Bar-retained overdentures mounted on 4 implants for patients suffering from periodontal disease (Case presentation) (62 )

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Bar-retained overdentures mounted on 4 implants for patients suffering from periodontal disease

Our patient reported to Suba Dentál clinic with the following requests:

He had previously lost his upper teeth and some of his lower teeth due to chronic uncontrolled periodontitis.
He is aware that the lower ones are also in ill repair and probably in need for extraction.
Since his periodontal disease had already caused a great extent of bone loss he knew that a fixed solution could only be viable with a major bone graft, which he did not desire in the least.
He would be completely satisfied with an implant-borne removable denture which does not require bone graft.

First treatment: extraction of teeth and the complete elimination of dental foci, fabrication of (immediate) provisional denture (3 workdays)

At the first encounter our patient showed up with a panoramic radiograph recorded at an other clinic, so no radiography was required. The clinical examination and the panoramic radiograph revealed that the teeth were indeed in a very poor condition and beyond repair.

Panoramic radiograph with the dental foci and teeth afflicted with chronic periodontal disease

Had his periodontal disease been treated several years earlier and the sub- and supragingival tartar removed at least twice a year, his gums, teeth and jawbone would not have fallen into such a state of disrepair, and his teeth could have been kept for much longer.

Lower teeth with visible pile-up of tartar and receded gumline

Our patient was prepared for such tidings: he was not caught unawares. We discussed his options for tooth restoration and our choice fell on bar dentures. Fixed restoration was impracticable due to the great extent of bone decay other than by bone graft, which our patient was against. The installation of 4 implants, on the other hand, was perfectly feasible based on the preliminary examinations. Of course, a full-fledged treatment plan was only due 3 months after the tooth extractions when a CBCT (Cone beam computed tomography) scan was made.

During the first treatment all his remaining lower teeth were extracted and all dental foci eliminated. Once the teeth were extracted, an immediate denture was fabricated at the chairside, so the patient is not left toothless over the 3 months of healing and would be able to smile, socialise and eat without his self-esteem and quality of life being compromised. Prior to tooth extractions, PRF technology ways used, that is, previously drawn blood specimens were centrifuged and the fibrin clots were placed at the sites of the extracted teeth. This promoted healing, as a result of which our patient complained of no pain whatever at the follow-up session the day after.

Further details on PRF technology

Further details on the cleaning of removable dentures

Treatment phase two: dental implant surgery, reline of removable denture (3 workdays)

Following 3 months’ healing time the treatment could be resumed with the installation of implants (4 implants for the upper and lower arch each). A CBCT (Cone beam computed tomography) scan was recorded for a 3 dimensional examination of residual bone mass for the thorough planning of the sites and sizes of the implants.

Besides stability, bar dentures also have the great benefit that implants can be aligned with the bone mass, and axial discrepancies can thus be remedied with implant-retained bars, which eliminates the necessity of a bone-graft. The CT scan proved our preliminary planning to be viable so we could set about the installation of the implants. The 4 implants for the upper and lower arch each were therefore installed in one sitting and, at our patient’s request, PRF technology was applied. following implants surgery, the removable provisional dentures were relined in keeping with the altered anatomical relations to ensure comfort of wear during the 6 months of healing.

Further details on the reline of a provisional denture

Treatment phase three: the fabrication of the permanent bar dentures (10 workdays)

Following six months’ healing time we could begin the final and lengthiest treatment, that of fabricating the permanent replacement teeth attaching to implant-borne bars Thanks to gingiva formers (healing abutments) precision impression taking can be performed in a simple and almost painless way. Following the removal of the gingiva formers, so-called impression copings are screwed in, which give the dental technician exact information as to the location and axial position of the dental implant installed in the bone. A follow-up panoramic radiograph is made to verify the seamless fit of the impression copings in the implants.

Following impression taking a gnathological treatment (viz. an instrument-aided bite registration) is due for the technician to see the exact position of the jawbones in the articulator to ensure the correct position of the temporomandibular joint on occlusion.

With dentures, not to mention bar dentures, several crucial trial fittings are performed for the dentures to seamlessly fit and to achieve perfect aesthetics. The trial fittings are performed at varying intervals, sometimes with 2 trial fittings performed a day, but sometimes with several days in between two trial fittings.

During the trial fitting of the bar the finished bar is screwed into the implants following removal of the healing abutments to verify the trueness of the framework of the tooth restoration.

The trial fitting of teeth focuses on aesthetics and correct occlusal position. During the trial fitting of teeth, aesthetics can be improved at the patient’s request with regard to the position and shape of the teeth. Since the teeth at this stage are embedded in wax, the dental technicians can easily move them around.

At handover, the bars are screwed onto the implants with the appropriate torque and the permanent denture will seamlessly sit on them.

Our patient left satisfied with the treatments and happy with his new teeth. In order to preserve warranty, reporting for regular check-ups, oral hygiene treatments and professional tartar removal are mandatory. The patient was informed as to the importance of keeping the denture clean and basic routines of keeping it clean. Preferably, dentures should be removed after each meal and cleaned thoroughly with a denture brush. The implants and the bar must also be cleaned thoroughly and daily with a tooth brush, toothpaste, as well as beneath the bar, with Super Floss and an interdental brush.

The bar mounted on 4 lower implants on the master cast

Lower bar denture secured with MK1 hidden attachments

Bar and artificial gums intended for 4 upper implants

Upper bar denture on the master cast with MK1 attachment

Bars offer such a degree of stability that dentures sit firmly even without the support of the roof of the mouth, making it an ideal solution for those unable to wear palate-supported dentures.

The small orifice into which a key can be inserted to open the hidden MK1 attachment system. The denture can only be removed by opening the small latch with the key