PROSTHODONTICS 1 (DENTISTRY) The color wheel shows the relationships of
FUNDAMENTALS OF ESTHETICS primary, secondary, and complementary
hues
A. Perfect smile Primary Hues
a) Skill • Red
b) Art • Yellow
c) Perception • Blue
B. Color theory Secondary Hues
By Isaac Newton The blend of any two primary hues will form
First to refract light a secondary hue.
Light as a wave Altering the chroma of the primary hues in a
Light wavelength mixture will alter the hue of the secondary
It is the interaction of light with an object makes the hue produced.
color perception possible Primary and secondary hues are organized
C. Physics of light on the color wheel with secondary hues
a) Emission - the source of light; this can be produced positioned between primary hues
physically or chemically Complementary Hues
b) Transmission - occurs when light passes through a Colors directly opposite each other on the
translucent or transparent object color wheel are termed complementary hues
c) Reflection - when light strikes a solid object and bounces Primary hue + complementary secondary
off of it hue = gray.
d) Absorption - a process where light is absorbed by an When a portion of a crown is too yellow,
object lightly washing with violet (the
e) Perception - occurs in the brain, rods perceive brightness complementary hue of yellow) produces
and cones perceive hue (color) an area that is no longer yellow.
D. Light and shadow The yellow color is canceled out and the area
a) Light is necessary todiscern things. Most objects occur in will have an increased grayness (a lower
2D value).
b) True natural light - multidirectional Complementary hues is also used for
c) It shows texture quality and throws shadow intensification
d) This property adds dimension of depth Place 2 complementary hues next to one
e) Shadow created by depth conveys shape another, they are each intensified and
E. Principle of color appear to have a higher chroma.
1. Hue To change hue, lessen chroma, or lower
2. Chorma value, place the complementary hue over the
3. Value color to be modified.
4. Color wheel Hue Sensitivity
5. Matermarism After 5 seconds of staring at a tooth or shade
6. Opacity and translucency guide, the human eye adapts and becomes biased.
7. Depth If an individual stares at any color for longer than
8. Fluorescence and opalescence 5 seconds and then stares at a white surface or
a) Hue closes his or her eyes, the image appears, but in
• Hue is the name of the color. the complementary hue.
• Young permanent dentition: consistent throughout the This is known as hue sensitivity and it negatively
mouth. affects shade selection.
• With aging, variations in hue occur because of intrinsic After 5 seconds, look away or stare briefly at a blue
and extrinsic staining from restorative materials, foods, surface (such as a patient napkin). This will readapt
beverages, smoking, and other influences your vision to the orange-yellow portion of the
b) Chroma spectrum, the portion most involved in color
• Chroma is the saturation or intensity of hue matching.
• It can only be present with hue. e) Metamerism
• In general, the chroma of teeth increases with age Change of color matching of two objects under
c) Value different light sources.
• Value is the relative lightness or darkness of a color. There is more than one way to produce a color. It can
• A light tooth has a high value while a dark tooth has a either be pure, or a mixture of two other colors (e.g.,
low value. pure green versus a mix of blue and yellow).
• It is the quality of brightness on a gray scale. If both colors are exposed to a light with a full color
Value sequencing: spectrum, they will appear similar. However, if they are
B1 A1 B2 D2 A2 C1 C2 D4 A3 D3 B3 A3.5 B4 C3 A4 C4 exposed to a light source that does not contain light in
Value is the most important factor in shade selection the blue band, the two colors will not appear similar.
Clinical Relevance
Color relationship - Shade selection that works well under a variety of lights
d) Color wheel is preferred to a match
Hues have a relationship to one another that can Usually three sources of light are available in the dental
be demonstrated on a color wheel. operatory:
, 1. Outside daylight through a window The exact proportion of the distal tooth to the mesial tooth is
2. Incandescent lighting from the dental operatory lamp 0.618.
3. Cool white fluorescent lighting from overhead fixtures 2. Artistic biases and illusion
Clinical Application Artistic biases are inherent in the perception of form. The most
• Tip: Patients spend a great deal of time in one lighting important of these is the perception is the principle of
situation. This should be taken into consideration during illumination. The light areas appear to be positioned forward,
shade selection. whereas the darker areas appear to recede. This produces the
• Remember: The best approach to color matching is to illusion of a third dimension (depth).
use three light sources. Another artistic bias of that is important in esthetics is the use
f) Opacity and Translucency of horizontal and vertical lines. A horizontal line causes an
Light does not pass through opaque materials because object to appear wider, whereas a vertical line causes an object
it reflects all the light that is directed onto it. Translucent to appear longer. This can be termed the principle of line.
materials allow some light to pass through them. 3. Principles of line
Translucency provides realism to Horizontal lines (through cervical staining, texturing) produce
dental restorations because of the inherent the illusion of width while vertical lines (through narrowing the
translucent quality of enamel. face of the tooth, carving the incisal edges to slope cervically,
g) Depth deepening the incisal embrasures) produce the illusion of length.
Depth is the threedimensional concept of color.
Depth may be a problem if translucent composite is used
to restore preparations that extend completely from
facial to lingual surfaces. The
restoration may appear gray or overly translucent.
Change: add a more opaque composite resin on the
lingual portion of the restoration and then over it, a
translucent resin is placed. This will give a natural illusion
of depth results.
Shade Progression 4. Using the principles the perception of to control illusion
The maxillary anterior teeth and premolars are not The Law of the Face (of the Tooth)
uniform in shade. The law of the face is the most important single concept in
The lateral incisors are similar in hue to the central shaping dental restorations.
incisors but are slightly lower in value. This concept plays with the “light” and “dark “, which helps the
The canines are also lower in value than the dentist to shape all esthetic restorations correctly.
incisors but also exhibit greater chroma saturation. The face of a tooth is the area on the facial surface of anterior
The premolars have values similar to the lateral and posterior teeth, and it is bordered by the transitional line angles
incisors. as seen from the facial (labial) aspect
h) Fluorescence The law of the face states that to make dissimilar
Fluorescence happens when a material absorbs short teeth appear similar, the dentist should make the
wavelength light and reemits light of longer wavelength apparent faces equal. Creating equal apparent
Dentin is the primary source of fluorescence in human faces in two dissimilar adjacent teeth produces
teeth. dissimilar areas outside the transitional line angles (i.e., outside the
Fluorescence reduces chroma and raises value without faces).
changing translucency.
Fluorescent porcelains mimic dentin resulting in
brighter and more vital, life-like restorations.
i) Opalescence
Opalescence occurs when a material appears as one color
when light is reflected off its surface and a different color
when light is transmitted through it.
Opalescence mimics enamel and is highly wavelength
dependent.
Enamel scatters violet and blue light within its body.
The effect is that the incisal enamel to appear bluish and
Clinical application
translucen
Equal apparent faces can be most effectively created by
F. Principles of form
shaping the facial surface to reposition the transitional line
1. Golden proportion
angles. This creates an appropriate shadow.
The Golden proportion by Euclid states that for objects to be
If a transitional line angle cannot be repositioned on a
proportional to one another the ratio of 1:1.618 is esthetically
restoration, illumination can be used. A portion of the tooth
pleasing.
can be stained darker to create the illusion that the
A smile (viewed from the front) is considered to be esthetically
transitional line angle has been moved and that the portion of
pleasing if each tooth in that smile (starting from the midline) is
the tooth is receding. In cases like these, only the “apparent
approximately 60% of the size of the tooth immediately mesial
face” should be manipulated and not the actual face
to it.
FUNDAMENTALS OF ESTHETICS primary, secondary, and complementary
hues
A. Perfect smile Primary Hues
a) Skill • Red
b) Art • Yellow
c) Perception • Blue
B. Color theory Secondary Hues
By Isaac Newton The blend of any two primary hues will form
First to refract light a secondary hue.
Light as a wave Altering the chroma of the primary hues in a
Light wavelength mixture will alter the hue of the secondary
It is the interaction of light with an object makes the hue produced.
color perception possible Primary and secondary hues are organized
C. Physics of light on the color wheel with secondary hues
a) Emission - the source of light; this can be produced positioned between primary hues
physically or chemically Complementary Hues
b) Transmission - occurs when light passes through a Colors directly opposite each other on the
translucent or transparent object color wheel are termed complementary hues
c) Reflection - when light strikes a solid object and bounces Primary hue + complementary secondary
off of it hue = gray.
d) Absorption - a process where light is absorbed by an When a portion of a crown is too yellow,
object lightly washing with violet (the
e) Perception - occurs in the brain, rods perceive brightness complementary hue of yellow) produces
and cones perceive hue (color) an area that is no longer yellow.
D. Light and shadow The yellow color is canceled out and the area
a) Light is necessary todiscern things. Most objects occur in will have an increased grayness (a lower
2D value).
b) True natural light - multidirectional Complementary hues is also used for
c) It shows texture quality and throws shadow intensification
d) This property adds dimension of depth Place 2 complementary hues next to one
e) Shadow created by depth conveys shape another, they are each intensified and
E. Principle of color appear to have a higher chroma.
1. Hue To change hue, lessen chroma, or lower
2. Chorma value, place the complementary hue over the
3. Value color to be modified.
4. Color wheel Hue Sensitivity
5. Matermarism After 5 seconds of staring at a tooth or shade
6. Opacity and translucency guide, the human eye adapts and becomes biased.
7. Depth If an individual stares at any color for longer than
8. Fluorescence and opalescence 5 seconds and then stares at a white surface or
a) Hue closes his or her eyes, the image appears, but in
• Hue is the name of the color. the complementary hue.
• Young permanent dentition: consistent throughout the This is known as hue sensitivity and it negatively
mouth. affects shade selection.
• With aging, variations in hue occur because of intrinsic After 5 seconds, look away or stare briefly at a blue
and extrinsic staining from restorative materials, foods, surface (such as a patient napkin). This will readapt
beverages, smoking, and other influences your vision to the orange-yellow portion of the
b) Chroma spectrum, the portion most involved in color
• Chroma is the saturation or intensity of hue matching.
• It can only be present with hue. e) Metamerism
• In general, the chroma of teeth increases with age Change of color matching of two objects under
c) Value different light sources.
• Value is the relative lightness or darkness of a color. There is more than one way to produce a color. It can
• A light tooth has a high value while a dark tooth has a either be pure, or a mixture of two other colors (e.g.,
low value. pure green versus a mix of blue and yellow).
• It is the quality of brightness on a gray scale. If both colors are exposed to a light with a full color
Value sequencing: spectrum, they will appear similar. However, if they are
B1 A1 B2 D2 A2 C1 C2 D4 A3 D3 B3 A3.5 B4 C3 A4 C4 exposed to a light source that does not contain light in
Value is the most important factor in shade selection the blue band, the two colors will not appear similar.
Clinical Relevance
Color relationship - Shade selection that works well under a variety of lights
d) Color wheel is preferred to a match
Hues have a relationship to one another that can Usually three sources of light are available in the dental
be demonstrated on a color wheel. operatory:
, 1. Outside daylight through a window The exact proportion of the distal tooth to the mesial tooth is
2. Incandescent lighting from the dental operatory lamp 0.618.
3. Cool white fluorescent lighting from overhead fixtures 2. Artistic biases and illusion
Clinical Application Artistic biases are inherent in the perception of form. The most
• Tip: Patients spend a great deal of time in one lighting important of these is the perception is the principle of
situation. This should be taken into consideration during illumination. The light areas appear to be positioned forward,
shade selection. whereas the darker areas appear to recede. This produces the
• Remember: The best approach to color matching is to illusion of a third dimension (depth).
use three light sources. Another artistic bias of that is important in esthetics is the use
f) Opacity and Translucency of horizontal and vertical lines. A horizontal line causes an
Light does not pass through opaque materials because object to appear wider, whereas a vertical line causes an object
it reflects all the light that is directed onto it. Translucent to appear longer. This can be termed the principle of line.
materials allow some light to pass through them. 3. Principles of line
Translucency provides realism to Horizontal lines (through cervical staining, texturing) produce
dental restorations because of the inherent the illusion of width while vertical lines (through narrowing the
translucent quality of enamel. face of the tooth, carving the incisal edges to slope cervically,
g) Depth deepening the incisal embrasures) produce the illusion of length.
Depth is the threedimensional concept of color.
Depth may be a problem if translucent composite is used
to restore preparations that extend completely from
facial to lingual surfaces. The
restoration may appear gray or overly translucent.
Change: add a more opaque composite resin on the
lingual portion of the restoration and then over it, a
translucent resin is placed. This will give a natural illusion
of depth results.
Shade Progression 4. Using the principles the perception of to control illusion
The maxillary anterior teeth and premolars are not The Law of the Face (of the Tooth)
uniform in shade. The law of the face is the most important single concept in
The lateral incisors are similar in hue to the central shaping dental restorations.
incisors but are slightly lower in value. This concept plays with the “light” and “dark “, which helps the
The canines are also lower in value than the dentist to shape all esthetic restorations correctly.
incisors but also exhibit greater chroma saturation. The face of a tooth is the area on the facial surface of anterior
The premolars have values similar to the lateral and posterior teeth, and it is bordered by the transitional line angles
incisors. as seen from the facial (labial) aspect
h) Fluorescence The law of the face states that to make dissimilar
Fluorescence happens when a material absorbs short teeth appear similar, the dentist should make the
wavelength light and reemits light of longer wavelength apparent faces equal. Creating equal apparent
Dentin is the primary source of fluorescence in human faces in two dissimilar adjacent teeth produces
teeth. dissimilar areas outside the transitional line angles (i.e., outside the
Fluorescence reduces chroma and raises value without faces).
changing translucency.
Fluorescent porcelains mimic dentin resulting in
brighter and more vital, life-like restorations.
i) Opalescence
Opalescence occurs when a material appears as one color
when light is reflected off its surface and a different color
when light is transmitted through it.
Opalescence mimics enamel and is highly wavelength
dependent.
Enamel scatters violet and blue light within its body.
The effect is that the incisal enamel to appear bluish and
Clinical application
translucen
Equal apparent faces can be most effectively created by
F. Principles of form
shaping the facial surface to reposition the transitional line
1. Golden proportion
angles. This creates an appropriate shadow.
The Golden proportion by Euclid states that for objects to be
If a transitional line angle cannot be repositioned on a
proportional to one another the ratio of 1:1.618 is esthetically
restoration, illumination can be used. A portion of the tooth
pleasing.
can be stained darker to create the illusion that the
A smile (viewed from the front) is considered to be esthetically
transitional line angle has been moved and that the portion of
pleasing if each tooth in that smile (starting from the midline) is
the tooth is receding. In cases like these, only the “apparent
approximately 60% of the size of the tooth immediately mesial
face” should be manipulated and not the actual face
to it.
