Risks & complications

The honest list. What can go wrong with an All-on-5.

Every surgical reconstruction carries risks. The dishonest version of this page would omit them. The useful version lists what they are, how often they happen, what reduces them, and what to do if they do.

Clinically reviewed · Last reviewed 24 May 2026 · Editorial & review

Surgical risks

During placement. Uncommon, named, mitigated by planning.

S1 / Implant misalignment Mitigated by guided surgery.

An implant placed at a poor angle can compromise the prosthesis or the screw access path. The CBCT-derived surgical guide is the standard defence.

S2 / Nerve disturbance Rare in upper arch, low in planned lowers.

Lower-arch implants close to the inferior alveolar nerve can cause temporary or, very rarely, persistent numbness. CBCT margins are non-negotiable.

S3 / Sinus involvement Upper-arch specific.

Posterior upper implants near the maxillary sinus may require sinus elevation. Performed routinely when planned; problematic when discovered intra-operatively.

S4 / Excessive bleeding Medication history dependent.

Patients on anticoagulants or with bleeding disorders require pre-surgical co-ordination. Stops being a surprise when it is reviewed in advance.

Healing window risks

The first 12 weeks. Where most preventable failures occur.

H1 / Early implant failure ~2–5% across the literature.

Failure to integrate during the first months. Caught at scheduled reviews. The implant is removed, the site is allowed to heal, and a replacement is placed when conditions allow.

H2 / Provisional fracture Diet discipline matters.

The provisional bridge is acrylic and built to be soft-loaded. Hard foods, ice, and nut shells in this window have written consequences.

H3 / Soft-tissue infection Caught at the 48-hour and two-week reviews.

Localised inflammation around an implant. Treated quickly with rinses, antibiotics if indicated, and adjusted hygiene technique. Rarely jeopardises the case if caught early.

H4 / Bruxism damage Night appliance recommended.

Heavy clenching during sleep concentrates load on the provisional bridge. A soft night guard is a small investment with a large protective effect.

Long-term risks

Years after. Scheduled service is the protection.

L1 / Peri-implantitis The single most important long-term risk.

Inflammation and bone loss around an implant. Almost entirely a consequence of poor hygiene over years. Reversible early, structural late.

L2 / Screw loosening A service event, not a failure.

Screws under repeated bite forces can loosen. Detected at routine review by the clinician. Re-torqued in minutes.

L3 / Tooth-layer fracture Material-specific.

Porcelain chips, zirconia fractures at screw channels, PMMA wears. Each has a planned response — repair, refresh, or replacement on the original implants.

L4 / Late implant failure ~5% over 10 years in the literature.

Less common than early failure. Often associated with smoking, uncontrolled diabetes, or missed maintenance. Replacement is possible on the same plan with a healing window.

What reduces every risk on this page

Five protective factors, in order of impact.

01

Not smoking. The single largest modifiable factor. Smokers carry materially higher implant-failure rates and slower healing. Most warranties specifically exclude continued smoking.

02

Honouring the recall schedule. Six-monthly hygiene + yearly clinician review. Most long-term complications are caught here before they become problems.

03

Controlled systemic conditions. Well-managed diabetes, treated periodontal disease, and stable medication regimens before surgery.

04

Bruxism management. Night guard if indicated. Untreated bruxism is the most common cause of avoidable component failure.

05

Daily hygiene with the right tools. Water flosser, angled brush, sized interdental brushes. The cost of these tools is trivial compared to a remade bridge.

This page describes typical risks discussed in patient-education contexts. It is not a substitute for the written informed-consent discussion with your clinician, who knows your specific records and history.
Aftercare

The maintenance schedule that prevents most of the long-term list above

 Candidacy

Who All-on-5 is for — and which risk profiles need a different plan

 Glossary

The medical terms used on this page, in plain English

Sources & further reading

Reviewed 24 May 2026
  1. American Academy of Implant Dentistry (AAID). Full-arch implant reconstruction — patient resources. aaid.com
  2. American Dental Association (ADA). Dental implants — MouthHealthy patient guide. mouthhealthy.org
  3. International Team for Implantology (ITI). Consensus on full-arch fixed prostheses and immediate loading protocols. iti.org
  4. Glossary of Prosthodontic Terms. Definitions of cantilever, multi-unit abutment, screw-retained prosthesis, osseointegration. The Journal of Prosthetic Dentistry.
  5. European Association for Osseointegration (EAO). Position papers on peri-implant maintenance and long-term success criteria. eao.org
  6. National Library of Medicine (PubMed). Searchable index of peer-reviewed implant-dentistry literature. pubmed.ncbi.nlm.nih.gov