Proportional Smile Design Daniel H Ward DDS 1080 Polaris Pkwy Ste 130 Columbus OH

Transcription

1 Proportional Smile Design Daniel H Ward DDS 1080 Polaris Pkwy Ste 130 Columbus OH dward@columbus.rr.com Incisal Placement Incisal plane parallel to the interpupillary line Vertical midline in the center of the face perpendicular to the interpupillary line centered with the philtrum Determinants of incisal edge position 1. esthetics 2. phonetics: f, v, th (Pound) 3. anterior guidance/occlusion Incisal edges follow curvature of the lower lip Clinical crown outlined by upper and lower lip, marginal gingiva display confined to interdental papilla Curve of Spee

2 Tooth Positions & Relationships (Rufenacht, Morley) Roots of anterior teeth diverge apically as you move distally Incisal embrasures become larger as you move distally Contact points move apically and incisal embrasures become larger as you move distally Connector area Incisal and cervical length of lateral incisors may be slightly shorter than central incisors and cuspids Cervical of central incisors and cuspids are parallel

3 Buccal Corridor 1. Visual area of buccal surfaces of posterior teeth 2. Ideally space is visually filled in 3. Negative space is when visual area contains vacancies between buccal surfaces of teeth and buccal mucosa Apical Zenith distal to midline of long axis of the tooth (feminine lateral incisor may be at midline) (Chu, Morley) Individual Max Tooth Characteristics (Frush & Fisher, Lombardi, Morley) SPA Factor-(sex=lateral incisor, personality=cuspid, age=central incisor) Central Incisors-mirror images-dominance Lateral Incisors-variations-gender-shorter than central incisors 0.5-1mm Cuspids- aggressiveness

4 Teeth May Mimic Inverted Face Form (Williams, Leon) Aging of a Smile (Gurel, Vig & Brundo) Flattened Incisal edges Smaller incisal embrasures Smoother facial anatomy Prominent mandibular display Increased chroma Anterior Splaying Common Facial Proportions Rule of Fifths Rule of Thirds

5 Tooth Proportions Width of anterior six teeth in golden proportion to intercommisural width Central Incisor is 1/16 the width of inter-zygomatic width (House) Central Incisor is 1/16 the length from ideal hairline to the chin(house) Dentsply Tooth Size Indicator-

6 Smile Design Tooth Width Proportion Theories Golden Proportion (Levin) Golden Mean (Snow) Naturally occurring (Preston) RED Proportion (Ward)

7 Width/Height Ratio of Central Incisor (Sterrett, Wolfart) Relationship of tooth length and RED Proportion (Rosenstiel, Ward, Rashid) 75-78% w/h ratio of maxillary central incisor preferred by dentists Normal length teeth-70% RED Very tall teeth-62% RED (Golden Proportion) Very short & short teeth-80% RED Taller teeth gives more dominant Central Incisor Patient preferences (Carlssan Jørnung, Ker, Rosenstiel, Wagner Wolfart)

8 Using RED Proportion to determine size of maxillary anterior teeth(ward) Step 1 Determine Relative Tooth height (Very tall, Tall, Normal, Short, Very Short) Step 2 Measure facial view Intercanine Width (ICW) Step 3 Divide ICW by appropriate tooth height column divisor (After determining Central Incisor width multiple times appropriate RED proportion) Calculating RED & anterior total widths from inter-canine width(icw)-divisors Tooth Height RED Central Incisor Width Lateral Incisor Width Canine Width Very Tall 62% RED ICW/ 4.0 CIW *.62 LIW *.62 Tall 66% RED ICW/ 4.2 CIW *.66 LIW *.66 Average 70% RED ICW/ 4.4 CIW *.7 LIW *.7 Short 75% RED ICW/4.6 CIW *.75 LIW *.75 Very Short 80% RED ICW/4.8 CIW *.8 LIW *.8 Step 4 Divide CIW by 0.78 (78%) for CIL

9 Simplified Method Using ICW & CIL to determine size of maxillary anterior teeth maintaining incisal length(ward) Step 1 Measure frontal view Intercanine width (ICW) and Central Incisor Length (ICL) Step 2 Divide (ICW) by Central Incisor Length (ICL) to obtain quotient Step 3 Lookup quotient in chart for appropriate divisors to divide ICW by to obtain appropriate facial widths Calculating RED & Individual tooth widths from ICW& CIH-Divisor chart ICW/CIL=Quotient RED Central Incisor Width Lateral Incisor Width Canine Width % RED ICW/ 4.00 ICW/6.47 ICW/ % RED ICW/4.15 ICW/6.38 ICW/ % RED ICW/ 4.24 ICW/6.33 ICW/ % RED ICW/4.38 ICW/6.26 ICW/ % RED ICW/4.53 ICW/6.20 ICW/ % RED ICW/4.63 ICW/6.17 ICW/ % RED ICW/4.78 ICW/ 6.12 ICW/ % RED ICW/4.88 ICW/6.10 ICW/7.63 Step 4 Divide CIW by 0.78 (78%) for CIL

10 Simplified Method Using ICW & desired CIL to determine size of maxillary central incisor & RED Proportion(Ward) Step 1 Measure frontal view Intercanine width (ICW) Step 2 Determine desired Central Incisor Length (DCIL) Step 3 Divide (ICW) by desired Central Incisor Length (ICL) to obtain quotient Step 4 Lookup quotient in chart for appropriate divisors to divide ICW by to obtain central incisor facial width and appropriate RED Proportion RED proportion for desired central incisor length ICW/DCIL=Quotient Tooth Height RED Proportion Central Incisor Width 3.1 Very Tall 62% RED ICW/ Tall 66% RED ICW/ Normal 70% RED ICW/ Short 75% RED ICW/ Very Short 80% RED ICW/4.8

11 Esthetic Periodontal Surgery(Gargiulo, Wentz & Orban, Kois) Adding length to Central Incisor allows a smaller RED Proportion Methods to gain length Biological Width-1mm sulcus, 1mm epithelial attachment, 1mm ct FGM 3mm coronal to osseous crest Communication with periodontist 1. Guide Incisal Edge 2. Desired length from guide incisal edge to free gingival margin 3. Teeth to be treated

12 FACIAL SMILE EVALUATION Name Date Do you like your smile? Yes No What would you like to change about your smile? Would you prefer? Ideal Perfect Smile Natural Smile with individuality How do you like the color of your teeth? What shade would you like them to be? Alignment-Draw lines Cant Midline Smile Curve Vertical Incisal Edge

13 Draw outlines Gingival Heights Incisal Heights Circle appropriate display Inadequate Incisal Display Ideal Incisal Display Covered Incisal Edges Filled Buccal Corridor Dark Buccal Corridor Excess Gingiva Circle areas Black Triangles Major Areas of Concern Teeth to be Treated Periodontal Concerns Referrals Needed

14 BLUEPRINT WORKSHEET Patient Cast Length Central Incisor mm Photo Length Central Incisor mm Ratio Width Length Cast length = (Conversion factor) Photo Length Pre Treatment Photo Measurements Conversion Factor = Width Length Converted Cast Measurements (Photo measurements X Conversion Factor) Width/Length Ratio 8 9 RED Proportion Width Length Conversion Factor = Width Length 5/6 6/7 7/8 8/9 10/9 11/10 12/11 Desired Post-Treatment(Cast Measurements) Converted Photo Measurements (Cast measurements/conversion Factor)