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Fundamentals of Esthetic Implant Dentistry
shade progression allows for a natural look that does not obscure the vision. Shade relates to lip size and gender, as well. When restoring a young patient with a thick lip, lighter shades might be considered. On the contrary, when restoring an older patient, darker shades that are lower in value and higher in chroma than those seen in younger adults could be used. The dentine begins to dominate the shade to simulate the natural effect of worn enamel. Some stains can be added to emphasize oral habits such as smoking or tooth up-fractions, because it is illogical to give an 80-year-old patient lighter teeth that do not match his facial characteristics or complexion at this particular age. This could make a natural-looking person look artificial. The perception of the teeth shade is influenced by the tooth’s shape and its morphologic position within the arch, as well as the clinician’s decision (Golub-Evans 1994). (See Figure 3.30.)
Figure 3.29.
Natural shade progression.
Figure 3.30. An implant-supported prosthesis that lacks teeth characterization and lacks shade progression.
Factors Influencing Shade Selection Many factors influence artificial teeth shade selection: 1. Patient’s personality: Lighter shades usually are recommended because they add a positive impact to someone’s personality. 2. Facial features: Strong facial features such as wide eyes, a large nose, and prominent chin require lighter shades to match those features, as shown in Figure 3.31. 3. Skin color: A perception among clinicians has been that individuals with darker skin colors should have lighter shades of teeth. This perception is commonly explained by the greater contrast between skin color and tooth shade. Studies related to staining and altering tooth shades are abundant in the dental literature. Ahangiri and others (2002) explored the possibility of a relationship between tooth shade and skin color in a study of 119 individuals aged 18 to 80 years. Two investigators trained to examine tooth shade performed all of the examinations. A Vita-Lumin shade guide was used to examine either the maxillary right or left central incisor, one of which had to be restoration- and caries-free for study inclusion. Tooth shades were divided into four categories according to value. Skin tones were also divided into four categories (fair, fair/medium, medium, and dark) with the use of L’Oreal True Illusion compact makeup shades as a guide. Categorical modeling with chi-square analysis and Fisher’s exact tests was used to analyze the data. The study did not find any interaction among age, skin color, and tooth shade or gender, skin color, and tooth shade; however, age was associated with tooth shade. Older people were more likely to have teeth with lower values (darker). Among those aged 60 and older, 85% had teeth in the medium and low range values compared with 17%
Figure 3.31.
Strong facial features like prominent chin, wide black eyes.