Shade Selection
-
Upload
drgaurav6891 -
Category
Documents
-
view
157 -
download
3
Transcript of Shade Selection
![Page 1: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/1.jpg)
k
GOOD AFTERNOON
![Page 2: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/2.jpg)
The Science of Color and Shade Selection
Presented by
Gaurav TripathiP.G. Student
Dept. of Prosthodontics
![Page 3: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/3.jpg)
The theory or philosophy of taste; the science of the beautiful in nature and art; especially that which treats of the expression and embodiment of beauty by art.[Websters].
Esthetics
![Page 4: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/4.jpg)
EstheticsIt is not absolute but extremely subjective
![Page 5: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/5.jpg)
![Page 6: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/6.jpg)
Earlier it was thought as
![Page 7: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/7.jpg)
Hegel’s Statement
“Beauty is substance of imagination and feeling, cannot be an exact
sign”
![Page 8: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/8.jpg)
Outline• Light and Color
– Description of Light• Quality of light
– Description of Color• Munsell Color System• Hue, Chroma, Value
– Factors influencing perception • The eye (rods and cones)
• Shade selection– Techniques for determining shade / Shade guides– Shade mapping
![Page 9: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/9.jpg)
Visible electromagnetic energy whose wavelength is measured in nanometers (nm)
![Page 10: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/10.jpg)
Without Light Color Does Not ExistWithout Light Color Does Not Exist
![Page 11: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/11.jpg)
We are going to understand the basic relationship of light ,color and visual perception
![Page 12: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/12.jpg)
•The eye is only sensitive to the visible portion of the spectrum (380 – 750nm)•Different wavelengths constitute the different colors we perceive
![Page 13: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/13.jpg)
Main sources of light
The Sun
The Fire
![Page 14: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/14.jpg)
Principle sources of artificial light
![Page 15: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/15.jpg)
Incandescentlight
FlorescentTube
PhotographicFlash
![Page 16: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/16.jpg)
• When passed through a prism we see component colors of white light
• Shorter wavelengths band more than longer wavelengths
Pure White Light
380nm
750nm
![Page 17: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/17.jpg)
![Page 18: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/18.jpg)
Quality of Light / 3 Types
1. Incandescent Light
2. Fluorescent Light
3. Natural Daylight
Most dental offices are outfitted with incandescent and fluorescent lights
![Page 19: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/19.jpg)
1. Incandescent Light• Emits high concentration of yellow waves• Not suitable for shade matching
![Page 20: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/20.jpg)
2. Fluorescent Light• Emits high concentration of blue waves• Not suitable for shade matching
![Page 21: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/21.jpg)
3. Natural Daylight• Northern daylight considered the best • Closest to emitting the full spectrum of
white light• Used as the standard by which to judge
other light sources
![Page 22: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/22.jpg)
Color Rendering Index• CRI = (0-100)
• Shade selection is done with a light having more than 90 CRI
• Northern daylight (hence CRI) affected by– Time of day– Cloud cover– Humidity– Pollution
![Page 23: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/23.jpg)
CRI and Time of DayMorning and evening Mid-day
![Page 24: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/24.jpg)
Color is the subjective impression formed in a specific portion of
brain owing to the specialization of certain cells-rods and cones
distributed in retina of the eye
![Page 25: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/25.jpg)
![Page 26: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/26.jpg)
ColorInfluenced by three main factors
1. Physical properties of the object
2. Assessment of the observer
3. Nature of incident light
Relationship to other colored objects
![Page 27: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/27.jpg)
A surface of an object appears red for an example when it reflects long waves but absorb light or the complementary color blue
![Page 28: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/28.jpg)
“Light that enters the human eye from that object”
Dimensions of Color
![Page 29: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/29.jpg)
• Numerous scientist came with the approach to tell about the part of the color but it was Munsell’s(1961) system which best serves to rank the color coz it view differences between neighboring color at regular interval
• Hue, value, chroma are very well presented in Munsell's’ color scale
![Page 30: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/30.jpg)
![Page 31: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/31.jpg)
• This system was intended for evaluation of opaque surface and therefore not fully applicable for teeth whose surface are translucent
![Page 32: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/32.jpg)
• Therefore 4th dimension that of translucency has to be added in the system
• Hence 4 dimension of color –hue, value, chroma and translucency – should be quantified as clearly and accurately as possible in defining the natural tooth or ceramic color
![Page 33: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/33.jpg)
Translucency • The degree to which light is transmitted
rather than absorbed or reflected • Highest translucency is transparent • While lowest is opacity
![Page 34: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/34.jpg)
Perception of Color
![Page 35: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/35.jpg)
Color Perception• Rods
– Scotopic (gray scale) vision, interpret brightness
• Cones
– Highest concentration on central retina (macula), most color perceptive area of eye
![Page 36: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/36.jpg)
Color Adaptation• Color vision decreases rapidly as object is
observed– Leads to retinal Fatigue
• Viewing a pale blue or gray surface between shade matching will restore color vision
![Page 37: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/37.jpg)
MetamerismTwo colors that appear to be a match under a
given lighting condition but have different spectral reflectance = metamers, the
phenomenon is metamerism.
1st Light source 2nd Light source 3rd Light source
![Page 38: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/38.jpg)
![Page 39: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/39.jpg)
Shade selection
![Page 40: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/40.jpg)
Shade Selection
• Timing• Lighting• Patient preparation• Shade guides
Conventional
Custom made
Technology based shade guide systems
![Page 41: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/41.jpg)
Principles of Shade Selection
1. Teeth to be matched must be clean2. Remove bright colors from field of view
- makeup / tinted eye glasses- bright gloves- neutral operatory walls
3. View patient at eye level
![Page 42: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/42.jpg)
Principles of Shade Selection ……
4. Evaluate shade under multiple light sources
5. Make shade comparisons at beginning of
appointment
6. Shade comparisons should be made quickly to
avoid eye fatigue
![Page 43: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/43.jpg)
Commercial Shade Guides• Most common method of making shade
selections• Guides consist of shade tabs
– Metal backing– Opaque porcelain– Neck, body, and incisal color
• Select tab with the most natural intraoral appearance
![Page 44: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/44.jpg)
Commercial Shade Guides
• Vita Classic
• Vitapan 3D –Master
• Extended Range Shade Guides
![Page 45: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/45.jpg)
Vita Classic Shade Guide
A B C D
• Very popular shade guide
• A3 = hue of red-yellow, chroma of 3
![Page 46: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/46.jpg)
Red/Yellow Yellow GreyGrey
Red/Yellow
A B C D
![Page 47: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/47.jpg)
Vita Classic – Step 1 (Hue Selection)
Operator should select hue closest to that of natural tooth
![Page 48: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/48.jpg)
The intensity or saturation of a hue
Low Chroma High Chroma
Chroma
![Page 49: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/49.jpg)
Vita Classic – Step 2 (Chroma Selection)
• Hue selection has been made (B)• Chroma is selected from gradations within the B
tabs-B1, B2, B3, B4
Several comparisons should be madeAvoid retinal fatigue
Rest eyes between comparisons (blue-gray)
![Page 50: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/50.jpg)
Value
• The relative darkness or lightness of a color, or brightness of an object
Low Value High Value
![Page 51: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/51.jpg)
Vita Classic – Step 3 (Value Selection)
• Value oriented shade guide– B1, A1, B2, D2, A2, C1, C2, D4, A3, D3, B3, A3.5, B4, C3, A4, C4,
Value best determined by squinting with comparisons made at arms length
Decreases light Diminishes cone sensitivity, increases rod sensitivity
![Page 52: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/52.jpg)
- Equal in Chroma / Variation in Value- Variation in Chroma / Equal in Value
Chr
oma
Value
![Page 53: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/53.jpg)
Vita Classic – Step 4 (Final Check / Revision)
• Potential Problem–tabs selected for hue and
chroma may not coincide with shade tab selected for value
![Page 54: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/54.jpg)
VITAPAN 3D-MASTER Shade Guide
1 23 4
5
![Page 55: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/55.jpg)
Vita-3D – Step 1• Determine the lightness level (value)
• Start with darkest group moving right to left
• Select Value group 1, 2, 3, 4, or 5
![Page 56: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/56.jpg)
Vita-3D – Step 2• Select the chroma
• From your selected Value group, remove the middle tab (M) and spread the samples out like a fan
• Select one of the three shade samples to determine chroma
![Page 57: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/57.jpg)
Vita-3D – Step 3• Determine the hue
• Check whether the natural tooth is more yellowish or more reddish than the shade sample selected
![Page 58: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/58.jpg)
Vita-3D – Step 4• For more precise shade, intermediate
levels for hue, value, and chroma can be given– 2.5M2 = value between 2M2 and 3m2– 3M1.5 = chroma between 3M1 and 3M2– 3M2 / 3L2.5 = hue between 3M2 and 3L2.5
![Page 59: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/59.jpg)
Extended Range Shade Guides
• Some porcelain systems extend the typical range
• Bleached shades
• Dentin shades
• Custom shade guides
![Page 60: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/60.jpg)
![Page 61: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/61.jpg)
Vita Easy shade.
Shade Eye
Shade Scan.
Advancements in Shade selection
Spactroshade.
![Page 62: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/62.jpg)
Importance of luting agent • Luting agent shade is also important
consideration for the imparting proper shade
• As it imparts color through the restoration
![Page 63: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/63.jpg)
Range for natural teeth
• Value in natural teeth 4 - 8
• Chroma in natural teeth 0 - 7
• Hue in natural teeth 6 YR - 9.3YR
![Page 64: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/64.jpg)
Limitation of shade guide • Don’t tell about the complete tooth color.
• Shade guide is prepared by different materials and crowns are of different.
• Problem we face for selecting shade for porcelain fused to metal crown.
![Page 65: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/65.jpg)
![Page 66: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/66.jpg)
Shade Mapping• Tooth is divided into
– Three regions– Nine segments
• Each region is matched independently• Further characterizations are sketched on diagram, may include…
– Craze lines– Hypo calcifications– Proximal discolorations– Translucency
![Page 67: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/67.jpg)
Summary• An understanding of the science of color and color perception is
crucial to the success esthetic restorative dentistry.
• Although limitations in materials and techniques may make a perfect color match impossible, a harmonious restoration can almost be achieved.
• Shade selection should be approached in a organized manner.
• This will enable the practitioner to make the best choice and communicate it accurately to the laboratory.
![Page 68: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/68.jpg)
References • Contemporary Fixed Prosthodontics Rosenstiel (3rd
edition)• Esthetics in dentistry Ronald E Goldstein• Esthetics dentistry; a clinical approach to technique and
materials Barry G Dale, Kenneth W Aschheim• Esthetic dentistry and ceramic restoration Martin Dunitz• Tylman’s Theory and practice of FPD• Natural Color Concept: A Systematic Approach to Visual
Shade Selection Bernhard Egger• Shade selection By Christopher CK Ho, BDS Hons
(Syd),
![Page 69: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/69.jpg)
What we say till now is just the tip of ice berg
Greater knowledge is still awaiting to be discovered and practiced about
esthetics
![Page 70: Shade Selection](https://reader030.fdocuments.us/reader030/viewer/2022013110/546c92e0b4af9f447b8b465c/html5/thumbnails/70.jpg)
Thank You
Have a nice day