Last God exam questions Flashcards
How would you chart bitewing findings?
- Specific location (start with alveolar bone)
- Radio-opaque or radiolucent
- Extent
What is a material risk? How do we manage it?
A material risk is a significant risk that occurs regardless of frequency of the procedure. Such risk could be exposing patients to radiation who are pregnant
What are the steps to radio-graph assessment?
- Exposure
- Detector orientation
- Horizontal detector positioning
- Vertical detector positioning
- Horizontal beam angulation
- Vertical beam angulation
- Central beam position
- Colimator rotation
- Sharpness
- Overall diagnostic value
What are the steps to gingival assessment?
C - colour
C - contour
C - consistency
T - texture
E - exudate
What is the difference between sign and symptom?
Symptom - are reported by the patients
Signs - are detected by the physician
What are the steps to ILA?
- Patient
- CC
- MHx
- SHx
- DHx
- Exam
What is empathy?
It is the ability to understand and share other people’s emotions.
What is the cultural iceberg?
It is a visualisation diagram that allows us to understand the concepts of deep and surface culture.
Surface culture could include: Language, holiays and festival and literature
Deeps culture includes: gender norms, understanding of self and allowed autonomy
What is TRIM?
TRIM is an acronomy for:
Timing
Relevance
Involvment
Method
What is differential diagnosis?
It is a process where a physician is able to assign probability of one illness in comparison to others accounting for patients sympotms.
What is a white spot lesion?
A white spot lesion is an incipient caries lesion, it has a dull opaque chalky appearance and occurs due to demineralisation of enamel caused by cariogenic bacteria
What is the pathogenesis of caries?
- Cariogenic bacteria requires simple sugars for anaerobic respiration
- Glucose is processed through glycolysis in the cariogenic bacteria
- Glucose is converted into 2 pyruvate
- In order to than convert NADH electron carrier into NAD+, pyruvate is converted into lactic acid
- Lactic acid accumulates in the cariogenic bacteria and is released into the oral environemnt
- Lactic acid has pH of about 2.35 which is slower than the critical pH of hydroxyapatite which means Lactic acids is able to cause dissociation of hydroxyal groups in hydroxyapatite which leads to demineralisation of the enamel
How can we remineralise a tooth?
In presence of Calcium, Phopshate and/or Fluoride in the biofilm or in salivary pool, if pH of above 4.5 is restored the tooth would be immediatley remineralised
What is the significance of dental pelicle?
It is able to provide some protection to the enamel. It also allows for binding of bacteria to the surface of the tooth
What is the significance of biofilm in demineralisation?
Biofilm and calculus are able to create a more closed system where buffering agents from saliva are unable to penetrate, this may cause more demineralisation as lactic acid produced by carcinogenic bacteria is not buffered
Why is brushing so good for caries prevention?
Brushing:
- removes biofilm
- introduces more fluoride for remin
Why is fluoride so effective?
- It is able to stop cariogenic bacteria metabolism
- Drive remin
- Create fluoride salivary pool
Why are incipient carious lesion look so much opaque?
Due to increased porosity. Increased posicity of enamel traps water which has a different refractive index which makes it look more dull
Why is calcium still needed for fluoride incorpiration?
Fluoroapatite still needs calcium and phosphate
How would you describe WSL
L - location
C - colour
T - texture
C - contour
What is stephan’s curve?
It is a graph that shows what happens with oral pH after sugar consumption
What would your brushing instruction would be for a person between ages of 0-1.5
No fluoride
What would be your recommendation for an individual 1.5-6 years old for brushing?
- Low fluoride tooth paste to minimise fluorosis
- peasize
- Supervised
- Spit not rinse
What would your recommendation for an individual 6+ years old?
- Standard dose fluoride
- Peasize
- Spit not rinse
- Supervise if needed
How is calculus formed?
- Acid attack occurs
- Statherin releases Ca
- Excess calcium is able to percipitate on the biofilm as it can be used as an epitatic agent
What are the steps to rubber dam application?
- Tooth assessment and tooth prep
- Clamp selection and preparation
- Dam preperation
- Clamp placement
- Clamp and dam placement
- Anchorage
- Dam Frame
- Inversion
- Finishing
- Removal
What are the steps of rubber dam applicaition and removal?
- Prepare rubber dam equipment
- Assess tooth to be clamped
- Prepare the rubber dam
- Floos up the clamp
- Try clamp onto tooth
- Apply rubber dam and the clamp
- Put the frame on
- Invert the dam
- Cut the inteproximal spaces
- Remove the dam and clamp
- Floss the rubber in the interproximal areas
What are the steps of rubber dam critique?
- Dam preperation (hole positionin, punching)
- Clamp selection (choice, gingival trauma, retention)
- Clamp placement (gingival trauma)
- Dam placement (alignment of dam)
- Frame placement (positioning of frame)
- Dam finish (isolation of appropriate teeht, moistture control)
- Dam removal
What are some of the other methods of moisture control?
- Retraction
- Cotton rolls
- Triplex
What is an ecological niche?
It is space where some organisms are able to thrive in, such are present in oral environment on tooth surfaces, calculus
What is utilitarianism?
It is basically - greatest happiness for the greatest number. Most benefit = the best route
What are the four classic biomedical principles?
- Non-maleficence
- Beneficence
- Autonomy
- Justice
What is non-maleficence?
Cause no harm. Donwside: harm could be unavoitable and uncotrolled
What is justice?
Justice is giving another their due/what they are owed.
What is pubic health?
It is response of society to protect and promote health and to prevent illness
What is lifestyle approach?
It essentially based on the idea that healthy behaviours are shaped by social environment
How do we achieve haemosatasis in 4 steps?
- Vascular spasm/local vasocontriction - the cut vessels immediately contrict to slow blood flow and minimise blood loss
- Formation of a platelet plug via adhesion, activation & aggregation of platelets:
a. von Willebrand factor adheres to the exposed endoepethilial collagen, creating sites which allow platelets to bind forming a platelet plug - than platelets release factors that aggregate other platelets
b. Thromboxane A2 - major component produced by platelets - involved in platelet aggregation adn vasocontriction
c. ADP is also produced by platelets - it stimulates release of prostocyclin and nitric oxide which can limit platelet aggregation - platelets plug size control - Blood coagulation = transformation of blood from liquid to solid gel
a. Platelets are stimulated to relase prothrombin activator which converts the plasma protein prothrombin into the enzyme, thrombin
b. Thrombin converts the plasma protein fibrinogen into threads of the protein fibrin which wind around the platelet plug to form a framework of fibres - this holds the plug and other blood cells in the blood vessel
c. Platelets in the clot begin to shrink - tightening the clot - Clot dissolution occurs via:
a. TPA, a protein on endothelial cells activates the conversion of plasminogen to plasmin
b. Plasmin breaks down clots by breaking down the fibrin netwrok
c. Macrophages & phagocytic WBCs then phagocytose the debris
What is the pathogenesis of erosion?
- Intrinsic acids from gastroesophageal reflux or extrinsic acids from diet, medication or other sources enter the oral cavity.
- Acids wash away dental biofilm and the dental pellicle and land directly on the tooth surface.
- Acids reduce the pH of the oral environment below the critical pH of HA (5.5) or FA (4.5) and cause demineralisation of enamel to form Ca & PO4 ions. Enamel rods are permanently shortened
- As erosion occurs in an open system (as there is no biofilm to trap mineralisation products), mineralisation products are washed away or swallowed and there is no future potential for remineralisation.
What are the steps of CD4+ cell activation process?
- Foreign antigen phagocytes, killed & processed by the APC
- ACP presents processed fragment
- This is done via MHC II molecule (epitode) on the membrane surface of the APC
- Epitode binds with TCR on naive CD4+ T lymphocyte
- This causes activation of the naive CD4+ T lymphocyte and creates a T helper cell
- T helper is able to bind with a B lymphocyte and cause it to transform into either B memory cell or plasma cell
What are the steps of Type I hypersentivity?
- Antigen is processed as usual and Plasma cells are created with a speicifc IgE antibody
- IgE antibody binds with a mast cells and act as a receptor
- If the antigen apprearce again and binds with IgE receptor on the mast cell it will cause degranulation
What are the 5 steps of inspiration?
- Diaphragm and external intercostal muscles contract
- Thoracic cage expands up and out
- Lungs expand
- This causes a drop in intrapulmonary pressure
- This cause a drop in intra-alveolar pressure thus movement of air from the atmosphere to the alveoli
What are the 6 steps of expiration?
- Diaphragm and external intercostal muscles relax
- Thoracic cage moves in and down
- Lung’s recoil toward pre-inspiratory size
- Air in lungs compressed
- Pressure rises above atmospheric
- Air flows out of the lungs down the pressure gradient
What is surface tension?
Surface tension is a force that make it hard for the alveoli to expand. Basically there are water molecules on the epithelium lining of the alveoli which create the “air-water interface”, but those water molecules are more strongly attracted to each other than the air thus are able to resist the pulling apart while the alveoli expand.
How can we overcome the surface tension?
Through use of a surfactant released by type 2 alveolar cells. Surfactant can be released through tubular myeline. It reduces the attraction between the hydrogen bonds of the water molecules thus reducing their resistance to separation while the alveoli expand resulting in an increase in pulmonary compliance.
What is compliance?
Compliance is the effort required to expand the lungs. Some factors may reduce compliance thus making is hard to breathe. Some things, such as elastic connective tissue that facilitate alveolar recoil, increases elastic compliance.
What are the 4 steps of buccal stage?
- Compression of the bolus against hard palate
- Retraction of the tongue forces bolus into the oropharynx
- Elevation of the soft palate seals off the oropharynx
- Once bolus enters the oropharynx, reflex response are initiated and the bolus is moved towards the stomach
What are the 4 steps of pharyngeal stage?
- Tactile receptors on palatal arches & uvula are stimulated
- Pattern of muscle contraction in the pharyngeal muscles is triggered by th swallowing center in the medulla
- Elevation of the larynx & folding of the epiglottis results from contractions of the pharyngeal muscles
- Pharyngeal constrictors then force the bolus thru the pharynx, past closed glottis and into oesophagus
What are the 6 steps of orhostatic hypotension?
- Blood is evenly distrivuted through the body when lying flat
- On standing blood pools in the legs due to contraction of skeletal muscles and squeezing of veins
- Pooling blood cuases reduction in venous return, this causes the reduction in cardiac output, reducing blood pressure
- The body is unable to appropritley regulate it due to multiple factors
- Reduced pressure to the brain causes the brain to shut down due to lack of oxygen
- Person falls
What are the steps to fissure selant placement and what are their reasons?
- Moisture isolation – salivary contamination and easier access
- Clean the surface of plaque/debris – if the debris is there fissure sealant won’t bond
- Rense the tooth and dry – remove debris and tooth needs to be dry
- Etch – phosphoric acid remove pellicle, remove old enamel surface, increases surface area by creation of porosities thus creating micromechanical bonding
- Rinse tooth – stop etching process and remove enamel products
- Dry tooth – remove debris and tooth needs to be dry for bonding
- Apply the fissure sealant to the etched surface
- Probe the entire surface in order to check for potential imperfection – make sure the fissure sealant does not create niches for bacteria to accumulate
How can we calculate the GFR?
By using substances that can be freely filtered and not at all resorbed. SUch substance is creatinine - a bi-product of muscle metabolism.
What s the formula for GFR?
GFR = (urine concentraion x urine flow)/plasma concentration
What are podocytes?
They are cells that cover basal lamina of the bowman’s capsule
How can podocytes function?
The movement of actin like filaments allows them to increase their size, constrict the area of filtration thus reduce GFR
What is a tubular maximum reabsorption?
It is a theoretic process in which active transport mechansism can reabsorbed substances at max. Beyond tubular maximum reabsorbtion rate can not increase and surplus of materials is lost in urine.
How does diabetes mellitus relate to maximum tubular reabsorbtion?
Diabetes mellitus is a condition where there is a large amount of glucose in blood.
Upon filtration in the glomerulus it is released in the tubular system.
Due to high amounts the glucose excides the maximum tubular reabsorption rate thus is excreted in urine.
This cause a shift in osmotic pressure against reabsorption thus increasing the urine volume.
Thus the thirst is increased.
Outline once again the cosntant and variable Na+ reabsorptions in the tubular system of the nephron.
Constant:
- Proximal tubule 65%
- Ascending loop of henle 25%
Variable:
- Ditant convoluted tubule and collecting 0-10%
What is the importance of sodium in relation to water?
High sodium load = increased water reabsorption
WHat are the three mechanisms of rening release?
- Baroreceptor like - granular cells can act as baroreceptors
- Stimulation from macula densa cells that detect changes in salt in the distal tubule
- SNS signalling
What is the mechanism of renin?
Renin works via RAAS system to increase Na+ reabsorption
What is the mechanism of work of aldosterone?
Aldosterone is part of the RAAS and increase the reabsorption of Na+ by kidneys.
This changes the osmotic pressure to hold more water.
Thus increasing blood volume.
Increasing blood pressure.
What is the mechanism of work of angiotensin II?
Angiotensin II triggeres the relaaese of vasopressin by the posterior putunitary gland.
Vasopressin is able to increase the water reabsobtion in kidney tubules by binding to type 2 vasopressin receptor and increasing the work of aquapourins 2 and increasing there number in the collecting duct.
How do ACE inhibitors help with regulation of hypertension?
ACE is a hormone that converts Angiotensin 1 into Angiotensin 2 trigeering aldosterone releae and vasocontriction.
IF ACE is blocked, angiotensin 1 can not be converted into angiotensin 2 thus it is undable to cause vasocontriction and increase sodium retention.