Oral Health Group
Feature

Full Mouth Rehabilitation: Correcting for Severe Wear and Cant


By Dennis Springhetti, DDS and Mr. Chang Kim, RDT, MDT

Both the dentist and the patient experience a great deal of joy and excitement when a smile is restored. As Dr. David Hornbrook says, “The patient is truly receiving a gift”. With severely worn teeth in a young man, a new smile is really a life altering experience.

This was exactly the case with a 37-year-old male patient in Dr. Springhetti’s practice. In 1992, there were the beginnings of some sign of nocturnal bruxism demonstrated by wearing of his canines and the loss of cuspid rise in posterior disclusion. The patient attributed this wear and chipping to trauma from playing football. As the patient did not want to deal with this restoratively a splint was suggested to prevent any further wear. This patient disappeared from the practice.

In 2002, the patient returned after becoming frustrated with the severe wear that had taken place. Significant tooth structure was lost. The lower left first molar had been lost due to a vertical fracture and the lower right first molar had received a root canal and crown due to chronic pain. Because very little other restorative dentistry was present, possible centric relation interferences traumatized the lower first molars and the resultant avoidance of these may have been responsible for the anterior wear. A skeletal cant was also observed with considerably more wear in the first quadrant, which made it look even worse (Figs. 1-3).

The treatment plan, developed in conjunction with Mr. Chang Kim and Prowest International Dental Services Ltd., included full mouth reconstruction in an orthopedic stable position. This was to be done in several stages. The first stage included addressing the aesthetic concern as well as achieving harmony in the muscles of mastication. Stage two was to complete the molar restorations. It was explained to the patient that he may be an habitual bruxer (Figs. 4A & B) so a post-op splint would be required to protect the restorations.

Because of the extensive tooth wear, it was decided to open up the patient to 17.5mm CEJ-CEJ (Fig. 5). Pre-treatment CEJ-CEJ was 12.5mm (Fig. 6). This increase in vertical dimension would give us room to restore form and function to the dentition.

To address the canting problem, osseous correction was dismissed by the patient. Respecting biological width, a gingivectomy was performed from 11-25 in order to give the illusion of symmetry. Adding length to the teeth in the first quadrant gave a very satisfactory result.

The final restorative occlusal relationship was determined using a deprogramming splint for 24 hours. Bi-mandibular manipulation was used to obtain a centric relation bite record. Joint noises were recorded pre-operatively, with a splint in place, with the temporaries in place and with the final restorations. The results showed a decrease in their values. The centric relation record was transferred to an articulator and the upper and lower wax-ups were constructed (Fig. 7).

An intraoral mock-up (Fig. 8) was done in composite on the maxillary teeth in order to determine central incisor length and position following principles of Dr. Hornbrook’s smile design. The correction of the canting issue was also addressed. Once the patient and dentist were satisfied, an impression duplicated the mockup (Fig. 9) for Prowest to use as a guide for the wax-up. Facebow (Fig. 3), stick bite (Fig. 10) and stumpf shade (Figs. 11A & B) were taken and sent to Prowest. Shade was discussed with the patient and a very bright warm combination was selected (Fig. 12). The lab fabricated a number of siltech and clear stints in order to ensure adequate removal of tooth structure and enough room for porcelain (Figs. 13-19).

Maxillary upper 10 teeth and lower 11 (35-37 bridge was removed and included in stage I of the restorative plan) (Fig. 20) were prepped as conservatively as possible. Because the upper posterior and lower right posterior molars were not prepared at this time, the centric relation bite record was used to maintain the bite relationship throughout.

As the quadrants were prepped, new bite relation records were taken including prepped to pre-op, prep-to-prep and prep to temp (Fig. 21). This way the laboratory was able to inter-mount all models: pre-op, wax-up, master impressions and temporaries. A stick bite was taken along with photo so the lab could verify the incisal edge position with the ears and eyes (Fig. 22).

Temporaries (Figs. 23-24) were fabricated using siltechs of the wax-ups (Fig. 25). The bite was then adjusted.

One month later, the follow-up showed the patient was asymptomatic and very comfortable both functionally and aesthetically (Figs. 26-39). The upper 10 IPS Empress all porcelain restorations were bonded in using “the Hornbrook Tack and wave” technique and then the lowers. The bite was adjusted and impressions were taken for a new splint.

CONCLUSION

Placing the patient in an orthopedic stable position worked very well for this young man. Prepping the anterior/intermediate sections first eliminated any posterior interferences that may have been a reason for his anterior wear. Future treatment will include Stage II consisting of centric occlusion dentistry on the remaining molars, as CR now equals CO. The patient’s bite will continue to be monitored and adjusted as necessary. The non-osseous correction of the cant through lengthening quad 1 dentally and gingival recontouring in the second quad gave a very satisfactory result.

Dr. Dennis Springhetti is a graduate of University of Alberta. He maintains a private practice in Calgary, AB.

Mr. Chang Kim, RDT, MDT, is a graduate of the University Hospital in Seoul, Korea, and the University of New York masters program. He is an accredited member of the American Academy of Cosmetic Dentistry. He is president of Prowest International Dental Services Ltd.

Oral Health welcomes this original article.