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91 Cards in this Set

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Dental Caries

Is a disease of the hard (calcified) tissues of the tooth (enamel, dentin, cementum), also referred to as a cavity or tooth decay.

It is caused by specific types of bacteria which create acidsthat can destroy the tooth structure.

Decay is characterized by decalcification (demineralization) of the mineral content of these tissues.

Periodontal Debridement

Removal of all debris (plaque biofilm, stain and calculus) from the crowns and roots of the teeth.

Periodontal Disease

Includes a variety of inflammatory and degenerative diseases involving the supporting tissues of the teeth.


Pertains to the prevention of disease


-Root planing


-Coronal polishing

-Topical fluoride application


Is a procedure in whichcalculus (hard dental deposits), dental plaque and some extrinsic (outer) stains are scraped (cleaned) off the teeth with specific dental instruments called scalers and curettes.

Root Planing

Is a procedure done to smooth the tooth root to remove any remaining calculus and bacterial toxins


Gingival curettage is a surgical procedure designed to remove the soft tissue lining of the periodontal pocket with dental instruments(curettes) to remove the diseased tissue.

The theory behind the use of gingival curettage in the treatment of periodontal disease is that it removes the diseased tissue, reducing the inflamed tissue allowing the tissue to heal and reattach to the tooth

Coronal polishing

Coronal polishing is a cosmetic procedure used to remove extrinsic (outer) stains from the enamel surfaces of the teeth.

non-essential cosmetic procedure

Selective polishing minimizes enamel being worn away by the abrasives in the polishing paste that is used to remove stain

Dental flossing

Is the best way to ensure that bacterial plaque is removed from between the teeth. Neither the polishing procedurenor a scaling instrument can completely clean the tight contact areas between the teeth.

Topical fluoride application

Once the removal of the deposits off the teeth is completed, an optional fluoride treatment can be provided for the patient to help prevent tooth decay and sensitivity

Oral Prophylaxis procedures that DA's can do

coronal polishing and fluoride treatments

3 types of dental deposit

1. Soft Deposits

2. Hard Deposits

3. Stains

Soft Deposits

1. Acquired pellicle

2. Dental plaque (which is also often referred to as dental biofilm)

3. Materia alba

4. Food debris

Acquired Pellicle

-Appearance- Thin film, clear, translucent, sometimes stained

-Composition- Acellular, Salivary glycoproteins

-Attachment- Selective adsorption of protein components from the saliva

-Significance- Protective: provides a barrier against acids. Dental Plaque biofilm formation: provided a surface for attachment and colonization. Attachment of calculus: one mode

-Removal- Coronal polish

Dental Plaque/ Dental Biofilm

-Appearance- Small amounts are not visibleunless disclosed, as it accumulates it becomes visible and ranges in color from gray-yellow, the surface has a rough “furry” appearance

-Composition- A dense non-mineralized, complex mass of colonies in a gel-like intermicrobial matrix. Contains many types of micro-organisms. (Organic and inorganic solids 20% and water 80%)

-Attachment- To acquired pellicle (therefore can alsoadhere to the teeth, calculus and dental restorations

-Significance- Associated with the development of dental decay, periodontal disease and the formation of calculus

-Removal- Toothbrushing, flossing and coronal polishing

Plaque formation

1- Formation of acquired pellicle

2- Bacterial multiplication & colonization

3- Biofilm growth and maturation (matrix formation)

Materia alba

-Appearance- Bulky, loosely connected mass that looks like cottage cheese. It is white or cream colored and opaque

-Composition- Living and dead organisms, fooddebris, desquamated epithelial cells, disintegrating leukocytes, proteins from saliva

-Attachment- Loose attachment

-Significance- Surface bacteria in contact with the gingiva contribute to gingival inflammation; often see demineralization under

-Removal- Vigorous rinsing, waterspray, toothbrushing and flossing

Food debris

-Appearance- Particles of food

-Composition- Particles of food

-Attachment- Loose, wedges in and around teeth, restoration and appliances

-Significance- Provides a source of nutrients for oral bacteria, which may contribute to acid formation and therefore decay

-Removal- Vigorous rinsing, toothbrushing and flossing

Hard Deposits


Dental calculus is a hard-calcified deposit that forms on and adheres firmly to teeth, restorations and dental appliances.

Calculus is an important etiologic factor in periodontal diseases because it is a bacterial agent. Thus, a reason to control bacterial plaque formation is to prevent calculus formation.

Allowing the presence of calculus provides a surface for new acquired pellicle, bacterial plaque and additional calculus to form. Thus begins a cycle of supra-gingival and sub-gingival calculus accumulation, eventual periodontal soft tissue inflammation, and progressive periodontal disease

Calculus and how it forms from bacterial biofilm

Pellicle formation

-The pellicle forms on the tooth surface by selective absorption of the protein components from the saliva into the hydroxyapatite.

Plaque biofilm formation and colonization

-As microorganisms attach themselves to the pellicle they begin to Colonize. These colonies form in layers as the bacteria multiply and grow over time...the colonies enlarge and form a continuous mass


-As the biofilm matures mineralization starts to occur, usually 1-2 days after initial biofilm formation. Mineralization consists of crystals forming in the intermicrobial matrix and on the surface of the bacteria and within the bacteria. This process is not fully understood. Calcium and phosphates from the saliva/sulcular fluid become incorporated into the matrix and calcify

dental plaque biofilm VS. calculus

Dental plaque biofilm is the sticky film of bacterial colonies that constantly form on the teeth. If dental plaque biofilm is not removed from the teeth through regular tooth brushing and flossing, it hardens to create calculus. Calculus cannot be removed by a toothbrush; it can only be removed by scaling or root planning

The effect of calculus on the health of the periodontal tissue and on the general health of the oral cavity

Calculus is significant in the progression of inflammatory periodontal disease ( the disease causing bacteria are held in the rough surface and perpetuate the inflamed state)

Calculus Removal

DA's can't remove calculus but can get the

instruments ready.

-Sickle Scalers

-Universal Curette

-Area Specific Curettes

-Periodontal Files

-Powered Hygiene Instruments - Sonic and ultrasonic


Discoloration of the teeth occurs when pigmented materials:

-are deposited onthe surfaces of the teeth


-are incorporated into the tissues of the teeth



When the stain is confined to the tooth surface and is capable of being removed by rinsing, toothbrushing, simple use of abrasives, scaling, and/or coronal polishing



When the stain has permeated into the tooth tissue and has become a part of it, making removal difficult or impossibleand cannot be removed by polishing



Originating outside the body



Produced by the body

significance of stains

Generally, any damaging or detrimental effect on teeth or gingiva isrelated to bacterial plaque and/or calculus in which the stain is embedded.By themselves stains do not cause dental disease.

Thick bulky stains can be a source of irritation if they are located adjacent to the gingival margin

Exogenous Extrinsic Stains

Stains that originate outside the tooth and is caused by environmental agents; they appear on the exterior of a tooth and can be removed.

Endogenous Intrinsic Stains

Stain that has permeated or become incorporated into tooth tissue and has become part of it, making removal difficult or impossible. Thus, these stains occur within the tooth. Intrinsic endogenous stains cannot be removed by any procedure of the oral prophylaxis. They present no problem because by themselves they don’t weaken tooth structure or make the teeth more susceptible to disease

Exogenous Intrinsic Stains

Thecause of the stain is from an outside source, not from within the toothhowever, the stain becomes incorporated into the tooth

Brown stain

(Exogenous Extrinsic)

-Appearance- grainy. Tones of brown

-Distribution- plaque retention areas. Along gingival margin

-Age- All

-Cause- Stannous fluoride. Chlorhexidine rinse

Yellow stain

(Exogenous Extrinsic)

-Appearance- Dull yellow. Discoloured plaque.

-Distribution- Can cover complete tooth or along gingival margin

-Age- All ages

-Cause- Food or drink pigments. Poor oral hygiene

Green stain

(Exogenous Extrinsic)

-Appearance- light green to dark green. Embedded bacterial plaque.

-Distribution- facial surfaces. Mx ant 1/3

-Age- mainly children

-Cause-Chromogenic bacteria

Black line stain

(Exogenous Extrinsic)

-Appearance- continuous line along gingival margin. Rough (needs to be scaled before polish)

-Distribution- facial and lingual. Gingival contour

-Age- mainly children but can be in all

-Cause- Chromogenic bacteria. Ferric sulphate ions from water.

Tobacco stain

(Exogenous Extrinsic)

-Appearance- Light brown to dark black

-Distribution- any surface. Lingual surfaces. Any enamel irregularities.

-Age- Smokers. (cigarette, pipes, cigars) Chewing tobacco

-Cause- Tar products

Orange/Red stain

(Exogenous Extrinsic)

-Appearance- Orange and red shades

-Distribution- cervical third. Usually anterior

-Age- rare. usually children

-Cause- Chromogenic bacteria

Metallic stain

(Exogenous Extrinsic)

-Appearance- Industrial dust.

-Copper (green)

-Brass (green)

-Iron (brown)

-Nickel (green)


-Iron and magnese

-Distribution- Cervical third. Usually anteriors

-Age- Industrial workers. Taking above drugs

-Cause- Inhaled dust. Ingesting water with metallic content. Liquid drugs.

Tetracycline Stains

Tetracycline is an antibiotic that kills many types of bacteria in the body.

This drug can cause many side affects including gray colored or gray-striped teeth.The gray stains caused by Tetracycline penetrate deep into the tooth enamel and into the dentine below the enamel.

Tetracycline teeth stains develop on permanent teeth while they are still forming under the gum line.

Dental Caries Disease Process

Dental caries is a multifactorial disease that results from the interaction between the dental plaque, the environment (e.g., diet, saliva composition and flow rate, fluoride exposure), and the tooth structure

The disease process involves a shift in balance between protective factors that aid in tooth remineralization (i.e., gaining of minerals back into the tooth) and destructive factors that aid in tooth demineralization (i.e., loss of minerals from the tooth), resulting in demineralization over time

Essential Criteria for Dental Caries

1.Susceptible Tooth- Any tooth that has erupted into the oral cavity

2. Acidogenic Microorganisms- Acidogenic bacteria are bacteria that produce an acid from fermentable carbohydrates. There are numerous acidogenic microorganisms found in dental plaque. (ex. S.mutans, lactobacilli)

3. Cariogenic Food Source (Fermentable Carbohydrates)- Fermentable carbohydrates are sugars that are easily fermented and breakdown in the oral cavity into simple sugars(glucose, fructose, maltose and lactose)

Other contributing factors of dental caries

-Time- 15-20 mins. until acid

-pH- When thepH of the oral cavity is lower than5.5 the acids can begin to demineralize enamel.

-Dextrans and Levans- Are sticky tenacious sugar like compounds that contribute to the thickness and stickiness of dental plaque.

-Patient Education- Daily removal of dental plaque from both the teeth and oral tissue along with a reduction in cariogenic food sources are essential elements required to reduce the incidence of dental diseases (both dental caries and periodontal disease).

Location of Dental Caries

1. Pit and fissure caries: primarily on the occlusal surfaces, the buccal and lingual grooves of posterior teeth and the lingual pits of maxillary incisors

2. Smooth surface caries: occurs on intact enamel other than pits and fissures

3. Root surface caries: any surface on the root

4. Secondary or recurrent caries; occurs on the tooth surrounding a restoration

Early Childhood Caries (ECC)

ECC isan infectious, transmissible, diet reliant disease that can start right after the eruption of primary teethand may progress very rapidly.

Some of the potential consequences of ECC are acute and chronic pain; interference withthe child’s eating, sleeping and proper growth; toothloss and malocclusion; increased expensesfor dental care throughout life; and compromise of general health

Dental Erosion

Dental erosion is the progressive irreversible loss of dental hard tissue that is chemically etched away from the tooth surface by acids. Erosion isoften associated with other forms of tooth wear such as abrasion and attrition (from aggressive tooth brushingand grinding of teeth, for example)


-assists in the removal of sugar from the mouth (physical protection)

-neutralizes and buffers acids in bacterial plaque (chemical protection)

-maintains tooth minerals by making available calcium (Ca2+) and phosphate (PO43-) ions (chemical protection)

-contains antibacterial properties (antibacterialprotection).

Saliva Viscosity (resistance to flow)

Thin, watery, and copious saliva

-Fewer materials to contribute to the formation of bacterial plaque.

-Assistance in loosening or washing away food debris.

Thick, mucinous saliva

-added materials to form or compose plaque

-hangs onto the tooth surface more easily

-traps debris

Saliva Quantity (amount)

A decrease in the flow of saliva (Xerostomiaor Hyposalivation) create an increased predisposition (tendency) to cavities. Any condition that causes Xerostomia may results in the development of rampant decay

Increasing Saliva Flow

Chewing Gums

Saliva Substitutes- aerosol or a liquid that is squirted into the mouth. The products coat the mucosa and teeth to help keep them moist, reduce enamel solubility and remineralize the tooth surface


-Xylitol cannot be metabolized by cariogenic microorganism and thus does not reduce the pH of the plaque. If the pH does not fall, demineralization cannot occur.

-Xylitol suppresses the size of colonies of S. mutans. It alters cell wall formation andreduces bacterial colonization

-Xylitol affects the quality of plaque making it less adhesive and less likely to form

-These effects depend upon a regulated use pattern; in other words, for maximum benefit, the xylitol containing products must be consumed frequently

-Xylitol is more expensive to produce than sugar.

What increases an individual’s risk for dental caries?

-tooth position and morphology


-oral hygiene



-socioeconomic status


-high counts of cariogenic bacteria

Tooth Position and Morphology

Tooth morphology = shape and contour of teeth

-Malpositioned or crooked teethcanincrease the tendency for retention of food debris and soft deposit.

Occlusal and proximal surfaces are the most caries susceptiblesurfaces. Why?

-occlusal surfaces have pits, fissures and grooves which represent surface irregularities that are more difficult to reach with the bristle ends of a tooth brush

-Proximal surfaces, when they contact each other, are harder to access during cleaning


Teeth exposed to fluoride both before eruption and after eruption are more resistant to decay.


1.promotion of remineralization and inhibition of demineralization of early carious lesions

2.inhibition of glycolysis, the process by which cariogenic bacteria metabolize fermentable carbohydrates


1.some reduction in enamel solubility in acid by pre-eruptive incorporation of fluoride into the hydroxyapatitecrystal(main mineral component of the tooth)

Genetics and decay

Inheritance of specific tooth morphology conducive to decay; i.e. malformed teeth and deep grooves, can occur.

Diet and decay

It is the sugar and fermentable carbohydrate (CHO)component of the diet that is associated with the formation of caries

-Fats and Proteins do not cause decay. They are considered to be cariostatic

-Each time we snack, acid is produced for at least 15-20 minutes. Acid production changes the pH of the oral cavity for about 2 hours. Each time acid is produced, there is the opportunity for an “acid attack” or demineralization to occur.


-gingiva- providesa tissue seal around the cervical portion of the tooth.

-periodontal ligament- suspends and maintains the tooth in its socket

-cementum- anchors the ends of the periodontal ligament fibers to the tooth (maintaining the tooth in the socket). Protects the dentin of the root.

-alveolar bone- surrounds and supports the roots of the tooth

Periodontal Disease

Periodontal disease is an infectious disease process that involves the inflammation of the structures of the periodontium. Periodontal disease is one of the most common diseases of man even though we know how toprevent the development of periodontal diseases.

Etiology of Periodontal Disease

As you know, dental plaque is a bacterial biofilm which can causechronic gingivitis and periodontitis. Periodontal disease is viewed asa host-microbial interaction in which both host and bacterial factors determine the outcome

Periodontal Disease Process

Dental Plaque (Biofilm)

-the presence of bacteria is necessary for periodontal disease to occur

Host Inflammatory and Immune Response

-the waythe body reacts to bacteria is known as the host response

-it is the interaction between the bacteria and the host response to these bacteria that is responsible for the tissue destruction


Gingivitis is the mildest form of periodontal disease. Itis a bacterial infection that is confined to the gingiva. It causes the gums to become red, swollen, and bleed easily.

Gingivitis is often caused by inadequate oral hygiene.

The damage that occurs during gingivitis is reversible with professional dental care and good oral home care


Periodontitis is a bacterial infection of all the parts of the periodontium including the gingiva, periodontal ligament, bone and cementum. The damage thatoccurs in periodontitis isirreversible. Untreated gingivitis can progress to periodontitis.

With time, plaque can spread and grow sub-gingivally. Toxins produced by the bacteria in plaque irritate the gingival tissues. The toxins stimulate a chronic inflammatory response in which the body in essence turns on itself, and the tissues and bone that support the teeth are broken down and destroyed. The gingivadetachfrom the teeth, forming periodontal pockets (spaces between the teeth and gums) that become infected. As the disease progresses, the pockets deepen and more gingivaltissue and bone are destroyed. Often, this destructive process has very mild symptoms. Eventually, teeth can become loose and may have to be removed.

Aggressive periodontitis

occurs in patients who are otherwise clinically healthy. Common features includerapid attachment loss and bone destruction and familial aggregation

Chronic periodontitis

results in inflammation within the supporting tissues of the teeth, progressive attachment and bone loss. This is the most frequently occurring form of periodontitis and is characterized by pocket formation and/or recession of the gingiva. It is prevalent in adults, but can occur at any age. Progression of attachment loss usually occurs slowly, but periods of rapid progression can occur.

Necrotizing periodontal disease

is an infection characterized by necrosis of gingival tissues, periodontal ligament and alveolar bone. These lesions are most commonly observed in individuals with systemic conditions such as HIV infection, malnutrition and immunosuppression

Systemic factors

are conditions, habits or diseases that increase an individual’s susceptibility to periodontal infection

1.Tobacco use

2.Diabetes mellitus


4.Psychosocial stress

5.Acquired Immunodeficiency Syndrome (AIDS)

6.Systemic medications

7.Hormone alterations


9.Nutrition Deficiencies


Local Contributing Factors

are oral conditions that increase an individual’s susceptibility to periodontal disease

Plaque retention

-Dental calculus

-Tooth morphology

-Tooth surface irregularities

-Untreated tooth decay

Pathogenicity of plaque

-Undisturbed plaque growth (poor oral hygiene)

Direct damage to the periodontium

-Trauma from occlusion

-Food impaction

-Parafunctional habits(clenching and bruxism): can exert excessive force onthe teeth and the periodontium.

-Faulty restorations and appliances

-Mouth breathing

-Tongue thrust: places abnormal lateral forces on the teeth which may damage the periodontium

healthy periodontium

he tooth is surrounded by the gingivalsulcus. The junctional epithelium (JE) forms the base of the sulcus by attaching to the enamel of the crown near the cemento-enamel junction (CEJ). The depth of a healthy sulcus is from 1–3 mm.

periodontal pocket

A periodontal pocket is the result of the destruction of the alveolar bone and periodontal

ligament fibers that support the tooth in the alveolar socket. A pocket is a diseased gingival sulcus

Pocket depths

The calibrated periodontal probe is used to locate, assess and measure sulcus and pocket depths. A pocket is measured fromthe base of the pocket or diseased sulcusto the gingival margin.

Periodontal Probe

A probe is a periodontal instrument that is marked in millimeters (mm) increments and is used to evaluate the health of periodontal tissues

Function of Periodontal Probes

The periodontal probe is used to obtain information about the health status of the periodontium.Probes are used tomeasure sulcus and pocket depths to:

-Determine sulcus topography

-Identify gingival bleeding

-Measure the size of an oral lesion

-Aid in the detection of calculus and identification of root morphology

probing depth measurements

Probing depths are measured and recorded on a periodontal chart. This becomes a permanent part of the patient’s chart and is a legal document.

Six Sites per Tooth:







One Reading per Site

The deepest reading obtained in that site is recorded

Full Millimeter Measurements

Probe depths are recorded to the nearest full millimeter. Round measurements to the next higher full measurement (e.g. 3.5 mm would be recorded as 4 mm)

Probing Dental Implants

The major disadvantage of titanium is that it scratches easily. As a result, the use of traditional metal probes is contraindicated for use around dental implants. Plastic probes are safe to use on all types of implants, without damaging the implant surface

The probing of a dental implant should be avoided until post-operative healing is complete. This is determined by the dentist

probe depths can be used to monitor peri-implant health

Periodontal Screening and Recording (PSR)

The PSR method is a form of periodontal assessment used to determine:

-the periodontal health status of a patient

-if the patient requires a more comprehensive periodontal assessment

Only six scores are recorded, instead of the 192 scores (in a full probing examination)

How Does PSR Work?

The sites examined on each tooth are:







Instead of a detailed charting of the probe readings at each siteas in full mouth probing, only the deepest pocket reading of each sextant is charted using specific PSR codes

The PSR system specially-designed probe

The probe has markings at 3.5, 5.5, 8.5 and 11.5 mm. The probe is colour-coded from the 3.5 to the 5.5 mm markings. The tip of the probe isa 0.5 mm ball, which reduces the risk of over measurement and aids in the detection of calculus, overhangs and other irregularities.

How the PSR Scoring System Works

As you are probing, continuously monitor the colour-coded reference mark on the PSR probe. At each site probed, the colour-coded reference mark will be:
-completely visible (less than 3.5 mm)
-partially visible (3.5-5.5 mm)
-not visible at all (g...

As you are probing, continuously monitor the colour-coded reference mark on the PSR probe. At each site probed, the colour-coded reference mark will be:

-completely visible (less than 3.5 mm)

-partially visible (3.5-5.5 mm)

-not visible at all (greater than 5.5 mm)


an area of bone loss at this branching point of a tooth root

an area of bone loss at this branching point of a tooth root

Signs of periodontal disease

-bleeding upon probing

-pocket depth greater than 5 mm

-furcation involvement

-persistent tooth mobility

-purulent discharge

-mucogingival problem

-occlusal/orthodontic disturbances

-positive microbial tests

four main benefits of the PSR system

1. It improves patient care (monitors the patient’s periodontal health status).

2. It saves time, replacing the need for full-mouth exams in healthy patients.

3. It is an educational tool.

4. Allows the dentist to identify patients who require referral to a specialist.

Where is the col area of the gingiva?

The col area is the innermost part of the interdental papilla. It is the depression found between the lingual and vestibular papilla that conforms to the proximal contact area.

The col area is the innermost part of the interdental papilla. It is the depression found between the lingual and vestibular papilla that conforms to the proximal contact area.

disclosing agent

liquid concentrate or tablet containing an ingredient that stains deposits and debris present on the teeth so that it can be easily seen

Common Types of Disclosing Agents

Erythrosin Dye- most commonly used agent. It stains bacterial plaque red and acquired pellicle a pale pink colour

Fluorescein- is a dye that can be appliedto the teeth without obvious staining. A special ultra violet light is used to make this agent visible

Two-tone- disclosing agents which stain thicker plaque, blue and thinner plaque, red

Purposes for Using Disclosing Agents

-providing individualized instruction in self-care in the location of soft deposits and the techniques for removal

-the patient in evaluating his/her skills plaque removal

-periodic evaluation by the dental assistant

-to determine the need for revisions of the plaque-control procedures

-to study the long term effects over successive maintenance appointments

-completing a plaque control record

-collecting research data in order to gain new information about the incidence and formation of deposits on the teeth

Plaque Indices

A plaque indexis simply an expression of clinical observations in numerical values. It is used to describe the status of an individual or a group with respect to a condition being measured

Method for Using the Plaque Control Record (PCR)

First, all teeth surfaces (*except the occlusal surfaces) are stained with a disclosing solution.

After a short rinse, each tooth surface is observed using an explorer and mirror. Only the gingival third of the tooth at the dentogingival junction is evaluated.

Every tooth is divided into 4 sections: mesial, distal, facial, lingual, at the anatomic line angles.

Draw a vertical line through any missing teeth

If a soft deposit is visible, the corresponding surface is marked on the PCR by placing a “dot” or “dash”or “colour”on the appropriate area.

index or score

calculated by dividing the number of plaque containing surfaces by the total number of available surfaces (total # of teeth x 4 surfaces)

# plaque containing surfaces

--------------------------------------- X100%=Plaque score

total # of available surfaces

(total # of teeth x 4 surfaces)

<10% is a good score

Occlusal surfaces are not included.

Simplified Oral Hygiene Index(OHI-S)

Each of the four surfaces of the teeth (buccal, lingual, mesial and distal) is given a score from 0-3. The scores from the four areas of the tooth are added and divided by four in order to give the plaque index for the tooth

Each of the four surfaces of the teeth (buccal, lingual, mesial and distal) is given a score from 0-3. The scores from the four areas of the tooth are added and divided by four in order to give the plaque index for the tooth