Removable prostheses and aesthetics
Once teeth are extracted and disposed of, important information is lost for future replacement. The size, shape and surface detail provide data of the natural dentition. It has been advocated that dental practitioners wash extracted teeth, pack them discreetly in a suitable container and offer them to the patient to keep for reference informs Besford and Sutton, 2018.
Clinical implication: Ask patients to bring several photographs to the first appointment showing natural teeth. A photometric method is described for selecting front denture teeth:
a. Measure the distance between the patient’s pupils (PD). Line up the zero edge of a metal ruler with the right edge of the patient’s right iris. Then, read off the right edge of the left iris in mm. A PD of 65 ± is typical.
b. Scan the photograph. Enlarge the image on a screen. Use a ruler or digital capilers to measure the PD on the photography and the width of the upper two central incisors on the photograph.
True width = photographic width X true PD
Photographic PD
A typical result would be 17.6 for the central and lateral incisors. Divide this by two to give the width of a single central incisor.
c. Use a mould chart to locate central incisors of approximately the correct width.
Practical application: Patients may have dentures whose appearance they really liked and wish to have repeated. There may be a relative who has similar teeth. Dental radiographs taken before the front teeth were extracted may indicate size and shape. Women’s teeth are on average 2% smaller than men’s teeth. Regarding colour selection in the older patient, it is up to the clinician to mention that lighter teeth for an older patient as usually difficult to reconcile as natural.
Reference: Besford, J.N. and Sutton, A.F., 2018. Aesthetic possibilities in removable prosthodontics. Part 3: Photometric tooth selection, tooth setting, try-in, fitting, reviewing and trouble-shooting. British Dental Journal 224(7), p.491.