Elimination of dental foci, installation of implants, the fabrication of metal ceramic arch bridge and screw-retained implant crowns (Case presentation) (72)

Our male patient, aged 55, reported to our clinic with the following requests:

• He desired to have his old neglected bridges replaced.
• He complained of foul breath.
• Several of his teeth in the left lower quadrant had recently been removed due to the great extent of inflammation around them, and he was now looking to have them replaced.
• He does not rule out the installation of implants.

Before

After

First treatment (3 workdays): tooth extractions
A digital panoramic radiograph was recorded at the first session and the condition of the teeth and periodontium assessed.

The panoramic radiograph recorded at the first encounter

The initial examinations revealed that all his lower molars were due for removal on account of pockets, inflammations and caries. The first examinations revealed that his lower molars were due for removal on account of the caries having formed under the crowns and inflammations. These inflammations are dental foci which need to be treated by all means since they may give rise to other non-dental issues (such as hair loss, dermatological, cardiological complaints, etc.). These tidings did not catch our patient unawares, although he was trustful that this could be avoided. He suspected major problems with his other teeth as well. He was even open to having implants mounted but would preferably go with bridges, if possible. Bridges are perfectly viable with upper teeth, but for a lower fixed restoration, implants are required due to free-end edentulisms. When restoring masticatory function, teeth up until the first molar need to be replaced, so that bits of food can be chewed properly to prevent the development of temporomandibular joint complaints and digestive disorders.

In the first step tartar removal and teeth polishing was performed due to the presence of a heavy pile-up of sub and supragingival tartar in order to prevent bacteria from entering the tooth extraction wounds and cause infection. The carious teeth were removed at the first treatment, that is, the dental foci were eliminated and a provisional denture was prepared for the lower jaw bone.

Second treatment following 3 months of healing (3 workdays) – the mounting of implants
Based on the principles of modern dentistry a CBCT (Cone beam computed tomography) scan was recorded.

A CBCT scan allowing the bone mass of the jawbones to be examined in 3 dimensions, the site and size of the implants to be assigned with the path of the inferior alveolar nerve duly taken into account.

The height and width of the bone were ideal for the installation of implants. Since the stability of the implant exceeded 30 Ncm on installation, the implant was covered with a healing abutment aka. gingiva former allowing the gums to heal into the perfect shape for the permanent abutment.

Follow-up panoramic radiograph of implants and healing abutments installed at the sites of lower-arch edentulisms

Following implantation, the provisional denture was relined with a soft material (soft reline) for ease of wear during osseointegration. In the course of healing, remember to thoroughly clean your natural teeth and provisional dentures as well as the gingiva formers with a soft bristle toothbrush.

Third treatment: the fabrication of metal ceramic crowns and bridges for natural teeth and implants (10 workdays)

Following 3 months of healing (osseointegration) we were able to set about the fabrication permanent crowns for implants and natural teeth. Our patient’s choice fell on metal ceramic crowns and he would favour a screw-retained bridge for the 3 implants installed per lower quadrant. With such major aesthetic restorations, a minimum of 10 days is required for the dental technician to deliver superior workmanship and shape the tiniest details of the replacement teeth to “artistic” perfection. If the dental technician has insufficient time for the fabrication of the replacement teeth, that may compromise aesthetics. Please observe the recommendations as to the number of treatment days at all times for the best possible results.

Following the removal/ cutting off of old crowns and filing/preparation of teeth the gingiva formers/healing abutments were unscrewed from the implants and precision impressions were taken of the tooth preparations and implants.

The tooth preparations receive provisional crowns (using the Scutan method). These provisional crowns protect the filed-down tooth stumps and provide reasonable aesthetics until the permanent crowns are finished. The provisional crowns are different from the crowns handed over at the end of the treatment. Impression taking is followed by a so-called gnathological treatment, that is an instrument-aided bite registration, for the dental technician to see the occlusal position of the temporomandibular joints in the articulator and mould the future replacement teeth accordingly.

Articulator: the articulator is a dental instrument reproducing the movements of the mandible and the maxilla, “mimicking the patient’s head” in the dental laboratory, as it were, without the patient actually being present.

The precision impressions are followed by several trial fittings.

First trial fitting: During the trial fitting of the framework the precision impressions and metal frameworks of the crowns are verified for accuracy, since all future replacement teeth must seamlessly fit the master cast. During this trial fitting not only the frameworks of natural teeth-borne crowns are tested, but also the implant-borne crowns and abutments are checked for trueness.

Second trial fitting: at the trial fitting of the matte teeth the crowns are almost complete with the ceramic already sintered on. This trial fitting allows for a closer verification of occlusion (function) and the shape, colour, centre line and the smile (aesthetic trial fitting). If no adjustments are required (both function and aesthetics leave nothing to be desired) the dental technician completes the crowns by coating them with a glossy finish (glaze). Once this final glossy finish is burnt on, the crowns are ready to be glued on.

Between the different work phases and trial fittings several days may intervene, during which the dental technicians are working on the replacement teeth.

The permanent cementing of the crowns is a meticulous process occasionally requiring anaesthetics when cementing or screwing the crowns and bridges in place.

Anaesthetics often hinder the “fine-tuning” of occlusion as the patient does not have a precise sensation of the height of the new crown or bridge, which may necessitate another appointment for the dentist to check and adjust occlusion. These appointments are crucial as an inappropriately adjusted occlusion may result in overload or pressure to the crowns and exhaust the muscles, which may bring on tooth clenching or tooth grinding at night. Overload, on the other hand, may subject the temporomandibular joints to undue wear and compression, which may entail toothache and the chipping off of ceramics.

When the permanent bridges were glued on and the screw-retained implant bridges were screwed in place and occlusion was precisely adjusted our patient was immensely satisfied with his new teeth and smile.

He was advised on the importance of home cleaning and regular check-ups and was shown the accessories of home cleaning and their use (interdental brush, dental floss, Super Floss), all of which are essential for the long-term success of replacement teeth.

Before

After

Before

After

Before

After

Before

After

Before

After