Guide · Implant prosthetics
Open contact next to an implant crown: causes and fixes
Why the proximal contact between an implant crown and the adjacent tooth opens over time, how often it happens, how to diagnose it and how to close it.
Short answer
An open contact next to an implant crown is a common complication, mostly on the mesial: in a 2023 meta-analysis, 41% of contacts were open, and 47% of mesial ones. The usual explanation is that the implant doesn't follow the drift of the natural teeth around it. Floss-test the contacts at every recall and close them when the patient complains.
Step by step
- 01
Test the contact with floss
Run thin floss through both contacts of the crown and grade each one: tight, light or open. In Varthis and colleagues' study, a contact counted as open when 0.07 mm floss passed with no resistance.
- 02
Ask about food impaction and check the tissue
Ask whether food packs there and check the papilla, bleeding and probing depths on both sides of the contact. Symptoms and tissue, more than the gap itself, decide when to act.
- 03
Chart the surface, date and grade
Note which surface opened, when, and how it graded at the last recall, with an occlusal photo. A contact that was light from delivery and one that opened over the years are different problems.
- 04
Decide between monitoring and closing
With no food impaction or inflammation, monitoring at recalls is an approach described in the literature. With symptoms, the contact can be closed on the crown, on the adjacent tooth or orthodontically, and that call is yours.
- 05
If you're closing it on the crown, talk to the lab first
A screw-retained crown comes out and goes to the lab to have material added to the proximal surface, or to be remade. Agree on what to send and on the turnaround before you remove it, because the patient goes without the crown meanwhile.
- 06
Keep checking after you close it
Floss-test the contact again at the following recalls, because it can reopen. For a patient who bruxes, discuss an occlusal splint; some authors also suggest a removable retainer.
Why does the contact open next to an implant crown?
The contact opens because natural teeth keep moving while the implant, fused to bone like an ankylosed tooth, stays put. That’s the explanation Greenstein and colleagues give (The Journal of the American Dental Association, 2016): chewing forces move the teeth, usually mesially, and the implant crown doesn’t follow.
The cause isn’t proven yet. In Stilwell’s review (British Dental Journal, 2024), the main hypotheses are mesial drift of the teeth and facial growth that continues into adulthood, with no direct link shown to occlusal load. Liu and colleagues (Journal of Dental Sciences, 2026) add implant position and crown contour.
What’s well established is when and where. Contacts open more on the mesial, more often the longer the crown is in service, and they can open early: across the five studies Greenstein reviewed, gaps appeared from three months after delivery.
How often does the contact open?
The contact opens next to a large share of implant crowns that sit beside natural teeth, and the share grows with time in service. Reviews disagree on the number because studies measure at different times and with different criteria, but all of them point to the mesial.
| study | design | result | most often |
|---|---|---|---|
| Bento et al., J Prosthet Dent, 2023 | meta-analysis, 10 studies | 41% of contacts open | mesial (47%) and mandible (41%) |
| Sheba et al., J Prosthodont, 2024 | meta-analysis, 15 posterior studies | 44.2% mesial, 27.5% distal | no difference by age, sex or arch |
| Papageorgiou et al., Clin Oral Implants Res, 2018 | meta-analysis, 27 studies, up to 18.5 years | 46.3% contact loss | mesial; rises over time; very low quality evidence |
| Abduo and Lau, Heliyon, 2022 | qualitative review, 19 studies | 11–30% under 2 years; 29–83.3% after 5 | time in service and mesial surface |
| Varthis et al., Int J Oral Maxillofac Implants, 2016 | cross-sectional, 174 single crowns | 52.8% with an open contact | 78.2% of open contacts on the mesial |
In the same Papageorgiou review, the implant crown sat below the plane of the adjacent teeth (infraposition) in 50.5% of cases, by 0.58 mm on average. It’s the same phenomenon in the vertical direction.
What causes it, and what do you do about each cause?
The causes of an open contact add up, and the clinical sign helps separate tooth drift from the other sources. The table starts from what you find.
| cause | sign | what to do | source |
|---|---|---|---|
| Natural teeth drifting while the implant stays put | mesial contact that opens months or years later; floss passes with no resistance | monitor without symptoms; close with food impaction or complaints | Greenstein et al., 2016; Bento et al., 2023 |
| Time in service | contact that gets lighter from one recall to the next | floss-test at every recall and chart it | Abduo and Lau, 2022; Ko et al., 2024 |
| Ongoing growth and eruption | vertical step between the crown and the adjacent tooth | monitor; where esthetics matter, discuss a new crown | Papageorgiou et al., 2018; Stilwell, 2024 |
| Bruxism | wear facets, chipping | occlusal splint and a reviewed occlusal scheme | Liu et al., 2026 |
A light contact is the stage at which a recall still catches the problem before the complaint. Ko and colleagues (Journal of Dental Sciences, 2024) followed 40 posterior crowns: at 12 months, 22.5% had a light mesial contact and 12.5% an open one. At 24 months, 12.9% were light and 25.6% open, which suggests some of the light ones opened.
When should you treat an open contact?
Treat an open contact when it causes food impaction, complaints or inflammation; without those, monitoring is an accepted approach. Greenstein and colleagues (2016) recommend watching for signs and symptoms and repairing the gap when they show up. In Abduo and Lau’s review (Heliyon, 2022), the reported consequences were food impaction and patient dissatisfaction.
Tissue damage is less clear. In Ko’s study (2024), plaque, gingival inflammation, probing depth and bone loss didn’t differ between tight, light and open contacts over two years. Abduo and Lau also found the link to bone loss and bleeding unclear.
Patients notice, even when the tissue is fine. In Varthis’s study (2016), 40% of patients with an open contact were aware of the gap and of food packing.
Close it on the crown or on the adjacent tooth?
An open contact can be closed three ways, and the choice depends on the size of the gap, the state of the adjacent tooth and how the crown is retained. Liu and colleagues (Journal of Dental Sciences, 2026) describe the options:
- Composite on the adjacent tooth, for small gaps. It’s the most conservative route and leaves the crown alone.
- A remade crown, or one repaired with material added to the proximal surface, as Greenstein and colleagues (2016) also describe, when the crown is screw-retained and can come out.
- Orthodontic movement, when the adjacent tooth has drifted a long way.
The same authors note the limits of preventive approaches. An over-contoured contact gets in the way of hygiene and raises caries risk, and splinting the crown to its neighbors makes access harder. Stilwell (2024) points out that a closed contact can open again.
A screw-retained crown makes any crown-side fix easier, because it comes out without being cut. The trade-offs between the two retention types are in screw- vs cement-retained implant crowns.
Does a well-adjusted contact at delivery prevent it?
It doesn’t. Abduo and Lau (2022) describe contact loss as frequent, inevitable and progressive, and it’s measured precisely in contacts that were there at delivery. Adjusting the contact well still matters, because a light contact starts out close to open; it just won’t stop the loss over the years.
What the Rx controls is the capture of the adjacent teeth and the initial contact. That’s covered in why implant crowns get remade. This guide is about what happens later, with the crown in service.
What should you tell the lab?
Tell the lab which surface opened, when, how the contact was at delivery and what the floss showed, with photos and a radiograph. If the fix is on the crown, send a new scan of the arch too: the new contact is designed against where the adjacent tooth is now, not where it was in the old file.
Send the lab:
- The screw-retained crown with its Ti-base and screw, if it’s getting material added or serving as a reference.
- A current scan of the arch with the adjacent tooth, the opposing arch and the bite.
- If the crown is being remade, the scan with a scan body and the implant brand and platform.
- Photos and how the contact graded at earlier recalls.
- Whether the patient bruxes and whether you plan a splint or a retainer.
We check every case when it arrives and on eight points before it ships. Ask how adjustments and remakes work before your first case. The crown is on the zirconia implant crown page, and the night-time appliance on the milled occlusal splint page.
Related services
Open a portal accountFrequently asked questions
Should I warn the patient that the contact may open?
The review authors recommend it. Greenstein and colleagues (2016) and Abduo and Lau (2022) suggest telling patients the contact may open and food may pack, and checking the contact at every recall. Varthis and colleagues (2016) argue for including the risk in informed consent.
Does an open contact next to an implant cause bone loss?
No clear link has been shown. In a prospective study by Ko and colleagues (2024) of 40 posterior crowns over two years, plaque, gingival inflammation, probing depth and bone loss didn't differ between tight, light and open contacts. In Abduo and Lau's review (2022), the reported consequences were food impaction and dissatisfaction.
Does a retainer or night guard prevent the contact from opening?
No trial has shown it. Varthis and colleagues (2016) suggest an Essix-type removable retainer, and Liu and colleagues (2026) mention a night guard for patients who brux. These are author proposals without a comparative study behind them.
Sources
- Prevalence of proximal contact loss between implant-supported prostheses and adjacent natural teeth: a systematic review and meta-analysis · The Journal of Prosthetic Dentistry (Bento et al., 2023)
- Interproximal contact loss between implant restorations and adjacent natural teeth: a systematic review and meta-analysis · Journal of Prosthodontics (Sheba et al., 2024)
- Frequency of infraposition and missing contact points in implant-supported restorations within natural dentitions over time: a systematic review with meta-analysis · Clinical Oral Implants Research (Papageorgiou et al., 2018)
- Proximal contact loss between implant prostheses and adjacent natural teeth: a qualitative systematic review of prevalence, influencing factors and implications · Heliyon (Abduo and Lau, 2022)
- Prevalence of interproximal open contacts between single-implant restorations and adjacent teeth · The International Journal of Oral & Maxillofacial Implants (Varthis et al., 2016)
- Open contacts adjacent to dental implant restorations: etiology, incidence, consequences, and correction · The Journal of the American Dental Association (Greenstein et al., 2016)
- A two-year prospective study to compare the peri-implant parameters of posterior implant-supported single crowns with and without mesial proximal contact loss · Journal of Dental Sciences (Ko et al., 2024)
- Open contacts adjacent to posterior dental implants: current understanding and emerging preventive concepts · Journal of Dental Sciences (Liu et al., 2026)
- Occlusal considerations in maintaining health of implants and their restorations · British Dental Journal (Stilwell, 2024)
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