of surgery.
The crown is the part you see and chew with
The crown is made to match the size, shape and colour of your other teeth, often from a digital scan of the mouth. Common materials include zirconia, other ceramics and porcelain fused to metal. A crown can be held on in one of two ways:
- Screw-retained. The crown is fixed to the abutment, or to the implant directly, by a screw reached through a small access hole that is then sealed with tooth-coloured filling material. The crown can be removed later for maintenance.
- Cement-retained. The crown is cemented onto the abutment, like a crown on a natural tooth. Any excess cement must be removed carefully, because cement left under the gum can irritate the tissues. In one study of implants with signs of gum and bone inflammation, excess cement was found in 81% of the affected cases, and inflammation had settled in most of them a month after it was cleaned away (Wilson, Journal of Periodontology, 2009).
How the three parts compare
| Part | Usual materials | Job | Visible in the mouth? |
|---|---|---|---|
| Implant post (fixture) | Titanium, titanium alloy or zirconia | Replaces the root and anchors in bone | No |
| Abutment | Titanium or zirconia | Links the post to the crown and shapes the gum | Mostly hidden at or below the gum |
| Crown | Zirconia, other ceramics or porcelain fused to metal | Restores the look and chewing surface of the tooth | Yes |
Separate parts make maintenance easier
Building an implant from components means the post can heal quietly before it is loaded, the abutment can be changed if the gum shape needs adjusting, and a worn or chipped crown can often be remade without touching the post in the bone. The stages are set out in our guide to how dental implants work, step by step.
What tends to go wrong, and where
Long-term studies show implants themselves usually last well, but smaller problems are common enough to plan for. A systematic review of single implant crowns followed for an average of five years (Jung and colleagues, Clinical Oral Implants Research, 2012) estimated implant survival at about 97% after five years. Over the same period, screws came loose in about 9% of crowns, crowns lost retention in about 4%, and the porcelain chipped in about 3.5%. Problems in the gum around the implant affected about 7%.
In practical terms:
- The post depends on healthy gum and bone. Gum disease around an implant and smoking are the main threats. Our guide to peri-implantitis covers this.
- The abutment screw can loosen, which may feel like a slight wobble in the crown. It is usually straightforward to fix if it is checked early.
- The crown takes the daily wear of chewing and can chip, much like a natural tooth.
Daily cleaning around the implant and regular reviews protect all three parts. If you are still comparing options, our articles on an implant versus a bridge or denture and how long dental implants last may help.
Common questions
Is the screw the whole implant?
No. The screw-shaped post is only the foundation. A complete single-tooth implant also has an abutment and a crown, usually fitted after the post has healed.
Will any metal show?
Not normally. The post sits in bone and the abutment is mostly under the gum. Where the gum is thin, a zirconia abutment can reduce the chance of a grey tint.
Can one part be replaced on its own?
Often, yes. A crown can usually be remade and an abutment changed while the post stays in place.
How long does it take to fit all three parts?
The post is placed first. After healing, usually around three to six months for many implants, the abutment and crown are fitted. Timelines vary, particularly if bone grafting is needed. Our article on getting an implant years after an extraction covers one common situation.
Thinking about an implant?
If you are missing a tooth and would like to know whether an implant suits you, dental implants are placed at Lumi Dental, and you can start with a free implant consult. Learn more on our dental implants page or see the current options on our offers page.
This article is general information only and is not a substitute for personal dental advice. Please see a dentist to discuss your own situation.
