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Ball implants vs Locator attachments as effective solutions for an unstable overdenture prosthesis

Ball implants vs Locator attachments as effective solutions for an unstable overdenture prosthesis

Implants with ball retainers an Locator attachments on the lower jaw are an efficient solution to avoid the instability of a total prosthesis, especially for those patients with a big tongue (macroglosia) and little bone ridge retention.


Actually, the tongue tends to grow as we grow old, and even more when we lose teeth, because the leave more place for the tongue itself.
With the tongue movements, the prosthesis comes loose easily and that is usually uncomfortable for the patients because of the lack of confidence on the prosthesis while eating or speaking.

The lower jaw keeps normally enough bone on the anterior region, even in very atrophic cases. This case, from a 77 year-old male, shows more than enough bone kept. So 3 ICX implants, all three 15” x 3,75” were easily set on the most conveniet places of the lower anterior region.

The remainig lower left wisdom tooth was left in place. At 77 years of age and without sympoms and no influence on the therapie, it can as well stay in place.

So, after two months the healing caps are changed by ball retainers and the old prosthesis is relined in order to fit the new conectors.

The prosthesis is marked below, exactly where the contact points are.

Then comes the drilling until the prosthesis rests freeely on the gums.

Reline resin is added under the prosthesis. The patient bites in the normal position and the resin selfcures in the mouth.

The rubber rings inside the stainless steel structure can be chosen in three differente degrees of hardness and retention. They wear out like every rubber component and can be therefore easily changed.

After a few minutes cure time the retainers are already fixed and the retaining force can already be appreciated, as the prosthesis stays in the right position although the tongue and the cheeks exert the same force as before.
In this case, the three ball retainers proved not to be retentive enough for the patient. Normally a four implant solution provides a more retentive, more stable, four-point trapezoidal support. Nut the patient was running on a low budget and we had to go for a three implant display, with the central implant close to the mandibular synfisis. 
By changing the three ball retainers into Locator attachments and just placing the softer plastic rings under the metal matrixes, we achieved a good degree of confort for the patient.
Delayed implants after total extractions. Periodontal disease.

Delayed implants after total extractions. Periodontal disease.

This case presents severe periodontal disease. The only logical treatment plan is full extractions and new denture.

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The virulence of the periodontal affection and the severe bone ridge damage, with too many irregularities, suggest a prudential approach for the implant surgery. I prefer having the teeth extracted and wait until the bone ridge is in better, safer shape and the bacteria in the mouth have cleared up.

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So, the patient is sent to her general dentist for full extractions and temporary denture placement.

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We wait 4 1/2 months, with periodical checks to prevent from a sudden ridge collapse. The longer the wait, the safest the implant surgery (more regular bone and healthier flora), but you have to be ready for an eventual fast bone resorption that may be the signal to program an immediate implant surgery, not to lose much bone height or width.

The ridge is amazingly flat, but extremely deceiving for its concavity. The earlier thrust of a macroglosic tongue left an alveolar protrusion in both maxillas. IMGP1248

In order to prepare an optimal fitting and esthetic prosthesis. I place the implants as parallel as possible, taking care not to perforate the vestibular bone, but sometimes, it happens.

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If the space is limited, bone graft and membrane should be used to cover the vestibular defect and still keep the implant in the same place. But in this case there is plenty of space to insert the implant somewhere else.

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Two weeks later I proceed to the upper maxillary implant surgery. The bone has a more rounded ridge and not as much concavity, but enough as to need a change in placement. The higher the number of implants, the bigger need for their parallelism. But, the angle that works fine in one bone section may not be as good in another portion of the bone. And perforations can happen. This could be prevented by CAD-CAM designed surgery, but it is also costly. It can be done with a little personal 3D view and surgical resources.

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This is the final result after 6 months, ready for his general dentist to initiate the fixed prosthesis.