What is a basal implant? Disc implants, BOI and the corticobasal terms

First, the words themselves. The jawbone is not uniform: on the outside there is a hard, dense shell, known as cortical bone; inside, the structure is looser and spongy. The upper part in which the teeth sit is called the alveolar bone, and because it depends on the teeth, it resorbs after tooth loss. The lower, deep part that forms the body of the jaw is called the basal bone; it is much less affected by tooth loss. This is where the name 'basal implant' comes from: it describes the area in which the implant anchors, not a brand.

'Corticobasal' combines two words: the cortical shell in the basal area. According to Dr. Ihde Dental's own definition, a screw implant belongs to the basal implant group when it is anchored in the inner and outer walls of the bone together (bicortically) or in the second or third cortical layer, with cortical areas that resist resorption used by preference. The 'first cortical' is the upper shell the implant enters; the second and third are the opposing walls deeper down that the tip of the implant reaches. The name Corticobasal®, meanwhile, is used with a registered trademark symbol on the company's website; so it is both a general description and the name of a product group.

The first basal implants looked nothing like today's. implantate.com, a patient portal in Germany, writes that unlike all other types of screw implant, disc implants are placed into the bone from the side. According to the manufacturer's description, these laterally placed basal implants transfer chewing forces to the cortical bone via the upper and lower surfaces of horizontal base plates. In appearance, it is a disc laid into the bone at the end of a thin shaft.

The abbreviation BOI stands for 'basal osseointegrated implant', an implant that fuses with the basal bone. In 1999 a dental journal published in Switzerland carried a consensus text on BOI from a group of practitioners in Germany. In the same year, Stefan Ihde published an article describing the 'basal osseointegration' procedure in patients with a prominent lower jaw (Class III), writing that the prosthesis can be loaded early if the bone distribution is suitable, and that major surgery such as grafts from the hip bone is rarely needed. Ihde's book Principles of BOI, published by Springer in 2005, is also a product of this period.

Disc implants did not belong only to the Ihde circle. An article from Nice in France, published in 2012, describes basal disc implants in severely resorbed jaws. In this technique the implant site is 'activated' with a special instrument 45 to 90 days before surgery, and the fixed bridge is designed to be rigid enough to work like an external orthopaedic fixator. In other words, the name 'disc implant' describes a family of designs used by more than one school.

Then came the move to screw designs. According to the biography published on the International Implant Foundation's website, Ihde worked with laterally placed basal implants from 1996 to 2006 and has been working on the Strategic Implant® since 2006. strategic-implant.com writes that the term 'basal implant' was first used around 1999 and that the name Strategic Implant® is a protected term for the implants of Simpladent GmbH in Switzerland. Today's screw designs are placed from above like a conventional implant, but their tips anchor in the deep cortical wall. The sources do not explain the reasons for the change in detail.

The current status of disc implants should also be noted. According to implantate.com, the registered BOI trademark belongs to Biomed Est., and disc implants have been dropped from the manufacturer's catalogue. No disc-design implant appears in Dr. Ihde Dental's current product list either. So when a clinic today says 'basal implant', it most likely means a screw-type corticobasal implant; old disc implants are mostly found in the mouths of patients treated in the past.

The history of the words also holds an interesting contradiction. The name BOI contains the word 'osseointegrated', meaning fused with bone. Yet the International Implant Foundation's consensus text published in 2020 states that corticobasal implants achieve initial stability through 'osseofixation' rather than 'osseointegration', and that they work according to the principles used in treating fractures. Over the years, the same circle has changed the word it uses to describe its own method. The two concepts do not rule each other out; but knowing which one describes the first day and which describes what follows lets you read the terms correctly.

This is where the difference in terms from a conventional implant comes from. In publications, a conventional implant is often called 'crestal': the implant is placed in the bony ridge in which the teeth sit and gains its anchorage over time, as the bone fuses with its surface. A review published in 2026 compares the two groups as 'cortical' and 'cancellous' implants: basal implants anchor in dense cortical bone and are one-piece with a polished surface; conventional implants need enough alveolar bone and often staged treatment. We explain the method itself and its three core decisions separately in our guide 'What is an Ihde implant?'.

The words 'basal implant' in a quote or an advert tell you nothing on their own. The breakdown below helps you work out what the sentence you are reading actually means.

The questions below are a way of turning a general term into a concrete treatment plan.

1. 1

   Ask about the design: disc or screw

   Most of what is offered today is a screw design. Even so, asking which one is meant prevents misunderstandings from the start.

2. 2

   Ask for the name of the product

   Is it BCS, KOS, Strategic Implant® or another system? The product name determines which conditions of use apply.

3. 3

   See the anchorage point on the CBCT scan

   Which cortical wall each implant will go to, and at what angle, can be shown on the 3D image. The nerve canal and the boundaries of the sinus are assessed on the same image.

4. 4

   Ask what the loading decision is based on

   Fitting the teeth straight away depends on having enough mechanical anchorage from the first day. The anchorage is measured; an area that does not reach the expected value is not loaded that day, and delivery is postponed.

5. 5

   Ask for the record

   The product name, diameter, length and area should be given to you in writing. A document that just says 'basal implant' will not be enough for another dentist years from now.

There are other solutions that come up when bone is reduced. Some appear in the same sentence as basal implants but are different things.

Mixing up the words is not just a matter of language; it can lead to false expectations and an incomplete record.

How healing goes depends more on the extent of the surgery than on whether the design is a disc or a screw.

1. The first few days

   Swelling and bruising peak during this period and then subside. Cold compresses, sleeping with your head raised and the medication you are given keep this period manageable.

2. The first few weeks

   Your bite is checked and any spots that touch first are corrected. Chewing starts with soft foods and gradually returns to normal.

3. The first few months

   The gum settles around the new bridge. The tools you will use to clean under the bridge should become a habit during this period.

4. The long term

   At regular check-ups, the gum, the bridge and the bite are assessed. If you have an old disc implant, it also needs to be included in the follow-up plan.

We do not give figures; an accurate figure comes once the CBCT scan has been seen. In a plan carried out with basal implants, these are the items that determine the total:

Whether bone grafting is needed

When the anchorage can be taken from deep cortical bone, a graft does not come into it in most cases. This is the item where the biggest cost difference from the conventional route lies.

Number of implants

In plans that rely on load sharing, the number is usually kept higher. The number is set by the condition of the bone and the length of the bridge.

Bridgework

The final fixed teeth fitted on day three, with their material and workmanship, are the largest part of the total in most plans.

Planning and imaging

3D planning, in which it is decided which cortical wall each implant will go to, is an item this approach cannot do without.