All-on-4 immediate full arch: fixed teeth on implants

When all or nearly all the teeth in an arch are missing, you don't need one implant per tooth: a complete fixed arch, the hybrid prosthesis or All-on-4, is screwed onto four or six implants. Before surgery I measure the bone on a CT scan and design the prosthesis; during surgery I measure how firmly each implant sits. If they're stable, you leave with fixed provisional teeth; if not, we wait for the bone to integrate them.

Imaging

3D CT scan (CBCT)

Implants per arch

4 or 6, depending on bone

Fixed provisional

Only if the implants are stable

Final prosthesis

Once the bone integrates the implants

When it's indicated

• You've lost all or nearly all of the teeth in one or both arches.
• Your denture moves, hurts or keeps you from eating.
• Your remaining teeth have a poor prognosis and you want fixed teeth.
• You've been told there's no bone in the back: tilting the back implants can avoid a graft.

Before surgery

• If you already have a recent CT scan or panoramic X-ray, bring it to the consultation.
• Tell me about your health conditions, your medications (especially for your bones) and any radiation to the head or neck: they change the plan.
• If you have diabetes or might have it, we order an HbA1c test to catch poor control and adjust it before surgery.
• If you smoke, quit: in smokers, the risk of having an early implant failure was double that of non-smokers, counted per patient.
• If you're having sedation, come with someone and don't drive that day.

How I plan it

How I do it

1. 01ConsultationAt Hospital CIMA I examine your mouth, your imaging and your health, and explain whether All-on-4 suits you or what other option there is.
2. 02Plan and quoteI define how many implants and where, the provisional, the timeline and the cost of each phase. There are two parts, surgery and prosthesis: I tell you who does each one.
3. 03SurgeryUnder local anesthesia and, depending on the case, sedation. I remove the teeth that can't be saved and place the implants in the planned positions.
4. 04ProvisionalIf there's stability, a fixed provisional is screwed in; in one review, 1,201 fixed prostheses were placed within 48 hours after surgery. If not, you wear a removable one while the bone integrates the implants.
5. 05Final prosthesisAfter a few months of integration and check-ups, new records are taken and the final, stronger prosthesis is placed.

Recovery

• First 72 hours: this may be when pain control matters most; in trials, anti-inflammatory drugs reduced pain compared with placebo. For swelling, cold packs.
• Soft foods throughout the provisional phase: the provisional is the piece that breaks most; in an upper-jaw series, mechanical complications were 58.8% with the provisional and 7.3% with the final prosthesis.
• Gentle hygiene from day one and, later, a water flosser and interdental brushes under the prosthesis. No smoking.
• The first year is key: in one review, 74% of implant failures happened within the first 12 months. Don't miss those check-ups.
• For life, professional check-ups and cleanings: people who attend regularly have a lower risk of disease around their implants.

Risks and how I prevent them

Losing an implant

An overview of reviews reports cumulative survival of 94.8% to 99.3%, depending on the included review; in a systematic review, at 5 years or more, 98.14% of implants were still in place with four and 97.50% with six. Smoking was associated with more implant loss. Prevention: CT scan, measured stability and check-ups in the first year. If one fails, depending on the case a new one is placed and the prosthesis is adapted.

Fractures or loose screws

Mechanical complications range from 5.91% (systematic review) to 36.7% (series of up to 18 years), mostly with the provisional. In another review, the main one was fracture of the all-acrylic prosthesis; zirconia may reduce them. Prevention: soft foods, the right material and a night guard if you clench. They're repaired or adjusted.

Inflammation or bone loss around the implants

Biological complications were 6.54% in the systematic review and affected 11.8% of implants in the lower-jaw series. Prevention: daily cleaning under the prosthesis, maintenance, controlled diabetes and not smoking. If they appear, professional cleaning and peri-implantitis treatment.

Not being able to load right away

That isn't a failure: in well-selected cases, immediate, early and conventional loading had similar survival; implant survival was estimated above 99% at one year. Meanwhile, you wear a removable prosthesis.

Nerve or sinus injury

I locate both on the CT scan before planning. If numbness of the lip or chin lasts after the anesthesia has worn off, or you have sinus symptoms, let me know right away.

Other options

Keeping a full denture

Not having surgery is valid if there are medical risks or you don't want surgery. I also adjust upper and lower full dentures.

Implant overdenture

It's removable and clips onto implants. In the upper jaw, an overview of systematic reviews advises against resting it on fewer than four implants.

Keeping the teeth that can be saved

They're treated and only the missing teeth are replaced, with single implants, bridges or a partial denture.

Bone grafts or zygomatic implants

When there isn't bone even for four implants. Zygomatic implants, anchored in the cheekbone, are often indicated as an alternative to major graft reconstructions.

Frequently asked questions