smile Analysis

Smile design parameters

Tooth shape, proportion, anatomy, color, value, and translucency

Main goal of smile design

Replicate natural esthetics through observation and understanding patient expectations

Old concept of tooth morphology

Teeth shape correlated with head shape (now considered inaccurate)

Current understanding of tooth shape

No direct relationship with head shape, gender, or ethnicity

Maxillary anterior tooth inclination

Central incisors tilt inward, laterals tilt slightly more, cuspids also tilt inward

Mandibular anterior tooth inclination

Anterior teeth tilt slightly outward, cuspids tilt inward

Planes of a tooth

Three planes exist on each tooth

Labial surface shapes

Convex, flat, and concave

Tooth shape variations

Round or square on mesial and/or distal surfaces

Factors controlling tooth shape and proportion

Root shape, root rotation, bone, and tissue preparation

Importance of midline in esthetics

Facial harmony of the midline is critical; small discrepancies elsewhere become less important

When esthetics appear natural

When teeth match in length, angulation, contours, and gingival sculpting

Primary anatomy

Basic shape and form of the tooth established first

Secondary anatomy

Texture and surface details added after primary anatomy

Effect of smooth surface on restorations

Appears more translucent and lower in value

Effect of rough surface on restorations

Appears brighter and less translucent

Types of tooth texture

Broad horizontal, narrow horizontal, vertical striations, and dimpled texture

Materials used in CAD/CAM restorations

Metal, alumina, zirconia, lithium disilicate ceramics

Traditional restoration process

Labor-intensive: layering, sculpting, baking, staining, glazing

Modern restoration process

Milling from ceramic blocks using CAD/CAM technology

Main difference between traditional and digital restorations

Time efficiency (digital is faster)

Digital dentistry benefits

Improved communication, efficiency, and treatment planning

Role of observation in smile design

Essential for replicating natural esthetics

Diagnostic wax-up

Predictive model used before treatment to plan final restorations

Purpose of provisional restorations

Evaluate esthetics and function before final restorations

Technician's responsibility

Copy approved provisional restorations into final restorations

Full-coverage restorations

Used when changing tooth shape, position, and function

Goal of esthetic dentistry

Duplicate natural dentition with function and beauty

Digital workflow steps

Data collection → digital design → milling → final restoration

Limitations of traditional techniques

Less efficient, more labor-intensive, less predictable

Digital articulator

Simulates occlusion and functional movements in 3D

Importance of occlusion in CAD/CAM

Automatically considered in digital design systems

Key concept of esthetics

Small asymmetries can still look natural

Anterior guidance

Functional relationship of anterior teeth during movement

PMMA provisional restorations

Temporary restorations made from polymethylmethacrylate

Lithium disilicate restorations

Strong, esthetic ceramic restorations (e.max)

Zirconia coping

Base structure layered with ceramics for esthetics

Digital smile design

Use of software to plan and visualize final smile outcomes

Ultimate goal of CAD/CAM dentistry

Perfect duplication of natural teeth with efficiency and precision