The following article was published in the October 2019 edition of the Australasian Dentist Magazine and also Dentistry.co.uk.
When a patient presents with a tooth that requires a full cuspal coverage restoration, we as clinicians, are traditionally faced with two options of contrasting time and cost – a direct or indirect restoration.
A direct restoration, a ‘filling’, is made of a material such as resin composite or amalgam. An indirect restoration, a ‘crown’ or ‘onlay’ for instance, is made of a material such as porcelain or metal. Dentistry has continued to evolve in technology and materials over the years and we now have more products and treatment options available to us as clinicians, which we can discuss with patients. One Visit Crown (OVC) is an example, providing an innovative, alternate method to tackle full coverage restorations at a lower cost than a traditional crown and completed in a single dental visit.
The treatment option conundrum
The main considerations between the two traditional treatment options mentioned above is that they differ in the chairside time required to complete the restoration and financial cost to the patient.
A direct restoration is relatively quick and well-known to patients as a restorative choice, and is rather economical and effective for a finite period of time. On the other hand, an indirect restoration usually takes a dentist longer to complete chair side. It is done either over two separate appointments if done traditionally via a dental laboratory, or a single visit if done via CAD/CAM technology (eg CEREC). Although the latter reduces the procedure to just a single visit, both indirect options are typically priced significantly higher than a direct restoration.
‘Gold-standard’ for full cuspal coverage restorations is the indirect option. However, the challenge we face as dental clinicians is that some, due to the increased time taken or higher treatment fee, may find it a more difficult treatment option to communicate to patients and convince them to accept treatment.
A patient’s perspective
From the patient’s perspective, a lack of time and the financial cost, are the two main reasons Australians avoid or delay their dental visits (Australian Research Centre for Population Oral Health, 2012). The OVC addresses these two factors, allowing the clinician to offer a treatment option completed in a single visit and generally at a lower cost than a traditional indirect restoration.
The OVC consists of a unique 73% zirconia-filled hybrid ceramic material, in both the top, heat-cured layer, as well as the underlying uncured layer, providing a customised, lab-derived overlay option. Treatment is carried out in one appointment, saving valuable chairside time for the operator in comparison to a traditional indirect technique, thus improving both profitability for the clinician, but also a better experience for the patient as they do not have to return for a second visit.
One Visit Crown (OVC) clinical case study
The following case study is of a LR5, exhibiting signs of cracked tooth syndrome (CTS).
Figure 1
Figure 2
Figure 3
Figures 1, 2 and 3 show the initial presentation of the LR5, with a large existing distal occlusal composite restoration.
Four treatment options offered to the patient:
- No treatment (not advised)
- A conventional indirect restoration (ie crown or onlay)
- One Visit Crown (OVC)
- Direct resin composite restoration.
Treatment
After a discussion about treatment, the patient declined a conventional indirect restoration due to cost but did not want ‘just another filling done’ with a direct resin composite restoration. The patient decided instead to go ahead with the OVC.
This case was treated using a customised, lab-made OVC following a PVS bite registration impression taken during the patient’s initial examination appointment. It took a single 30-minute appointment to carry out the entire crown procedure.
The existing restoration was completely removed. After assessing the prognosis and restorability of the tooth, it was prepared minimally to receive the OVC. Once occlusion was reduced, a slight bevel was placed in the enamel, both buccally and lingually (Figure 4).
When significant tooth structure remains, the benefit of an OVC procedure over a traditional crown preparation with circumferential reduction of the tooth, is that the OVC procedure recommends minimal reduction to prepare the tooth for an adhesive onlay-type restoration.
Minimal tooth reduction when preparing for restorations has been shown to be better for the pulp (Ruiz, 2017). The compression dome concept after preparing a tooth in this manner has been shown to provide a strong coronal structure. It forms a ‘stable peripheral bond in conjunction with a compressive design’ (Milicich, 2017).
Final result
The OVC roughly in situ shown in Figure 5 – then correctly seated and adapted to the preparation using an occlusal seating guide fabricated and supplied by the lab (Figure 6).
Figure 5
This fabricated guide, unique to each patient, seats the crown onto the tooth preparation and into its ideal position. The advent of the customised OVC and seating guide removes the guesswork in crown placement, seating and occlusion. This also decreases the amount of finishing and polishing required.
Once seated, the uncured portion of the OVC wass light-cured and again after the band is removed (Figure 7).
Figures 8 and 9 show the crown finished and polished to give final results.
Figure 8
Figure 9
The One Visit Crown (OVC) offers a great alternate treatment option to restore teeth that require full cuspal coverage. Addressing the two main reasons patients avoid dental treatment, it may also help the clinician with patient communication and case acceptance. With a conservative preparation used wherever possible, the One Visit Crown is able to offer the clinician a healthy, strong and aesthetic restorative solution for posterior teeth where full cuspal coverage is indicated.
References
Australian Research Centre for Population Oral Health (2012) The avoidance and delaying of dental visits in Australia Australian Dental Journal 57(2): 243-7
Milicich G (2017) The Compression Dome Concept – The Restorative Implications. Gen Dent 65(5): 55-60
Ruiz JL (2017) Supra-Gingival Minimally Invasive Dentistry: A Healthier Approach to Esthetic Restorations. New York, New York: Wiley-Blackwell
About the author
Dr Sam Koh is a Melbourne-based dentist, graduating from The University of Melbourne with First Class Honours. As the principal dentist of Orions Dental Taylors Lakes, his special interests are in Cosmetic Dentistry and Orthodontics. Dr Koh has been awarded with prestigious fellowships from the International Academy of DentoFacial Esthetics in New York, the Pierre Fauchard Academy in London, as well as a fellowship in Orthodontics. He is the co-founder of the Young Dentist Hub, and a KOL for the One Visit Crown as well as several other dental companies.