Treatment of Severe Dental Erosion Utilizing Direct Composite to Phase Treatment

Dental erosion is a common cause of tooth wear, yet patients may report that their dentist is "watching it" or decline treatment because the condition is not painful. If the cause of the erosion is eliminated and the lesions are treated early enough, the treatment can be as simple as using a small resin restoration to cover the dentin.¹ In severe cases, the treatment can be complex and may require opening the patient's vertical dimension of occlusion (VDO). Such cases necessitate a systematic treatment plan that is predictable for both the dentist and the patient.

This case demonstrates the treatment of severe erosion using a carefully implemented diagnostic and risk assessment protocol. Use of this protocol allowed treatment of functional and esthetic needs to be delivered to the patient in phases, with each phase lowering the patient's risk of oral disease.^2,3

A 59-year-old male patient arrived at a community health clinic with swelling and pain on tooth No. 8. The tooth was diagnosed with a chronic apical abscess and treated with endodontic therapy. When the patient returned for a comprehensive examination, his chief concerns were the esthetics and deterioration of his teeth. He had noticed that teeth Nos. 6 and 9 through 11, which used to be the same length as the crowns on teeth Nos. 7 and 8, were now shorter (Figure 1). Teeth Nos. 7 and 8 had base-metal partial-coverage crowns, which had been placed in Mexico approximately 20 years prior to presentation. These crowns were placed to treat caries and dentin exposure palatally, according to the patient. A comprehensive examination was completed with clinical photographs.

Pertinent medical history included hypertension, gastroesophageal reflux disease(GERD), and type 2 diabetes. The hypertension and diabetes were controlled with medication and diet. The patient reported that his GERD symptoms were occurring less frequently over the past 5 years since he was avoiding trigger foods that had caused regurgitation. Given the extent of dental erosion, he was referred to a gastroenterologist for re-evaluation to confirm the GERD was controlled.

In his dental history, the patient reported that he had not received regular dental care during his lifetime. He had noticed holes and pitting on the occlusal surfaces of his teeth and chipping of his front teeth. His left temporomandibular joint (TMJ) had an asymptomatic click that he reported had been present for more than 20 years. He was self-conscious about the color and worn appearance of his teeth.

Periodontal: The patient presented with generalized 1 mm to 2 mm of radiographic bone loss. He had no bleeding on probing and minimal plaque and/or calculus. Tooth No. 8 had a distal probing depth of 8 mm with purulence. His mandibular molars exhibited 4 mm of radiographic bone loss and class II furcation involvement. Based on his clinical presentation, he would have been considered American Academy of Periodontology (AAP) stage III, grade C, but because of his type 2 diabetes his diagnosis was AAP stage IV, grade C.⁴

Risk: High

Prognosis: Generally fair; No. 8 poor/hopeless; mandibular molars poor

Biomechanical: Examination revealed interproximal caries on teeth Nos. 4 and 15. There was a defective composite restoration on the distal aspect of tooth No. 20. The crown margins on teeth Nos. 7 and 8 were questionable and most likely had cement failure. Moderate dental erosion was present throughout the mouth, with severe dental erosion evident on teeth Nos. 6, 9 through 11, and 20 (Figure 2 and Figure 3). Structural compromises were present on endodontically treated teeth Nos. 6, 8, and 13. An amalgam filling in tooth No. 14 also presented a moderate structural risk. Tooth No. 8 was considered high risk endodontically due to the persistent fistula post-treatment. Teeth Nos. 19 and 30 had been extracted more than 20 years prior because of a large amount of caries and pulpal problems.

Risk: High

Prognosis: Generally poor because of extensive erosion; areas of active caries hopeless; tooth No. 8 also hopeless due to failed endodontic therapy

Functional: Asymptomatic disc displacement was present in the left TMJ, but because it had been stable for more than 20 years it was not expected to affect treatment. The patient had a normal range of motion of 45 mm. A load test and immobilization test were negative. He had low to moderate amounts of attrition on his posterior teeth and severe attrition on his anterior teeth. The main cause of the attrition was determined to be the intraoral acidity caused by GERD. If function was the main cause, the patient would have had flat incisal edges on his natural maxillary anterior teeth instead of thin enamel projections.⁵ Given the clinical findings and the negative answers to the functional section of the dental history, a diagnosis of acceptable function was made.

Risk: Moderate

Prognosis: Good

Dentofacial: The patient's Duchenne smile showed moderate lip dynamics (Figure 4), with his smile line going just up to the free gingival margins of the lateral incisors and canines. This assessment proved to be a key component in the clinician's final treatment plan, as the patient did not like his smile because of the uneven wear and color of his teeth and the metal display. He desired to replace the existing metal crowns with porcelain for a whiter and more uniform smile.

Risk: Moderate

Prognosis: Poor

The primary treatment goal was to stabilize the patient's dentition. This would be achieved by treating the periodontal disease, reducing the biomechanical risk by addressing the non-healing abscess on tooth No. 8, and protecting the teeth from further erosion, all of which would also facilitate an improved smile.

The first step in the treatment plan was to determine the proper position of the teeth in the face. Based on repose photographs, the incisal edge of tooth No. 8 was determined to be in the correct position and was used as the landmark to determine the maxillary edge position (Figure 5). This allowed for 0 mm of display of tooth No. 6.⁶ The rest of the maxillary occlusal plane was leveled using a facebow (Kois Dento-Facial Analyzer, Kois Center, koiscenter.com) to create an incisal plane parallel to the horizon. All of the other maxillary teeth, therefore, would need to be lengthened; thus, full occlusal coverage restorations were planned for the maxillary teeth. These restorations would be primarily additive ones due to the existing tooth structure loss from erosion and attrition. The mandibular teeth were in the correct position esthetically and required no alteration in length. The VDO would be opened to accommodate the added length planned for the maxillary teeth.⁷ A Kois deprogrammer would be used to locate a reproducible centric relation (CR) position to predictably open the bite.⁸

Due to the hopeless prognosis of tooth No. 8, it was planned for extraction. After discussing replacement options for tooth No. 8 with the patient, he opted for a fixed zirconia bridge instead of an implant. Because his moderate lip dynamics did not reveal structures apical to the central incisor gingival margin, it was determined that the fixed bridge could achieve a sufficiently esthetic outcome. The patient understood this and agreed to the plan before the initiation of treatment. Composite restorations were planned to seal the exposed dentin on the mandibular teeth and also to treat the caries on teeth Nos. 4 and 15. The patient had no desire to replace the missing teeth, Nos. 19 and 30. Implant restorations would be an option in the future if he decided to proceed with restoring those spaces.

Phase 1: Emergency Treatment

The patient was initially treated with endodontic therapy on tooth No. 8. This reduced his acute symptoms, and he was appointed for a comprehensive evaluation.

Phase 2: Disease Control

Scaling and root planing were completed first. The carious lesions were removed from teeth Nos. 4 and 15, which were then restored with direct composite resin restorations.

Phase 3: Kois Deprogrammer and Diagnostic Wax-up

A Kois deprogrammer was fabricated and delivered at the estimated VDO. After the patient wore it for 3 weeks, a repeatable CR position was located. A bite record and facebow were taken in this position. Stone models were then mounted in CR on a Panadent (Panadent, panadent.com) articulator. Because tooth No. 8 touched the platform (Figure 6), the rest of the maxillary teeth were waxed-up to match it. A putty matrix and temporary material were used to transfer the wax-up into the patient's mouth, which allowed him to directly see the proposed esthetic changes.

Phase 4: Transitional Bonding

Composite resin was used to establish the posterior occlusion at the new VDO. A new Kois deprogrammer was made at the wax-up VDO, and transitional composite was bonded onto the functional (palatal) cusps of maxillary teeth Nos. 3 through 5 and 12 through 14 (Figure 7). Shimstock was used to verify equal bilateral contacts. After the maxillary teeth were completed, mandibular composite restorations were placed on teeth Nos. 20 through 28, sealing all exposed dentin and restoring proper anatomy to the teeth. The occlusion was again equilibrated, and an anterior open bite from teeth Nos. 6 through 11 was created to allow space for restorative material.

Phase 5: Anterior Preparations, Extraction, and Temporization

The patient returned the next day for the preparation of teeth Nos. 6, 7, and 9 through 11. The teeth were prepared with minimal refinement on the palatal surfaces to create a definite margin (Figure 8). Tooth No. 8 was extracted and the socket curetted to remove granulation tissue. A collagen plug (CollaPlug, Zimmer Biomet, zimmerbiomet.com) was placed in the socket to help manage bleeding.

A six-unit provisional restoration was fabricated chairside using the wax-up matrix (Figure 9). An ovate pontic was placed, which extended 3 mm into the extraction socket of No. 8. Occlusion was verified with 8-µm foil (TrollFoil^™, TrollDental, trolldental.com) and with the patient sitting up and chewing on 200-µm blue articulating paper (Bausch, bauschpaper.com). Any blue marks left by the articulating paper, indicating possible chewing interferences, were removed from the teeth. A 3-month healing phase was planned for the extraction site.

Phase 6: Impression

During the healing phase no breakage or loosening of the provisional or composite restorations occurred, which confirmed a stable occlusion without any chewing interferences. There was some expected apical migration of the free gingival margin around the pontic, but it was not visible in the patient's Duchenne smile. An impression was taken of the working provisionals to help the dental laboratory duplicate the occlusion and incisal edge position in the definitive restorations. The provisionals were removed and a final impression and bite registration were taken. These were sent to the laboratory along with high-resolution photographs for fabrication of the restorations.

Phase 7: Cementation

The patient returned for try-in and cementation of the final layered zirconia restorations. The restorations were evaluated for proper marginal fit, correct occlusion, and esthetics. They were then cemented with a self-adhesive resin cement (RelyX^™ Unicem 2, 3M Oral Care, 3m.com) (Figure 10). The transitional posterior composite restorations were intact and would be functionally stable for the foreseeable future.

Phase 8: Definitive Posterior Restorations

Two months later, the patient returned for his periodontal maintenance appointment. The occlusion continued to be stable, and the patient was very happy with the esthetic result. He elected to proceed with definitive posterior restorations. Teeth Nos. 4, 5, 12, and 13 were prepared for full-coverage zirconia restorations. A bite record was taken in maximum intercuspation (MIP). When the patient returned for final cementation, the composite resin restorations were left in place on teeth Nos. 3 and 14. If in the future the patient were to elect to proceed with implants to replace missing teeth Nos. 19 and 30, full-coverage restorations for teeth Nos. 3 and 14 were recommended to him. The patient was very happy with the final esthetic results (Figure 11 through Figure 13).

The predictable esthetic and functional outcomes of this case began with both a comprehensive clinical examination and an understanding of the patient's needs and dental history. A systematic approach to treatment planning allowed this complicated case to be segmented into smaller phases for the patient's benefit. Patients often cannot afford ideal treatment, and this approach can provide them with treatment that can be better managed financially and logistically. The patient's esthetic objectives were achieved, while the biomechanical risk was decreased and the prognoses improved.

The patient recently returned to the clinic for a 4-year follow-up appointment (Figure 14). It was observed that the functional and esthetic outcomes were holding up very well without further treatment, demonstrating that risk in all categories had been reduced.

Sometimes it takes an emergency for patients to move forward with a comprehensive treatment plan that will address their dental problems and improve their oral health. The patient in this case had long been concerned about the wear and color of his teeth, but it wasn't until he experienced pain in tooth No. 8 and listened to the clinician's suggestion to receive a comprehensive examination that he finally accepted the care he needed. The diagnostic protocols presented in this article provided the clinician a systematic means of determining the patient's risks and how best to lower those risks. The Kois deprogrammer played a key role in opening the patient's bite in a predictable way. The patient now enjoys a brighter smile and can chew with confidence.

The author thanks Richard P. Washut, DDS, and Richard G. Washut, DDS, for all of their support; Howard Mizuta, DDS, for his mentorship and introducing to the author a higher standard of clinical dentistry; and the Kois Center Editorial Board for help in completing this article.

Kyle Washut, DDS
Private Practice, Selah, Washington; Head Dentist, Yakima Union Gospel Mission, Yakima, Washington