Immediate Full-Mouth Implant Rehabilitation with the All-on-Six Concept and a Digitally Fabricated Prosthesis in a Long-Term Smoker

1. Introduction

Full-arch rehabilitation on implants has changed how we treat patients with failing dentition. The All-on-Four concept, described originally for the edentulous mandible, placed four implants, with the posterior ones tilted, to support a fixed prosthesis that could be delivered immediately.³ Many clinicians now add implants to the basic concept. Using six implants provides more support points and more flexibility in how load is distributed, although direct comparative evidence between four and six implants remains limited.

Smoking complicates this treatment. A recent systematic review of 292 publications reported that implants placed in smokers had around 2.4 times the odds of failure compared with non-smokers.⁴ An earlier meta-analysis also linked smoking to poorer implant prognosis and more biological complications.⁵ For a patient who smokes, the surgical and prosthetic plan therefore has to be chosen deliberately, and the patient has to understand the risk.

This report describes a patient with a long smoking history who was treated with immediate extraction, immediate placement of six implants, an immediate provisional prosthesis and a digitally fabricated final prosthesis.

2. Patient information

A 64-year-old male patient presented to Dental Arch, Gurgaon, with difficulty chewing food and cheek biting. He had no systemic disease and was not taking any regular medication. He was a chronic smoker and had smoked for about 30 years.

3. Clinical findings and diagnostic assessment

• Broken-down teeth in both jaws, with difficulty chewing and cheek biting
• Panoramic radiograph (OPG) and CBCT showing multiple retained root stumps with periapical infection
• Implant planning carried out on the CBCT itself, to assess available bone and position the implants
• A digital intra-oral scan and clinical photographs to record the starting point and plan the prosthesis
• Risk assessment: long-term smoking, discussed with the patient as the main modifiable risk to implant success

Diagnosis: broken-down dentition with retained root stumps and periapical infection in both jaws, requiring extraction and implant-supported rehabilitation of both arches, in a patient with a smoking-related risk factor.

5. Treatment

5.1 Digital planning

We used a digital intra-oral scanner in place of conventional impressions to record the dentition and soft tissues, together with a panoramic radiograph, clinical photographs and CBCT. Implant positions were planned on the CBCT itself. This gave Dr. Goyal and Dr. Sharma the same digital record to plan implant positions and the prosthetic design from the start. Digital impressions have been shown to be time-efficient compared with conventional techniques for implant work, although the accuracy of full-arch scans is still an active research area.⁷

5.2 Surgery: immediate extraction and six implants

Under [local anaesthesia / sedation: confirm], the broken teeth and root stumps were extracted. Six implants per jaw, twelve in total, were placed immediately using the All-on-Six concept. We used the Osstem implant system ([diameters and lengths]), with insertion torque ranging from 15 to 35 Ncm. Multi-unit abutments were connected, and immediate provisional dentures were delivered on the day of surgery.

5.3 Healing and risk management

The patient wore the provisional prostheses for six months, with review visits every three months. He received oral hygiene instruction and counselling to stop smoking, or to cut down as far as possible, since continued smoking is the main modifiable factor affecting implant outcomes.⁴

5.4 Final prosthesis: a complete digital workflow

After six months, we recorded the implant positions digitally and designed the final prosthesis on computer. A 3D-printed model with implant analogues was produced for verification (Figure 2). The final denture was a monolithic Ivotion denture (Ivoclar), designed in CAD software and milled from a single bicolour disc that combines the tooth and base materials, so the teeth are not bonded to the base afterwards.⁸ The prosthesis is screw-retained, and the screw-access channels for all six implants are visible in Figure 4.

Both jaws were treated in the same way, with six implants in the maxilla and six in the mandible. Figures 2 to 4 show the mandibular prosthesis. Figure 5 shows both arches in occlusion, and Figure 6 compares the radiographs before and after treatment.

6. Follow-up and outcomes

The final prostheses were delivered and the occlusion adjusted, restoring chewing function and appearance in both jaws. [Add: follow-up duration, implant stability, soft-tissue health, any complications] The patient remains on a maintenance schedule with professional review every three months.

7. Discussion

Treating a smoker

Smoking was the main concern in this case. Smokers have a higher risk of implant failure and biological complications.^4,5 We did not treat this as a reason to refuse treatment. We treated it as a risk to be discussed openly, managed through careful surgical technique, a staged loading plan, a long healing period with close review, and strong advice to stop or cut down.

Why six implants

The original All-on-Four concept reported good results with immediate function in the edentulous mandible.³ Adding two implants gives additional support, and can offer more options if one implant fails to integrate. For a patient with a recognised risk factor, this extra margin was a reasonable choice. We note that comparative evidence for four versus six implants is limited, and the decision was made on clinical grounds for this patient.

Immediate provisional, staged final

Fitting a provisional prosthesis immediately avoids a period without teeth, and splinting the implants together helps protect them during early healing. Waiting six months before the final prosthesis allowed the soft tissues to mature and the bone to integrate before final records were taken.

The digital workflow

Computer-aided design and manufacturing has been reviewed as a way to fabricate dentures with fewer clinical appointments and more repeatable results than traditional methods.⁶ In this case, the digital records, verification model and milled monolithic prosthesis kept the process consistent from scan to delivery. A single-disc design also removes the step of bonding teeth to the base.⁸

Limitations

• This is a single case with [__ months] of follow-up. Long-term survival of the implants and prosthesis cannot be inferred from it.
• Insertion torque ranged from 15 to 35 Ncm, so primary stability varied between implants. Splinting the implants with a fixed provisional prosthesis and a careful loading and diet plan are the usual ways to reduce the load on lower-torque implants. [Confirm how the provisional occlusion and diet were managed]
• Smoking habits may change over time and are difficult to verify objectively.
• The outcome reflects this patient's anatomy and the team's technique, and may not be reproducible in every patient.

8. Patient perspective

[Add a short statement from the patient on comfort, chewing and confidence, with his permission.]

9. Conclusion

In this patient with a long smoking history, immediate extraction with six implants, an immediate provisional prosthesis and a digitally fabricated final prosthesis produced a fixed, functional and aesthetic result. Careful risk counselling, a staged protocol and a complete digital workflow were central to the plan. Long-term follow-up will be needed to confirm durability.

Why a multidisciplinary approach matters

10. Informed consent

The patient gave written informed consent for treatment and for publication of this case report and the accompanying clinical photographs and radiographs. Photographs are cropped to protect his identity.

Frequently asked questions

References

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