Considerations in

Fixed Prosthodontics

Esthetic

Contents

•Introduction

•Artistic and Scientific Principles Applied to Esthetic Dentistry

•Esthetic Diagnosis And Treatment planning

• Color and Shade Selection

•Replacement Of Deficient Crowns

•Metal Ceramic Crowns

•All Ceramic Crowns

•Tissue Management & Impression Making for Maxillary Anterior Region

•Provisional Restorations

•Communication with the Dental Laboratory And Try in

•Conclusion

•References

Introduction

Artistic and Scientific Principles

Applied to Esthetic Dentistry

Factors of Esthetic Dentofacial Composition

Frame and Reference: the constructional system that gives shape;a standard for measuring or constructing.

Proportion and Idealism: the relation of one part to another or to the whole

with respect to magnitude,quantity,or degree;a standard of perfection,beauty,or excellence.

Symmetry: the correspondence in size,shape,and relative position of parts on opposite sides of a dividing line or median plane or around a center or axis.

Perspective and Illusion: the technique or process of representing on a plane or curved surface the spatial relation of objects as they might appear to the eye.

Inter pupillary line

• Incisal plane

• Gingival margin

• Maxilla

• canting

Horizontal References

Frame and Reference

Vertical references

Facial Midline

•Location and axis of midline

•Mediolateral discrepancies in tooth position

Golub 1988 said that dental midline perpendicular to the interpupillary line offers one of the most striking facial contrast, serving to anchor the smile

Saggital references

Upper lip support

Lower lip relation

Maritato & Douglas 1964 suggested that lip support is a better guide of tooth position than of Incisal edge position.

Occlusal plane

Phonetic references

M sound

F-V sounds

S-sound or Z sound

Smile elements Lip and Lip Lines

Upper lip line

Length of Maxillary Incisors

Vertical position of the gingival margins

Low Medium High

Lower lip line

Buccolingual position

Curvature of incisal plane

Vig and Brundo 1978 demonstrated that the average maxillary incisor display with the lips at rest

Men 1.91mm Women 3.4mm

Long lips 0.56mm Short lips 3.37mm

Younger pt upto 29 yrs

3.37mm Middle aged 30-50 yrs

1.26mm

Smile

Negative Space

Passive

Active(Moderate)

Laugh

Gummy smile

Smile Line

Youth

Aged

Gull wing appearance

Straight smile line

Proportion and Idealism

Lombardi RE 1973 pointed to the importance of the proportion between width and length in the dimensions of individual teeth and between the respective size of the anterior teeth.

Golden Proportion

Symmetry and Diversity

Patients preferences

Brisman 1980 demonstrated that many patients prefer equilibrated smile arrangements with either alike teeth on a straight incisal plane or a normal sized teeth on a mildly convex incisal plane.

Pleasing natural symmetry

Natural Varitions

•Dental midline Miller et al 1979

•Maxillary central incisors

Mavroskufis F,Ritche GM 1980

•Maxillary lateral incisors

•Maxillary canine

Perspective and illusion

Altering perception of an individual tooth

Normal Widening Narrowing shortening lengthening

Altering perception between teeth

Perspective by contrast

Shading perspectiveParallel perspective

Esthetic Diagnosis and Treatment planning

Diagnosis

Preliminary analysis

Patient History

Clinical Examination

Diagnostic Records

Total Smile analysis

Visual analysis

Space analysis

Profile analysis

Computer analysis

Space Analysis

Profile Analysis

Computer Analysis

• Initial Therapy

• Scaling and Root planning

• Replacement of Deficient crowns

• Mock up

Color and Shade Selection

“Light that enters the human eye from that object”

Dimensions of Color

Color of Human teeth

•Clark 1931was the first to accurately describe the color of the teeth

He found Hue range 6YR-9.3Y Value 0-7

•Sproull Hue range of 7.5YR-2.7Y Value 5.8-8.5 Chroma 1.5-5.6

•Lemire and Burks Hue 8.9YR-3.3Y Value 5.81-7.98 Chroma .8-3.4

Shade Selection

• Timing

• Lighting

• Patient preparation

• Shade guides

Conventional

Custom made

Technology based shade guide systems Shofu shade master-ex chromameter

Coretex machina shade scan

Shade matching with VITAPAN 3D-MASTER

Step 1 : Value determination

Step2 : Chroma determination

Step 3 : Hue verification

Color communication form

Orthodontic considerations

Inclined Incisal plane

Deviated Midline

Periodontal considerations

Restorations for a previously restored dentition

Reestablishing proper “biologic width”

Violation of “biologic width”

“Biologic width”

Correction of Non inflammatory periodontal defects

Replacement of Deficient Crowns

• Frequent mistakes found in Deficient crowns

Incisal plane – Too Straight, CantedIncisal length –C I too narrow L I too wide

Incisal profile- over contoured

• Retreatment of Deficient Crowns

Phase 1

Phase 2

Phase 3

Remove the existing crowns, Reprepare the abutments, Scale and root plane

Determine the proper shape and incisal edge position in the provisional and refine accordingly

Harmonize anterior guidance

Reevaluate pulp status, gingival defects, anterior guidance, and tooth mobility

Finalize crown build ups,axial reduction and margin placement.

Complete final restorations

Restorative dentistry considerations

• Bleaching

• Direct composite resin bonding

• Porcelain laminate veneers

• Resin-bonded Fixed Partial Denture

• Full coverage crownsMetal ceramic crowns

All ceramic crowns

Office

Home

Vital tooth (Power bleach)

Non vital tooth (walking bleach)

10-15% Carbamide peroxide

35% Hydrogen peroxide

35% Carbamide peroxide

•Bleaching

Direct composite resin bonding

Advantages

Immediate esthetic result

Patient satisfaction in one to two visits

Conservative

Relatively low cost

Dis advantages

Repeated chipping

Discoloration

Porcelain laminate veneers

Porcelain laminate veneers

Tetracycline stains

Peg shaped lateral

Resin-bonded Fixed Partial Denture

Metal ceramic crowns

Finish lines

Butel EM,Campbell J C,Difiore PM 1991 conducted a survey of 51 Dental schools

Flat shoulder 38% 45 beveled shoulder 24% 135 shoulder 15% Chamfer 10% Deep chamfer 6%

Margin placement

• Color rendition

Facial reduction 1.4mm

Tooth thickness 2.9mm

Thickness requirements according to shade

Facial reduction 1.7mm

Tooth thickness 3.2mm

Dark Shade

Light Shade

Ideal Difficult

Compensation for thin teeth

Opposing teeth reduction

Lingual stop Lingual plate

All Ceramic crowns

Selection

Esthetic Performance

Semi-translucent

Semi-opaque

Indications

All anterior teeth where esthetics is of prime importance

Contraindications

Para function Short clinical crown Insufficient support from tooth preparation Faulty occlusion

• Preparations for All Ceramic Crowns

Incisal Reduction

Facial and Lingual Reduction

Shoulder

Taper

Impressions for Anterior Dentition • Gingival Retraction

• Retraction TechniquesSingle String technique

Selective Double String technique

Double String technique

Loe and Silness 1963 showed that with normal pressure, Strings had the potential to be pushed into the supracrestal connective tissue

Dargoo and williams 1981 demonstrated that retraction cord placement following sub gingival preparation often tore the epithelial and connective tissue attachments

Albers 1990 said that aluminium chloride is the chemical of choice to prevent recession of thin delicate gingival tissues in the anterior region

Communication with the Dental Laboratory

• Goals

•Predictable try-in

•Minimum adjustment of crown restorations

• Methods of Achieving Goals

•Proper Occlusion and Orientation of the Master cast

•Determination of Incisal edge position

•Communication of tooth shape and arrangement

•Proper shade Prescription

Orientation of the Master Cast

Esthetic orientation

Occlusal orientation

•Roach RR,Muia Lee 1990

•PJ 1988

•Orientation Techniques

• Face bow Transfer

•Inter Occlusal Recording

•Anterior Guidance

Conclusion

References1. Esthetics of Anterior Fixed Prosthodontics

Gerard chiche

2. Esthetic Dentistry

Ratnadeep patil

3. Perspectives in Dental Ceramics: Proceedings of the fourth international symposium on ceramics, Chicago 1988 Quintessence

4. Fundamental in Esthetics

Claude R Rufenacht

5. Fundamentals of Fixed Prosthodontics 3rd edition

Herbert T. Shillingburg

6. Johnston’s

Modern Practice in Fixed Prosthodontics 4th edition Ronald w. Dykema 7. Contemporary Fixed Prosthodontics 3rd edition Stephen F.Rosensteil

8. J Prosthet Dent 1955 ;5:586

9. J Prosthet Dent 1956;6:441

10. J Prosthet Dent 1961;11:743

11. J Prosthet Dent 1964;14:848

12. J Prosthet Dent 1973;29:358

13. J Prosthet Dent 1980;43:254

14. J Am Dent Assoc 1988;38

15. Int J Periodont Rest Dent 1988;8(3):45-55

16. J Esthet Dent 1994;6(2):47-60

17. Int L Prosthodont 2002;15:524-528

18. J Prosthet Dent 2003

19. J Prosthet Dent 2003

A smile is a curve that brightens several hearts

-So keep smiling always