October 2013, Volume 34, Issue 9
Published by AEGIS Communications
“Training Teeth”: Transitional Resin Bonding for Diagnostic Purposes
Despite the best diagnostic efforts, the etiology of a patient’s dental disease may remain elusive. Without knowing the underlying disease factors, predictable outcomes are difficult to obtain. This case report describes the diagnosis and treatment of a patient who felt embarrassed by the appearance of his smile and was desperately seeking a solution. Despite meticulous data collection and a systematic diagnostic approach, the disease etiology could not be determined. It was, therefore, decided to treat the patient with non-invasive transitional directly bonded composite to “road test” his new teeth. In this way, a determination could be made as to whether they would function successfully over time.
Proper diagnosis of a patient’s dental disease is vital to achieving a predictable outcome. In this case report, a 29-year-old yoga instructor visited the author’s dental office seeking treatment for acute pain on his lower right and to improve his smile (Figure 1 and Figure 2). He had not seen a dentist for the past 11 years, largely due to financial constraints.
The patient was embarrassed by the appearance of his smile and very much wanted a solution. Thorough data collection and a systematic diagnostic approach were used to try to determine the disease etiology, yet it remained elusive. Therefore, non-invasive transitional directly bonded composite was used to treat the patient to allow him to “road test” his new teeth, and thus ensure they would function successfully over time.1
Medical and Dental History
The patient’s medical history was unremarkable. As for dental history, the patient reported that he was treated with fixed orthodontic appliances 10 years prior. He reported that most of the damage to his front teeth occurred when his brackets were removed, and that the appearance of his front teeth had not changed in the past 10 years apart from minor chips, which he attributed to playing contact sports without a mouthguard. He felt uncomfortable when he smiled and expressed a strong desire to change the appearance of his teeth. He knew that he had several cavities but indicated no periodontal or functional problems.
Panoramic (Figure 3), bitewing, and cephalometric radiographs were taken. The cephalometric analysis revealed a Class I skeletal relationship with slightly increased vertical proportions, indicating a doliofacial growth pattern and retroclined lower incisors.
No abnormal findings were noted.
Caries, defective restorations, and erosion were noted (Figure 4 and Figure 5). The lengths and tissue profile of teeth Nos. 8 and 9 suggested wear with compensatory overeruption. Tooth No. 26 was dark, suggesting non-vitality. His first bicuspids had been extracted during orthodontic treatment. He presented with an Angle Class I molar relationship with the left first molars in cross-bite.
The examination revealed normal range of motion, no joint sounds, and negative load and immobilization tests. The anterior teeth held shimstock foil when the patient occluded in his habitual maximum intercuspal position (MIP), and fremitus was observed during light tapping of the teeth in this position. With the patient seated upright at 45 degrees, he chewed on 200µ thick articulating paper.2 No blue streaks were noted on the anterior teeth, indicating that he did not have a constricted envelope of function.
Diagnostic Findings, Risk Assessment, and Prognosis
Periodontal: The patient’s oral hygiene was fair, and he presented with slight tissue inflammation and minimal bone loss. Localized 4-mm pocket depths were noted around the upper molars and lower wisdom teeth. He was classified as an AAP type II patient.
Biomechanical: Teeth Nos. 17, 18, and 32 were carious, a defective restoration was noted on tooth No. 14, and questionable restorations were present on teeth Nos. 3 and 31. Irreversible pulpal pathology was noted on tooth No. 26. Erosion was present on the occlusal surfaces of teeth Nos. 3, 4, 14, 19, 20, 29, and 30 and the lingual surfaces of Nos. 6 through 12, with the buccal surfaces of Nos. 8 and 9 being most severely eroded. The patient was questioned about the origin of this erosion, and he denied symptoms of acid reflux or habitual intake of acidic foods or beverages.
Functional: Based on the patient’s questionnaire answers and the absence of acute symptoms, the patient would be considered to have acceptable function; however, it was deemed prudent to investigate further due to the clinical signs noted at the examination. The patient was fitted with a Kois deprogrammer, and after 2 weeks, deprogramming was confirmed. Bite records and a Kois LazrTrak (Kois Center, www.koiscenter.com) face bow record were taken and mounted using a Panadent articulator (Panadent, www.panadent.com). Analysis revealed that the patient’s bite position after deprogramming had not shifted from his MIP position, thereby confirming the diagnosis of acceptable function.
Although the cephalometric analysis had revealed a Class I skeletal relationship, the analyzing orthodontist opined that the patient had a Class III growth tendency and the Class I relationship was the result of a slight backward rotation of the mandible. As mandibular growth in males can continue into the early twenties,3 ongoing growth after the completion of his orthodontic treatment may have caused a constricted position that the patient had “worn through“ into an acceptable functional relationship. While this would explain the wear and compensatory overeruption of these teeth, no explanation for the erosion was found.
Dentofacial: The central incisors were much shorter than the cuspids. Tissue zeniths of the centrals and bicuspids were not harmonious, and tissue scallop was high (Figure 4). The teeth were darker than the patient desired. The non-vital No. 26 was very visible in the smile. The smile was narrow and the buccal corridors insufficient; this was more pronounced on the left side due to the cross-bite.
The patient exhibited high lip dynamics (Figure 6). Special efforts were made to observe a true full smile, as he guarded his smile to hide the appearance of his teeth. It is extremely important to assess lip mobility correctly, as once the patient’s smile is corrected, he or she often smiles freely for the first time and might show more gingival display than anticipated.4
The decay, erosion, and pulpal pathology would be treated. To avoid increasing the patient’s biomechanical risk, it was important to meet his esthetic needs with minimal removal of tooth structure.
A treatment plan consisting of orthodontic treatment to intrude and slightly procline the upper centrals paired with minimally prepared feldspathic veneers was presented. This was rejected by the patient due to cost and was also deemed risky by the practitioner, as it was unclear if the erosion and wear had an ongoing component.
It was, therefore, decided to carry out corrective tissue surgery on teeth Nos. 4 through 13, then place direct resin veneers with no tooth preparation. The lower teeth would be bleached. This plan would slightly lower the biomechanical risk, as some of the eroded surfaces on the centrals would be covered. Treating the decay and erosion on the back teeth with direct composite onlays, extraction of the carious wisdom teeth and endodontic treatment on No. 26 would also lower the overall biomechanical risk. The functional risk would be tested, and if verified as low, the patient would still have the option to switch to feldspathic veneers. Thin lithium-disilicate shell crowns would be the treatment of choice should the erosion on the lingual surfaces of teeth Nos. 6 through 11 continue.
Phase 1: Periodontal and Bleaching
The patient received scaling and root planing. The lower arch was bleached with a custom bleach tray. Tooth No. 26 would be internally bleached after root canal therapy was completed.
Phase 2: Biomechanical
Root canal therapy was successfully completed on tooth No. 26, and teeth Nos. 1, 17, and 32 were removed under intravenous (IV) sedation. Decay, failing restorations, and erosion on the posterior teeth were treated with direct composite restorations.
Phase 3: Functional
No treatment was required.
Phase 4: Dentofacial
Surgical crown lengthening was performed in one session. The facial tissues of teeth Nos. 4 through 13 were cut to ideal height with a double-sided fine surgical blade, then a flap was raised and the crestal bone recontoured with a bone chisel, as gingival levels can only be predictably altered if crestal bone levels are addressed.5
After a healing time of 3 months, the resin veneers were placed. An additive wax-up had been completed, incorporating the desired increased length and shapes of the anteriors and wider buccal corridors. Special attention was taken when lengthening the incisal edges so as to not interfere with the chewing envelope. Lingual and facial silicone putty indexes were fabricated.6
The resin veneers were placed in three appointments with initial placement on Nos. 7 through 10, and later in separate appointments for teeth Nos. 3, 4, and 6 and then 11, 15, and 16.
At the first appointment, teeth Nos. 7 through 10 were anesthetized, and 00 retraction cords were packed and the fit of the lingual and facial silicone matrices was checked. The lingual matrix was marked with a sharp probe at the existing incisal edge. A flame-shaped bur was used to roughen the enamel, and the area to be bonded was further prepared by air abrasion at low pressure. After etching and bonding, a microhybrid composite in a clear enamel shade was applied into the lingual matrix in a thin layer, drawn slightly over the previously marked line. The composite was thickened toward the facial–incisal line angle, to create a natural “halo” effect.6 The matrix was then adapted to the teeth, and the lingual shelf was briefly cured. Excess composite on the lingual surface of the tooth was removed before the lingual shelf was fully cured (Figure 7).
Next, an opaque dentin shade was layered onto the teeth and the lingual shelf and drawn out into mamelon shapes, with the aid of a #3 sable brush, and fully cured (Figure 8). A hybrid composite was used for the lingual shelf and dentin layer to provide wear resistance and strength for the restoration.7
Finally, a microfill composite layer was applied to full contour and cured (Figure 9). Using a microfill composite on the facial allowed for optimum polish.8 A matrix pull-through technique was used in the interproximal areas. Final curing was done after application of a glycerin gel to ensure a fully cured restoration surface.9 The same incremental layering technique was used on the cuspids, bicuspids, and first molars. Shaping and polishing was completed using a series of fine grit diamonds and discs. Aluminum oxide polishing paste with felt discs and points under light pressure produced an esthetic final luster.
Occlusion was carefully checked using the constriction test described above, and any streaks on the lingual aspects of Nos. 7 through 10 were removed with a fine football-shaped diamond.
Composite veneers are an excellent treatment alternative in cases where financial constraints limit other options. They can also be used for diagnostic purposes before more cost-intensive treatments.
These veneers have been life changing for the patient. He continues to function well 3 years after placement (Figure 14), with no further erosion or chipping of the restorations. Moreover, he still has the option to switch to porcelain restorations in the future.
ABOUT THE AUTHOR
Sandra Hulac, DDS
Private Practice, Hong Kong, China
1. Smith BG, Bartlett DW, Robb ND. The prevalence, etiology and management of tooth wear in the United Kingdom. J Prosthet Dent. 1997;78(4):367-372.
2. Bakeman EM, Kois JC. 10 steps in designing proper clearance for functional pathways. J Cosm Dent. 2012;28(3):56-62.
3. Heij DG, Opdebeeck H, van Steenberghe D, et al. Facial development, continuous tooth eruption, and mesial drift as compromising factors for implant placement. Int J Oral Maxillofac Implants. 2006;21(6):867-878.
4. Kois JC. Treatment planning I: diagnostically driven. January, 2008; Seattle, WA.
5. Kois JC. Altering gingival levels: the restorative connection part I: biologic variables. J Esthet Dent. 1994;6(1):3-7.
6. Fahl N. Composite artistry: mastering anterior restorations. Journal of Cosmetic Dentistry. 2010;26(3):56-68.
7. Hervás-García A, Martínez-Lozano MA, Cabanes-Vila J, et al. Composite resins. A review of the materials and clinical indications [in Spanish]. Med Oral Patol Oral Cir Bucal. 2006;11(2):E215-E220.
8. Lambrechts P, Vanherle G. Structural evidences of the microfilled composites. J Biomed Mater Res. 1983;17(2):249-260.
9. Park H, Lee I. Effects of glycerin on the surface hardness of composites after curing. J Korean Acad Conserv Dent. 2011;36(6):483-489.