Clinical Case Study: Comprehensive Aesthetic Rehabilitation with Porcelain Veneers Post-Orthodontics

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

This clinical case explores the use of porcelain veneers to achieve a natural and aesthetically pleasing smile for a patient dissatisfied with the shape and shade of her teeth, despite having undergone orthodontic treatment. The patient, who had previously undergone bleaching, specifically sought a result that was natural in appearance and had a strong aversion to the artificial, overly bright appearance that she has seen on social media and on reality television.

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

Patient Background

The patient, a mid 50-year-old female, presented with well-aligned teeth following orthodontic treatment and had a single porcelain veneer placed on the upper right central incisor. Despite this treatment, she was unhappy with the shape of here teeth and the shade of her teeth, which had a greyish tinge—a particularly challenging discoloration to treat with conventional bleaching methods. Her primary concern was achieving a natural-looking smile that enhanced her overall facial aesthetics without appearing "fake."

Challenges with Tooth Shade

The patient had previously attempted both take-home and in-office bleaching. On examination, the grey discolouration in her teeth was generalised and likely to be intrinsic in nature. A polarised photo makes it easier to visualise discolouration.  Intrinsic stains, such as those caused by tetracycline, are more challenging to bleach due to their location in the dentin layer, which is less accessible to bleaching agents (Joiner 2006). While conventional bleaching methods can often address yellow and brown stains effectively, grey discoloration may require restorative intervention for optimal aesthetic results (Magne 2003).

Smile Assessment and Aesthetic Planning

The patient had a general dislike to the shape and levels of her teeth. Patients often give a non-specific and vague description like this that can be difficult to decipher. It is important to go through a systematic smile assessment that can uncover the issues that are causing disharmony in the smile. Failure to do so can lead to unsuccessful aesthetic outcomes for the patient. The issues in this case that was causing aesthetic disharmony were:

1. Lack of Central Incisor Dominance: Lombardi (1973) highlighted that the most important feature in a smile is central incisor dominance. This refers to the aesthetic concept in dentistry where the maxillary central incisors play a dominant role in the overall appearance of a person's smile. This dominance is critical in achieving a balanced and harmonious smile design. The concept involves not only the size and shape of the central incisors but also their proportion relative to other teeth, their position in the arch, and how they relate to the facial features. In this case, the central incisors proportions were indeed longer than any other teeth, however, they were approximately the same width as the lateral incisors which diminished central incisor dominance.
2. Midline cant: The dental midline was found not be parallel to the facial midline. A study by Kokich (1999) found that laypeople generally start to notice dental midline discrepancies when the cant exceeds 2mm.
3. Canine Aesthetics. The canines were found to lack prominence. Canines are often referred to as the "cornerstones" of the dental arch. They are typically more prominent than lateral incisors but less so than central incisors. Their position can significantly influence the perception of the smile's width and symmetry. According to Spear and Kokich (2007), properly positioned canines enhance the curvature of the smile arc and contribute to the balance between the anterior and posterior teeth.

Treatment Planning and Execution

Given the patient's desire to improve the shape and shade of the teeth, porcelain veneers were chosen as the optimal restorative solution. Composite veneers were considered as an alternative. The treatment plan included:

1. Aesthetic Smile Design: A detailed smile design was created and presented to the patient using an intra-oral mock-up, allowing her to visualise the expected outcome and provide feedback before proceeding with the final restorations.
2. Conservative Veneer Preparation: Minimal preparation of the teeth was carried out to preserve as much natural tooth structure as possible. An intraoral scan was taken of the preparations. Note the deep grey discolouration that was seen in the lateral incisors.
3. Veneer Bonding: The lithium disilicate veneers were issued with a split dam isolation technique due to the presence of the fixed palatal retainer. A full adhesive bonding protocol was carried out using the total-etch technique, Kerr Optibond FL and Kerr NX3 light cure cement.

Outcome and Discussion

The final result was a smile that met the patient's aesthetic goals—natural-looking aesthetics that improved the shade and shape of her teeth. The decision was made to keep the fixed palatal retainer in place during treatment. Through careful treatment planning, it was felt that removal of the fixed palatal wire was unnecessary given the conservative nature of the veneer preparations would not require extension onto the palatal surfaces of the anterior teeth. A case can be made that the fixed palatal retainer could have been removed and the use of a removable retainer during the interim would have sufficiently prevented orthodontic relapse. Although we started restorative treatment over 6 months post orthodontic treatment, there is always a risk of orthodontic relapse occurring with possible provisional veneers fracturing and lack of patient compliance.

The use of a systematic approach that progressed from an aesthetic smile design, aesthetic mock up and testing provisional veneers provided the patient with reassurance of a predictable outcome.

Conclusion

This case highlights the importance of a comprehensive aesthetic assessment, patient-specific treatment planning, and the consideration timing of restorative treatment after orthodontic treatment. The careful consideration of smile design, preparation techniques, and material selection played a crucial role in achieving an aesthetic and natural-looking outcome for the patient.