MSA aggregated Flashcards
What are the cardinal signs in a Parkinsons patient?
- bradykinesia
- postural instability
- muscle rigidity
- resting tremor
What are 3 features of a Parkinsons patient that is in pain?
- frequent pulling at face and mouth
- refusal to eat
- disturbed sleep
What is the dental relevance of Parkinsons disease?
- mask like face (hard to judge & slow speech)
- hard to access surgery
- dry mouth
- impaired dexterity OH deteriorates
- lack muscle control (dentures
- dysphagia
What is the difference between a patient with Parkinson’s disease and a patient with cerebral disease?
P = resting tremor
CD = intention tremor
List 2 different types of dementia?
- Alzheimer’s
- Lewy bodies
What legislation is relevant for dementia patients? (5 marks)
- mental health act 2003 (scotland)
- mental capacity act 2005 (england/wales)
- adults with incapacity act 2000
- equality act 2010
- human rights act 2000
List some of the people who make up the multidisciplinary team of a dementia patient:
- GMP
- GDP
- Consultant neurologist
- Staff nurse
- Domestic nurse
- Carer
- Physiotherapist
What are symptoms of early stage dementia?
- difficulty concentrating
- decreased memory of recent events
- socialising becomes difficult
- confusion
- poor judgement
- anxiety
What are symptoms of middle stage dementia?
- major memory deficiencies
- dont know where they are/what day it is
- incontinence
- personality changes
- risk of wandering
What are symptoms of late stage dementia?
- lack of communication
- assistance required for most activities
- may be bed bound
- difficulty swallowing/eating
List some risk factors for development of oral cancer:
- smoking
- drinking alcohol
- HPV
- age
- chewing tobacco
- male
- family history
What are the ideal properties of a luting agent?
- low viscosity
- low thickness
- easy to use
- radiopaque
- good marginal seal ability
- low solubility
- cariostatic
- biocompatible
- good mechanical properties
What material is mainly used for luting of posts & crowns?
GI normally used, lower particle size to allow a better seal
Why is RMGI not used to lute posts & crowns?
Contains HEMA. This is cytotoxic & causes swelling
Is composite hydrophobic or hydrophilic?
hydrophobic
How is a porcelain veneer treated in the lab to increase retention during use?
etched with hydrofluoric acid
How is a metal ceramic crown treated in a lab to increase retentiveness during use?
sand blasted
What is the name given to a space between upper central incisors?
diastema
What is a common cause of a midline diastema in paeds patients?
low frenal attachment
How is fluorosis of a child’s teeth likely to have happened?
excess ingestion of fluoride during development of the teeth
What are 2 treatment options for fluorosis?
- microabrasion
- composite restoration
A child patient is deemed as ‘high risk’ for development of caries, what are some potential reasons for this?
- existing restorations
- clinical evidence of new clinical lesions
- early loss of primary teeth
Give 3 fluoride containing preparations, and their doses, which would be suitable to give to a high risk patient who lives in an area with less than 0.3ppm fluoride in the drinking water:
- Duraphat/Fluoride varnish 22600ppm
- Fluoride toothpaste 1450ppm
- Fluoride mouthwash 225ppm
What is the name of the term given to the forward movement of teeth into an extraction space?
mesial drift
You take bitewing radiographs of a 6 year olds teeth, these showed minimal caries in the upper left first permanent molar. What type of restoration would you place?
preventative resin restoration
In which type of malocclusion is injury to the upper anterior teeth most likely to occur?
class II div. 1
List 3 ways of monitoring teeth that have suffered trauma long-term:
- colour
- vitality testing (EPT or Ethyl Chloride)
- percussion
There is evidence of marginal gingivitis in your patient. Give two chair side methods of improving their oral hygiene:
- disclosing tablets/solution with toothbrushing demonstration
- polish with prophy paste
Name some congenital cardiac abnormalities:
- atrial septal defect
- ventricular septal defect
- mitral valve stenosis
- aortic valve stenosis
What are the 7 elements of caries risk?
- clinical evidence
- fluoride use
- medical history
- social history
- plaque control
- dietary habits
- saliva
What are the 3 elements that must be present for situation to be deemed as child abuse?
- significant harm to child
- child’s carer has some responsibility for that harm
- signifiant connection between carers responsibility to child and the harm of the child
what are the markers of child abuse?
- nutrition
- warmth, clothing and shelter
- hygiene & healthcare
- stimulation & education
- affection
What is the index of suspicion for child abuse?
- delay in seeking help
- vague story
- account not compatible with story
- parents mood abnormal
- parent behaviour call for concern
- child appearance & interaction with parents abnormal
- child says something
- history of previous injury
- history of violence within family
Why would a patient require periodontal surgery?
At re-evaluation stage, at least 4-6 weeks after completion of non surgical treatment
- pockets of 5mm or greater persist
- in the presence of excellent OH
What are the disadvantages to pocket elimination?
- exposed root surface mat be unaesthetic
- exposed root surface may be sensitive
What pathogens are involved in acute ulcerative necrotising gingivitis?
- fusobacterium
- prevotella intermedia
what are the hall mark examination features of ANUG?
On exam
- punched out appearance of interdental papillae extending onto gingival margin
- ulcers covered with greyish slough which can be wiped away leaving bleeding tissue
- necrosis of gingival tissue eventually extending to PDL
What are the symptoms of a periodontal abscess?
- pain on biting
- swelling
- bad taste
- halitosis
What are some side effects of chlorhexidine mouth rinse?
- staining
- taste disturbance
What are the three main types of studies?
- cross sectional (descriptive)
- cohort and case control (analytical)
- clinical trial (experimental)
What is the difference between a cohort study and a cross-sectional study?
Cross sectional =
- the observation of a defined population at a single point in time
- used for estimating prevalence of disease or to investigate potential risk factors
Cohort =
- establish a group of individuals in a population
- measure exposures
- follow up over a period of time
- identify those that develop disease
what are the 5 R’s for smokers who are NOT thinking about quitting?
- relavence
- risk
- rewards
- roadblocks
- repetition
What is the difference between an overbite and overjet?
Overbite = extent of horizontal overlap between maxillary central incisors and mandibular central incisors is increased
Overjet = lower jaw too far behind upper jaw
What are the main displacement forces for URAs?
- gravity
- masticatory
- active component
- speech
- tongue
What are balancing extractions? Why are they done?
Extraction of tooth on opposite side of same arch
- done to prevent midline shift
When is an ideal time to extract poor prognosis 6s?
- bifurcation of the 7s
- 7s will experience mesial drift and take 6s space
- if done too early premolars will tilt backwards
What are the advantages of an Adam’s clasp?
- any tooth
- small/neat/unobtrusive
- can be used for both deciduous and permanent teeth
- can be modified as needed
What are the side effects of NSAIDs?
- GIT problems due to reduced production of prostaglandins
- Hypersensitivity
- Overdose problems
- Aspirin burns on mucosal surface
What drug treatment for RA can cause oral ulceration?
methotrexate
What drug treatment for RA patients can cause oral pigmentation?
hydroxychloroquine
What drugs are given to patients with epilepsy can how does this affect dental treatment?
Anticonvulsant drugs:
- phenytoin = gingival enlargement
- carbamazepine = dry mouth
What does INR mean?
International normalised ratio
- the ratio of a patients prothrombin time to a normal (control) sample
what are the steps in the chain of infection?
- infectious agent
- reservoir
- portal of exit
- mode of transmission
- portal of entry
- susceptible host
What are the modes of transmission of infectious diseases?
- direct
- indirect
- ingestion
- inhalation
- inoculation
- intercourse
- mother to infant
What is in the sinners circle?
- chemicals
- temperature
- energy
- time e
What is the vibrating line?
The junction between the hard palate and soft palate
How is a biofilm formed?
Steps:
- Adhesion
- Colonisation
- Accumulation
- Complex community
- Dispersal
What are the different micro-organisms that cause candidosis?
- candida albicans
- candida glabrata
- candida krusei
What are the treatments for candidosis and what are their modes of action?
Nystatin = bonds to ergosterol, causes pores to from in the cell membrane and leads to cell death (fungicidal)
Miconazole & Fluconzole = inhibits production of ergosterol (fungistatic)
Echinocandins = inhibits Beta 1, 3 glucan synthase
Which two organisms are resistant to fluconazole?
candida glabrata and candida krusei
What is the meaning of facultative anaerobic?
Microorganism that usually respires aerobically but can respire anaerobically if not air present
Why is rectangular collimation preferred in dental radiography?
greater dose reduction compared to circular
What are the names and direction of the two curves in bitewing radiographs?
Curve of Spee (antero-posterior)
- curves up posteriorly
- produces a happy smile
Curve of Monson (bucco-lingual)
- influences X-ray technique
What is cervical burnout?
Triangluar shaped radioluency at neck of teeth
- at contact points, less tooth to pass through therefor less attenuation and appears darker on radiograph
- may mimic root surface caries
What reference lines are used in panoramic radiology?
- Frankfort plane horizontal (lower border orbit to upper border external auditory meatus)
- Mid- saggital plane should be perpendicular to floor
- Vertical canine lines match maxillary canines
Describe how a panoramic radiograph is taken?
- patient positioned in machine ensure reference lines are in line
- vertical narrow beam of x-rays passes through patient from lingual to buccal
- x-ray tubehead rotates behind patient
- image receptor rotates around front of patient
What are the limitations to panoramic radiography?
- foccal trough narrow anteriorly = structures present may not be shown
- horizontal distortion
- long exposure time
- difficult with people with big shoulders
What is the function of the lead foil in film?
Primary function = to absorb scatter X-rays, to prevent image degradation
Secondary function = to absorb some of the primary beam
What are the 3 criteria for something to be deemed a ghost image?
- always appear above and on opposite side
- unsharp
- usually magnified normally in horizontal direction
Why are elevators used in oral surgery?
- to provide a point of application for forceps
- to disrupt the PDL before using forceps (loosen)
- to extract a tooth without forceps use
- removal of roots
What are the main aims of suturing?
- reposition tissues
- cover bone
- prevent wound breakdown
- achieve haemostasis
- encourage healing by primary intention
What are the different types of nerve damage?
Anaesthesia = numbness
Parasthesia = tingling
Dysaesthesia = pain, unpleasant feeling
Hypoaesthesia = reduced sensation
Hyperaesthesia = heightened sensation
How would you manage a dry socket?
- reassure patient and advise systemic analgesia
- LA block
- irrigate socket with warm saline and curettage to encourage new clot formation
- give advice on analgesia
- pack with alvogel
What is a sequestrum?
A piece of dead bone that has become separated during the process of necrosis from normal or sound bone
What are three specific warnings you would give to a patient after prescribing them with Metronidazole?
- do not drink alcohol
- not suitable for pregnant patients
- seek medical attention if you experience an adverse reaction
Your patient admits that they are very dependent on tobacco. Give a definition of dependence:
Compulsive psychological and physiological need for a habit forming substance (in this case smoking/tobacco)
There are various evidence based treatments that can be used to help support patients who want to quit smoking. Give TWO examples:
- E cigs
- nicotine patches
What are 4 factors that can contribute to the development of oral candidiasis?
- immunosuppression
- antibiotic use (prolonged)
- poor oral hygiene
- denture use with poor hygiene
Name the organism and virulence factor which causes oral candidiasis:
Candida albicans
- production of hydrolytic enzymes
- production of protective biofilm
What are the steps in biofilm formation?
- adhesion
- colonisation
- accumulation to form complex community
- dispersal
Give 2 examples of antifungals prescribed to treat oral candidiasis and the mechanism for each:
- FLUCONAZOLE = inhibits the synthesis of ergosterol which is an essentially component of fungal cell membranes (without this the cell membrane becomes permeable leading to cell death)
- NYSTATIN = binds to ergosterol in fungal cell membranes, leading to the formation of pores and leakage of intracellular contents (topical application)
List 5 functions of the placement of a provisional crown in dentistry:
- Improve/restore aesthetics
- Facilitates speech and mastication
- To maintain tooth position and occlusion
- Protection of the prepared tooth before definitive restoration
- Allows evaluation and adjustment
Name 3 types of prefabricated crowns used in dentistry:
- metal crowns
- PFM crowns
- clear plastic crowns
List 2 disadvantages of using prefabricated crowns:
- inaccurate fit/limited customisation
- costly to have large bank of crowns in practise
Explain the pattern of distribution of decay in nursing bottle caries:
- upper incisors and first molars worst affected
- lower incisors free from decay due to shielding from tongue
Give four signs of late stage dementia:
- severely impaired communication
- loss of motor function
- typically bed bound
- incontinence
List 3 ways in which a dental practise can be made dementia-friendly
- Having walls a different colour from floors skirting and doors to provide good visual contrast to aid way finding
- Avoid clutter
- Ramps & disabled toilets
- Avoid non-essential signs
What is meant by a dentally fit patient?
Patient is free from dental disease and infection
What is a MDT? list three possible members:
A team of healthcare individuals from a wide variety of disciplines/specialities who work alongside each other in order to provide comprehensive and holistic care to patients
- GDP
- physiotherapist
- GMP
- nurses
Name three complications associated with radiotherapy to the head and neck?
- Xerostomia
- Osteoradionecrosis
- Radiation induced caries
Name four conditions of tooth number that can result in malocclusion:
- Hypodontia (missing teeth)
- Supernumerary teeth (extra teeth present)
- Retained primary teeth
- Unscheduled loss of teeth
What are 2 roles of epidemiology?
- identifying and investigating the causes and risk factors of diseases
- to develop and implement strategies for disease prevention and control
Define incidence:
the number of new cases of a disease that occur in a specific population during a defined period of time
Define prevalence:
the total number of cases of a disease/health condition that exist in a specific population at a given point in time
What is work hardening?
- dental material is subjected to repeated deformation or stress
- crystal structure of material is distorted causing dislocations within crystal lattice
- these dislocations move through the crystal lattice and interact with each other forming more dislocations
- dislocation pile up making it harder for them to move on
- accumulation of dislocations within material results in a strengthening of material
- increased strength
Give 2 disadvantages of using PMMA:
- low impact strength (susceptible to fracture)
- residual monomer can cause allergy
List four factors than can contribute to tooth mobility:
- periodontal disease
- trauma
- bruxism
- dental abscess
In what instances of tooth mobility would you intervene?
- mobility is getting increasingly worse
- mobility is giving rise to symptoms (eg pain)
A patient has mobile lower incisors and refuses XLA. What would you advise him and what are the disadvantages of this?
- splinting the teeth (if mobility is causing difficulty chewing etc.)
- splinting will not stop the progressiveness of the LOA
- splinting can cause hygiene difficulties which may speed up LOA
- last resort treatment
Why is non-setting calcium hydroxide an ideal inter appointment medicament?
- biocompatible
- antibacterial properties
- promotes healing of periapical tissues by stimulating formation of mineralised tissue
- helps to dissolve organic matter like bacteria
What are the reasons for obturating in endodontics?
- to prevent re infection
- to provide structural support to tooth
- to provide a seal for restoration
- to prevent leakage of bacteria and fluids from oral environment
Why is sealer used in endodontics during cold lateral compaction?
- to fill any gaps and prevent voids
- to improve sealing ability
- to create a solid mass of gutta-pécha and sealer which provides structural support to tooth
What are 3 common features of Parkinson’s?
- bradykinesia
- rigidity of muscles
- resting tremors
What is the most likely reason for a Parkinsons patient having dry mouth?
anticholinergic effects of medications
Give three clinical reasons that could account for neuro-sensory deficit after the removal of the lower right third permanent molar:
- Nerve damage during surgical procedure
- Post-operative swelling or inflammation (compression or irritation of the nerves)
- Infection (surrounding the nerve)
What are the short term effects of child neglect?
Impaired:
- physical health
- emotional health
- social development
- cognitive development
What are the long term effects of child neglect?
High incidences of:
- arrest
- suicide attempt
- major depression
- diabetes
- heart disease
What might you see on a radiograph of a non-vital tooth?
- Ankylosis
- Internal root resorption
- External root resorption
- Periapical radiolucency
What is lip competence?
- upper and lower lip meet at rest
- maintain proper oral seal
- naturally rest against teeth to help maintain proper dental alignment and oral function
What are the problems associated with incompetent lips?
- longer face
- impeded speech
- mouth breathing
- may cause lip trap (leading to proclined upper incisors)
How can incompetent lips affect upper and lower incisors?
- upper incisors proclined
- retroclination of lower incisors
- overjet increased
- anterior open bite may occur due to teeth being apart
What are some symptoms of congestive heart disease?
- shortness of breath
- fatigue or weakness
- swelling in legs, ankles, feet or abdomen
- rapid or irregular heartbeat
- persistant cough or wheezing
- reduced ability to concentrate/think clearly
- loss of appetite
What medication classes are used to treat heart failure?
- ACE inhibitors
- beta blockers
When preparing a patient for a panoramic radiograph what do you tell them to do?
- remove metal foreign bodies from head & neck
- press tongue to roof of mouth
- extend neck
- stay still
- do not talk or swallow
- scan will take approximately 10 seconds
You have taken a panoramic radiograph, the posterior teeth on one side are wider than on the other. What positioning error has occurred?
Patient rotated in machine
You suspect a root fracture after trauma to tooth 11, but the patient cannot tolerate periapical radiographs (due to shallow palate and gag reflex). What radiograph do you request?
Anterior oblique maxillary occlusal
What is the benefit of using a panoramic radiograph set to Orthogonal Program?
X-ray beam is closer to 90º to teeth
- reduces overlap of the teeth to aid assessment of INTERPROXIMAL CARIES
- improves angulation to more accurately represent INTERDENTAL PERIODONTAL BONE LOSS
You take a panoramic radiograph and on examination of it the incisor teeth are horizontally magnified. What positioning error has occurred?
Patient too far back in machine
What occurs if the Frankfort plane is not parallel to the ground during panoramic radiography?
Chin down = ‘smiling’ occlusal plane
Chine up = ‘flat’ occlusal plane
You take a panoramic radiograph and on examination of it the incisor teeth are horizontally narrow. What positioning error has occurred?
Patient too far forward in the machine
(incisors now buccal to the focal trough)
A fit and healthy patient presents to the surgery to have the surgical removal of a carious 48. Anatomically which nerves must be anaesthetised to remove this tooth safely?
- inferior alveolar nerve
- lingual nerve
- long buccal nerve
Give three clinical reasons that could account for neuro-sensory deficit after extraction of tooth 48:
- injury to the nerve (cutting or crushing)
- post extraction swelling/inflammation
- infection
Legislation in the UK has sought to ensure that all new dental practise premises are built to allow people with an impairment or disability equal access. Name two relevant Acts of Law:
- The Disability Discrimination Act 1995
- The Equality Act 2010
The definition of disability varies between the medical model and the social model. Briefly describe the difference between the two models in their definition of disability:
Medical model = focused on the limitations or impairments of the individual as a medical condition. Emphasis is on persons inability to perform certain activities etc
Social model = caused by the way society is organised, and barriers created that prevent people with disabilities from participating fully in aspects of life
You position a patient with cerebral palsy, which particular aspect related to his cerebral palsy may affect the dentists access to the mouth?
Uncontrollable muscle spasms and head/neck movements
What non-pharmalogical adjuncts are available to overcome uncontrollable muscle spasms of cerebral palsy patients and aid the dentists access to the mouth?
- finger guards
- mouth props to hold mouth open
List two medical aspects of Down’s Syndrome which may result in them having a lack of capacity?
- intellectual disability
- dementia
Considering the Adults with Incapacity (Scotland) Act 2000, list two differences between a Welfare Guardian and a Welfare Power of Attorney:
- Appointment = welfare guardian appointed by court of local authority whereas wellfare POA appointed by individual themselves while they still have capacity
- Scope of power = welfare guardian has broad powers to make decisions on behalf of person including personal welfare/finances/martial affairs. Whereas wellfare POA can only make decisions to individuals personal wellfare/medical decisions
List two features associated with Down’s Syndrome that are likely to contribute to periodontal disease development:
- systemic immunodeficiency and altered inflammatory responses
- impaired ability to self care included OH
List a management strategy for established osteoradionecrosis of the jaw:
Hyperbaric oxygen therapy (HBOT)
What is the bacterium associated with secondary endodontic infection?
enterococcus faecalis
What is the term for maintaining communication between the pulpal space and peri-radicular tissues?
Patency
How is facial palsy caused during LA deposition?
- Clinician doesnt hit bone & deposits LA too far back
- LA deposited into parotid sheath
- facial nerve runs through parotid sheath
- dense facia around parotid gland means LA stays for a long time
- causes paralysis of the muscles that the facial nerve supplies
Describe three differences between stroke and facial palsy?
- LA same side as injection, stroke presents on opposite side of lesion
- Can still wrinkle forehead and blink in Stroke
- Stroke typically only affects lower face and tongue
- Facial palsy affects all muscles on affected side
A patient experiences facial palsy after LA administration, name 4 ways in which you would manage this patient?
- reassurance
- provide eye patch to protect eye until blinking reflex returns
- give emergency contact number
- tell patient that sensation/movement will return after a few hours
What medications can cause xerostomia?
- tricyclic antidepressants
- anticholinergics
- diuretics
- beta-blockers
Give examples of psychiatric disorders:
- anxiety
- ODC
- bipolar disorder
- schizophrenia
- eating disorders
Name 2 cognitive tests for dementia?
- MMSE (mini mental state examination)
- Blessed dementia scale
Alzheimer’s patient enters your surgery, who can consent on behalf of them?
- welfare guardian
- welfare POA
- GPs/Dentists under act 47 of AWI
What are the factors of deprivation in relation to SIMD?
- income
- employment
- education
- health
- access to services
- crime
- housing
Give 3 study designs and explain them?
Cohort = Prospective, follow a group of subjects over a period of time & identify those that get disease/outcome. Used for incidence, causes and prognosis
Case control study = Retrospective, control group compared to a group with disease to see which has higher incidence of disease, looks at cause of disease
Cross sectional study = at a single point in time, exposure and outcome determined simultaneously to estimate prevalence and risk factors
2 types of e-cigarettes?
- disposable
- refillable and rechargeable
What advice should you give patients regarding e-cigs?
- the long term of e-cigs are largely unknown and may be more harmful than we know HOWEVER they are likely safer than conventional smoking
- for those trying to quit smoking recommend use of nicotine patches instead
- dont use if you havent smoked before
- try not to use in front of children as it normalises behaviour
What is the periodontal phenomenon experienced by smokers when trying to quit?
Increased inflammation of the gums caused by increased blood flow to gingiva causing
- redness
- swelling
- bleeding
- tenderness
What should consent be?
- valid
- voluntary
- informed
- not coerced
- not manipulated
- with capacity
What might be signs that a paediatric patient is nervous?
- wants to go to toilet a lot
- fidgeting
- hiding behind parent
- complaining of stomach pain
What is the fluoride regime for a high risk 4 year old?
1450ppm toothpaste
0.5mg fluoride supplement
What are the aims of suturing ?
- approximate tissues and compress blood vessels
- reposition tissues and cover exposed bone
- prevent wound breakdown
- achieve haemostasis
- encourage healing by primary intention
- prevent foreign bodies entering extraction space
Give 4 types of sutures:
Non-resorbable monofilament = prolene
Resorbable monofilament = monocryl
Non-resorbable multifilament = black silk
Resorbable multifilament = vicryl rapide
In oral surgery extractions that have turned surgical, what are the access fundamentals?
- wide based incision
- no sharp angles
- large flap heals as well as small
- incision done through to bone (cleanly in one stroke)
- minimise trauma to papillae
- avoid cutting through neurovascular structures
- no crushing of tissues
- keep tissues moist
What is meant by healing via primary intention?
One wound edge is next to another with no space, no waiting for granulation
what is the term used to describe a collective group of microorganisms in the oral cavity? What are they referred to when attached to a surface?
Oral microbiome
—> goes on to become biofilm once attached
What are the key microbial stages of caries plaque formation?
- adhesion
- survival and growth
- biofilm formation
- complex plaque production
- acid production
- caries
What are virulence factors that can apply to oral microorganisms to help them survive?
- adhesion factors
- enzymes
- toxins (eg P gingivalis produces gingipains which damage gingival tissue)
Why is it difficult to determine causality from a specific bacteria in endodontic infection?
- endodontic infections often caused by multiple microorganisms
- interactions between different bacteria in endodontic infections can be complex and may involve synergistic and antagonistic relationships
- host response to endodontic infection differs in each host
- diagnostic techniques are limited
How do S. Mutans;
- survive in high acidic environments
- stick to each other
- production of extracellular polysaccharides (EPS) which form a matrix that helps protect bacteria from acid
- acts as a buffer neutralising the acidic environment
- also helps retain nutrients needed for bacteria growth
- adhesions via surface proteins that are able to recognise and bind to specific sugar molecules (sucrose and glucose)
What anatomical feature is responsible for discharging pus from a tooth (eg 26)?
Sinus tract (fistula)
- opening formed as a result of the body’s immune response to infection
- WBCs and immune cells accumulate in the area leading to formation of pus
- over time the pressure of pus can cause tissue damage and create a pathway (sinus tract)
How can a mold liner help with gaseous porosity of PMMA?
A mold liner is a material that is placed inside a mold cavity to improve the surface finish and to reduce the formation of defects such as gaseous porosity:
- provides a smooth surface for the PMMA to flow against to prevent formation of air pocketing
- improves thermal conductivity of mold which helps to reduce cooling time
Give 4 properties of impression material being sent for off site lab construction:
- able to decontaminate
- dimensionally stable outside mouth
- compatible with cast material
- non-toxic/non-irritant
Name 3 materials used for post-core crowns?
- ceramic
- low gold
- high gold
- NiCr (nickel-chromium)
Name 3 types of post which can be used:
- serrated, smooth, parallel
- tapered or parallel
What name is given to the residual collar of dentine required before placing a post?
Ferrule
How much GP should be left in the canal space when placing a post?
4-5mm
Give the width of taper required for a MCC:
6º
Would you expect tooth mobility to increase or decrease in a patient with moderate advanced periodontal disease, following PMPR? Explain why:
Decrease in mobility
- gain in clinical attachment
What percentage of people are affect by sensitivity after teeth whitening?
60%
Give 3 predisposing factors likely to cause sensitivity post-tooth whitening?
- gingival recession
- previous sensitivity
- concentration of H2O2
External cervical resorption may occur in patients that receive tooth whitening, what is the method of action of this?
H2O2 diffuses through dentine to periodontal tissues and cementum and causes oxidative damage which triggers an inflammatory response to cause destruction
Why can root resorption occur following tooth whitening?
- pre existing/previous dental trauma
- too high concentration of peroxide
- overuse of products
Give 3 reasons for non-surgical periodontal treatment before surgical:
- assess patient motivation
- non-surgical treatment may reduce some deep pockets
- less invasive and can stabilise margins before surgery
3 indications for surgical periodontal treatment at re-evaluation?
- re-evaluate after 3 months
- residual pocketing >6mm
- excellent OH
Give 3 supportive roles of GDP after surgical periodontal treatment carried out by perio specialist:
- maintain good OH
- carry out routine PMPR
- monitor disease and review
- encourage
What group does Chlorhexidine belong to?
Biguanides
What is a common site effect of the drug phenytoin? Give 2 drugs which also cause this side effect:
Gingival hyperplasia
- cyclosporin
- nifedipine
How can gingival hyperplasia be treated?
- localised PMPR
- gingivectomy
What problems surround and limit usefulness of antibiotics in treating periodontal disease?
- resistance
- superinfection
- biofilms resist antibiotics
- may stimulate allergic reactions
What anatomical features should be captured on a maxillary impression for removable prosthetics?
- coverage of maxillary tuberosity
- hamilcar notch
- extension posterior to vibrating line
- functional depth and width of sulcus to create peripheral seal
What anatomical features should be captured on a mandibular impression for removable prosthetics?
- pear shaped pads
- buccal shelf
- retromolar pad
- extension into lingual pouch and mylohyoid space
- functional width and depth of sulcus
What are features that help mark the posterior border of an upper denture?
- vibrating line
- 2mm infront of palatine fovea
- level of hamular notches
What material should be used for maxillary and mandibular secondary impressions? (2 marks)
Upper = alginate or addition silicone
Lower = addition silicone
What are 2 factors that affect physical retention of a denture?
- muscle tone of buccinator and orbicularis oris
- depth of sulcus
What is the best type of post to use and why?
Parallel post better than tapered as:
- more retentive
- less likely to cause root fracture as load not dispersed horizontally
What orthodontic appliance should be prescribed to correct an anterior crossbite?
- 12; Z-spring; 0.5mm HSSW (active component)
- 14,24,16,26; Adam’s clasps; 0.7mm HSSW (retentive)
What orthodontic appliance should be prescribed to correct an posterior crossbite/expand upper arch?
- Midline palatal screw (active component)
- 14,24,16,26; Adams clasps; 0.7mm HSSW (retentive)
- Posterior bite plane (PBP)
Give 3 ways the dose to the patient is reduced by normal radiographical techniques?
- rectangular collimation
- film speed
- distance from beam
Describe the process of compton scatter in radiography and how it differs from the photoelectric effect:
COMPTON SCATTER
- incoming X-ray photon interacts with an outer shell electron in the atom, transferring some of its energy to the electron and causing it to be ejected
- the photo itself is scattered in a different direction with reduced energy and can then interact with other atoms in the object
PHOTOELETRIC EFFECT
- incoming X-ray photon interacts with an inner-shell electron in an atom causing the electron to be ejected from the atom
- photon is then completely absorbed by the atom leading to production of an image
By what mechanisms does topical fluoride prevent caries? (4)
- Formation of fluoroapetite which is more acid-resistant
- Fluoride promotes remineralisation of tooth enamel by enhancing mineral uptake (calcium and phosphate)
- Inhibition of bacterial enzymes so reducing ability of bacteria to produce acid
- Interferes with biofilm formation
What dose of fluoride tablet would you give a four-year-old at high risk for caries with <0.3ppm fluoridated water?
0.5mg daily
What is the rationale behind antibiotic use in periodontology?
- Used alongside mechanical treatments eg PMPR/root planing
- Used for aggressive periodontitis or NUG/NUP
- Reduces bacterial load in pockets and can help prevent spreading systemic infection
- Should not be overused and mechanical should always be considered first
What problems limit antibiotic usefulness in periodontal treatment?
- Antibiotic resistance
- Negative side effects or allergy
- Limited penetration into periodontal tissues
- Lack of evidence that it works
In what situation would it be appropriate to prescribe systemic antibiotics in periodontal therapy?
- patients with acute necrotising periodontitis
- chronic periodontitis that has not responded to mechanical therapy/PMPR
- young people with grade B or C (agressive)
- patients with periodontal abscesses and signs of spreading systemic infection (malaise or fever)
Briefly describe the steps in obturating the canal of an upper central incisor: (6)
- dry wet canal with paper cones/points
- drop master cone into canal & beck for tug back
- once happy apply sealant to master cone and place into canal
- use finger spreader to make room for gutta-percha cones
- place sealant covered GP cones into canal until full
- remove excess from cavity/pulp chamber with Super Endo Alpha and seal
Which part of root canal filling is most important to long term success?
Coronal seal restoration
What is the minimum data set to be recorded on the record block?
- midline
- canine line
- smile line
What are the normal dental and occlusal features that you would expect to find in a 10-year-old child?
- tooth wear on deciduous teeth
- canines palpable buccally
- absence of spacing
- mixed dentition
- no cross bites
- incisor class I
- molars tend to be slightly class II due to relatively large size of lower Es
Name three materials used for crowns:
- Zirconia
- Ceramic
- Stainless steel
- Gold
- Metal ceramic (CoCr)
What is the disadvantage of using a tapered post?
Causes “wedging” which can lead to root fracture
Give three measurements to consider when deciding which post to use?
- at least 1.5mm height and width of remaining coronal dentine
- root filling length should be 4-5mm root filling apically
- no more than 1/3rd of root width at narrowest point
what does the residual ridge anatomical feature supply to a denture?
support
what does the hard palate anatomical feature supply to a denture?
support
what does the post dam anatomical feature supply to a denture?
retention
What is the biological width?
Combined thickness of connective tissue and junctional epithelium
- usually 2mm
Chlorhexidine is commonly used for periodontal disease treatment, name three other indications:
- patients with candida infections
- necrotising ulcerative gingivitis
- after luxation injuries
Name one of the two recommended doses of chlorhexidine:
10ml of 0.2%, 2x daily
How is chlorhexidine efficacy deminished by the patient?
- if used with toothpaste in the mouth it will be inactivated
- poor compliance due to taste
Name the surgery used to repair cleft lip and palate:
Orthognathic surgery
Following hygiene phase therapy this patients oral hygiene was excellent but pockets of >5mm persisted in the lower left quadrant.
Suggest FOUR appropriate treatment options for this quadrant now:
- Repeated non-surgical periodontal therapy (PMPR, subgingival scaling & root planing)
- Adjunctive therapy with antimicrobials
- Periodontal surgery (eg flap surgery)
- Maintenance therapy (perio evaluations, scaling etc)
What are two safety features of amalgam container?
- leak proof
- mercury vapour suppressant in the lid
What licence is required for the disposal of amalgam and how long are the record kept?
- Consignment note
- 3 years
What problems arise if a post is too narrow?
- insufficient retention of core
- post removal may be harder
Give examples of two health promotion approaches to reducing smoking in Scotland:
- restricted marketing and sale of cigarettes (plain packaging)
- cigarettes must be hidden behind counters in shops
- banned smoking in most public places
What margin design would you use for the labial crown prep on an incisor ?
- 1.5mm reduction
- Shoulder
What benefits are there to shoulder margin designs in incisal crowns?
- maximum aesthetic contours
- reduced risk of marginal breakdown and resistance to occlusal forces
What is the ideal margin design and reduction for palatal prep of an incisor for a metal ceramic crown?
- 1.5-2.0mm reduction
- Chamfer margin
What are the benefits of a chamfer margin design?
- reduced fracture risk
- more accurate marginal fit, ensuring good coronal seal
What type of anchorage is in a posterior crossbite component? How would the baseplate be modified for this?
Reciprocal anchorage
- angle the cut in the baseplate
What could you add to an URA to stop thumb sucking?
Palatal thumb crib habit breaker
Which impression material would you use for a custom tray with 3mm spacing and why?
Alginate
- requires more spacing due to having a lower tear strength
How can candida become anti-fungal resistant?
Formation of dual species biofilm with S. Aureus provides a polysaccharide matrix
Two key features that enable caries bacteria to adhere and survive in acidic environments? (2 marks)
- Glucan adhesive molecules (to help stick and form biofilms)
- ATPase proton pump to remove hydrogen ions from the cell to maintain neutral internal pH
Give three ways in which the pulp communicates with the PDL: (3 marks)
- Via apical foramen
- Via accessory canals
- Via dentinal tubules
What are the principles of waste disposal according to SDCEP?
- minimise waste generation
- segregation
- safe handling and storage
- labelling
- disposal
- good record keeping
What are the short and long term consequences of overhang restorations in dentistry?
SHORT TERM
- food trap
- irritation of soft tissues
- occlusal interference
- plaque retentive factor
- difficulty cleaning
LONG TERM
- marginal breakdown
- periodontal disease
- secondary caries
- gingivitis
- tooth fracture / restoration failure
What is meant by springiness?
A materials ability to undergo large deflections without permanent deformation
What regulations control waste disposal?
- Health and Safety at Work Act 1974
- Medical Device Regulation (MDR 2017)
- SHTM (scottish health technical memorandum)
- COSHH 2002
