PERIODONTOLOGY Flashcards
What are the two types of mechanical scalers used?
Ultrasonic - operating above 20kHz (kilohertz)
Sonic (or Air) - operating between 5-10kHz
What is the function of the mechanical scalers?
Both types of instrument use a water spray at the working tip. the water acts to cool the working tip (the tip becomes heated in use) and to flush debris away from the site of operation
Describe features of an ultrasonic
They operate at a frequency of between 20,000 and 30,000 vibrations per second (20-30 kHz)
They are NOT air driven but powered by an electric current
Far more effective and patient friendly than sonic scalers
Describe the Magnetostrictive type of ultrasonic
Magnetostrictive (think cavitron) - a stack of ferromagnetic metal is acted upon by electrical windings in the handpiece, which produce an alterning MAGNETIC movement. When the stack is magnetised it contracts and this movement is transferred to the working tip and tooth surface!
describe the pizoelectric type of ultrasonic
this is when small currents of electricity are used to alter the diamonds of quartz crystals on the working tip which produces vibration effect
Describe the MECHANICAL action of the ultrasonic
- MECHANICAL - mixture of back and forth circulatory movements of the working tip mechanically abrades and chips away at the calculus deposits on the tooth surface.
describe the CAVITATIONAL effect that ultrasonics provide
the coolant water contains minute air bubbles which are expanded by the energy at the vibrating tip causing them to implode and release shock waves removing calculus and plaque biofilm
air bubbles also release oxygen which kills anaerobic bacteria within the periodontal pockets. v effective and vital use.
Describe the acoustic streaming action of an USS
All mechanical scalers set up vigorous movements of water around their tips known as acoustic streaming
helps to remove some of the tooth surface deposits and disrupt plaque colonies.
when would we consider using a mechanical scaler? (5)
supra/sub deposits
pre during and post sub ging PMPR
cavitational effect only
stain removal
removal of excess cement/amalgam ledges
What is the main potential hazard of using a mechanical scaler
From the clinicians POV, hazard is from the AEROSOL generated by the combined action of water spray and working tip. Most important that the clinician wears full PPE whilst carrying out this procedure.
When may we not use a mechanical scaler? (8)
- porcelain jacket crowns can be fractured -best to avoid crowns when using USS here
- hypersensitivity, decalcification, implants
- pacemaker
- COPD
- very old/young
- anxious patients
- hypersensitivity - exposed dentine
- decalcification - IRREVERSIBLE damage will occur
Describe the interference that an USS could have on a pacemaker.
Pacemakers and ICDs are sensitive to strong electromagnetic signals that may temporarily interfere with function.
Most devices are now designed with safeguards that include electronic FILTERS or SHIELDS that insulate the presence of electromagnetic interference.
What is the AIM of perio treatment
To reduce pathogens in the sub-gingival biofilm to a level which is conducive to healing.
What is dental calculus?
Hardened plaque by saliva
Acts as a rough surface which encourages further plaque accumulation (plaque retentive factor).
This is why removal of calculus is an essential element of perio treatment. it is very adherent to tooth surfaces and can only be removed by dental professional
Features of supra-gingival calculus (3)
Colour - yellow/brown
Heaviest opposite openings of salivary ducts (lingual lower incisors, buccal upper molars)
Fairly hard and brittle
features of sub-gingival calculus(5)
attached to root surfaces
colour - dark green/black
within perio pockets and not directly visible unless tissue shrinkage has ocurred
occurs throughout the mouth
very hard and can be difficult to remove with instruments
What instrument can we use to detect sub-ging calc
cross calculus probe to detect on root surfaces
Describe some features of the cross-calculus probe
double ended “hooked” instrument
place on tooth with the lower shank parallel to the long axis of tooth
with the hooked side facing the tooth, gently place instrument into the pocket
apply gentle pressure against the root surface an slowly with draw the probe out of the pocket. ledges of sub calc will be detected on root surface.
List some advantages of powered scalers (6)
- simple and effective - less time than hand scaling
- can be used supra/sub
- no instrument sharpening required
- water spray provides constant lavage and irrigation
- useful in tight pockets as less tissue distortion
- useful for furcations
What is reattachment of the periodontium?
- describes reunion of root and connective tissue seperated by incision or injury
- re attachment of epithelium in perio disease does NOT occur, therefore, reattachment is not a term we use when we refer to PERIODONTAL HEALING.
What is NEW attachment
- describes union of connective tissue with previously pathogenically ALTERED root surface.
Describe the effects of mechanical plaque control on the microflora (subgingival PMPR) (4)
- there is a marked decrease in the total number of organisms (regardless of type)
- the proportion of gram-ve anaerobic (main cause of perio disease) organisms is greatly reduced
- residual flora is gram positive aerobic
- these changes in sub-gingival plaque flora are partly due to a reduction in plaque thickness - less MOTILE bacteria
Following RSD treatment, what do we typically see…
- there is an initial ACUTE inflammatory reaction as a result of trauma - begins to subside after 24-48 hours
- over following week post rsd we should see decrease in vasodilation, GCF, PMN’S, ulceration of pocket
over time, what can we then see post sub-ging PMPR in healing of the perio tissues (3)
- fibroblasts migrate to the site and collagen fibres are laid down. elasticity in epithelium return. (FIBROBLASTS PRODUCE COLLAGEN)
-limited re-modelling of the alveolar crest takes place (bone doesn’t regrow in perio treatment! )
-pocket epithelium begins to attach to root surface (attaches via hemi-desmosomes)
Describe how the pocket epithelium begins to attach to the root surface (5)
- New attachment is known as the long junctional epithelium (JE). It attaches by hemi-desmosomes to make a desmosome.
- The junctional epithelium migrates apically resulting in a loss of the PDL
- no gingival fibres involved. gingivae attaches directly to the root surfaces. LONG JUNCTIONAL EPITHELIUM.
- healing is via the basement of a membrane.
- THIS IS A MUCH MORE FRAGILE ATTACHMENT this is why we cant probe…
What happens during NEW ATTACHMENT POST sub-ging PMPR
there is formation of the LONG JUNCTIONAL EPITHELIUM
this long epithelium results in gradual closure of a pocket and may continue for months after treatment
think of the junctional epithelium acting like a zip/zips up pockets
What will we see CLINICALLY during the healing process of sub ging pmpr to see if tx has been a success or not? (5)
- Initially, a reduction in redness and swelling as the inflammation subsides
- BOP is reduced as inflammation resolves
- Ulcers in pocket epithelium heal
- Gingivae become increasingly pink and firm as connective tissue matures
- As inflammation subsides there is SHRINKAGE of the tissues (gingival shrinkage)
What are some cons (disadvantages) to gingival shrinkage as a post op symptom from subging pmpr
- can expose dentine and lead to dentine hypersensitivity
- pts not aesthetically pleased sometimes
What is gingival shrinkage due to?
due to a tightening in the gingival CUFF
What is released during healing of sub ging pmpr
CYTOKINES are released during healing which have a regulatory function !
proliferation and healing of the ulcerated pocket is stimulated by cytokines, which in turn attract fibroblasts. (FIBROBLASTS PRODUCE COLLAGEN)
What are cytokines in perio healing
a group of proteins that are released to trigger a certain amount of processes eg attracting fibroblasts, neutrophils etc.
what is regeneration in perio healing?
this means the attachment of PDL cells and fibres to new cementum formation and coronal regrowth of alveolar bone (IDEAL AIM IN PERIO TREATMENT IS TO PROMOTE COMPLETE PERIO REGENERATION)
Why to bone cells and periodontal ligament cells NOT regenerate?
Because they are much more COMPLEX cells than simple epithelial cells. they take a lot more time to reproduce and are never given a chance to regenerate.
list some of the periodontal surgery techniques used to PROMOTE NEW ATTACHMENT
bone grafting
conditioning of root surfaces
use of membranes
Describe what guided tissue regeneration is (3)
- currently most successful method of new attachment formation
- uses mechanical barrier to eliminate epithelium from wound to determine which cells repopulate wound
- promotes population by cells derived from PDL and bone
List some of the future prospects for managing perio disease (4)
- prevention of the disease
- diagnostic testing
- chemotherapy
- new attachment (guided tissue regeneration)
what is RECESSION (3)
- a seemingly inflammation-free clinical condition characterised by apical retreat of the periodontium
- THE ID PAPILLA OFTEN REMAIN AT THE NORMAL LEVEL
- teeth are never lost due to true recession
recession can be localised or generalised
2 terms to do with gingival recession:
what do we mean by FENESTRATION?
this is a WINDOW in the bone, usually found on the buccal aspect in patients
what do we mean by DEHISCNECE
this is a LACK of bone, commonly where a tooth is proclined. happens commonly on lower anterior area
list some of the different reasons for recession (5)
- chronic minor trauma eg improper tooth brushing technique
-mild chronic inflammation
-frenum pulls
-ortho treatment
-excessive perio scaling
Describe what we should look for clinically when looking at recession. (4)
- stillmans clefts ‘v’ shape in gum
- mcCall’s festoons - gum has a rolled margin
- clinical recessions
- RADIOGRAPHS DO NOT AID DIAGNOSIS
List some of the problems associated with recession (3)
- dentine hypersensitivity
- root caries (as more of root is exposed)
- toothbrush abrasion
what is localised recession usually caused by?
usually seen on lower ants, due to fraenum pull, thin buccal bone covering
list some of the ways we can monitor recession (3)
clinically measure - LOA/pocket depths
clinical photographs
study models (3D record of the mouth)
list some of the treatment options for recession (3)
firstly, eliminate any casual factors
- modify brushing technique
- eliminate areas of mild chronic inflammation eg replace faulty restoration margins
- frenectomy for anteriors ie localised recession
Describe what furcation involvement is
this is the HORIZONTAL loss of support in areas where roots of MULTI-ROOTED teeth converge.
How can we diagnose a pt with furcations
these are diagnosed via radiographic AND clinical examinations (not just off a radiographic report alone)
radiographs suggest where they may be.
clinical examinations confirm if they are present or not.
IT NOT EXPOSED IN MOUTH IT IS NOT A FURCATION - needs to be verified clinically - as with everything eg caries, restorations etc
What is the index called that we use to measure furcation involvement in the mouth
HAMP ET AL
Grade 1 - horizontal loss of support. less than a 3rd of the way through
Grade 2 - horizontal loss of support. more than a 3rd of the way through
Grade 3 - ALL the way through
Why should we be worried about a furcation involvement on a tooth (3)
due to it REDUCING THE PROGNOSIS of a tooth. There are 2 reasons:
1. Furcations are more difficult to clean hence less control of disease as hard to clean
2. Loss of vitality of the tooth may occur due to accessory canals running from the pulp chamber into the furcation area act as a stagnation area for bacteria etc.
Because of the reduced prognosis of furcation involved teeth, what should we carry out at regular intervals
VITALITY TESTING
What are the treatment options for furcation involvement
either to expose the furcation for access for easier cleaning or to induce regeneration of new bone ie guided tissue regeneration
What are the treatment options for a grade 1 furcation
scale/polish, RSD/PMPR, OHI
furcationplasty - where a bur is used to widen the lesion reshaping it making it easier to clean.
list some of the treatment options of a grade 2 furcation (5)
- furcationplasty
- tunnel preparation (open all the way up and make it a grade 3 through-through)
- guided tissue regeneration
- root resection - where one root is cut off and removed so we have no furcation lesion left to worry about - making it a single root.
- tooth XLA due to poor prognosis
treatment options for a grade 3 furcation (3)
tunnel prep
root resection
tooth xla
what is the BEST treatment for a furcation involvement on a tooth (4)
GOOD OH
- make pt aware of where furcation involvement is
- explain why important to pay particular attention to this area
- use single tufted toothbrushes etc.
Describe the chemical composition of dentine
70% inorganic (hydroxyapetite crystals)
20% organic (collagen)
10% water
What does dentine contain?
collagen, mucopolysaccharide ground substance processes of the odontoblasts
where to the odontoblasts lie in dentine
PERIPHERY OF PULP - while their processes extend from their cell bodies to the amelo-dentinal junction
what is the function of dentine tubules
the dentinal tubules allow passage of fluid, chemical agents and bacteria
What is secondary dentine?
Describes the dentine that is produced AFTER the tooth has become fully formed. it is formed slowly throughout life preferentially deposited on the floor and roof of pulp chamber.
What is tertiary dentine
this is produced when the dentine is in contact with a noxious stimulus such as caries or tooth surface loss
odontoblasts lay down more dentine
is dentine highly innervated
YES
what is the definition of dentine hypersensitivity
pain arising from exposed dentine typically in response to chemical, thermal or osmotic stimuli that cannot be explained as arising from any other form of dental defect or pathology.
Where do we get most sensitivity from in a tooth
it is more sensitive at the dentinoenamel junction and close to the pulp. if the pulp is inflamed, the dentinal sensitivity is increased (even only slightly)
How can we treat dentine hypersensitivity? (5)
PREVENTION FIRST
REMOVE CAUSE IF POSSIBLE
Occlude tubules topically eg sensodyne (potassium ions)
Insulative restoration (protect the tubules from being exposed)
May have to DEVITALISE TOOTH eg RCT
How can we prevent dentine hypersensitivity from happening in the first place? (4)
INSTIGATE PREVENTION!
- REDUCE DIETARY ACID!
- advise pts not to brush teeth immediately after brushing (increases amount of tooth surface abraded with tooth brush - wait an hour)
- show pt correct brushing method
List the ideal properties of a desensitising agent: (7)
- non-irritant to the pulp
- relatively painless on application
- easily applied
- rapid onset of action
- effective permanently
- should not stain the teeth
- consistently effective
list the 7 desensitising agents (7)
sodium fluoride
stannous fluoride
sodium monofluorophosphate
calcium hydroxide
strontium hydroxide
formaldehyde
resins and adhesives
List some properties of sodium fluoride (3)
fluoride from sodium salt is taken up into dentine making it more resistant to acid decalcification
Possible increase in secondary dentine formation which will block dentinal tubules
MUST be applied frequently for benefit!
can be found in paste, gels, mouthwashes (THINK DURAPHAT)
What is sodium monofluorophosphate used in?
TOOTHPASTE (fluoride salt)
What is the role of calcium hydroxide? (2)
sometimes used as a LINING for fillings, occludes dentinal tubules but adheres POORLY to dentine therefore uncertain efficacy