Color has been scientifically investigated by linking color appearance to colorimetric measurements of the light that enters the eye. However, the main purpose of color perception is not to determine the properties of incident light, but to aid the visual perception of objects and materials in our environment.
The decision of the right color of a restoration is always a critical step in restorative and prosthetic dentistry, as the final result of the manufactured fabricated by the dental technician. It mostly depends on the preliminary evaluation of the shade matching the remaining dentition. The wrong shade selection is the second most frequent reason for the failure and consequent repetition in the fabrication of indirect restorations. The dental technician who produces the prosthesis usually does not directly see the patient and often relies on the written prescription of the clinician which is based on the available shade guides. Thus, the final aesthetic result of the restoration is mutually dependent on the two operators, the dentist and the dental technician.
The shade selection can be instrumental or visual; the first one is objective, quantifiable and time saving. However, instruments for shade classification are basically designed for flat surfaces, so the reliability of shade matching on curved surface of tooth is questionable. On the other hand, the visual approach depends on a series of visual scales and physical and psychological interacting factors, such as stimulation, sensation, and perception of the observer that become critical point and could cause possible individual variation in the perception of the color. Factors such as age, gender, and clinical experience of the dental professional along with fatigue, emotions, lighting conditions, metamerism, type of shade guide, material used for the fabrication of prosthesis etc. are known to influence shade selection.
A study conducted by Aswini et al., from Amrita School of Dentistry, evaluated the effect of gender and clinical experience on shade perception by dental professionals. The cross-sectional study was performed in a dental school in India during the period of June 2017 to February 2018.
A total of 100 dental professionals with normal color vision who were categorized as dental students, dental doctors and dental specialists were included in the protocol. The study consisted on the identification of masked shade tabs to that of a complete set of shade guide.
Two shade guides tabs (VITA PAN Classical shade guide, VITA—Zahnfabrik, Germany) were used in the study. A2 and B2 shades tabs from the first shade guide were chosen. The identification mark on the shade tabs were masked with black adhesive tapes and labeled X and Y. The masked X and Y shade tabs were given to the participants and were asked to match the given shade to a complete set of shade guide.
The authors concluded that shade matching is critical in prosthetic and esthetic dentistry but, there is no significant effect of the gender and clinical experience on shade selection. Therefore, proper shade matching isn’t an individual decision but a confluence of multiple opinions and considerations.
(Photocredit: Dr. Allegra Comba)
For additional information: The effect of gender and clinical experience on shade perception
Oral surgery 04 December 2019
Prosthodontics 30 July 2019
Restorative dentistry 03 July 2019
Periodontology 15 January 2020
Oral Hygiene & Prevention 15 January 2020