What Both Treatments Have in Common
All-on-4 and All-on-6 are both full-arch dental implant solutions — treatments designed to replace an entire upper or lower set of teeth using a fixed bridge supported by implants. Unlike traditional dentures, which sit on the gum and can be removed, both treatments produce a permanent, fixed result that functions and feels much more like natural teeth.
Both treatments have become widely available in Turkish dental clinics, and they are among the most commonly requested procedures by UK patients seeking full-arch tooth replacement. Understanding how they differ — and what determines which is appropriate — helps patients have more informed conversations with their chosen clinic.
All-on-4: The Four-Implant Approach
All-on-4 uses four implants to support a full arch of teeth. The key design feature is the placement angle of the two rear implants: rather than being inserted vertically, they are placed at an angle (typically around 45 degrees) into the denser bone at the front of the jaw. This angulation serves two purposes: it allows the implants to reach more bone, and it avoids anatomical structures such as the sinus cavity in the upper jaw or the nerve canal in the lower jaw.
All-on-4 was specifically developed by implant researchers to help patients with reduced bone volume — people who might otherwise have been told they needed extensive bone grafting before any implant could be placed. By angling the rear implants and anchoring into better-quality anterior bone, the technique allows more patients to receive fixed teeth without the additional time and cost of grafting.
All-on-4 often allows for immediate loading — meaning temporary teeth can be attached on the same day as implant surgery. The permanent prosthesis is fitted once osseointegration (bone fusion) is confirmed, typically several months later.
All-on-6: The Six-Implant Approach
All-on-6 follows the same concept — a fixed full-arch bridge supported by implants — but uses six implants rather than four. The additional two implants provide more support points across the arch and can improve the distribution of bite force across the prosthesis.
All-on-6 is often considered where the patient has adequate bone volume to accommodate six implant sites. More implants can mean better long-term support for the prosthesis and potentially a stronger structure for patients with higher bite forces or a wider jaw. Some clinicians prefer six implants where bone quality is good, arguing that the additional support reduces stress on each individual implant.
How Bone Distribution Determines the Choice
The choice between All-on-4 and All-on-6 is not arbitrary — it is driven by what the patient's bone anatomy can support. Bone volume varies significantly between individuals, and in the same patient it often varies between the upper and lower jaw. Patients who have been without teeth for some time typically have less bone than patients with more recent tooth loss, because bone resorbs when teeth are absent.
A patient with significant bone loss across the posterior arch may be a better candidate for All-on-4, where the angled placement compensates for limited bone in the back of the jaw. A patient with good bone volume across a wider area may benefit from the added stability of six implants. Some patients receive All-on-4 in one jaw and All-on-6 in the other, based on the different bone conditions in each arch.
The Role of the CT Scan
The only reliable way to determine which approach is appropriate for any individual is a cone beam CT (CBCT) scan. This produces a three-dimensional map of the jaw, showing bone volume, bone density, and the position of anatomical structures that affect where implants can safely be placed.
A clinic that provides a firm All-on-4 or All-on-6 recommendation without CT imaging is making a clinical decision without clinical evidence. Any reputable clinic will conduct a CT scan — or request your existing scan — before confirming the treatment plan. Do not treat a quote that specifies All-on-4 or All-on-6 as a confirmed plan until the diagnostic imaging has been reviewed.
The Treatment Process
For both treatments, the process typically involves an initial consultation and CT scan assessment, implant surgery, a period of healing and osseointegration (usually three to six months), and then fitting of the permanent prosthesis. During the healing period, temporary teeth are usually provided so that patients are not without teeth.
This means the treatment involves at minimum two visits to Turkey — one for the implant surgery and one for the permanent fitting. Some clinics offer the complete process in a single extended visit for certain patients, but this depends on clinical assessment and individual healing response.