DN15 Flashcards
1
Q
THREE MAIN ORAL DISEASES OF CONCERN:
A
DENTAL CARIES - the bacterial infection of the mineralised tissues of the tooth
GINGIVITIS - the inflammation of the gingival tissues at the neck of the tooth
PERIODONTITIS - the inflammation of the supporting structures of the tooth
2
Q
DENTAL CARIES:
A
dental caries is a bacterial disease of the mineralised tissues of the tooth, where the strong crystal structure found in both enamel and dentine is DEMINERALISED (dissolved) by the actions of acids
3
Q
RELEVENT FACTORS IN THE DEVELOPMENT OF DENTAL CARIES?
A
- the presence of certain types of BACTERIA
- CARBOHYDRATE FOODS
- the production of WEAK ORGANIC ACIDS by these bacteria
- adequate TIME OR FREQUENCY for the acids to attack the tooth
4
Q
STREPTOCOCCUS MUTANS
A
the main MICROORGANISM which initiates the process of caries
5
Q
CARIOGENIC FOODS:
A
CARBOHYDRATES can be turned into into acid by bacteria and thereby cause caries, so they are described as cariogenic foods becuase they are capable of causing caries
6
Q
INTRINSIC SUGARS:
A
found naturally in foods, such as FRUCTOSE in fruits
7
Q
MILK EXTRINSIC SUGARS:
A
especially lactose considered harmless
8
Q
EXAMPLES OF ADDED SUGAR FOODS THAT CAN CAUSE CARIES:
A
- cake, biscuits, jam and sweets
- breakfast cereals
- pastry, desserts, canned fruit, syrups and ice cream
- soft drinks
- hot beverages sweetened with sugar
9
Q
DEFINITION OF STAGNATION AREAS
A
parts of a tooth most prone to caries are those where food tends to collect easily during normal chewing movements and plaque bacteria can flourish
10
Q
COMMON STAGNATION AREA’S:
A
occlusal fissures and the spaces between the mesial and distal surfaces of adjoining teeth (the interproximal areas, or contact points) are the commonest stagnation areas.
11
Q
PROCESS OF CAVITY FORMATION:
A
- white spots
- enamel decay
- dentine decay
- involvement of the pulp
- abscess formation
- tooth loss
12
Q
IRREVERSIBLE PULPITIS
A
pulpitis (inflammation of the pulp occurs when caries extends through the dentine to reach the pulp. pulpitis may be acute or chronic. it has many causes, apart from caries, but almost always ends in pulp death.
13
Q
ACUTE ALVEOLAR ABSCESS:
A
- extremely painful condition
- the affected tooth becomes loose and very tender to the slightest pressure
- there is continual throbbing pain and the surrounding gums is red and swollen
- frequently, inflammatory swlling invloves the whole side of the face and the patient may have a raised body tempreture (pyrexia)
- looseness is caused by swelling of the periodontal ligament
- acute alveolar abscess may show all of the cardinal signs of acute inflammation:
- pain
- swelling
- redness
- heat
- loss of function
- raised body tempreture
14
Q
WHAT COMPONENTS DO SALIVA CONTAIN?
A
- WATER, as a transport agent for all of the other constituents
- INORGANIC IONS AND MINERALS, such as calcium ions and phosphate
- PTYALIN, a digestive enzyme that acts on carbohydrates
- ANTIBODIES, as part of the defensive immune system, as known as IMMUNOGLOBULINS
- LEUCOCYTES, or white blood cells, also part of the body’s defence system
15
Q
FUNCTION INORGANIC IONS AND MINERALS IN SALIVA
A
are released as required to act as a BUFFERING AGENTS to help control the pH of the oral environment, by neutralising the organic acids produced by bacteria
a high inorganic ion/mineral content produces thick, stringy saliva which gives the teeth good protection against caries, but allows DENTAL CALCULUS (tartar to form easily in large amounts
a low inorganic ion/mineral content produces watery saliva, which offers little protection to the teeth against caries, but prevents large amounts of calculus from forming
16
Q
FUNCTION ON WATER IN SALIVA
A
water forms the carrying agent for the other salivary constituents and allows self-cleansing of the oral enviroment to occur by DISLODGING FOOD DEBRIS from the teeth before being swallowed
the water also Moistens the food bolus and the soft tissues, allowing SWALLOWING (deglutition) and SPEECH to occur
it also DISSOLVES food particles, so that the sensation of TASTE is produced
17
Q
ANTIBODIES AND LEUCOCYTES IN SALIVA:
A
the antibodies and leucocytes help to protect and defend the oral environment from infection by microorganisms
18
Q
THE REDUCED SALIVARY FLOW CONDITION:
A
the condition of reduced salivary flow is called EXROSTOMIA or DRYMOUTH. causes of this are as follows:
- low fluid intake over a period of time, or even dehydration
- some autoimmune disorders, especially sjorgen’s syndrome, which specifically affects the salivary glands and the lacrimal glands of the eyes, which produce tears
- several routinely prescribed drugs, including DIURETICS, ANTIDEPRESSANTS, and BETA-BLOCKERS
19
Q
CONSEQUENCES OF REDUCED SALIVARY FLOW OF THE PATIENT:
A
- reduced self-cleansing allows more food debris to accumulate around the teeth, increasing plaque production and the likelihood of caries and periodontal disease developing
- it will also allow food debris to stagnate in the mouth, causing HALITOSIS
- reduced buffering of the oral environment allows longer and more frequent acid attacks, increasing the likelhood of caries developing
- poor lubrication of the oral soft tissues makes speech and swallowing more difficult
- reduced amounts of water in the saliva affect the sensation of taste
- reduced flow and amounts of saliva in the mouth will make the retention of dentures more difficult
20
Q
DIAGNOSIS OF CARIES:
A
the dentist has various methods available for detecting smaller carious lesions, as follows:
- close visible inspection under magnification, with the help of a bright examination light and a mouth mirror to reflect the light onto less visible areas
- the use of various blunt dental probes to detect and stickiness in suspicious area - particularly using a sickle probe or right-angle probe for occlusal surfaces, and a special double-ended briault probe for interproximal areas
- transillumination of anterior teeth, using the curing light to shine through their contact points, and viewing from behind the mouth mirror to detect any shadowing.
- caries dyes wiped into prepared cavities to stain any residual bacteria to make them visible and allow their removal
- periodical horizontal bitewing radiographs to detect interproximal caries in posterior teeth
- these can also detect recurrent caries beneath exsisting restorations, as well as early caries beneath occlusal fissures
21
Q
PERIODONTAL DISEASE
A
periodontal disease is the oral disease that affects the supporting structures of the teeth. theses supporting structures are the gingivae, the periodontal ligament and the alveolar bone.
there is a relatively uncommon, but specific, type of periodontal disease that begins in childhood rather than adults and this is called juvenile periodontitis.
22
Q
STAGES OF PERIODONTAL DISEASE:
A
the earliest stage of periodontal disease is CHRONIC GINGIVITIS which is chronic inflammation involving the gingivae alone. this can occur in a localised area and affect only a few teeth or it can occur generally and affect the majority of the dentititon. once present and if allowed to continue, the chronic inflammation spreads deep into the underlying cementum and periodontal ligament, and eventually to the alveolar bone. these structures are gradually destroyed and the teeth become very loose as their supporting tissues are lost. the name given to this late stage of the disease is CHRONIC PERIODONTITIS. there is no dividing lne between the two stages, and untreated chronic gingivitis usually progresses into chronic periodontitis.
23
Q
CAUSES OF PERIODONTAL DISEASE
A
periodontal disease is a bacterial infection of the supporting structures of the tooth, caused by an initial accumilation of BACTERIAL PLAQUE at the gingival margin of the tooth.
24
Q
HOW DOES PLAQUE TURN INTO CALCULUS?
A
plaque can be removed by adequate tooth brushing, but in the absence of this counter-measure, it thickens as its microbial population fluorishes amid a permanent food supply. toxic by-products of the plaque microorganisms then act as a continual source of bacterial irritation, which causes chronic inflammation of the gum margin (chronic gingivitis). the plaque extends above and below the gum margin, and wherever it is present CALCULUS (tartar) formation can occur.
25
WHAT IS CALCULUS?
calculus is the hard rock-like deposit commonly seen on the lingual surface of lower insicors. two factors are necessary for its formation: PLAQUE and SALIVA. the interaction between these two factors allow mineralisation to occur within the plaque and produce a deposition of calculus, which may be defined as solidified plaque. it is most easily seen opposite the orifices of salivary gland ducts. this visible calculus on the crowns of the teeth has a yellowish colour and is called SUPRAGINGIVAL CALCULUS as it forms above the gum margin. however, it also occurs beneath the gum margin on all teeth and in that situation it is known as SUBGINGINGIVAL CALCULUS. this is harder and darker than supragingival calculus and its surface is covered with a layer of the soft microbial plaque from which it was formed.
26
ADDITIIONAL REASONS FOR PLAQUE FORMATION WHICH ARE NOT DUE TO POOR ORAL HYGIENE:
sometime plaque formation is caused by imperfect dentistry, these are known as IATROGENIC FACTORS AND INCLUDE:
- fillings or crowns that have an overhanging edge at their cervical margin
- fillings or crowns with loose contact points that allow food trapping to occur
- ill-fitting or poorly designed partial dentures
27
PERIODONTAL TISSUES IN HEALTH:
to be able to recognise the presence of periodontal disease, the appearance of these tissues in health must first be identified and anatomically is as follows:
- the tooth sits in its socket within the alveolar bone
- it is attached to the bone by the fibres of the periodontal ligament, which run from the cementum of the root into the alveolar bone
- other periodontal ligament fibres run from the alveolar bone crest to the neck of the tooth, and from the neck of the tooth into the gingival papilla
- the bone and the periodontal ligament are covered by the mucous membrane of the gingiva, which lines the alveolar ridges
- the gingiva is attached directly to the neck of the tooth itself at a specialised site called the JUNCTIONAL EPITHELIUM
- in health, a gingival crevice of up to 3mm deep runs as a "gutter" around each tooth, the deepest part of which is the attachment of the junctional epithelium
- looking at the tissues in the mouth, then, the gingiva is generally pink in colour with the gingival crevice no deeper than 3 mm
- the interdental papillae between the teeth are sharp, with a knife-edge appearance
- no bleeding occurs when the gingival crevice is gently probed during the dental examination
- subgingivally, the periodontal ligament and alveolar bone are intact - this will only be visible on a radiograph
if plaque is allowed to accumulate around the gingival margins of the teeth, the gingiva will become inflamed and the first stage of periodontal disease, GINGIVITIS, will develop. when time is a generalised condition affecting the oral cavity as a whole becuase of poor oral hygiene, it is called CHRONIC GINGIVITIS
28
CHRONIC GINGIVITIS :
The sequence of events that occur microscopically and that lead to chronic gingivitis are as follows:
- the bacteria within the plaque at the gingival margins use food debris to nourish themselves, so that the colony grows in size
- they produce TOXINS as a by-product during their own food digestion
- these toxins tend to accumulate in the gingival crevice, as they are not removed by oral hygiene measures or washed away by the normal cleansing action of saliva
- the gingiva in direct contact with the toxins become irritated, causing inflammation and the early signs of CHRONIC GINGIVITIS
- the inflamed gingiva becomes red in colour, and the swelling associated with the inflammation creates FALSE POCKETS around the necks of the teeth - there appears to be a deepening of the gingival crevice but this is due to the swelling only, not to a loss of attachment berween the junctional epithelium and the tooth; hence the name "false"
- the presence of these pockets allows more plaque to accumulate as cleansing becomes even more difficult, and the plaque now begins to extend below the gingival margin
- in this environment, there is little oxygen available for the initial bacteria to use, and the plaque becomes colonised by specialised bacteria that are able to survive without oxygen - these are called ANAEROBIC BACTERIA
- examples of these are ACTINOMYCES and PORPHYROMONAS GINGIVALIS, both of which are bacteria specifically associated with periodontal disease
- in the meantime, the inorganic ions within saliva are incorporated into the structure of the plaque so that it hardens and mineralises as DENTAL CALCULUS develops
- calculus forming above the gingival margin is called SUPRAGINGIVAL CALCULUS and is YELLOW in colour
- that forming below the gingival margin is called SUBGINGIVAL CALCULUS and is BROWN in colour, due to the blood pigments incorporated into it from the bleeding gingival tissues
- the rough surface of the calculus irritates the gingiva further and allows more plaque to develop on it
- the rough calculus and the irritation of the bacterial toxins cause painless MICRO-ULCERS to develop within the gingiva, so that they BLEED on touch or gentle probing
- the red swollen gingiva and the presence of bleeding of probing are the classic visible signs of CHRONIC GINGIVITIS
29
CHRONIC PERIODONTITIS
if chronic gingivitis is not treated, microbial poisons from the plaque soak through the micro-ulcer in the gingival crevice and penetrate the depper tissues. these poisons gradually destroy the periodontal ligament and alveolar bone, and while this is progressing, the gingival pocket deepens, thus further aggravating the condition. whereas the false pockets of chronic gingivitis are caused by inflammatory swelling of the gum only, in chronic periodontitis they are TRUE POCKETS caused by the destruction of the base of the gingival crevice and its attachment to the tooth. in other words, the attachment between the junctional epithelium and the tooth surface is lost. at the same time, the gingival margin may recede, exosing the root of the tooth to view. this GINGIVAL RECESSION is commonly known as being "long in the tooth". if no treatment is provided, so much none is lost that the teeth eventually become too loose to be of any functional value.
30
CHRONIC PERIODONTITIS - THE SEQUENCE OF EVENTS THAT OCCUR:
- the bacterial toxins build up within the false pockets and eventually begin soaking into the gingival tissue itself, through the micro-ulcerated areas
- here, they gradually destroy the periodontal ligament and the attahcment of the tooth to its supporting tissues, and a TRUE POCKET forms
- the loss of attachment gradually moves down the tooth root, creating deeper pockets that allow even more plaque and calculus to develop within them
- the toxins eventually begin attacking the alveolar bone itself, destroying the walls of the tooth socket so that the tooth becomes loose
- this tooth loosening is often the first indication the patient has of the presence of their disease, as it is usually painless and often takes several years to reach this point
- periodontitis also tends to have intermittent active phases where much tissue destruction occurs, interspersed with quiet phases of little bacterial activity, so in a sporadic fashion rather than occuring as a gradually progressive condition
This decription of periodontal disease follows a slowly progressive but painless course of several years, but during that time pus and microorganisms in the pockets cause bad breath (HALITOSIS) and may affect the patients general health
31
CHRONIC PERIODONTITIS - SOME AGGRAVATING FACTORS ARE:
- smoking
- unbalanced or excessive masticatory stress
- natural hormonal changes such as puberty and pregnancy
- open lip posture (such as occurs during mouth breathing) which dries out the oral cavity and prevents the normal cleanasing action of saliva to occur
32
CHRONIC PERIODONTITIS - CAN BE MADE WORSE WITH CERTAIN MEDICAL CONDITIONS AND DRUGS, SUCH AS:
- diabetes, acquired immune defiency syndrome (AIDS), lukemia, and other blood disorders or diseases where resistance to infection is poor - these patients are referred to as being IMMUNE-COMPROMISED
- epilepsy treated with phenytoin (Epanutin)
- Vitamin C defiency
- Treatment with immunosuppressant drugs such as ciclosporin and cytotoxin agents
33
DIAGNOSIS OF PERIODONTAL DISEASE:
The diagnosis of periodontal disease is based on the medical history, appearance and recession of the gums, depth of gingival pockets, amount of bone loss, tooth mobility and the distribution of plaque.
34
MEDICAL HISTORY FOR PERIODONTAL DISEASE:
A regularly updated medical history is an essential feature of all patient's recors, whatever their reason for attendance or the treatment required. as far as periodontal disease is concerned, the dentist will be particularly interested in:
- Past and present illnesses
- Drugs prescribed
- Hormonal changes
- Smoking habits
Relevent illnesses are those where resistance to infection is low, such as:
- diabetes, leukaemia and other blood disorders
- vitamin deficiencies
- AIDS
- Treatment with immunosuppressant drugs, e.g. ciclosporin (Sandimmun), used for some types of cancer and for organ transplant patients
Certain drugs can cause a sever, non-inflammatory enlargement of the gums called GINGIVAL HYPERPLASIA, which requires surgical correction. such drugs include:
- Phenytoin (Epanutin), used to control epilepsy
- Nifedipine (Adalat), used to control angina pectoris and reduce high blood pressure
- Ciclosporin, used to prevent organ rejection after transplant
35
SIGNS OF EARLY ONSET CHRONIC GINGIVITIS ARE AS FOLLOWS:
- the gingiva bleed on brushing, or on gentle probing during the dental examination
- They appear visibly red and swollen
- Plaque is visible at the gingival margins of the teeth or can be shown using disclosing solution
- the patient has halitosis
36
SIGNS OF CHRONIC PERIODONTITIS:
- periodontal probing detect pockets > 3mm
- both supragingival and subgingival calculus will be present
- some teeth may be mobile
- radiographs will show destruction of the alveolar bone in long standing-cases, with associated deep periodontal pockets present
37
PREVENTION AND MANAGEMENT OF DENTAL DISEASES:
caries occurs due to a combination of certain types of bacteria being present within dental plaque that use NMES to produce acids that cause enamel demineralisation. there are therefore three main areas of caries prevention available to the patient and the dental team:
- CONTROL THE BUILD-UP OF BACTERIAL PLAQUE - practise its regular removal by using good oral hygiene techniques
- INCREASE THE TOOTH RESISTANCE TO ACID ATTACK - by incorparating fluoride into enamel structure
- MODIFICATION OF THE DIET - to include fewer cariogenic foods and drinks and to reduce their frequency of intake
The prevention of periodontal disease van be achieved in most patients, whereas it can only be controlled in others:
- CONTROL THE BUILD-UP OF BACTERIAL PLAQUE - practise its regular removal by using good oral hygiene techniques
- MODIFY THE CONTRIBUTORY FACTORS - by giving advice on smoking cessation, for instance
- CONTROL THE HOST RESPONSE - in patients predisposed to periodontal problems, by more frequent dental attendance for monitoring and evaluation, and intervention where necessary
38
CONTROL OF BACTERIAL PLAQUE:
plaque can be easily and regularly removed by the patient at home by carrying out a regular combination of the following oral hygiene techniques on a daily basis:
- TOOTH BRUSHING, using a recommended TOOTPASTE
- INTERDENTAL CLEANING
- USING SUITABLE MOUTHWASHES
39
CONTROL OF BACTERIAL PLAQUE -
| TOOTH BRUSHING
general advice on tooth brushing techniques is as follows:
- toothbrushes with a small head and multi-tufted medium nylon bristles are probally the most effective for the vast majority of patients
- good-quality, electrical toothbrushes take the need for consistently food manual techniques away from the patient, and are more likely to achieve a prolonged high standards of oral hygiene
- the brush is rinsed to wet the bristles and a portion of the recommended toothpaste added
- each dental arch is divided into three sections: left and right sides, and front
- side sections are subdivided into buccal, lingual and occlusal surfaces; front sections into the labial and lingual
- when instructing patients, these areas should be reffered to in terms the patient can understand - such as the 'cheek side', 'tounge side', 'lip side' and so on
- this amount to eight groups of surfaces in each jaw, and at least 5 seconds should be spent on each group
- egg timers or similar devices are useful here so that the patient obtains an idea of how long the recommended '2 minute' brushing cycle is
- patients should be encouraged to develop their own start and end points within the oral cavity and then follow this systematically at each brushing session, so that a methodical routine is developed
- each area is brushed in turn and the mouth is then cleared by spitting out the toothpaste and oral debris
- the patient should be instructed NOT to rinse the mouth out, as this will remove the residual toothpaste and prevent its chemical contituents from containing to act in the mouth - this is particularly important advice with fluoridated toothpastes
40
CONTROL OF BACTERIAL PLAQUE -
| TOOTHPASTES
- over 95% of toothpastes available in this country contain FLUORIDE, as sodium monofluorophosphate and sodium fluoride at 1000 parts per million (ppm)
- HIGH-FLUORIDE toothpastes containing between 2800 and 5000ppm, for use by adult patients with an exsisting high caries rate or an excessive risk to developing caries
- several other toothpastes containing ingredients specifically to slow down CALCULUS formation
- many now contain the substance triclosan combined with zinc, which acts as an ANTISEPTIC PLAQUE SUPPRESSANT
- some toothpastes are specifically formulated to help RELIEVE SENSITIVITY, and containg ingredients such as stannous fluoride
- others are advertised as 'WHITENING TOOTHPASTES' and act to remove surface tooth staining by the use of abrasives or, more recently, by the use of biological enzyme systems
- more recent developments have included toothoastes designed to help protect teeth against ACID EROSION
41
CONTROL OF BACTERIAL PLAQUE -
| INTERDENTAL
the mesial and distal contact areas between adjoining teeth are more prone to developing caries and periodontal disease. to clean the interdental areas adequately, several oral health adis are available to assist patients with removal of plaque that has formed here, as follows:
DENTAL FLOSS and DENTAL TAPE are thread-like aids that are widely used by many patients to achieve interdental palque removal; however, correct usage depends to some extent on the patient's manual dexterity and on rreceiving sound oral health instruction
'FLOSSETTE-STYLE' handles hold the length of floss in palc for the patient so that they can floss with one hand, therefore making the procedure less cumbersome, especially for posterior teeth where access is difficult for the majority of patients
INTERDENTAL BRUSHES are of typical 'bottle-brush' design and are able to clean in spaced interdental areas, as well as around the individual brackets of fixed orthodontic appliances
WOOD STICKS are also available to dislodge solid pieces of food debris from interproximal areas, as well as to massage the gingivae here; however their use should be restricted to competent adults whenever possible, as they can easily be stuck into the gum and cause problems if used incorrectly or by an inexperienced patient
The aim of all these interdental aids is to dislodfe food particles and accumulated plaque from the interdental areas of the teeth, so that the debris can be swallowed or removed from the oral cavity.
42
MOUTHWASHES:
- general-use mouthwashes contain various ingredients to promote good oral hygiene, including:
- SODIUM FLUORIDE - to provide topical fluoride application to the teeth
- TRICLOSAN - a chemical that suppresses the formation of plaque in the oral cavity
- others are specialised for use on sensitive teeth
- some are used specifically in the presence of oral soft tissue inflammation as a first aid measure, or after oral surgery, and contain HYDROGEN PEROXIDE which helps to elimate anaerobic bacteria
- specialised mouthwashes are also available for patients suffering from both acute and chronic periodontal infections, and contain chlorhexidine, an ANTISEPTIC PLAQUE SUPPRESSANT
43
OTHER METHODS OF PLAQUE REMOVAL:
after eating a meal, tooth brushing may not always be possible until several hours later, by which time plaque will have formed and possibly started to cause damage. obvious examples are after eating lunch at school or at work, while out for a meal in the evening.
in these situations, loose food debris can be removed by using sugar-free chewing gum or finishing the meal with a DETERGENT FOOD and-or piece of cheese. detergent foods are raw, firm, firbrous fuits or vegetables, such as apples, pears, carrots and celery.
44
INCREASE TOOTH RESISTANCE TO ACID ATTACK:
FLUORIDE is the single most important chemical coumpound that is of use in the battle against dental caries. it occurs naturally in the water in some areas and is added artificially to water supplies in other areas during the process of water fluoridation as an oral health measure to aid in the reduction of caries incidence.
45
TOPICAL FLUORIDES:
these are administrated externally to the tooth surface, by either the patient or the dental team, to provide a continual source of fluoride directly onto the enamel
46
TOPICAL FLUORIDES - FOR USE BY PATIENT:
- FLUORIDE TOOTHPASTES containing the current recommended dose for all patients of 1000ppm, and up to 50000ppm for use by adults at high risk of developing caries
- a minimum of twice-daily brushing is advised to achieve maximum benefits
- patients should be advised NOT TO RINSE OUT after brushing, as it washes the fluoride away and is therefore less effective
- FLUORIDE MOUTHWASHES for regular use by those with a high caries risk and those undergoing orthodontic treatment
- DENTAL FLOSS and tape impregenated with fluoride, for delievery directly to the interproximal areas
