NDAEB Theory Exam key terms

A way of working where the dentist and assistant pass instruments and materials in a planned order, using preset positions and transfer zones so treatment is faster, safer, and less tiring for both operators.

The area over the patient's chest where the assistant passes and receives instruments, kept clear of the patient's face and the dentist's field of view so movements stay safe and predictable.

Standard clock positions around the dental chair, usually 7 to 12 o'clock for the dentist and 2 to 4 o'clock for the assistant, chosen to give good vision and ergonomic reach.

A large suction tip held by the assistant to remove saliva, water, and debris during treatment, keeping the field dry and reducing airborne particles and aerosols.

A small, low-volume suction device placed in the floor of the mouth to keep the area free of pooled saliva and water during procedures where the main suction is used elsewhere.

Keeping a tooth or area dry and free of saliva, blood, and moisture during treatment so materials such as sealants, bonding agents, and restorations set and stick properly.

Placing processed films or digital images into a holder or viewer in the correct order and orientation so the images can be read with the right and left sides correctly identified.

An image showing the crowns of upper and lower teeth together with the alveolar crest, used mainly to detect interproximal caries and to check bone levels.

An image that shows the whole tooth, from crown to root tip, plus the surrounding bone, used to find infection, cysts, or root problems and to check root anatomy.

The top edge of the bone that surrounds and supports the tooth roots; it is visible on bitewing images and is used to judge bone loss from periodontal disease.

How dark or light an area appears on an image; dense structures such as enamel and metal block X-rays and look light, while air and soft tissue look dark.

The range of dark-to-light shades in an image; good contrast makes it easier to tell enamel from dentin and to spot small areas of decay.

Shielding worn by the patient during X-ray exposure to protect the body and the thyroid gland from unnecessary radiation while the needed images are taken.

A soft, sticky film of bacteria that forms on teeth and gums, especially near the gumline and between teeth, and causes both caries and gum inflammation if not removed regularly.

Hardened mineralized plaque that sticks firmly to teeth, usually near the gumline, and cannot be removed by brushing or flossing; it must be removed by professional scaling.

A dye, often in tablet or liquid form, that stains plaque so the patient can see where brushing and flossing were missed and where technique needs improvement.

A brushing method in which the bristles are angled toward the gumline and moved in small circles or a gentle jiggle, cleaning the sulcus and the sides of teeth effectively.

Cleaning between teeth with floss, interdental brushes, or other aids, where a toothbrush cannot reach, to remove plaque that causes interproximal decay and gum disease.

The shallow groove between the tooth surface and the free gum margin; it is the area where plaque is most likely to collect and where the bristles should be aimed.

Able to cause tooth decay; the word is used for foods, drinks, and bacteria that promote acid production and loss of tooth mineral.

Sugars and cooked starches that mouth bacteria break down into acid; the more often they are eaten, the longer teeth stay under acid attack.

The drop in mouth pH that happens after eating sugar, when bacteria make acid that attacks enamel; frequent snacks mean frequent acid challenges.

Loss of mineral from enamel or dentin caused by acid; early on it looks like a white, chalky area that can still be repaired if the acid attacks stop.

The return of minerals such as calcium and phosphate into weakened enamel, helped by saliva and fluoride, which can repair early damage before a cavity forms.

A stretchy latex or non-latex sheet placed over the tooth or teeth being treated to keep the area dry, protect the patient from swallowing debris, and reduce contamination.

A metal ring with jaws that grips the tooth, usually the most posterior one, to hold the dam securely in place during treatment.

A hand tool with a sharp point and a rotating head that makes clean holes of selected sizes in the dam so it fits closely around the teeth.

Removing soft plaque and stain from the visible tooth surfaces with a rotating rubber cup or brush and polishing paste, used only when there is no hard deposit left.

An abrasive paste, often pumice-based, used with a rubber cup to clean and polish tooth crowns; it is chosen in a grit suited to the amount of stain present.

A concentrated fluoride coating painted onto teeth that sets on contact with saliva, used to strengthen enamel and reduce caries, especially in high-risk patients.

Custom or stock trays filled with fluoride gel or foam and placed over the teeth for a set time so the agent reaches all surfaces, after which the patient must not rinse or eat for a while.

A plaster or stone copy of the patient's teeth and arches made from an impression, used to record the bite, plan treatment, and compare changes over time.

A record of the teeth and surrounding tissues made with a soft, fast-setting seaweed-based material in a tray, used to pour study models or make appliances.

A rigid or plastic frame that holds impression material and is sized to the patient's arch so the material can be carried to the teeth and set around them.

A thin strip placed around a prepared tooth to rebuild the missing wall of the cavity so restorative material can be packed and shaped while it sets.

A small wooden or plastic triangle pushed between teeth to hold a matrix band tightly against the tooth, separate the teeth slightly, and protect the adjacent tooth.

A metal holder with a tightening screw that grips a matrix band and holds it firmly around the tooth during placement of a restoration.

A thin coating placed on the floor of a prepared cavity, when the pulp is not involved, to protect the pulp and seal the dentin before the restorative material is added.

An acid gel, usually phosphoric acid, applied to enamel or dentin for a set time to create a rough surface that lets bonding material grip the tooth.

A resin liquid painted onto etched tooth surfaces and cured with light to form a strong link between the tooth and the restorative material or sealant.

The layer of tooth under the enamel that is softer and more porous; it contains tiny tubules that can carry sensation and allow fluids to reach the pulp.

A resin coating placed in the deep grooves of back teeth to block food and bacteria from settling there and to help prevent decay on chewing surfaces.

Bleaching a living tooth, usually with a peroxide gel in a custom tray, to lighten stains in the enamel and dentin while the tooth keeps its nerve and blood supply.

A clear, closely fitting tray made from a study model of the patient's teeth that holds whitening gel against the tooth surfaces and keeps it away from the gums.

A common, usually temporary side effect of whitening, felt as a brief sharp twinge to cold or air, often managed by using less gel, shorter wear time, or a desensitizing product.