The screw retained versus cement retained implant crown decision comes down to one practical question: how easily can the crown be taken off again if it ever needs to be. Screw retained crowns unscrew. Cement retained crowns are glued onto an abutment and usually have to be cut off. Everything else is detail around that difference.
This is not a choice patients are asked to make, and it should not be. It is a clinical decision driven by the angle of the implant, the position of the tooth and how the crown will be maintained. It is still worth understanding, because it affects what happens years later when a screw loosens, a crown chips or the gum around the implant needs attention.
Key takeaways
- A screw retained crown is held on by a small screw through the biting surface, and the access hole is filled with composite afterwards.
- A cement retained crown is cemented onto an abutment, much like a conventional crown on a tooth.
- Reported five year survival is close for both, roughly 96.0 per cent for cement retained and 95.6 per cent for screw retained, with no statistically significant difference.
- Retrievability is the main advantage of screw retention, and implant angle is the main reason cement retention is chosen instead.
- Excess cement left below the gum is a recognised risk factor for peri-implant disease, and most of it does not show up on an x-ray.
- Neither option is universally better, and the risk associated with cement is managed by technique rather than avoided by refusing cement altogether.
What the two options actually are
An implant has three parts: the implant itself in the bone, an abutment that sits on top of it and passes through the gum, and the crown you see and chew on. How the crown joins the rest is where the two approaches differ. If the components are new to you, the parts of a dental implant explained covers them in more detail.
Screw retained
The crown and abutment are made as one unit, or joined in the laboratory, and a small screw passes up through the biting surface of the crown into the implant. The screw is tightened to a set torque, then the access channel above it is sealed and filled with tooth coloured composite. On a back tooth the filled hole is usually invisible in normal conversation, and you would only notice it if you went looking in a mirror.
Cement retained
An abutment is screwed into the implant first, then a separate crown is cemented onto that abutment. The biting surface is uninterrupted, so the shape and contact points can be built without designing around a screw hole. This is the approach that most resembles a conventional crown on a natural tooth.
Why the decision is made at the planning stage
The choice is usually locked in before the implant is even placed, because it depends on the angle at which the implant sits in the bone.
A screw has to come out through the crown along the long axis of the implant. On a molar that channel exits through the chewing surface, which is easy to hide. On an upper front tooth, the bone often slopes in such a way that the screw channel would exit through the visible front face of the crown, which is unacceptable both cosmetically and structurally. In that situation the options are cement retention, or an angled screw channel, which uses a specially designed screwdriver to redirect the access hole by up to about 25 degrees so it exits behind the tooth instead.
This is one of the reasons planning software and a surgical guide matter. Placing an implant where the bone is easiest, rather than where the crown needs to be, can remove the screw retained option before anyone has thought about it.
What the evidence shows
The honest summary is that both work, and the differences are in the pattern of problems rather than in outright failure rates.
Reported five year cumulative survival sits at around 96.0 per cent for cement retained restorations and 95.6 per cent for screw retained, a difference that is not statistically significant. In other words, if survival of the crown is the only measure you care about, the two are effectively equal.
Complications are where they separate. One analysis found screw retained restorations carried roughly a 46 per cent lower risk of complications overall. Screw retained restorations have also shown slightly lower rates of biological complications such as fistula formation and suppuration around the implant. Part of that is retrievability: a screw retained crown can be removed, cleaned, repaired and replaced without destroying it, so problems that would be a major undertaking on a cemented crown become a routine appointment.
On the inflammation question specifically, meta-analysis evidence suggests no significant difference in the risk of peri-implant mucositis between the two, with moderate certainty of equal risk for both mucositis and peri-implantitis. That is a more balanced picture than the internet usually gives.
The cement problem, kept in proportion
The concern with cement is not the cement itself but what happens to the excess. When a crown is seated, surplus cement is squeezed out at the margin. If that margin sits deep below the gum, some of the excess can be very difficult to see and remove.
A systematic review identified excess cement as a possible risk indicator for peri-implant disease. Two findings from that work are worth knowing. Excess cement was more often seen where the soft tissue healing period had been shorter than four weeks, and the majority of excess cement was not visible on radiographs. That second point matters, because it means an x-ray showing nothing is not proof that nothing is there.
The practical response is technique rather than avoidance. Where cement is used, a crown margin at or near the level of the mucosal margin with good access is recommended, so excess can be seen and cleaned away. Other approaches include using a replica abutment outside the mouth to extrude most of the cement before seating, and allowing adequate soft tissue healing before the crown goes on. Persistent inflammation around a cemented crown should always prompt a look for retained cement, which is one of the reversible causes discussed in peri-implantitis treatment.
Side by side
| Feature | Screw retained | Cement retained |
|---|---|---|
| How it attaches | A screw through the biting surface into the implant | Cemented onto an abutment that is screwed to the implant |
| Removal for repair or review | Unscrewed, usually without damaging the crown | Often has to be cut off and remade |
| Reported five year survival | About 95.6 per cent | About 96.0 per cent |
| Overall complication risk | Lower in at least one analysis, by roughly 46 per cent | Higher, largely driven by cement related issues |
| Peri-implant inflammation risk | No significant difference in the pooled evidence | No significant difference, provided excess cement is controlled |
| Main limitation | Implant angle must allow an acceptable screw exit | Excess cement below the gum can be hard to detect |
| What you may notice | A small tooth coloured filling on the biting surface | An uninterrupted biting surface |
| Typically favoured for | Back teeth, multi unit work, cases needing future access | Angled implants and some front teeth where the screw would exit visibly |
What this means for you as a patient
Day to day, very little. Both types of crown are cleaned the same way, with attention to the area where the crown meets the gum. Both need the same review schedule and the same interdental cleaning, as covered in implant aftercare and maintenance.
The difference shows up on the rare days when something needs attention. Implant screws can loosen, particularly on single crowns and in people who grind. With a screw retained crown, tightening it again is a short appointment. Porcelain can chip, and a screw retained crown can be sent back to the laboratory rather than remade from scratch. If the gum around the implant becomes inflamed, removing the crown gives direct access for cleaning.
With a cemented crown, all of those become harder. Not impossible, but harder, and sometimes at the cost of the crown itself. That is the trade being made in exchange for a better shaped, better positioned restoration in cases where the implant angle demands it.
The one question worth asking
You do not need to arrive with an opinion about retention. You just need to ask this: if this crown ever needs to come off, how will it come off?
A good answer is specific. It will explain which method is planned, why the implant angle allows or prevents screw retention, and what the removal process would look like. If the answer is cement retention, a follow up question is where the crown margin will sit relative to the gum and how excess cement will be managed. Those are fair questions and any implant clinician will have a ready answer.
Common questions
Is a screw retained implant crown better?
Not universally. Survival rates are close, and the pooled evidence shows no meaningful difference in peri-implant inflammation. Screw retention is preferred where the implant angle allows it because it is retrievable and shows fewer complications overall, but a well executed cemented crown on a correctly designed abutment is a sound restoration.
Will I be able to see the screw hole?
Usually not. The access channel is sealed and filled with tooth coloured composite that is polished flush with the biting surface. On back teeth it is essentially invisible in normal use. The filling material may need refreshing over the years, which is a short appointment.
Can a cemented implant crown be removed if there is a problem?
Sometimes, but often it has to be cut off and remade, which adds cost and time. Some clinicians deliberately use a weaker temporary style cement on implant crowns to keep removal possible, accepting a small risk of the crown loosening in exchange for retrievability.
Does excess cement always cause peri-implantitis?
No. Excess cement is a possible risk indicator, not an inevitable cause, and many cemented crowns function for years without incident. The risk rises when the margin sits deep below the gum, when the crown is fitted before the soft tissue has healed fully, and when the excess is not detected, since most of it does not appear on x-rays.
Can a crown be changed from cement retained to screw retained later?
In some cases yes, if the implant angle permits it, because a new screw retained crown can be made on the same implant. It means remaking the restoration rather than modifying it, so it is usually only done when the crown needs replacing anyway.
Does the crown material change the decision?
Not greatly, though it interacts with it. Zirconia and porcelain fused to metal both work with either method, and the material choice is driven more by the bite, the shade and the gum position. The differences are set out in implant crown materials compared.
Talk it through with the team at Lumi Dental
The team at Lumi Dental in Melrose Park offers a complimentary implant consultation, including the imaging and planning needed to decide how a crown should attach, and a written plan you can take away. If you already have an implant and are unsure how your crown is retained, that can be checked and recorded for you.
Learn more on our dental implants page, or get in touch to arrange a time. For background on how implant treatment is costed across the market, see our implant cost guide.
