Full Mouth Dental Implants (All-on-4 and All-on-6)

Full Mouth Implants Carry a Whole Arch on Four or Six Implants

A jaw without teeth does not need one implant per missing tooth. In full mouth dental implant treatment, every tooth in the arch is joined in a single fixed bridge, and that bridge is screwed onto four implants (All-on-4) or six (All-on-6); this is where it differs from single tooth implant treatment. You do not take the bridge out yourself; the dentist loosens the screws to remove it at check-ups.

Losing every tooth in a jaw is common. Pooling 86 papers with 17 national surveys of adults aged 45 and over, a meta-analysis estimated that 22% had no natural teeth left (PubMed 36265526). Maló first described the four-implant concept in 2003, and Huber and colleagues report that severe tooth loss affects roughly 267 million people worldwide (PubMed 42782928).

The number of implants is not something to pick from a package name. An overview of systematic reviews on the toothless upper jaw concluded that a one-piece fixed bridge can be carried by at least two upright front implants plus two tilted back implants, or by six to eight upright implants spread evenly around the arch (PubMed 33571327). Which of these suits you is decided by the examination and a 3D CBCT scan together.

All-on-4 and All-on-6 Compared

The two plans differ in how many implants carry the bridge and where they sit. All-on-4 uses an upright front pair and an angled back pair. Angling the back implants moves their tips away from the sinus in the upper jaw and the nerve canal in the lower jaw, and gives each one a longer stretch of bone to grip. In All-on-6, six implants are spread along the arch so that chewing load is shared between more points, which requires enough bone at the back to hold the two extra implants.

Pooled results are close. Shao and colleagues combined 55 studies: beyond 5 years, implant survival reached 98.14% with All-on-4 and 97.50% with All-on-6, and bone loss at 5 years measured 1.28 mm and 0.94 mm (PubMed 42031576). A multicentre randomised trial comparing the two designs in the upper jaw placed 233 implants in 47 patients and found no significant difference in bone level change at 5 years (PubMed 39581887).

Where they part is on the prosthetic side. The trial recorded technical complications at a rate of 16.6% against 0%, to the disadvantage of the four-implant group, while initial and total costs favoured four implants (PubMed 39581887). A separate meta-analysis of 53 studies found similar implant and bridge survival in both groups, but significantly more marginal bone loss with four implants (PubMed 38317918). A fuller comparison is in our article All-on-4 or All-on-6.

Bone Volume and Bite Load Decide the Plan

The CBCT scan is the first piece of evidence. It shows the height and width of the bone and the position of the sinus in the upper jaw and the nerve canal in the lower jaw. Six implants need adequate bone as far back as the molars. If the back of the jaw has thinned, angled implants can be anchored in the firmer bone towards the front while keeping away from the sinus or the nerve. Where even four implants would not have enough bone, the options are a bone graft, raising the sinus floor, or zygomatic implants fixed in the cheekbone.

The safety of tilted placement has been measured. An umbrella review of meta-analyses found a relative risk of failure of 1.02 (95% CI 0.85-1.23) between tilted and upright implants, with a long-term bone loss difference of 0.18 mm (PubMed 38941170). An earlier meta-analysis of 44 publications found no overall difference, but when only upper jaw studies were pooled the relative risk rose to 1.70 (PubMed 25239770), which is why tilted implants in the upper jaw are planned with particular care.

Other factors count as well. If the opposite jaw has your own teeth or a fixed bridge, if you grind at night or if the bridge runs far back, spreading the load over more implants may be justified. The number alone has not been shown to change survival: a meta-analysis of 93 studies found no significant difference in implant or bridge survival between fewer than five and five or more implants per arch (PubMed 30328199).

Who Full Mouth Implants Are For

The treatment is considered for people who have lost every tooth in a jaw, or whose remaining teeth cannot be saved because of advanced gum disease or decay. If some teeth can be kept, a partial implant or bridge plan that keeps them is weighed first. Huber and colleagues describe All-on-4 as a reliable option for patients with advanced bone loss who prefer to avoid bone augmentation or a removable denture (PubMed 42782928). Options that clip onto implants but come out for cleaning are covered on our dentures page.

Where teeth were lost to periodontitis, gum inflammation is brought under control before surgery, since the same bacterial process can continue around implants. Diabetes control, regular medication and smoking are discussed at the examination. In a meta-analysis of 89 publications, implants in people with diabetes had an odds ratio for failure of 1.777 (PubMed 35591561). For smokers, the odds ratio across 292 publications was 2.402 (PubMed 35056347). In both cases the plan and the frequency of check-ups are set to match the risk.

What a Full Mouth Implant Package Should Include

A full mouth implant package in Turkey usually combines the clinical work with the arrangements for your stay. On the clinical side it commonly covers the examination, X-rays and a CBCT scan, any extractions, the implant surgery, an interim bridge worn while the bone heals and the final bridge.

A package name says little on its own, because two offers both called All-on-4 can describe different treatments. Before booking, ask for a written plan that names the design, the number of implants, the implant system, the material of the interim and final bridges, and whether extractions, bone grafting or a sinus lift are included. Grafting and a sinus lift change the calendar as well as the plan, so it matters whether they sit inside the quote or would be added later.

The plan should also state what happens once you are home: adjustments, repairs to the interim bridge, re-tightening of screws and how follow-up runs between the two trips. In a series of 192 immediately loaded arches, 17.7% of acrylic interim bridges needed at least one repair during treatment (PubMed 26848820), so it helps to know in advance how a repair would be handled. Ask for the implant system and lot numbers to be recorded in your file; traceable components make spare parts easier to source later.

At Mosdent the itemised plan, including the implant count, the bridge material and the number of visits, is issued in writing after the CBCT scan is read. Two written quotes can be compared line by line when the design, implant count, implant system and bridge material match; when those lines differ, the comparison is between two different treatments.

Treatment Process

1. 01Examination and CBCT: Bone volume, the opposing jaw, remaining teeth and general health are assessed; implant count and angles are planned on a 3D scan.
2. 02Surgery: Unsavable teeth are extracted, then four or six implants are placed with local anaesthesia or sedation.
3. 03Interim Fixed Bridge: If the implants are firmly stable at placement, an interim fixed bridge is screwed on; if not, they heal without load.
4. 04Final Bridge: Once integration is confirmed on X-ray, records are taken and the final hybrid bridge is screwed onto the implants.
5. 05Check-ups: The dentist removes the bridge when needed; the tissue around the implants, the screws and the bite are checked regularly.

Surgery Day and the Interim Bridge

At the examination the dentist records bone volume and density, the opposing jaw, your bite and any remaining teeth, and schedules extractions where needed. The CBCT scan sets the angle and length of the tilted implants, and in a six-implant plan the position of the extra pair.

Surgery can be done under local anaesthesia or with sedation. Teeth that cannot be saved are removed in the same session and the implants are placed at the points planned on the scan. Whether an interim bridge can be fitted that day depends on how firmly the implants are held at placement. In Drago's series of 192 toothless arches, immediate loading required at least 35 Ncm of insertion torque per implant (PubMed 26848820). Across 62 studies and 13,653 implants, most authors recommended a minimum of 30 Ncm for immediate loading, and estimated 1-year implant survival was above 99% with immediate, early and conventional loading alike (PubMed 24660202). If the threshold is not reached, the implants heal without load.

The same-day bridge is an interim one, made to restore appearance and speech while the bone heals, and it is not built for hard biting. In Patzelt and colleagues' review of 13 studies, 1,201 bridges were fitted on 4,804 implants within 48 hours of surgery (PubMed 23560986).

From the Interim to the Final Bridge

Under conventional loading, implants are kept free of load for 3 to 8 months to integrate with the bone (PubMed 23543525). Once integration is confirmed on X-ray, new records are taken for the final bridge; at Mosdent full-arch implant positions are measured with IMETRIC photogrammetry. A systematic review comparing photogrammetry with intraoral scanning found higher accuracy with photogrammetry in 10 of 13 studies, and its authors call for further clinical trials before firm conclusions (PubMed 40481748).

A full-arch case is normally planned across two trips: the scan, surgery and interim bridge on the first, and the final bridge after integration on the second. The final hybrid bridge can be made in PMMA, porcelain or zirconia, chosen according to the opposing jaw, any grinding habit and your aesthetic goals. In a meta-analysis of 41 studies, the bridge material made no clinically relevant difference to implant or bridge survival, while chipping occurred in 8% of metal-ceramic, 15% of all-ceramic and 22% of metal-resin bridges (PubMed 30871937). According to Shao and colleagues, zirconia bridges may cut down mechanical complications (PubMed 42031576).

Full Mouth Restoration: Planning Both Jaws

When teeth are missing in both jaws, the upper and lower arches are planned together as a full mouth restoration. Because the two bridges bite against each other, tooth length, bite height and the smile line are set in one design. The upper jaw might receive a fixed bridge, for example, while the lower jaw keeps your own teeth or an implant-retained denture; whatever the other jaw holds influences the implant count and the bridge material.

Results in the two jaws are similar. Gaonkar and colleagues reviewed 25 All-on-4 studies and found cumulative implant survival between 94% and 98% at 72 to 132 months; survival did not differ significantly between angled and upright implants, nor between upper and lower jaws (PubMed 33835063). In the lower jaw, a meta-analysis of 17 prospective studies with at least 5 years of follow-up found cumulative survival of 98.42% at 5 years and 96.86% at 10 years for rough-surface implants, and the number of supporting implants did not affect survival (PubMed 23311617).

Planning still differs between the jaws. The sinus sits above the back of the upper jaw. For that jaw, an overview of systematic reviews recommends a minimum of four implants under any implant prosthesis, fixed or removable (PubMed 33571327). The order in which the two jaws are treated is agreed at the examination. The wider treatment process is described in our full mouth reconstruction article.

Long-Term Results and Maintenance

Over the long term, care of the bridge shapes the result as much as the implants do. An umbrella review of systematic reviews with at least 5 years of follow-up reported full-arch bridge survival of 89.5% to 96.8% over 5 to 15 years and implant survival of 95.2% to 99.2% (PubMed 41927400). The same review found screw loosening in 5% to 15% and veneer chipping in 15% to 35% of veneered zirconia bridges, and no survival difference between 4 and 6 implants (PubMed 41927400). An earlier review of 24 All-on-4 studies reported 99.8% survival beyond 24 months, while noting that only one study reported a sample size calculation and that follow-up was often inadequate (PubMed 28298995).

The side of the bridge facing the gum and the implant necks are cleaned every day with interdental brushes, thick floss or a water flosser; which one fits under your bridge is agreed after the final bridge is fitted. At check-ups the bridge is removed so the implants and screws can be examined. In Derks and Tomasi's review of 11 studies, the weighted mean prevalence of peri-implant mucositis was 43% and of peri-implantitis 22% (PubMed 25495683). If you grind your teeth, a night guard can reduce the load on the bridge at night.

Patients' own assessment has been studied too. A review of 11 studies covering 693 patients with four-implant fixed full dentures found high oral health-related quality of life and satisfaction, while the authors note that the quality of evidence is still limited (PubMed 34647147).