A Conservative Treatment to Address Functional and Esthetic Concerns

This case report presents a patient concerned primarily with her smile. Some critical risks were not evident during examination and were only elicited by questioning the patient. These risks included the patient reporting that she had to squeeze her jaws together tightly to contact her back teeth, and some joint sounds were present as well. Had these key diagnostic factors been missed, her functional issues may have been overlooked and the esthetic outcomes eventually compromised.

Clinical Case Overview

A 20-year-old woman presented with chief concerns about the appearance of her teeth. She was unhappy with the size, shape, color, and position of the teeth as well as excessive gingival display (Figure 1 and Figure 2). The patient also reported that she needed to shift her jaw back to make her posterior teeth contact. She had never received orthodontic treatment, and her teeth had always appeared small.

After a dentist/patient discussion, the aim of treatment was to provide a balanced, functional occlusion while meeting the patient's desired esthetic outcome. The patient was diagnosed as having low periodontal and moderate biomechanical risks. Her dentofacial and functional risks were significant and would be considerable pitfalls if not managed properly. Due to a hypermobile maxillary lip, her teeth and gingiva were broadly displayed, and any restorative treatment would be highly visible. Further, if the functional issue that required her to shift her mandible posteriorly was not alleviated, any esthetic or restorative treatment of the maxillary anterior teeth would be in jeopardy. The teeth would need to be moved into acceptable positions for optimal chewing function and predictable restorative treatment. Orthodontic movement was ideal for these needs. Treatment would be sequenced to manage risk for each step, and the patient approved the plan.

Medical and Dental History

The patient's medical history was unremarkable and revealed no significant concerns that would affect her dental treatment. She had a history of asthma exacerbated by exercise and seasonal allergies that required the use of an albuterol inhaler less than once per week. She was determined to be American Society of Anesthesiologists (ASA) II classification.

Her dental history was more significant. Periodontally, the patient reported some localized bleeding when flossing her mandibular teeth. Biomechanically, she had some thermal sensitivity around her mandibular anterior teeth. She was also aware of a hole on a lower left molar. Functionally, she noted that when closing her teeth together, she had to shift posteriorly and squeeze her jaw for her molars to make full contact. She also noted that over the previous 5 years, her mandibular anterior teeth were becoming more crowded and there were some joint sounds on the left side. She was aware that she would occasionally clench throughout the day.

Diagnosis, Risk Assessment, and Prognosis

Periodontal: There were generalized 4 mm pockets with bleeding on probing. There was no bone loss present on the radiographs. Therefore, the patient was determined to be American Academy of Periodontology (AAP) stage I, grade B (Figure 3).¹

Risk: Low

Prognosis: Good

Biomechanical: Tooth No. 19 had pit-and-fissure caries and was given a hopeless prognosis without treatment. There were questionable restorations on teeth Nos. 3, 4, 13, and 14, giving them a fair prognosis without treatment.

Risk: Moderate

Prognosis: Hopeless

Functional: The functional examination showed normal range of motion. She had reported joint sounds on the left side, but the sounds could not be recreated during examination. There was no tenderness or discomfort in the head or neck muscles during examination, but she said sometimes there was soreness during the day from squeezing her jaw to make her teeth fit together. Load and immobilization tests had negative results. Minimal attrition (less than 1 mm) was present on teeth Nos. 6, 8, 9, 11, 24, and 25 (Figure 4). There was no fremitus present or mobility of any teeth. These findings, combined with her dental history, called for a diagnosis of constricted chewing pattern (CCP).^2.3 The diagnosis was primarily derived from patient reporting, and the clinician expected that the Kois deprogrammer (KDP) (Kois Center, koiscenter.com),⁴ which would be used in treatment, would confirm the diagnosis.

Risk: Moderate

Prognosis: Fair

Dentofacial: The patient's primary concern dentofacially was the small size of her teeth. This had been a longtime concern for her, as she could not remember a time when they were longer or bigger. She wanted a smile that appeared more like that of an adult. Teeth Nos. 8 and 9 were each 7.1 mm long and 6.9 mm wide, which confirmed her perception of undersized teeth. The normal size of a central incisor for a patient with an inter-alar width of 37.8 mm is 10 mm long and 8.5 mm wide.⁵ Esthetic evaluation revealed that her upper lip was hypermobile; the lip moved vertically 8.2 mm at the maxillary cuspids and 11.2 mm at the maxillary central incisors. Full display of maxillary anterior teeth along with more than 2 mm of gingiva in the Duchenne smile meant that any esthetic dental treatment would be highly visible and, therefore, high risk (Figure 5).

Risk: High

Prognosis: Poor

Treatment Goals

The treatment goals were centered around creating long-term success in addressing her primary concerns. This included reducing the patient's periodontal risk, alleviating her functional and biomechanical concerns, and maximizing the chances for the desired esthetic (dentofacial) outcome. To accomplish the dentofacial and functional goals, treatment of the CCP was necessary. The chewing pathway would need to be opened, and equal, simultaneous, bilateral, posterior contacts would be created. This would allow the patient to close on her back teeth without shifting and squeezing her jaw and, thus, decrease her self-reported symptoms of muscle soreness and tenderness. It would also create needed restorative space to improve the size and shape of teeth Nos. 6 through 11. The increased space would allow for additive dentistry, less tooth preparation, and conservative use of restorative materials to decrease biomechanical risk.

Treatment Plan

Diagnostic records were taken, including intraoral and extraoral photographs, radiographs, a cone-beam computed tomography (CBCT) scan, and an intraoral scan (iTero Element^® 5D, Align Technology, Inc., itero.com) in maximum intercuspation (MIP) and with a leaf gauge. The patient's periodontal needs would be treated with routine scaling and recommendations for proper home hygiene and ongoing routine scaling. Her biomechanical needs would be resolved with a composite restoration. A KDP would be fabricated and used to establish centric relation (CR) to confirm the expected CCP diagnosis and achieve predictable functional results.

The patient's esthetic concerns would be addressed by proper orthodontic alignment, additive equilibration, and proper positioning of the teeth relative to her face. Direct and indirect restorations would be utilized to complete the desired esthetic outcome.

Phase 1: Periodontal Treatment, Caries Control, and Deprogramming

The patient received routine scaling and oral hygiene instructions. Oral hygiene was improved and the inflammation was eliminated over the course of 4 months before proceeding with orthodontic and restorative therapies. She was placed on a 6-month recare frequency. The occlusal carious lesion on tooth No. 19 was removed and restored with a direct composite restoration.

The patient wore the KDP for 3 weeks. She reported that when she removed the deprogrammer, the first point of closure contact was consistently teeth Nos. 25 and 26 against tooth No. 7. Occlusal registration records were taken that confirmed the patient's occlusal report as well as the diagnosis of CCP.

Phase 2: Orthodontic Planning and Smile Design

For orthodontic planning purposes, the facial gingival margin of tooth No. 6 was used as a reference to plan the ideal position of the maxillary anterior teeth and gingival margins. The maxillary incisor gingival margins were intruded 1 mm to match the facial height of the gingival margins of the cuspids. The lateral incisor gingival margins would be positioned approximately 0.5 mm coronal to the central incisors and cuspids. Diastemas were left in the anterior six teeth to allow for less tooth reduction.

Proclination and intrusion of the maxillary teeth were critical to removing the constricted pathway and improving the gummy smile. Intrusion created less need for incisal reduction during the restorative phase. Teeth Nos. 24 and 25 were intruded 1 mm, which also helped open the functional chewing pathway.

The anticipated final stage was exported from Invisalign^® (Align Technology, Inc., invisalign.com) and imported into exocad software (DentalCAD Smile Creator module) (exocad, exocad.com) to allow for pretreatment planning. Indirect restorations were planned for teeth Nos. 7 through 10, and direct restorations were planned in exocad (Figure 6) for teeth Nos. 6 and 11 because only minor cusp tip additions were needed. This planning allowed for adjustments of the Invisalign ClinCheck visualization tool to minimize enamel reduction.

Phase 3: Clear Aligner Orthodontics, Equilibration, and Frenectomy

Orthodontic treatment was initiated with clear aligners (Invisalign). The intraoral scanner was used to capture the records. The KDP CR reference position was used in the mouth when obtaining the interocclusal records. During the 8-month orthodontic treatment time, regular progress checks were used to verify that the tooth movement was consistent with the planned outcomes of the case. This included incisal edge position, gingival level location, prescribed intrusion, buccal corridor expansion, and desired overbite and overjet.

After orthodontic treatment, another KDP was fabricated to confirm that the patient no longer had a CCP. Her mandible had moved forward to a comfortable position, and she no longer had to shift or squeeze to contact her posterior teeth. The patient confirmed that she no longer clenched or had any joint sounds or symptoms. Additive equilibration (using direct application of composite resin) was performed as needed on the mandibular posterior teeth to create bilateral, equal-intensity, simultaneous contacts (Figure 7).

A maxillary labial frenectomy was also performed at the time of completion of orthodontic movement with an erbium, chromium: yttrium, scandium, gallium garnet (Er,Cr:YSGG) laser (Waterlase Express, Biolase, biolase.com). This treatment was added because teeth Nos. 7 through 10 had been intruded and the pre-existing diastemas between teeth Nos. 6 through 11 narrowed more than what was initially planned for. The elimination of the thick sulcus attachment of the frenum fibers was intended to help stabilize the orthodontic treatment.⁶

Phase 4: Post-orthodontic Treatment Planning

After the completion of orthodontic treatment, a new KDP was worn by the patient, occlusal records were taken to verify MIP coincidence with CR, and new photographs and digital scans were taken. The smile design that was completed initially was confirmed and adjusted as needed in the software (exocad) and the cast was printed at 50 microns for accuracy using a 3D printer (Einstein^™, Desktop Health, health.desktopmetal.com) and model resin (Model X, Desktop Health). A putty matrix (Ivoclar Virtual^® XD Putty, Ivoclar, ivoclar.com) was fabricated on the printed model and trimmed.

Phase 5: Definitive Maxillary Restorations

To avoid imprecise shade selection due to enamel dehydration during the appointment, shade selection was made prior to the procedure. Shades were taken using four different techniques for effective communication with the laboratory ceramist. The first used multiple VITA 3D shade tabs (VITA North America, vitanorthamerica.com), the second used the 3D shade tabs with monochromatic picture mode (Figure 8), and the third used the 3D shade tabs with polarized light (Figure 9). The fourth technique utilized the eLAB card (eLAB, elabprime.com), a method that focuses on the teeth adjacent to those being restored (Figure 10).

A try-in of the proposed restorative treatment was done with bisphenol A-glycidyl methacrylate (bis-GMA) resin in a putty matrix. The patient accepted the proposed esthetic outcome. The provisional restorations were not removed, and anesthesia was provided for teeth Nos. 7 through 10 for patient comfort.

The incisors were reduced through the provisional restorations using diamond reduction burs for minimal preparation of the tooth structure within enamel (Figure 11). The interproximal preparations were placed below the gingival margins to allow the ceramist the space to create ideal embrasures and emergence profiles when closing the diastemas. Preparations were polished with a white stone (Arkansas abrasive white stone, fine grit, Brasseler USA, brasselerusa.com) and sharp angles were rounded with a coarse finishing and polishing disc (Clinician's Choice, clinicianschoice.com). Provisional restorations were reapplied to the preparations to check for even and adequate reduction. Depth burs were used a second time to remove the temporaries and confirm proper reduction was achieved for ideal ceramic thickness. Stump shades were determined using the IPS Natural Die Material Shade Guide (Ivoclar). After retraction cords were placed, maxillary and mandibular vinyl polysiloxane (Affinity^™, Clinician's Choice) impressions were taken as was a bite registration (Futar^®, Kettenbach Dental, kettenbach-dental.com) in MIP.

Final provisional restorations were fabricated from the putty matrix using an indirect technique where they were contoured and polished outside of the mouth and then spot bonded into place. Finally, a digital scan of the maxillary teeth was utilized to print a cast, and a provisional Essix retainer was produced to maintain the tooth position while the ceramics were fabricated.

When the patient returned for cementation, the provisional restorations were removed, and the veneers were tried in and approved by the patient and clinician. After anesthesia was administered, a heavy rubber dam (Nic Tone, Henry Schein Dental, henryschein.com) (Figure 12) was placed, and the teeth were cleaned with 27-µm aluminum oxide (PrepStart^™, Zest Dental Solutions, zestdent.com). Then the teeth were etched, rinsed, dried, and wetted with thinned adhesive bonding agent (Adhese Universal, Ivoclar). All intaglio surfaces of the crowns were etched, silanated, bonded in with adhesive cement (Variolink^® Esthetic LC neutral, Ivoclar), and light-cured.

Direct composite restorations (Evanesce^™, Clinician's Choice) were bonded on teeth Nos. 6 and 11 using a lingual matrix (Figure 13). The restorations were placed, cured, and polished with rubber wheels.

The occlusion was verified and adjusted with 8-µm articulating paper (TrollFoil, TrollDental USA, trolldental.com). Lateral excursions were marked with red articulating film (AccuFilm^®, Parkell, parkell.com), and marks on inclined planes were removed. The patient then sat upright and chewed on 200-µm paper to verify proper occlusion with no interferences in the envelope of function.^7,8 Final orthodontic records were taken, and final retention appliances were fabricated and delivered to the patient.

Final post-treatment photographs are shown in Figure 14 through Figure 17.

Discussion

When the patient first presented with esthetic concerns, it was necessary for the clinician to clearly understand what these concerns meant to her and whether she wanted to have a previous smile restored or a new smile created. Once the patient's desired outcome was understood, a systematic examination was used to properly assess her risks. The risks were addressed and managed to enhance long-term success of restorations, function, patient comfort, and esthetics. The patient was willing to complete the treatment as presented, and she followed post-treatment recommendations.

One year after completion, no complications have been noted and the esthetics remain excellent. Resolution of the CCP helped improve the patient's functional risk to "low" and her prognosis to "good." Her dentofacial risk remains unchanged due to her high lip dynamics; however, her prognosis improved to "good" because her esthetic concerns were addressed. Her biomechanical prognosis improved due to the caries removal; however, the risk remained the same because of the addition of anterior ceramic restorations.

Conclusion

After complete diagnosis, use of the KDP, orthodontics, and additive restorative dentistry, proper occlusal function was achieved to support the excellent esthetic result. The CCP was eliminated, gingival levels were aligned, and the shape and color of teeth were enhanced, thus facilitating a beautiful and functional smile. An additional benefit of this treatment was the elimination of the patient's clenching, further improving her quality of life.

Acknowledgment

The author thanks Juan J. Rego, CDT, FAACD, and Nelson A. Rego, CDT, AAACD, of Smile Designs by Rego for their laboratory support; Betsy Bakeman, DDS, for the diagnostic wax-up course; Diana Tadros, DDS, for the Exocad Elite course; and John Kois, DMD, MSD, for all of his support.

Disclosure

The author lectures on behalf of Desktop Health but did not receive any compensation or material support related to this patient's treatment or this article.

About the Author

Megan A. Shelton, DMD

Private Practice and Practice Consultant, Carlsbad, California