
Chapter 18 Dental Assistant Skills
Career Highlights • Dental assistants are valuable members of the dental health care field • Education requirements • Certification obtained through the Dental Assisting National Board • Duties performed follow state regulations • Required skills
18:1 Identifying the Structures and Tissues of a Tooth • Odontology: study of the anatomy, growth, and diseases of the teeth • Teeth are accessory organs of thedigestive tract • Aid in mastication (chewing) of food
Two Sets of Teeth • Dentitions: sets of teeth • Primary or deciduous dentition • Permanent or succedaneous dentition
The Tooth • Crown—visible in the mouth • Root—below the gum line • Cervix—where the crown meets the root • Apex—tip of the root
Tissues of the Tooth • Enamel—covers the crown • Cementum—covers the outside of the root • Dentin—located under the enamel and cementum of the root • Pulp—in the inner area of the tooth
Periodontium • Structures that surround and support teeth • Alveolar process or ridge—surrounds the roots and has sockets • Periodontal ligament—supports the tooth in the socket • Gingiva or gums—surrounds the cervix
Dental Care • Disease can affect the teeth and supporting structures • Dental care • Preventing and treating dental disease • Preserving and prolonging the life of the teeth
18:2 Identifying the Teeth • Incisors—front and center of the mouth • Cuspids—at angles of lips • Bicuspids—before the molars • Molars—back of the mouth
Primary or Deciduous Teeth • First set of teeth—called “baby” teeth • 20 teeth • Naming of teeth
Permanent or Succedaneous Teeth • Second or permanent set of teeth • 32 teeth • Naming of teeth
18:3 Identifying TeethUsing Numbering Systems • Universal National Numbering System • Identified by using letters A to T • Federation Dentaire International System • Two-digit code and 4 quadrants
18:4 Identifying the Surfaces of the Teeth • Anterior (toward the front) teeth • Posterior (toward the back) teeth • Crown surfaces • Suggested abbreviations (continues)
Identifying the Surfaces of the Teeth(continued) • Line angles—form where two crown surfaces meet • Point angles—form where three crown surfaces meet • Abbreviations for line angles and point angles of anterior teeth • Abbreviations for line angles and point angles of posterior teeth
18:5 Charting Conditions of the Teeth • Conditions of the teeth are often charted on dental charts or insurance forms • Forms, symbols used, abbreviations, and other factors vary • Dental charts are legal records • Dental charts • Anatomic diagrams (continues)
Charting Conditions of the Teeth(continued) • Geometric diagrams • Surfaces of teeth • Charting guidelines • Common symbols for anatomic or geometric diagrams • Recording treatments or services • Use of computerized dental charting
18:6 Operating and MaintainingDental Equipment • Follow manufacturer’s recommendations for operation of equipment • Infection control • Personal protective equipment (PPE) • Occupational Safety and Health Administration (OSHA) • Covers for dental equipment (continues)
Operating and MaintainingDental Equipment(continued) • Dental light • Dental chair • Air compressor • Oral-evacuation system • Assistant’s cart • Tri-flow or air-water syringe • Saliva ejector (continues)
Operating and MaintainingDental Equipment(continued) • High-velocity oral evacuator • Cuspidor • Doctor’s cart • Low-speed hand piece • Contra angle for cutting and polishing • Prophylaxis angle for holding cups, etc. • High-speed handpiece (ultraspeed)
Summary • Responsibilities for care and maintenance of dental equipment will vary • Dental assistant should learn exactly what maintenance is expected as a part of the job • Read specific manufacturer’s instructions for equipment you will handle
18:7 Identifying Dental Instruments and Preparing Dental Trays • Methods for setting up dental trays • Organization of trays • Main parts of a dental hand instrument • Standard instruments • Guidelines for preparing dental trays • Examples of tray set-ups • Basic principles for preparing dental trays
18:8 Positioning a Patientin the Dental Chair • Designed to position patient comfortably while providing doctor and assistant easy access to oral cavity • Headrests • Supine position • Explanation of all chair movements • Protective drape and safety glasses • Positioning of light • Principles of seating patient in dental chair
18:9 Demonstrating Brushing and Flossing Techniques • Using correct brushing and flossing techniques is essential in prevention of dental disease • May be responsible for teaching patients • Correct brushing and flossing is one method of prophylactic care (continues)
Demonstrating Brushing andFlossing Techniques(continued) • Purposes • Demonstrations • Bass method • Five surfaces on each tooth • Toothbrushes • Toothpastes or dentifrices • Dental floss
Summary • Correct brushing and flossing provides prophylactic care • Give thorough explanation to all patients • Be sure patient understands procedures • Asking patient to demonstrate procedures is a good way to determine if all points have been learned
18:10 Taking Impressionsand Pouring Molds • Impression • Negative film reproduction of a tooth, several teeth, or a dental arch • Taken to form a model of the area for restoration treatment that will take place outside of the mouth • Common materials used to take impressions
Alginate • Hydrocolloid impression material that cannot be returned to its original state • Advantages • Disadvantages • Alginate powder—follow manufacturer’s recommended directions • Principles for taking alginate impression • Storage of alginate material
Rubber Base or Polysulfide • Elastomeric impression material that is elastic and rubbery in nature • Three types are available • Can be used in any type of dental impression • Not as subject to dimension changes as alginate (continues)
Rubber Base or Polysulfide(continued) • Models should be poured promptly if possible • Disadvantages • Basic principles of preparing rubber base
Silicones • Polysiloxane or polyvinylsiloxane • Available in different material qualities • Supplied in two tubes—base and catalyst • Advantages • Disadvantages
Gypsum Products • Two main products to form models • Plaster • Stone • Principles for the use of gypsum • Follow standard precautions for infection control when taking impressions and pouring models
18:11 Making Custom Trays • Impression trays that are made to fit patient’s mouth • Materials used to produce trays • Acrylic resins are self-curing or light-curing • Types of custom trays • Clean and replace all equipment
18:12 Maintaining and Loading an Anesthetic Aspirating Syringe • Anesthesia is used for pain control • Types of anesthesia • General anesthesia • Analgesia • Local anesthesia • Topical anesthesia
Injections • Two main kinds of injections for used for local anesthesia • Block • Infiltration • Types of medications • Anesthetic carpules (cartridges) • Aspirating syringes • Follow standard precautions
18:13 Mixing Dental Cements and Bases • Cements and bases used in variety of dental procedures • Terminology • Types of products • Basic principles of mixing cements and bases
18:14 Preparing Restorative Materials • Restoration: process of replacing a diseased portion of a tooth or a lost tooth by artificial means • May include filling material, crowns, bridge, denture, partial denture, or implant • Dental caries or decay
Amalgam • Restorative material used mostly on posterior teeth • Contains four main metals • Silver • Tin • Copper • Zinc (continues)
Amalgam(continued) • Mercury when added to other metals forms amalgam • Must be handled with care due to toxicity • Use protective clothing • Follow manufacturer’s recommendations
Composite • Restorative material used primarily for the repair of anterior teeth • Self-curing (chemical-curing) • Light-curing • Various shades to blend with teeth • Follow manufacturer’s instructions
18:15 Developing and MountingDental X-Rays • Dental X-rays or radiographs • Radiolucents • Radiopaque • Types of dental radiographs • Developing films • Mounting X-rays
Summary • The dental assistant acquires many skills • Use of these skills enables the dental assistant to perform or assist with many procedures in the dental care setting • Following procedures the assistant is often responsible for cleaning and care of equipment used