Terminology and Biomechanical considerations

Operative Dentistry Exam 1

Operative dentistry

Operative dentistry is the art and science of the prevention, diagnosis and treatment of defects in the enamel, dentin and cementum of teeth

Restorative dentistry

Restorative dentistry is the study, diagnosis and integrated management of

diseases of the teeth and their supporting structures and the rehabilitation of

the dentition to functional and aesthetic requirements of the individual.

Preventive dentistry

Aspects of dentistry concerned with promoting good oral health and

function by preventing or reducing the onset and/or development of oral

diseases or deformities and the occurrence of oro-facial injuries.

Cosmetic dentistry

Cosmetic dentistry is generally used to refer to any dental work that

improves the appearance of teeth, gums and/or bite. It primarily focuses on

improvement in dental aesthetics in color, position, shape, size, alignment

and overall smile appearance

Caries

Commonly used term for tooth decay

Carious Lesion

A cavity caused by caries

Cavity

Missing tooth structure. A cavity may be due to decay, erosion or abrasion.

If caused by caries; also referred to as carious lesion

Decay

Lay term for caries

Filling

A lay term used for the restoring of lost tooth structure by using materials

such as metal, alloy, plastic or porcelain

Direct restoration

A restoration of any type (e.g., “filling”; crown) fabricated inside the mouth

A procedure where the service is delivered completely in the patient’s oral

cavity and without the use of a dental laboratory..

Indirect restoration

A procedure that involves activity that occurs away from the patient, such

as creating a restorative prosthesis. An indirect procedure is also known as a

laboratory procedure, and the laboratory’s location can be within or

separate from the dentist’s practice.

Temporary restoration

A restoration or prosthesis placed for a shorter time interval for use while a

definitive restoration or prosthesis is being fabricated –

see interim and provisional.

Preparation

Is the mechanical alteration of a defective, injured, or diseased tooth to

receive a restorative material that re-establishes a healthy state for

the tooth, including esthetic corrections where indicated and normal form

and function.

Treatment Plan

The sequential guide for the patient's care as determined by the dentist's

diagnosis and is used by the dentist for the restoration to and/or

maintenance of optimal oral health.

Diagnostic imaging

A visual display of structural or functional patterns for the purpose of

diagnostic evaluation. May be photographic or radiographic.

Radiograph

An image or picture produced on a radiation sensitive film, phosphorous

plate, emulsion or digital sensor by exposure to ionizing radiation

Anatomy of the Tooth Crown

1. Enamel

2. Dentin

3. Dentino Enamel Junction

4. Pulp horn

5. Pulp Chamber

1. Enamel

1. Dentin

Dentino Enamel Junction

Pulp horn

Pulp Chamber

Anatomy of the Tooth Root

Dentino-Enamel Junction (DEJ)

Where enamel meets dentin

Cemento-Enamel Junction (CEJ)

: Where enamel meets cementum

Anatomical Crown

is that part of the tooth that is covered by Enamel

or outer covering of the tooth. Its up to the cementoenamel junction.

Clinical crown

is that part that is visible in the oral cavity.

Hard Tissue Composition (Enamal)

Hard Tissue Composition (Dentin & Cementum)

Inorganic Hard tissue composition (3)

Carbonated apatite

• Hydroxy-apatite

• Fluro-apatite

Organic Hard tissue composition (3)

• Lipids

• Proteins

• Collagen

enamel rod

An enamel rod is the basic unit of tooth enamel. It is a tightly packed, highly organized mass of

hydroxyapatite crystals, which are hexagonal in shape and provide rigidity and strengthen the enamel

Perikymata

are incremental growth lines that appear on the surface of tooth enamel as

a series of linear grooves.

Enamel Has …

Enamel has diffusion channels that allow for acid or ionic exchange

Enamel

Enamel rods

• Interrod enamel:

- Located around the rod

enamel

- Same composition as enamel

rod

- Different direction

• Rod sheath: Contains proteins,

water, and lipids

Enamel rods/prisms Location

Enamel rods/prisms exit

perpendicular to tooth surface

dentinal tubules

Dentin consists of microscopic channels, called dentinal tubules, which radiate outward through the dentin from

the pulp to the exterior cementum or enamel border.

Dentin vs Enamel

Hydroxyapatite crystals are 30 times smaller, making

dentin somewhat softer than enamel.

Dentin is duller and darker in appearance

Peritubular dentin

is a relatively dense mineralized tissue that surrounds the dentinal

tubules. It is composed mainly of crystals of carbonated/hydroxy apatite together

with a small amount of collagen

intratubular dentin

The intertubular dentin, which lies between the tubules, is a less-calcified matrix that

consists of some apatite crystals embedded within a collagen matrix.

intratubular dentin vs Peritubular dentin

Very Important about Dentin Tubules

The number and diameter of the tubules increase from DEJ to the pulp

Types of Dentin (4)

Primary dentin

• Secondary dentin

• Tertiary dentin:

• Sclerotic dentin: Hypermineralized dentin, Darker, Non-carious, not necessary to remove

Primary dentin:

First dentin deposited during development

• Secondary dentin

: Dentin deposited as a process of normal aging

Tertiary dentin:

Dentin deposited in response to trauma

Sclerotic dentin:

Hypermineralized dentin, Darker, Non-carious, not necessary to remove

Pulp

Connective tissue that contains blood vessels and nerve tissue which

occupies the pulp cavity of a tooth.

Function of Pulp

Formative: Generates primary, secondary, and tertiary dentin

(dentinogenesis)

• Nutritive: Provides the vascular supply and ground substance transfer

medium for metabolic functions and maintenance of cells and organic

matrix

• Sensory: Transmits afferent pain sensation

• Protective: Coordinates inflammatory responses to injury

Hydrodynamic Theory of Pulpal Pain

Inflammation→

Swelling of odontoblasts→

Occlude dentinal tubules→

Increased pressure and sensitivity to fluid movements in the tubules

Causes of Pulpal Inflammation (4)

Bacterial Influences

Desiccation

• Overly drying the dentin especially after etching dentin

Heat Damage

• Bur friction

• Polymerization of temporary & composite materials

Osmotic Changes

• Sweets

Biomechanical Factors affecting Pulpal Health (4)

Depth and extent of preparation

• Bur used (dull bur)

• Bur rotation (too much pressure, leaving the bur static

when drilling)

• Use of coolants (water)

Universal numbering system

Four Quadrants of the Mouth

Tooth surfaces (8)

• B buccal surface

• I incisal edge

• F facial surface

• O occlusal surface

• L lingual surface

• D distal surface

.

• M mesial surface

• P Palatal surface

O occlusal surface

I incisal edge

• F facial surface

P Palatal surface

M mesial surface

D distal surface

L lingual surface

B buccal surface

G.V. Black classes

• 6 of Them

• Based on location only

G.V. Black Class I (Three Types)

• Pits and fissures of occlusal surfaces of posterior

  teeth (premolars and molars)

• Pits in the occlusal 2/3 of facial and

  lingual surfaces of molars

• Smooth proximal surfaces of posterior teeth

  (premolars and molars)

Pits in the occlusal 2/3 of facial and

lingual surfaces of molars

Smooth proximal surfaces of posterior teeth

(premolars and molars)

G.V. Black Class II

Smooth proximal surfaces of posterior teeth

(premolars and molars)

G.V. Black Class III

Smooth proximal surfaces of anterior teeth

(incisors and canines)

G.V. Black Class IV

Smooth proximal surfaces of anterior teeth (incisors and

canines) which involve the incisal edge as well

G.V. Black Class V

Smooth surfaces of all teeth in gingival 1/3 of facial and lingual surfaces Class V

G.V. Black Class VI

Incisal edges of anterior teeth and occlusal cusp tips of posterior teeth

ICDAS

(International Caries detection and assessment system)

From 1 to 6 → How strong is the bacterial caries infection

ADA Codes for Caires

1 to 6

Diagnostic data needed (6)

1. Caries risk assessment

2. Medical and dental

   history

3. Patient exam and

   charting

4. Intra and extra oral exam

5. Diet

6. Occlusion

Four Tests for Data Gathering Information

Trans-illumination

Trans-illumination of a cracked tooth and

proximal caries

Pulp Vitality Testing (2)

Prioritizing treatment of Caries (3 Phases)

Phase I

Emergencies

• Infections

• Prevention

• Gingival health

• Sealants

Phase II

Simple restorations

Phase III

Complex restorations