Comprehensive Dental Assistant Final Study Guide 2025-2026

General Program Information and Study Schedule

Final Test Date: May $12^{th}$ .
Program Title: $2025$ - $2026$ DA Program Vocabulary List and Study Guide.

Dentition and Dental Arches

Dentitions: Refers to all the natural teeth in the mouth. There are two dentitions: primary and permanent.
Periods of Dentition: There are three distinct periods: primary, mixed, and permanent.
Primary Dentition: Also known as deciduous, baby, or milk teeth. It consists of a total of $20$ teeth, with $5$ teeth per quadrant: two molars (posterior), one cuspid, and two incisors (anterior).
Permanent Dentition: Also called succedaneous or adult teeth. It consists of a total of $32$ teeth, with $8$ teeth per quadrant: three molars, two premolars (posterior), one cuspid, and two incisors (anterior).
Maxillary: Pertaining to the upper arch or jaw.
Mandibular: Pertaining to the lower arch or jaw.
Quadrant: Half of a dental arch, representing $\frac{1}{4}$ of the total dentition. The dentition is divided into four quadrants: UR (Upper Right), UL (Upper Left), LL (Lower Left), and LR (Lower Right).
Sextant: The dentition divided into six sections to separate posterior from anterior teeth. In permanent dentition, the divisions occur between teeth numbers $5$ - $6$ , $11$ - $12$ , $21$ - $22$ , and $27$ - $28$ .
Universal Identification System: The most common tooth identification system in the U.S. It uses numbers for permanent teeth and letters for primary teeth.

Tooth Anatomy and Classification

Incisor: An anterior tooth designed for cutting and biting.
Cuspid/Canine: An anterior tooth used for cutting and tearing. Known as the "cornerstones" of the dental arches, they have the longest roots in the mouth and are typically the last teeth to be lost.
Premolar/Bicuspid: A posterior tooth used for both grinding and chewing.
Molar: A posterior tooth used for grinding and chewing. Maxillary molars typically possess three roots, while mandibular molars typically have two roots.
Anterior: Situated toward the front.
Posterior: Situated toward the back.
Superior: Positioned above another part.
Inferior: Positioned below another part.
Proximal: Refers to tooth surfaces that are adjacent to one another in the dental arch.

Surface Anatomy and Structural Components

Contact Area/Point: The specific spot where the mesial or distal surface of a tooth touches an adjacent tooth. This maintains tooth position and protects tissues during mastication.
Mucosa: The soft tissue lining the oral cavity. * Masticatory Mucosa: Covers the alveolar process of the jaws and surrounds the cervixes of the teeth. * Lining Mucosa: Delicate, stretchable tissue covering the soft palate, vestibules, ventral side of the tongue, and internal cheeks/lips.
Cervical: The area of the tooth nearest the gumline. The cervical diameter is narrower than the middle or occlusal/incisal diameters.
Embrasure: A triangular space between two contacting tooth surfaces, located between the contact point and the gingiva.
Interdental Papilla: The gingiva (gum tissue) located within the space between teeth.
Gingiva (Gums): Masticatory mucosal tissue covering the alveolar processes and surrounding the cervix of each tooth. * Free Gingiva: Also called unattached gingiva. * Attached Gingiva: Stippled, dense tissue firmly bound to underlying tissue.
Fissure: Deep crevices located between adjoining cusps.
Pit: The intersection point where two fissures cross.
Cusp: A convex elevation on the occlusal surface of a tooth that ends in a rounded or conical surface.
Mamelon: A ruffle-like enamel protrusion found on the anterior incisal surfaces of primary teeth.
Contours, Contacts, and Embrasures: Collectively these features maintain tooth position and protect tissues during chewing.
Cingulum: A raised, rounded enamel protrusion on the cervical third of the lingual surface of maxillary incisors.
Fossa: A wide, shallow, concave depression on the lingual surface of anterior teeth.
Groove: A small, linear, concave depression on a tooth surface.
Diastema: A space between two teeth that are not in contact.
Coronal: Pertaining to the crown of the tooth.
Anatomical Crown: The portion of the tooth covered entirely by enamel.
Clinical Crown: The portion of the tooth visible within the mouth.

Periodontium and Supporting Structures

Periodontium: Structures that surround, support, and attach to teeth to keep them functional in the jaw. Its soft tissues include the periodontal ligament and the gingival unit (lining and masticatory mucosa). The cementum of the tooth attaches to the periodontal ligament, which in turn attaches to the alveolar process.
Alveolar Process: The trabeculated (spongy) bone in the maxillae and mandible that supports teeth in their sockets.
Lamina Dura: The dense, compact bone lining the alveolar sockets.
Periodontal Ligament: Acts as a shock absorber; it attaches the tooth cementum to the lamina dura.
Radicular: Pertaining to the root of the tooth.
Periapical: Surrounding the tip (apex) of the tooth root.

Tooth Tissues and Specialized Structures

Enamel: The translucent covering of the crown; it is the hardest tissue in the human body.
Cementum: The calcified covering of the root. The periodontal ligament attaches to its exterior.
Dentin: The bulk of the tooth, surrounding the pulp. It is covered by enamel on the crown and cementum on the root. It is harder than bone but softer than enamel and is capable of growth and repair.
Pulp: Vital tissue containing blood vessels and nerve fibers. * Pulp Horns: The highest portion of the pulp cavity, following the upward projections of the cusp tips.
Apical Foramen: The natural opening at the root apex into the pulpal tissue.
Sulcus: The space between the tooth surface and the free gingiva.
Epithelial Attachment: The attachment at the base of the gingival crevice that connects the cementum to the periodontal ligament.

Dental Terminology: Orientation and Science

Vestibule: The space between the teeth and the inner mucosal lining of the tissue extending from the mucogingival junction to the cheeks and lips.
Occlusal: The chewing surface of posterior teeth.
Incisal: The biting surface of anterior teeth.
Mesial: The proximal surface closest to the facial midline.
Distal: The proximal surface furthest from the facial midline.
Lingual: The surface facing the tongue.
Buccal: The surface of a posterior tooth facing the cheek.
Labial: The surface of an anterior tooth facing the lips.
Facial: A general term for any outward-facing tooth surface.
Cervix: The neck of the tooth where enamel meets the gums.
Embryology: The study of prenatal development.
Histology: The study of tissue structure and function on a microscopic level.
Morphology: The study of the form and shape of structures like teeth.
Embryonic Period: Occurs from the $2^{nd}$ to the $8^{th}$ week of prenatal development. This is the most critical time; maternal dental infections during any gestational period can harm the fetus.
Structural Units of the Body: Organized from smallest to largest: Cells, Tissues, Organs, Body Systems.
Body Systems: There are $11$ systems: skeletal, muscular, cardiovascular, lymphatic/immune, nervous, respiratory, digestive, urinary, integumentary, endocrine, and reproductive.

Physiological Systems and Craniofacial Anatomy

Arteries: Large vessels carrying blood away from the heart.
Veins: Small vessels carrying blood to the heart for oxygenation.
Osteoblasts: Cells that form bone.
Osteoclasts: Cells that resorb bone.
Resorption: The process of eliminating existing bone or hard tissue.
Tonsils: Lymphatic tissue masses forming a protective ring in the nose and throat. * Nasopharyngeal Tonsils: In the nasopharynx. * Palatine Tonsils: In the oropharynx, visible in the mouth. * Lingual Tonsils: Located on the back of the tongue.
Salivary Glands: Three pairs producing saliva: * Parotid: Largest gland; uses Stensen’s duct. * Sublingual: Uses sublingual duct. * Submandibular: Uses Wharton’s duct.
Saliva: Composed of $99\%$ water and $1\%$ salts/acids/enzymes. It contains amylase, an enzyme that initiates digestion by breaking down food.
Cranial Bones ( $8$ ): Temporal ( $2$ ), Parietal ( $2$ ), Ethmoid, Frontal, Occipital, Sphenoid.
Facial Bones ( $14$ ): Zygomatic ( $2$ ), Maxilla ( $2$ ), Palatine ( $2$ ), Nasal ( $2$ ), Lacrimal ( $2$ ), Vomer, Mandible, Inferior conchae ( $2$ ).
Mandible: The longest, strongest, and only movable bone of the face. * Parts: Ramus (upright posterior portion), mental foramen, mandibular foramen, mental protuberance, retromolar area.
Temporomandibular Joint (TMJ): Formed by the articulation between the temporal bone’s glenoid fossa and the mandible.
Sinus: Hollow spaces in bone; there are four pairs of paranasal sinuses.
Palate: * Hard Palate: The anterior $\frac{2}{3}$ portion. * Soft Palate: The posterior $\frac{1}{3}$ portion. Touching this activates the gag reflex, a protective mechanism preventing aspiration into the lungs.
Vermilion Border: The outline of the lips.
Frenum: A band of connective tissue in the oral cavity.
Muscle Types: * Striated: Voluntary/skeletal muscle. * Smooth: Involuntary/visceral muscle.

Mastication and Muscles

Mastication: The act of chewing.
Muscles of Mastication: * Zygomatic: Laughing/frowning muscle; moves mouth angles. * Orbicularis Oris: Puckers and closes lips. * Mentalis: Pushes up lower lip and raises chin. * Masseter: The strongest muscle; closes jaws. * Temporal: The largest muscle of mastication; closes jaws. * Buccinator: Compresses cheeks/holds food. * Internal Pterygoid: Closes jaws. * External Pterygoid: Opens and protrudes the jaw.

Tooth Development and Clinical Examination

Eruption: Tooth movement into functional position. First to erupt: primary mandibular central incisors. Last: permanent third molars.
Exfoliation: Natural shedding of primary teeth.
Centric Occlusion: Maximal stable, comfortable contact between maxillary and mandibular teeth.
Functional Occlusion: Contact during biting/chewing.
Palpation: Using hands to feel texture, size, and consistency.
Percussion: Tapping the tooth with a mirror handle parallel to the long axis to determine sensitivity.
Exudate: Pus; localized fluid at an infection site.
Stains: * Extrinsic: Created externally (e.g., coffee, tobacco). * Intrinsic: Created internally (e.g., tetracycline).

Preventive Dentistry and Oral Hygiene

Preventive Dentistry: Goal is to help patients keep natural teeth for life by treating decay early.
Coronal Polishing: Abrasion of enamel using a low-speed handpiece and prophy cup with various grits (coarse, medium, fine).
Ultrasonic Scaler: Machine using water jets to remove supragingival calculus and bioburden.
Dentifrices: Products containing fluoride to combat decay. NaF (Sodium Fluoride) is the common active ingredient.
Pumice: Abrasive agent used in professional cleaning.
Xerostomia: Dry mouth; lack of saliva facilitates caries.
Caries: Tooth decay/cavities. Caused by Mutans streptococci and Lactobacilli bacteria interacting with a susceptible tooth and fermentable carbohydrates (sugar, starch, fruit, dairy). It is the most common disease of early childhood.
Plaque: Soft, sticky deposit of food and bacteria attached via the pellicle. Must be removed every $12$ - $24$ hours.
Bass Method: Toothbrushing technique using circular motions at a $45^{\circ}$ angle into the sulcus.
Calculus (Tartar): Hardened plaque; can only be removed with scalers or curettes.
Essential Minerals: Calcium, Phosphorus, and Fluoride combat decay. Demineralization is the start of caries.
Fluoride Methods: * Systemic: Through fluoridated drinking water. * Topical: Direct application via treatments (varnish) or dentifrices (toothpaste/rinses).
Prophylaxis: Professional cleaning (removing stains/polishing) at $3$ - $6$ month intervals; primary treatment for gingivitis.
Periodontal Pocket: A sulcus measurement of $\ge 4\,mm$ , indicating attachment loss.
Supragingival: Above the gumline.
Subgingival: Below the gumline.

Periodontal and Restorative Conditions

Abscess: Localized infection/pus. A periapical abscess is at the root tip.
Necrosis: Tissue death (e.g., necrotic pulp).
Periodontal Disease: Leading cause of tooth loss in adults. Two forms: Gingivitis (reversible) and Periodontitis (irreversible; shows bone loss/flattening of the alveolar crest on radiographs).
Alveolar Crest: The highest point of the alveolar ridge.
Cavosurface Margin: Where restorative material meets natural tooth structure.
Axial Wall: Internal surface of a prep in the same vertical direction as the pulp (long axis).
Dovetail: Fanned-out portion of a prep for mechanical retention.
Debridement: Removal of diseased/necrotic tissue.
Microleakage: Space allowing fluid/bacteria between restoration and tooth due to different expansion/contraction rates.
Galvanic Shock: Sensation when unlike metals contact in the mouth.
Properties of Materials: * Esthetics: Appearance/beauty. * Stress: Internal resistance to external force. * Ductility: Ability to withstand tensile (pulling) stress. * Malleability: Ability to withstand compressive (pushing) stress.

Restorative Materials and Procedures

Direct Restorations: Applied, carved, and finished in the operatory.
Indirect Restorations: Created in a lab from a dentist’s prescription (e.g., porcelain). Fixed restorations require a thin cement lining on internal walls.
Alloy: Mixture of two or more metals.
Amalgam: Mercury mixed with silver, tin, zinc, and copper. Used for Class I, II, and V restorations. * Mercury: Hazardous liquid metal. Ratio in amalgam is one drop mercury to one pellet alloy. * Amalgam Procedure: Rinse/dry, place liner/base (CaOH2/ZPC), varnish, insert, condense, carve/burnish. Check bite with articulating paper. No eating for $4$ - $6$ hours; sets in $24$ hours; polish at $48$ hours with tin oxide.
Composite: Tooth-colored direct material for Class III, IV, and V. * Composite Procedure: Shade selection, prep with diamond/carbide burs, isolate with dam/cotton, etch, prime/bond, air-thin, light cure in layers, finish/polish.
Crown Prep Procedure: Alginate impressions, prep tooth, gingival retraction cord, final impression (elastomeric), temp crown (ZOE), lab Rx. Delivery $2$ weeks later with ZPC.
Crown Types: * FGC: Full Gold Crown. * PFM: Porcelain Fused to Metal. * SSC: Stainless Steel Crown (primary teeth or temporary). * Porcelain Jacket: Full veneer crowns for anterior only.

Dental Cements and Chemistry

ZPC (Zinc Phosphate): "Fleck’s." Permanent cement for gold crowns; insulating base ( $Type\,2$ ) providing thermal protection.
IRM: Strongest temporary material; provisional filling or cement.
Acid Etch: Phosphoric acid solution ( $H_3PO_4$ ). Roughens surface for micromechanical retention.
Calcium Hydroxide: "Dycal." Medicated liner; encourages secondary/tertiary dentin growth. Placed under bases.
ZOE (Zinc Oxide Eugenol): "TempBond." Sedative base; soothes pulpitis. Contains clove oil (Eugenol). Cannot be used under composite.
Varnish: Seals dentin tubules; cannot be used under composite.
Polycarboxylate: "Durelon." Permanent cement for metal to enamel.
Glass Ionomer: Permanent cement; contains fluoride.
Exothermic Reaction: Chemical reaction giving off heat. Counteracted by using a glass slab at $68^{\circ}$ to $72^{\circ}\,F$ .
Polymerization: Chemical setting/hardening.

Impression Materials and Mechanics

Alginate: Irreversible hydrocolloid for preliminary impressions. Use water at $68^{\circ}$ to $72^{\circ}\,F$ . * Type 1 (Fast-set): $1$ to $2$ minutes. * Type 2 (Normal): $2$ to $4.5$ minutes.
Gypsum: Mineral used for study models (Plaster of Paris/Dental Stone).
Forces: * Tensile: Pulls and stretches. * Compressive: Pushes together. * Shearing: Slices apart.
Prosthodontics: * Denture: Replaces all teeth in an arch. * Partial: Replaces some teeth. * Bridge: Multiple units. Abutment is the anchor; Pontic is the artificial floating tooth. * Inlay/Onlay: Cast restorations; onlays cover $2+$ cusps.

G.V. Black’s Classification of Caries

Class I: Pits/fissures (occlusal posterior, lingual/buccal grooves, lingual fossae maxillary anterior).
Class II: Proximal surfaces of posterior teeth ( $2+$ surfaces).
Class III: Proximal surfaces of anterior teeth.
Class IV: Proximal surfaces plus incisal edge of anterior teeth.
Class V: Gingival/cervical third of any tooth.
Class VI: Cusp tips or incisal edges; wear and tear.

Radiology and Clinical Set-up

Bitewing: Shows crowns and interproximal areas.
Periapical: Shows entire tooth (apex to cusp) and bone.
FMX: Full series; $18$ x-rays for adults, $8$ - $12$ for primary.
Wash Field: Using HVE to remove fluids/debris.
HVE (High-Volume Evacuator): Assistant holds in right hand for right-handed dentist.
Rubber Dam: $6" \times 6"$ latex/vinyl sheet. Clamp on anchor tooth (most distal). Sizes: 5 (anchor), 4 (molar), 3 (premolar), 2 (maxillary anterior), 1 (mandibular anterior).
Ergonomics: * Static Zone: $12$ - $2\,o'clock$ . * Assistant's Zone: $2$ - $4\,o'clock$ . * Transfer Zone: $4$ - $7\,o'clock$ . * Operator's Zone: $7$ - $12\,o'clock$ .

Handpieces and Infection Control

Highspeed: $40,000$ to $450,000\,RPM$ . Uses friction-grip (FG) burs.
Low speed: $10,000$ to $30,000\,RPM$ . Uses right-angle (RA) or latch-type burs.
Disinfection: Benchmark effectiveness is the ability to kill Tuberculosis (tuberculocidal).
Sterilization Methods: Steam (Autoclave), Chemical (Chemiclave), Dry Heat, Flash (Stat-im).
Biologic Monitoring: Spore testing; the only way to confirm sterilization. Recommended weekly by CDC, ADA, and OSAP.

Anesthesia and Vital Signs

Trigeminal Nerve: $5^{th}$ cranial nerve; pairs of ophthalmic, maxillary, and mandibular branches.
Needles: Blue ( $1"$ long) for infiltration; Red/Yellow ( $1.5"$ long) for blocks.
Epinephrine: Vasoconstrictor in anesthetic; contraindicated for heart conditions/high BP.
Nitrous Oxide ( $N_2O$ ): Blue tank; requires a scavenger system.
Oxygen ( $O_2$ ): Green tank.
Pulse: Normal adult $60$ - $100\,bpm$ (radial artery).
Respiration: Normal adult $10$ - $20\,bpm$ .
Blood Pressure: Normal adult < 120/80\,mmHg.
Temperature: Normal resting oral $97.6^{\circ}$ to $99^{\circ}\,F$ .
CPR Sequence: CAB (Chest compressions, Airway, Breathing).

Ethics, Law, and Safety

Principles of Ethics: Autonomy, Do No Harm, Promotion of Well-being, Justice/Fairness.
Dental Board of California (DBC): Interprets the DPA. LTA program counts for $10$ months experience; requires $5$ additional months to reach $1280$ hours for RDA state boards.
Occupational Exposure: * Category I: Direct contact with blood/saliva (DDS, RDH, DA). * Category II: Occasional exposure (Front office). * Category III: No routine exposure.