Clinical Case Study: Replacing Existing Veneers in Coordination with Orthodontics and Alteration of Gingival Levels

By Dr Andrew See. Aesthetic Dentist and Educator, Founder of Dental Mastery Academy.

BDS Hons (Syd), FRACDS, MSc(Lond), PGDipDentImplantology, FCGDENT(UK), FICOI, MFDS RCSEng

A 40-year-old woman presented unhappy with the aesthetics of her existing smile and in particular wanting to replace her porcelain veneers on 11 and 21. She was displeased with their thick, bulky and unnatural appearance. Her medical history was unremarkable.  She previously had composite veneers for as a teenager which was then replaced by porcelain veneers that has been in situ for 13 years.

Read the full article below or download the article published in Australasian Dentist Magazine, May-June 2024 Edition.

Clinical Findings

The patient had an unremarkable extra-oral assessment with the exception of a tender left masseter consistent with grinding. Upon intra-oral examination, there was mild to moderate crowding of the of the upper and lower anterior teeth, a narrow arch form with an Angle Class I occlusion. The incisal edge thickness of both 11 and 21 was 3mm.

The gingival levels of the anterior teeth were not in an ideal arrangement with the level of 21 being 1.5mm more apical than 11 and the left and right showed asymmetry. The gingival margins of 13 and 23 were also more incisal when compared to the incisors. The veneer on 21 exhibited a different shade to her surrounding dentition.

Smile Analysis

The clinical findings highlighted several factors which were causing the aesthetic concerns of the patient. 

Analysis of her smile in relation to her facial features and lips showed that she had a very high smile line showing up to 8mm on a high smile. Her central incisors were very dominant with no canine dominance and large buccal corridors. This was partly due to the malocclusion and tapered upper arch form. However, this was further accentuated by the thick existing porcelain veneers on the central incisors. This gives the typical ‘bucky’ appearance that patients often dislike.

On a closer inspection, contributing factors were the monochromatic appearance of the existing veneers and the rotation of 12 further disrupted the harmony in her smile.

Treatment Options/Plan

After collaboration with the patient, it was agreed that simply replacing the existing veneers may not achieve all her aesthetic goals. A case could be made to replace the existing veneers with thinner veneers that had more internal characterisations to make them look more natural and in harmony with surrounding teeth. However, this would be suboptimal as it does not address the disharmony in her smile mentioned previously. It was also not possible to restoratively align tooth 12 without compromising tooth structure and pulpal integrity.

The initial phase of treatment involved full banding orthodontic treatment to expand the arch form, resolve the crowding and attempt to align the gingival levels. Since the veneers on 11 and 21 had a 3mm thick incisal edge, discussion was made with the patient and the orthodontist about reshaping both central incisors to an ideal shape prior to orthodontic treatment and then aligning them with the view to replace the veneers post orthodontic treatment.

It was also important to highlight to the patient that there would be a discrepancy of 1.5mm between the incisal edges of the two central incisors once the gingival levels have been aligned orthodontically. She was given the option to restore the incisal edge during treatment but as this was additional cost and it would serve only a short purpose prior to veneers, she declined.

Nearing the completion of the orthodontic treatment, it is critical to revisit smile analysis together with the patient and orthodontist. This will allow final finishing movements to be incorporated that may avoid additional surgery or restorative treatment. In this case, 13 and 12 gingival levels were found to be 1.5mm more incisal than the contralateral side whilst the incisal edge arrangement was ideal. Gingival analysis showed to the patient that balance would be achieved by altering the gingival level of 13 and 12.  This could be achieved orthodontically or surgically.

If the former option was elected, this would add to orthodontic treatment time, but more importantly, the ideal incisal edge levels would be disrupted. Additional restorative treatment would be required to align the incisal edge positions to create symmetry and improve occlusal guidance. 

If the latter option was chosen, this would require surgical intervention in the form of either a gingivectomy (removing gingival tissues alone) or aesthetic crown lengthening surgery (removing bone and gingival tissues). After critical examination of the dentogingival complex, we determined a gingivectomy procedure could be carried out. The patient favoured this option as it did not require any additional restorative treatment on the incisal edges. 

Orthodontic appliances were removed and a fixed palatal wire was placed by the orthodontist due to the high potential for relapse due during restorative treatment. The gingivectomy procedure was subsequently carried out using a soft tissue diode laser and healing was uneventful.

Restorative phase

After healing of the gingival tissues, the teeth were conservatively prepared according to the aesthetic mock up and a polyvinyl siloxane impression was taken ensuring clear and distinct margins. This is key for the ceramist to create precise fitting veneers. The preparations were provisionalised with 3M Protemp 4 with well-fitting margins and accessibility for oral hygiene. The nanofillers in Protemp 4 provides an excellent surface finish that is conducive for oral hygiene and aesthetics. A prerequisite for predictable bonding of veneers is gingival health.

The challenge of a 2 veneer or a single veneer case is undoubtably shade matching and characterisation. In larger 8-10 veneer cases there is relative freedom in this matter and hence is less demanding. Close collaboration with the ceramist and patient is recommended as shade matching can be a frustration and any discrepancies will result in remakes and wasted chair time for the clinician, ceramist and patient alike. When matching veneers with the existing dentition, it is  paramount to incorporate internal characteristics for natural looking porcelain veneer.

The definitive lithium disilicate veneers were tried in and approved by the patient using different 3M RelyX Veneer try in paste which matches identically with the matching RelyX Veneer cement.  The intaglio surface of the veneers was cleaned and prepared for bonding using hydrofluoric acid etch and silanated. The veneers were adhesively bonded with RelyX Veneer cement with rubber dam isolation and then finalised and finished satisfying aesthetics, occlusion and phonetics. An occlusal splint and removable retainer was subsequently issued.

Unique to this case was navigating the fixed palatal wire during bonding. Excess resin cement in this area would cause an uncleansable plaque trap which would be detrimental to long-term gingival health and possible future loss of papilla and formation of a black triangle. The absence of retention within 6 months post orthodontic treatment may result in relapse and movement of teeth during restorative treatment and a fixed palatal wire forgoes the reliance on the patient to wear a removable retainer.

Orthodontist: Dr Riaan Foot, Wavescape Orthodontics.

Dental technician: Riccardo Borgonovo, Smile Art Lab.

"I’m delighted with the results of my veneers and love my new smile."

- R O'Droma, Sydney Australia