Paper 2: CP (Endo, Perio, Cons, Paeds, OS) Flashcards
Aetiology of pulpal and periradiuclar disease
Bacterial entry towards/into pulp/RC due to
- caries
- cracks
- trauma
- resorption
- Perio problems
- microleakage
Compare the changes in pulp seen as bacteria penetrate and the Tx options
Insignificant changes; bacteria within 1.1mm pulp
- reversible
- Tx: remove caries, appropriate restoration
Irreversible damage; bacteria within 0.5mm pulp
- pulp inflamed, areas of necrosis and abscess
- Tx: RCT (pt compliance?)/XLA
- eventually -> pulp death + periradiuclar radiolucency
Discuss the distribution of bacteria in the RC
More bacterial coronal
- why prep. coronal before apical
Coronal: facultative anaerobes
Apical: obligate anaerobes
Within RC NOT in periapical lesion
What is the periapical lesion?
Inflammatory lesion
1st line defence to prevent bacteria entering periapical tissue
If becomes chronic bacteria invade tissues
What is apical periodontitis?
Periapical tissue response to bacteria threat from RC
Compare acute and chronic apical periodontitis
Acute: acute inflammation @ apex
- possibly due to
— response to irritants in healthy periapical tissue
— infection; may develop into 1ry abscess
— acute exacerbation of chronic apical periodontitis
- PMNs restricted to small area = micro-abscess
— if engulf whole periapical area = dento-alveolar abscess
Chronic Apical Periodontitis
- inflammation @ apex of non-vital tooth = periapical granuloma
- granulomatous tissue
- lymphocytes, macrophages, plasma cells
- non/epithelialised
Compare periapical true and pocket cyst
Periapical true cyst
- distinct pathological cavity completely enclosed by epithelial lining
- no communication w/ RC
Periapical pocket cyst
- apical inflammatory cyst
- sad-like epithelial lined cavity
- open to and continuous w/ RC; responds to RCT
Compare microorganisms in 1ry and persistent/2ry infections endodontic infections
1ry
- gram+ and - (prevotella, porphyromonas, fusobacterium)
- polymicrobial
2ry
- monoinfection
- gram+, cocci facultative anaerobes
Discuss yeasts and Enterococcus faecalis in relation to endodontic infection
Yeasts; C. Albicans most common
- found in 1ry and persistent infections
- RF teeth w/ therapy resistant periapical lesions(retreatment)
Enterococcus faecalis
- gram+, extra-oral bacteria
- found in 1ry infection
- predominant species in RF teeth w/ unsuccessful outcome
Ecology of RC
Warm, moist Nutritious Anaerobic Largely protected form host defences Bacteria can communicate w/ each other Produce virulence factors -> tissue damage
Discuss bacterial survival in RC
Planktonic state
- free floating; not attached to surface
- single cell or clumped
Biofilms
- community of microorganisms + EC polymer attached to surface
- resist treatment
— exopolysaccharide (bacteria embedded in) resist diffusion antimicrobial
— different cell layers may act as barrier to diffusion
— lay dormant, more resistant to killing
— specific resistance mechanisms
Mechanical methods of diagnosing periapical disease
Palpation: compare contralateral, -ve doesn’t mean no inflammation Percussion Periodontal probing - narrow pocket — tooth # — RC infection draining creating sinus tract Tooth slooth Transillumination Dentine sensitivity
Possible differential diagnoses for percussion+
Infected pulp O trauma Sinusitis Cuspal # PD disease Apical inflammation
4 soft tissue changes seen in pulpal disease
Reversible pulpitis
Irreversible pulpitis
Hyperplastic pulp
Pulp necrosis
Discuss reversible pulpitis
Possibly due to
- caries
- erosion, attrition, abrasion
- operative procedure
- mild trauma
- scalding
Symptoms
- transient pain
- ceases when stimuli removed
- TTP-
X-ray: normal periradiuclar appearance
Tx
- cover exposed dentine
- remove stimulus
- remove stimulus + dress tooth
Discuss irreversible pulpitis
Due to severe insult on pulp Symptoms - severe, spontaneous pain - lingers; min-hr - Exacerbated: hot liquids; Relieved: cold - PDL involved, pain becomes localised
X-ray: normal periradiuclar appearance; late stage PDL widened
Tx: RCT/XLA
Discuss hyperplastic pulp and pulp necrosis
Hyperplastic pulp
- form of irreversible pulpitis called pulp polyp
- proliferation of chronically inflamed young pulp tissue
- Tx: RCT/XLA
Pulp necrosis
- end of irreversible pulpitis
- Tx: RCT/XLA
Hard tissue changes seen in pulpal disease
Pulp calcification
Internal resorption
Discuss pulp calcification
Physiological 2ry dentine continually deposited post- tooth eruption and root formation
Deposited on pulp chamber floor and ceiling, not walls
W/ T occludes pulp chamber
3ry dentine deposited in response to stimuli
- reactionary: mild
- reparative: string noxious; rapid, irregular, cellular inclusion
Discuss internal resorption
Pulp inflammation may result in resorption of dentine by dentinoclasts
Clinically: pink spot
X-ray: punched out lesion continuous w/ rest of pulp cavity
Tx: RCT, XLA (if lesion too advanced)
Compare cracked tooth in non/vital teeth
Vital - pain — sharp on biting/release, occasionally from cold — difficult to localise - Ix: tooth slooth, staining, transillumination - L6-8, esp. 6 - Tx: ortho/Cu band/temp. crown — progress to cusp coverage restoration
Non-Vital
- pain: dull ache on biting
- Ix: TTP, narrow Perio pocket adjacent to #
- X-ray: halo, J shaped diffuse lesion around root
- Tx: XLA, consider hemisection
Possible Tx options for reversible pulp damage
Indirect pulp capping (stepwise)
- infected softened dentine removed
- layer non-infected dentine left over pulp
- Ca(OH)2 placed, restore
- 6/12 later remove softened dentine, place Ca(OH)2, restore
Direct pulp capping - pulp exposed through non-infected dentine — no recent history spontaneous pain - Ca(OH)2/MTA placed - bacteria tight seal - 12/12 check X-ray + sensibility
Discuss treatment options when pulp damage is irreversible
Pulp amputation - remove part of exposed inflamed pulp; remaining pulp tissue preserved - superficial damage: partial pulpotomy - coronal damage: coronal pulpotomy -
Pulpectomy - total pulp removal followed by RCT - indicated when — pulp irreversibly damaged — pulp cavity req. for retention
Contra/indications for RCT
Indications
- functionally and aesthetically important w/ reasonable prognosis
- irreversibly damaged/necrotic pulp
— w/ or w/o clinical/X-ray finding of apical periodontitis
- elective devitalisation
- dubious pulp prognosis prior to preparation
Contraindications - can’t be made functional or restored - insufficient PD support - poor prognosis: extensive restoration, vertical #s - pt — poor OH; unable to rectify in time — uncooperative — limited opening - complex anatomy: dens in dente
General success rates for RCT
1ry: 85-95%
Re-RCT: 77-80%
Flare ups: mild discomfort - severe pain + swelling post-treatment
Function of posts in RF teeth
Retention
Do not strengthen roots
3 aims of RCT
Remove + destroy microorganisms from RC system
Prevent bacterial re-entry from coronal by sealing RC
Allow body to heal
What is importance of the coronal seal of RCT?
Aim of RCT is to remove all bacteria from RC system
Important, common cause of failure is coronal leakage thus need to have good seal to prevent bacteria ingress
How to prevent coronal leakage during and after RCT
During - RD; only TIQ - remove caries - interim restoration — IRM, GI, Am — Cu/ortho band; esp. molar as likely to #
After - coronal aspect RF protected — 2mm of IRM/Am/comp — GIC if 3+wks - sound coronal restoration
Burs req. for RCT
Tapered Diamond
Safe Ended Diamond/T
- round ended; won’t over prep/damage
- remove excess around canal orifice
- smooth cavity walls after reaching depth + shape
Goose Neck: long shank, excavate undercuts
LN: v fine
What is the DG16?
Instrument used in RCT
Has 16mm shank
Used to explore canal orifice pre-op
Discuss rotary files used in RCT
ProTaper SX Shaping File
- NiTi
- use: shape coronal 1-2/3
- shorter (cf other ProTaper); 19mm
- D0 = 0.19mm; 9 rapidly inc. % tapers
- diameters ~= GG
3 main hand files used in RCT
Hedstrom
Flexofile
K-flex
Standards for SS hand files
Lengths: 21/25/31mm
Cutting length: 16mm
Taper: 0.02 (2%)
Define helical angle and pitch (hand files)
Helical angle: angle of cutting flutes to long axis of file
Pitch: cutting flutes/mm
Compare Flexofile and K-flex files
Flexofile - twisted SS - flexible, non-cutting tip - 45 degree helical angle - cross-section changes between sizes — rectangle; 6-10 — triangle; 15-40 — rectangle; 45+ - rotational + push-pull filing
K-flex
- twisted SS
- rigid (cf Flexofile), cutting tip
- cross-section: diamond, 2 cutting edges
- rotational + push-pull filing
Discuss Hedstrom files
Machined SS
Tapered intersected cones in spiral
Cross-section: speech bubble/elliptical
Push-pull filing only
Principles of safe RC irrigation
Never bind: move needle in + out slowly
Side venting needle: prevent pushing through apex
Never inject
Slowly: finger pressure
4 commonly used irrigants for RCT
Sodium hypochlorite
Chlorhexidine
EDTA
Aqueous Iodine
Discuss NaOCl
Gold standard
Antibacterial
Dissolves organic tissue remnants
Usually used 2.5%: 0.5-5.25%
Accident
- severe pain
- swelling
- extreme blanching
- bloody exudate
Tx
- irrigate w/ sterile H2O
- reassure
- immediate referral to maxfax
Discuss the other irrigants used in RCT
Chlorhexidine
- 0.2-2%
- antibacterial
- doesn’t dissolve organic tissue
- don’t use w/ NaOCl
EDTA 17%
- removes smear layer
- helps in sclerosed roots
- alternate w/ NaOCl; deeper penetration of antibacterial
Aqueous Iodine
- use: therapy resistant cases
- effective against broad spectrum bacteria
- flush w/ NaOCl remove brown staining
- possible allergic reaction
In 2 appointment RCT what is the procedure for temporarily sealing RC?
Dry canal w/ paper points held in tweezers
Place non-setting Ca(OH)2 in RC
Place cotton pledget or grey cavit G over orifice
IRM/Fuji IX interim dressing
Easily removed 1-2wks later w/ H2O/NaOCl, agitate w/ files
Discuss the movement of hand files in RCT
Rotational: watch winding
- place passively into canal
- rotate clockwise until lightly engage dentine
- pullback, rotate anti-clockwise
- passively into canal again; repeat
Negotiate canals gently
Regularly clean flutes of instruments
Principles of RCT access cavity
Remove all pulp chamber contents
SLA to all RCs
Allow inspection of pulp chamber
RCT procedure sequence
Access: SLA, remove pulp chamber Pre-op X-ray - estimated WL (whole length - 1mm) - tip to pulp roof length Explore coronal 1-2/3 w/ 10F Shape coronal 1-2/3 w/ SX Explore apical 1/3 w/ 10F Patency - 10F; 1.5mm>WL (through apical constriction) Definitive WL X-ray w/ 15F - 10F doesn’t show on X-ray - stopper in reproducible area - if >3mm from RA; adjust file + retake Prepare apical 1/3 - Serial Step Back - Step Back Smooth canal circumferentially - 20/25F 1mm from WL Choose master GP: tugback+, to WL Midfill X-ray: M.GP + 2-3 accessory points - M.GP within 1mm RA - accessory points 1mm back Complete obturation Post-op X-ray
Reasons for establishing patency during RCT
Prevent blockage of canal
Check for exudate
Aid irrigant apically
Maintain + follow anatomy
Principles of serial step back and step back
Serial Step Back
- getting apical constriction to MAF
- 15-20-25F @ WL
- MAF should be 25 or 30F
Step Back
- after completing serial step back
- 30F @ 1mm
Why use crown down approach for RCT?
Necrotic bacteria more coronal; removing stops introducing apically Achieve SLA - red. curvature - improve tactile sensation - greater vol. irrigant
What is the aim of apical preparation in RCT?
Get file slight larger than natural RC to WL
- ensures optimal cleaning
- provide resistance form to obturate against
Discuss the desired canal taper in RCT
Greater canal taper created by using inc. file tip diameters in incremental step back
Standard taper = 5% (0.05mm D inc. every 1mm)
Reason for using intracanal medicaments?
During 2 appointment RCT
Eliminate remaining bacteria after canal instrumentation and irrigation
Examples of intracanal medicaments
Non-setting Ca(OH)2 Steroids: ledermix ABs Potassium iodide Aldehyde:formacresol
Discuss properties of non-setting Ca(OH)2
Antibacterial
High pH
Degraded residual organic tissue
BaSO4 can be added to provide radiopacity
Discuss the problem of flare ups post-RCT and Tx options
Range from mild discomfort to severe pain and swelling
Occurs in 3-5% pt post-RCT
Tx range
- painkillers
- access and irrigation
- instrumentation and redressing
- incision and drainage
- systemic involvement: ABs
Discuss the problems that may arise w/ incorrect instrumentation during RCT
Ledges: irregularity in RC impeding access to apex
- negotiate w/ precurved 10F
- create good coronal flare during coronal prep
Blockages: packing of dentine tubules w/ debris
- copious irrigation
- small file + light picking motion feeling for stickiness
Perforations: iatrogenic creation of communication b/w RC + bone/PDL
- if enclosed in bone better prognosis cf one in contact w/ OC
- repair ASAP
- GIC or MTA
Separated instrument
- coronal 1/3: remove
- mid 1/3: more difficult
- apical 1/3: impossible
- bypass separated instruments
- better prognosis if post-shaping + cleaning
4 aims of obturation
Prevent microorganisms and toxins percolating into peri-radicular tissue
Seal remaining bacteria in unfavourable environment of RC
Prevent percolation of peri-radicular exudate (nutrient) into RC
Prevent reinfection from coronal
Requirements for obturation
Tooth asymptomatic
Temp. dressing intact
No sinus present
RC dry
Ideal properties of RC filling material
Easily introduced into RC Dimensionally stable Seal RC; apically, lat., coronally Impervious to moisture Nonirritant (peri-radicular tissue) Nonstaining Bacteriostatic Radiopaque Removable Long shelf life Allow good length control
Discuss GP and name other RF materials
GP
- most widely used
- trans-polyisoprene; isomer of natural rubber
- biocompatible (latex allergy caution)
- insoluble
- can’t be heat sterilised
- degrades in light
Silver points
Acrylic
Pastes
Ideal properties of RC sealer
Satisfy req. of RF material Good adhesion to canal wall Fine particle size (easy mix) or 2 paste Adequate working T Expand whilst setting
Examples of RC sealers
ZOE
Setting Ca(OH)2
Resin
GI
Obturation techniques
Lat. condensation; cold + warm Thermo-mechanical compaction Vertical condensation Thermo-plasticised GP Carrier based Barrier
Cold lateral condensation technique
Finger spreader loose @ WL M.GP to WL ideally tugback+ - cut tip, try another, change size - less accurate cf files Dry canal w/ paper points Coat M.GP tip w/ sealer, place to WL Finger spreader 1mm midfill X-ray Continue placing accessory GP until canal full Sear GP off ~1mm below canal orifice -> post-op X-ray
Methods to sear GP
Heat carrier + Machtou plugger
System B
Discuss system B
RC obturator Set on touch not continuous 200 degrees not higher Use touch coil to activate heated tip Use for 3s then remove heat
Criteria for RCT post-op assessment
Length; same as WL
Condensation quality; voids?
Taper; adequate, even throughout
Assessing outcome of RCT
Tooth function restored w/ no swelling or sinus tract
Pt asymptomatic
X-ray
- normal peri-radicular tissue
- healing (if was peri-apical lesion @ start)
— poor obturation associated w/ 65% non-healing re-RCT cases
Rationale for partial pulpotomy
Pulp is usually only inflamed to depth of 2mm
- remove inflamed/necrotic pulp + leave healthy pulp tissue under
- allows root formation to continue in immature permanent teeth
Partial pulpotomy procedure
Remove pulp 2mm apical to exposure w/ HS diamond bur
Control haemorrhage; saline soaked cotton pledget
Cover pulp w/ MTA or non-setting Ca(OH)2
Seal w/ GIC, restore (comp)
Re-evaluate 6-8wk, then, 12/12 monitor vitality and root development
What is apexification?
Method of inducing formation of calcified barrier @ apex of non-vital teeth w/ incomplete root formation
Apexification rationale
RCT Tx difficult: wide, funnel shaped canals
Ca(OH)2 dressing results in formation cementum-like hard tissue barrier; aids final obturation
Apexification procedure
Access
Chemo-mechanical cleansing
- moderate lat. pressure + vertical movements on dentinal wall
- chlorhexidine or 0.5% NaOCl
Fill w/ Ca(OH)2 comoressed w/ cotton pledget
- endure contact w/ vital apical tissue
Repeat 3/12 for 18-24/12
- once apical barrier forms complete obturation
If after 2 years an apical barrier does not form after apexification what is the Tx?
Use MTA to form artificial apical barrier
Aim of pulp therapy in deciduous teeth
Maintain vitality of teeth + supporting tissue
Maintain dental arch space for permanent teeth
Pulp therapy techniques for deciduous teeth
Indirect pulp cap; Ca(OH)2
Pulpotomy
Pulpectomy
Indirect pulp cap; success unreliable, not recommended for carious exposure
Difference b/w pulpotomy and pulpectomy
Pulpotomy
- only removes inflamed coronal pulp
- healthy tissue below saved
- whole coronal or partial
Pulpectomy: total removal of pulp followed by RCT
Contra/indications for pulp therapy in deciduous teeth
Indications - general — medical contraindication for XLA (bleeding) — cooperative pt — psychologically advantageous - dental — previous Tx experience (LA) — regular pt
Contraindications - general — medical: cardiac lesion, debilitating illness — uncooperative — -ve attitude pt/parent - dental — unrestorable — bone loss — several teeth w/ pulp involvement — acute abscess w/ cellulitis — close to exfoliation
Aim of pulpotomy
Remove inflamed coronal pulp
Preserve remaining radicular pulp
Maintain tooth viability
Contraindications for pulpotomy
Uncooperative Bone loss Resorption Irreversible pulp damage/pulpitis Unrestorable
Potential pulpotomy materials
Formocresol (no longer recommended) Ca(OH)2 Ferric sulphate Gluteraldehyde MTA
Discuss ferric sulphate use in pulpotomy
Fe2SO4 15.5%
- in contact w/ blood forms ferric ion complex
— mechanically seals blood vessels
- no healing
— preserves vital tissues
— conserves radicular pulp w/o reparative dentine formation
- no systemic effects (formocresol)
- clinical, X-ray, histological outcome similar formocresol
For deciduous teeth what is the best medicament?
Ferric sulphate: 86% 2yr success rate
MTA has better clinical + radiographic outcome but too expensive currently
Aim of pulpectomy
Remove irreversibly inflamed/necrotic radicular pulp
Clean RC
Obturate RC w/ filling material that resorts @ same rate as 1ry tooth
Indications for pulpectomy
Cooperative
Irreversible pulpitis: symptoms and/or clinical finding
Non-vital radicular pulp w/ or w/o associated infection
Discuss the verbal and non-verbal communication aids in paeds
Verbal - honesty: tell how it may feel - empathy, support - voice control: tone, pitch, speed - age appropriate — simple, soft, non-threatening — tell what to do and when
Non-Verbal - body language: open, engaged - height and position — eye level — in front of pt - pre-appt info - preparatory video/pictures - child waiting area: posters @ eye level
What are the aims of the parent-child-operator triangle?
Build trust in parent and patient
Build compliance
Foster +ve dental attitudes and behaviours
Dynamics in the parent-child-operator triangle
Parental involvement
- physical support
- discuss + obtain consent: Tx, holding still
Advocate for child
Respect autonomy
- agree stop signal together
- give choice where possible: L or R filling today?
Define anxiety and give different types seen in children
Anxiety: general feeling of unease; nervousness, uncertainty, worry
Types
- maternal
- personality trait: consistent personality attribute
- state: specific situation
Factors affecting anxiety in children
Age; pre-cooperative?
Separation anxiety: infancy to 4/5yrs
Coping ability generally inc. w/ age but anxiety may too
Learning disability: low coping ability
Communication disability: selective mutism
Sensory: visual, hearing
Emotional: behavioural
9 possible non-pharmacological behaviour management strategies for children
Graded Experience Acclimatisation Tell Show Do Behaviour Shaping Modelling \+ve/-ve Reinforcement Distraction Desensitisation
Discuss graded experience and acclimatisation
Graded Experience
- gradual introduction to dental surgery
- non-threatening/invasive procedures first
Acclimatisation
- repeat simple interventions
- build familiarity
- new produces 1 at a time
Discuss behaviour shaping and modelling
Behaviour Shaping
- hierarchical exposure to dentist
- reinforce desired behaviour, progress towards
- feedback: +ve, timely, specific
- if -ve response; show empathy, return to previous stimulus
Modelling
- direct observation of pt w/ consent or video demo
- model is similar age for similar procedure
- show entering + leaving; emphasise +ve outcome
Discuss +ve and -ve reinforcement
+ve
- identify desired behaviour + comment on it
- shaping behaviour through appropriately timed feedback
— stickers, colour sheets, bravery certificate, reward chart
- ignore -ve behaviour
- ve
- shaping behaviour through removal of stimulus
- remove parents until demonstrate desired behaviour
Discuss distraction and desensitisation
Distraction
- diversionary tactics to dec. perception of unpleasantness
- visual: video/pics, props
- auditory: tell story, music
- motor: hold cotton wool roll, counting
Desensitisation
- mild exposure to anxiety provoking stimulus until no longer fearful
- build towards coping w/ procedure
- 3-in-1 alone, then light press -> full press
Distinguish b/w growth and development
Growth: anatomical phenomenon; inc. size/no
- hyperplasia
- hypertrophy
- secretion of ECM
Development: physiological phenomenon; inc. complexity
Distinguish b/w two types of ossification
Intramembranous
- new cells form on periosteum -> secretion of ECM -> mineralisation -> new layer of bone
Endochodrial
- replacement of cartilage w/ bone
- begins in and spreads out from 1ry ossification centre
What bones make up the cranial vault?
Frontal
Parietal
Squamous part of temporal
Occipital
What are the bones in the cranial vault separated by?
Sutures
At birth these are fontanelles
Describe growth of cranial vault
Intramemebraneous ossification
- apposition @ sutures and exterior
- resorption @ interior
Growth @ sutures
What bones make up the cranial base?
Sphenoid
Ethmoid
Petrous part of temporal
Basioccipital
Discuss growth of cranial base
Endochondrial ossification
- prior to ossification 1ry cartilaginous chondrocranium
Spheno-occipital synchondrosis; affects ant.-post. relation of jaw
Some surface remodelling
Discuss growth of maxilla
Intramembranous ossification
Growth @ sutures that connect maxilla to cranial base
- craniomaxillary: downward + forward displacement of facial skeleton
- saggital: inc. width of maxilla
Surface remodelling
Discuss growth of mandible
Intramembranous ossification
Endochondrial @ condyles: elongation in forward + downward direction
Surface remodelling
Compare sites of bone deposition and resorption in the mandible
Deposition
- Outer surface of body
- Post. ramus
- Chin
- Condylar cartilage
Resorption
- ant.-inf. aspect condyle
- labial roots L incisors
- ant. border ramus
- inner aspect mandible
Discuss growth rotations of mandible
Forward
- red. lower ant. facial height (short face)
- inc. overbite
- space closure difficult
Backward
- inc. LAFH (long face)
- red. overbite
- space closure easier
Define conscious sedation
SDCEP 2017
Technique in which drug/s produce state of depression of CNS enabling Tx to be carried out but during which verbal contact w/ pt is maintained
Drugs used in dentistry should carry margin of safety wide enough to render loss of consciousness unlikely
Aims of sedation for child and dentist
Child
- prevent/red. fear, anxiety, pain
- facilitate cooperation
- promote +ve attitude + response to Tx
Dentist
- facilitate safe provision and completion of quality care by min. disruptive behaviour
- leave child fir for safe discharge @ end of Tx
List agents used for conscious sedation in density
Inhalation: nitrous oxide, O2 (1st choice <12yrs)
Oral: benzodiazepines; midazolam
Transmucosal (nasal, sublingual): benzodiazepines
IV: benzodiazepines
Discuss ideal properties of sedative agent
Comfortable, non-threatening administration
Rapid onset
Predictable anxiolytic and sedative action
Controllable duration
Analgesic
No side effects
Rapid, complete recovery
Dis/advantages of NOx
Adv
- colourless, sweet smelling
- anxiolysis, mild analgesia
- hypnosis, euphoria
- non-irritant to mucosa
- low blood gas solubility; rapid induction + recovery
- weak: MAC 105%
- minimal metabolised (<0.01%)
- haemodynamic stability
- flexible depth + duration
Disadv - side effects: nausea, headache, unconsciousness - toxicity (long term) — B12 deficiency, anaemia — bone marrow suppression — inc. risk miscarriage - greenhouse gas - cost - space for equipment - req. good rapport - administration route near operating site
Indications for NOx sedation
Dental anxiety Long / traumatic procedure Gag reflex Medically compromised - high risk for GA
Contraindications for NOx sedation
Pre-cooperative Language barrier Refusal Nasal obstruction/congestion Inc. intracranial pressure
Respiratory infection - restricted airflow - coughing COPD - red. ventilation + gaseous exchange
Ear/eye surgery: rapidly fills air-filled cavity -> inc. pressure = pain
Immunocompromised: bone marrow suppression
Multiple sclerosis: exacerbates
Bleomycin chemotherapy
- anti-neoplastic AB used in lymphoma Tx
- risk lung damage -> pulmonary fibrosis
Signs and symptoms of conscious sedation
Signs - slight inc. BP + HR - peripheral vasodilation — flushing of extremities, face - red. muscle tone as anxiety red. - normal, smooth respiration
Symptoms
- lightness of extremities
- lightheadedness/dizziness
- wave of warmth
- tingling in H+F
- analgesia: numbness mouth, H+F
- euphoria
Signs of over sedation
Persistent mouth closing Spontaneous mouth breathing Red. cooperative Laughing, crying, giddiness Feeling of unpleasantness Nausea/vomit, headaches Sluggish/irrational response Incoherence
Contra/indications for GA
Indications
- pre-cooperative
- uncooperative (SCD)
- pain and/or infection can’t be managed by other means
- severe anxiety: can’t cope under LA/IHS
- multiple XLA in 2/+ quadrant
- complex Tx: surgical XLA/drainage, biopsy
- allergy to LA
Contraindication - significant comorbidity — complex cardiac problem — neuromuscular disorder: muscular dystrophy - allergy to GA drugs
Discuss the considerations that must be taken when Tx planning for child GA
All Tx carried out under 1 GA
Consider MH
Use pre-op X-rays
Restorative Tx considered; SCD, permanent molars
Prevention advice must be given
XLA 6s: seek ortho opinion
Avoid repeat: teeth usually deemed restorable are XLA’d
Define periodontitis
An infectious disease resulting in inflammation within the supporting tissues of teeth, progressive attachment and bone loss; characterised by pocket formation and/or gingival recession
Typical signs of periodontitis
Gingival inflammation BOP PD pocket CAL Alveolar bone loss/resorption Tooth mobility, teeth drifting Gingival recession/enlargement Tooth loss
On IO exam what is important to assess for PD condition?
Soft tissues OH Gingival tissues/bio-type Occlusion PD parameters Restorative problems + needs
What are the gingival bio-types?
Thick flat -> thick scalloped -> thin scalloped
What are the PD parameters used to assess PD health?
PPD CAL Furcation involvement - Class 1: <3mm - Class 2: >3mm but not through-through - Class 3: through and through Tooth Mobility - Grade 1: <1mm horizontal - Grade 2: >1/<2mm horizontal - Grade 3: >2mm horizontal or vertical Recession Plaque Bleeding Suppuration
Discuss chronic periodontitis
Most prevalent in adults (can occur in children) Host factors determine progression - usually slow->moderate rate - periods of rapid destruction can occur CAL = plaque levels
Systemic factors: DM, HIV
Local factors: tooth, iatrogenic
Discuss general features of aggressive periodontitis and compare localised and generalised aggressive periodontitis
General - healthy - familial aggregation - rapid rate of progression — may be self-arresting - plaque deposits inconsistent w/ severity - neutrophil function abnormalities
Localised
- early onset
- 6s and 1s
- freq. A.a. detection
- robust serum Ab response
Generalised
- usually <30y
- 3 other teeth than 6s/1s
- freq. A.a. and P.gingivalis detection
- poor serum Ab response
What is considered PD stability?
BOP <10%
PPD <4mm
Mobility
Differentiate b/w ideal and normal occlusion
Ideal: based on morphology of unworn teeth
Normal: minor irregularities in individual teeth but satisfies req. aesthetics + function
Discuss dentition at birth
Usually no teeth
Dental arches represented by gum pads
- U: wider, longer
Elevated segments = un-erupted teeth
Discuss timing of deciduous dentition and features
Timing
- calcification: 4-6/12 +/- 6/12 in utero
- eruption begins: L1s 6/12
- established: 2.5y
Features - incisors spaces - primate spacing — 2mm space — U: M Cs — L: D Cs - flush terminal plane — long axis Es flat — guides 6s in
Discuss development of permanent incisors
Develop P/L to A+Bs
Eruption
- L: 6y
- U: 7y
Inc. width accommodation
- pre-existing space
- proclination
- growth: inc. inter-canine width
What is the leeway space?
Feature of permanent 3-5s
Different in M-D width of 3, 4, 5s cf c, d, es
- L: 2mm/quadrant
- U: 1mm/quadrant
Discuss development of permanent molars
6s guided into 1/2 unit class 2 occlusion by flush terminal plane of Es
Once Es exfoliate
- 6s drift ant. closing leeway space
- > space on L = Class 1 occlusion
Main non-surgical PD therapy
OHI Smoking cessation Remove plaque retentive factors XLA hopeless teeth SP, RSD Adjunctive therapy if necessary
Ideal outcomes of PD Tx
Red. PD: 1-2mm
Red. CAL: 0.5-1mm
Red. P+B: <20%
Behavioural change: brush teeth, floss etc Systemic health - glycemic control (DM) - CVD Improved: long term prognosis + QoL - bleeding - halitosis - aesthetics
What is perio adjunct therapy?
Use of medications or devices in addition to nonsurgical PD Tx in order to supplement its efficacy
Rationale for use of antimicrobials for PD adjunct therapy
Bacterial aetiology of perio
Pathogens can invade tissues not reached w/ SP/RSD
Pathogens can inhabit oral niches not reached w/ SP/RSD
Disadvantages to antimicrobial adjunctive perio therapy
Plaque 50-300 layers thick, bacteria embedded in glycoside
- survive [AB 500-1000x]> than normally found in circulation
Systemic effects
Microbial resistance
Dis/advantages of local AB perio adjunctive therapy
Adv
- high dose directly on site req.
- red. side effects;
- assured compliance
Disadv
- doubtful substantivity
- AB resistance
Important considerations when deciding whether to use antimicrobial perio adjunctive therapy
Improved clinical outcome when used w/ NSPT
- additional CA gain 0.2mm
- additional PD red. 0.4mm
Most effective in severe cases
May red. cost
Mild adverse effects; mainly gastrointestinal
AB resistance
- use assessed carefully!
