Diagnosis Of Endo

[Music] hi vanessa this is dr srikanth from team mds conquer uh now we are going to start endodontics uh this first content i'll be discussing very important aspects about the topic diagnosis okay and this topic diagnosis will cover diagnosis from all the aspects like diagnosis of almost all the subjects directly or indirectly so the first important aspect in the diagnosis is you need to make a note about the symptoms okay so coming to the symptoms so we have two symptoms one is subjective and second one is okay so one is subjective and second one is objective most of the subjective symptoms are they'll be uh given by the patient okay so in the form of an information so they will be given by the patient and coming to the objective symptoms the objective symptoms are will be known by the dentist by using some uh like tests or with some basic information okay so that is the subjective subjective are basically they are given by the patient whereas coming to the objective part objective part will be taken by the dentist by various tests or exams so that is about the symptoms and coming to the subject the most important subjective symptom that is given by the uh patient in the dentistry is pain okay hope you know okay so pain and pain is basically due to nose and you know that enamel an animal is the one that doesn't have any nose any nose in it okay so most of your nerve related pain is due to basically due to the and i have clearly uh given you the clear-cut idea like how uh i mean what are the nerves that are present in the body and what are the nerves that are present in the dental pulse in my video which is in the medicine physiology part that is the classification of now so i don't want to talk anything related pains of dental origin okay pains of dental origin will be on the same side that is the ipsilateral side and will never never cross the midline okay so that's that's very important thing so for your information sake i have uh i have added this particular slide which contains the information of the nerves that are present in the pulp so as already discussed the predominant nouns are present in the pulp are a delta and the c fibers okay so all these points of a delta and c fibers are very very very important in examination point of view okay so you can pause the video and just check all the all the points that is the diameter conduction velocity where they are present okay what is the mode of pain they carry and all these are very very important points to be added okay so next comes is as already as already discussed the symptoms are of subjective and objective and subjective comes uh i mean like most of your subjective signs are related to the pain and coming to the next part that is the object or objective you know need you you need to go with the few examinations or few tests okay in that the first test we're going to talk about the percussion okay so this is a percussion test so percussion uh is a one that is going to like how well uh we are responding to the percussion test gives an idea about the degree of the inflammation that is associated so one percussion test that is most commonly used i hope most of you are very very uh familiar with this with this that is called as tooth sloth okay ah it is also called as rubber wheel test okay so they use they use rubber wheel here similar to this is a tooth slot okay or it can be called as bite test you'll ask the patient to bite on this cloth whenever the patient responds positive okay so whenever patient responds pain upon biting then you can diagnosis it as epical periodontitis means inflammation at the apex and whenever the patient is negative means not negative exactly it is whenever the patient has a relieve of pain okay when the patient has a relief of pain then you can diagnose it as crack to syndrome okay so that's very important uh things to be added related to this particular test okay this test is also called this tooth slot test or rubber wheel test or a bite test whenever you have pain on bite that is called as epical periodontitis whenever you have relief of pain on the bite then that is called as crack tooth syndrome the next comes i hope you know this this is called as palpation okay palpation can be done at different areas okay most of you are familiar with different types of palpations external palpation you will have your lymph nodes will be palpated internally or periapical area the vestibular areas are palpated whenever you have a or tenderness you can diagnose it as an uh acute inflammation case like you can diagnose it as an abscess or something so you need to pulp it so what are the futures of palpation so whenever you have an acute infections okay whenever you have an acute infections uh the palpation signs will be tender the patient will have pain and sometimes it may be mobile okay and they are enlarged okay so these are the acute signs and when coming to the chronic signs what happens in the chronic situation in the chronic situation they may not be tender it is non-tender okay it can be mobile and it can be enlarged so when when you take tb into consideration like tuberculosis lymphoids okay ah i hope you remember when we were talking about this we are going to talk or we were done with the talk about this related to the tb lymph nodes they are matted lymph nodes means a pack of group of lymph nodes so they can be called as matter lymph nodes they are not tender you don't have any pain okay so such category of lymph nodes that comes under the tv lymph nodes or like they can ask you the the the node that is going to infected when a particular teeth is associated with the okay we we're going to learn about this in space infections in the in the oral surgery but just like for example if it is a lower anterior teeth your submental lymph nodes are going to be palpated or inflamed okay if it is like a posterior teeth okay if it is like posterior maxillary teeth posterior upper teeth your sub maxillary lymph nodes are are infected or or palpated okay so basing upon this you're going to change which type of lymph nodes and everything so this is how the external palpation is done internally that is vestibular and vegetable attendance we call it as external this is how the lymph nodes are palpated and different different lymph nodes palpation will give an idea that this teeth may get infected okay right so clear right the next comes is some radiographic information is again required mostly uh as per the uh i mean like as per the suggestions you need to take a minimum uh two views of the same date same date okay so that you can you can you can change the angulation by which you'll get to know like what are the things that are associated with the particular abnormal you can see here the difference in the normal pdl okay this is a normal pdl okay whereas here you can see the laminar juror whereas whenever you have a periapical infection okay so you can see that there is widening the pdl space is being widening you can see the widening medial space here whereas here you have a normal pdl space and you can see the loss of laminate whereas an opaque layer is clearly visible here here you don't have any opaque layer okay you can see the loss of laminate so loss of laminar juror is one of the most common sign that is seen uh whenever whenever the infection is infection is going to start like the first sign that seen on the radiograph and what you can appreciate is loss of laminar juror the epical reason okay so i mean this is again a radiology related stuff this is called as inverted y shape hope you remember inverted inverted that is called as inverted by line of ins inverted by line of ins that is called as that is nothing but an overlapping border of the nasal flossa and the maxillary sinus okay so there is an overlapping of this is a maxillary sinus this is in a nasal fossa both are overlapped to form a y line inverted violin okay this is preferably seen at the maxillary canine area okay so a radiology related stuff just for the information sake i added here okay the next comes is i mean regular things i don't want to discuss much okay a bitewing bite wing bite wing radiographies of less use in end why because you need a periapicalarian bite wing you don't get the periapical area most of your infections will be associated with the periapical region right so bitewing of less use in indo iopa is useful more okay so techniques like this technique is the slob technique same side same side lingual opposite side buckle okay that is that's what the slob rule says and you're very familiar we have we are going to discuss this much detail when we are talking about oral radiology uh and and the slobber is also called as cone shift rule because by shifting the cone if the object is moving on to the same side then that the object will be present on the lingual side and if the object is moving towards the opposite side in the direction of the cone shift then it will be present on the buccal side that's what the buck cone shift technique says that other name is cone shift technique or it can be called as tube shift technique tube is nothing but cone right you have a tube in x-ray film so that is going to you're going to change the direction of the tube that is called as tube shift technique it's also called as clark's technique it also called as buccal object rule technique okay so these are the other names of the slob technique okay so that's important thing to be added and there is one more variation which is exclusively used in endo uh that's a slob variation this is a very simple technique where you are going to change the angulation of the cone by 20 to 30 degrees okay so in this voltron's technique what you're going to take you're going to expose it then you're going to expose your cone at a particular angulation then you change the angulation then you change the angulation by 20 degrees okay to this angulation so by changing the angulation by 20 to 30 you're going to expose again so you'll have a two x-rays at a different angulation so the change of x-rays this technique is called as wall trans technique you can see in this radiograph if you see in this pic you have how many uh you you have inserted four four four files that is different scenario but on the radiograph what happens is they are overlapped they are overlapped right so you can see two canals only officially okay but when you change the angulation by 20 degrees to 30 degrees okay you will not see any overlapping you can see all the four channels this change in the angulation and this technique is called as a wall turns technique nothing but a similar pattern of slobs technique but it's more often called as the altrans the technique okay so uh you can apply the slop technique or there is something called as uh the other technique called as mbd rule okay so the nvidia rule ambitious is very very simple that is ingalls mbd rule any of these techniques the the the main mode of the outcome is the same means you're trying to change the angulation uh by which you are overcoming this overlapping of the canals or the overlapping of the roots by which you will get more information about the anatomy so next comes again this is the most commonly asked question so whenever you observe a radiograph okay or you observe a canal whenever there is a sharp change in the radiolucency within the canal then you can call it as a fast break okay so what fast break gives an idea the fast break gives an idea that single canal has changed into i mean is branched okay so you can predict one more channel okay you can whenever you for example you can see here there is a good uh radio lucency but suddenly the radial lucency has dropped here suddenly there is sudden drop in the relationship and similarly here also you can see radiation is good here but if you see the radiation has dropped here so sudden change in the radial lucency within the canal or sudden change in the density within the canal will definitely give us an idea or prediction that there may be some additional canal extra cannot extract canal okay so that is called as fast break one more important aspect that you have to make you not when we are talking about the radiology related stuff okay so this is a most of your familiar most commonly you will encounter this in your period that is called as classification of fercation okay classification of for occasions so this is called as a glickman's classification so glickman has divided into class one class two class three and class four most of you are very familiar with this okay so uh i mean like uh the the forcation probe cannot enter the furcation area okay so basically when you when you try to probe it the furcation probe will will not enter the forcation area that is about your class one ah and then in the class two the probe is able to partially enter the furcation and it extends approximately one third of the width of the tooth but it is not able to pass completely through the vacation that that is called as cluster first it it doesn't enter second it enters partially the next comes is the third one ah third one is the function uh the furcation i mean here it's not entering partially it's going to enter it's going to enter and that's what the difference and it's if you see the mandibular molars and the maxillary molars uh the probe that passes between the mesobuccal and the disturbance root and touches the parallel root that's in the maxillary and in the mandible the probe passes completely through the furcation between the mesial and the digital roots in the case of mandibular molars and coming to the fourth one the fourth one is same as the third one except the entrance of the forcation is visible clinically with a gingival region here it is not visible clinically but it moves from here to there here it is visible clinically and it moves from here to there so that is the difference between the four classes of furcations here it will not go here it will go partially here it goes completely here it glows completely which is visible to you clinically okay so these are the four classes of furcations that you have to make a note the next comes is the the testing the pulp vitality like more familiarly they are called as pulp sensibility tests okay what are these called as pulp sensibility test they are called as pulp sensibility test okay that is cold test these are called as thermal test cold and heat an electrical test that is called as ept so coming to the okay so in the thermal test you have cold test and the second one you have the heat test okay so coldest heat test and i hope you are very familiar with the coldest and heat test whenever you are doing a cold test on a heat test make sure you take a control teeth okay so your control teeth is going to be the adjacent and the contralateral tape okay so that's the question again the control teeth is the adjacent and the contralateral teeth and whenever you talk about this cold test or a heat test the most commonly asked questions for you is the temperatures okay these are the different temperatures which i have collected personally okay so the heat test the most commonly asked question is the temperature that is used in the heat test is 65.5 degree centigrade and most commonly asked question is carbon dioxide snow or dry ice the temperature is minus 78 degrees centigrade eyes well known that zero degree centigrade indo-eyes is minus 30 degree centigrade so most uh most of your clinical scenarios they they give invoice okay the wording they give is they give they talk about the indoors okay and carbon dioxide's noise is is a is a thing that is regularly used in case of your crowns full crowns you'll have full crown so heavy restorations where you can use carbon dioxide snow that is minus 78 degree centigrade so they can ask you blood is stored at the temperature of other fecular question when when you're talking about physiology that is four degrees centigrade they can ask you the platelets are stored at a temperature of platelets at regularly stored temperature of room temperature that stored at room temperature so the room temperature is 20 to 25 degrees centigrade so they're gonna ask you oral polio vaccine is stored at a temperature of minus 20 degree centigrade freezi dent okay is again is an eigen type of uh i mean the cold test that is the temperature is minus 20 degree centigrade okay so please do make a note about these values uh regularly as you can see questions regularly on this numerical system the next comes i was talking about the ept that is electrical pulp test okay there are different types of uh electrical pulp tests uh that are that are regularly used okay so i mean like the important points that we have to make a note when you're talking about the electrical pulp test is uh it is basically uh the basic mechanism is you're going to give some electrical excitation for the neural elements that are present in the pulp a positive response indicates the presence of nerves okay and a negative response indicates the vitality so whenever you have positive response you can you can you can you can you can predict it as a vital pulp a kind of vital valve a negative response or no response is a non vital a non-vital part okay so that that is the utmost important point that you have to make a note when we are talking about this particular thing okay so what happens in the next level uh the next level is so most of your questions will move around like uh the electrolyte because whenever you go over epd you need to apply electrolyte i hope most of you have done this uh in your colleges okay so uh the electrolyte you have to use a i mean like toothpaste okay so the toothpaste is called as grossman's toothpaste and you regularly used a colloidal graphite colloidal graphite is regularly used as an electrolyte in this situation and make sure whenever you do this particular type of ept make sure make sure that you don't don't wear glove okay because glove is going to act as a non-conductor it doesn't conduct okay so circuit will not be formed so make sure whenever you do this particular test on the patient don't wear a glove because through your body the circuit is going to form and make sure ept is contraindicated in the patients with cardiac trace macros so it's not it's contraindicated with the patients having cardiac pacemakers even your cardiac pacemakers it is contraindicated even your epics locators even your epics locators because apex locators are also therefore they work with the formation of a circuit so even your apex locators are contraindicated whenever you have whenever the patient is having the cardiac pacemaker so it's very very important your apex locators as well as your electrical pelvis are contra indicated in the patients who has cardiac pacemak pacemaker synthetic okay that's that's an important aspect to be noted so how this ept is going to respond to the different situations i mean basically you have a reversible pulpitis you have irreversible pulpitis or you have a hyperplastic pulpit right so how they respond to these three categories is an important aspect so in the reversible pulpit is the tooth responds to less amount of current than normal okay so it responds to the less current less current than the normal whereas in coming to the irreversible pulpit is it requires more current it requires more current to respond and when you take this hyperplastic pelvis when we are talking about the diseases of pulp i will be discussing in detail about the hyperplastic pulpit is what happens in hyperplastic pulpits is the number of nerves decreases in hyperplastic pulpits whereas the vascular supply will increase so that's the reason why as the number of nerves decreases there is less pain in hyperplastic pelvis and there is more bleeding so immediately whenever you touch it bleeds fast so there is more bleeding so whenever you have less number of pulp whenever you have less number of nerves in the pulp what happens uh the the the pulp polyp that is hyperplastic pulpit is will will contain less number of nerve supply than the normal pulp and also so because they contain less number of now they require more current more current to give a pain okay that's the sign that you have to make a note when you're talking about hyper plastic compartments reversible pulpit is less current irreversible pulpit is because those are damaged more current is required hyperplastic pulpit is they have less number of nose so more current is required to elicit the pain so uh okay next one is the location where you have to keep this tip is is an important aspect okay so you have to keep uh you have to keep this particular tape in the anatomical location where there is high density of nose so it will be different for anterior teeth and it will be differing for the posterior teeth for example if it is an anterior tip the anterior teeth which part of anterior teeth will have more nerves of place in sizzle one third so it's incisional whereas coming to the posteriority it's going to be the middle one third the middle one third is going to have the the more density of the nose okay so it is uh upper one third the posterior is the middle panther so other important aspect that you have to make a note is about the uh the defects in this test okay so in few cases you will get false positive false positive in few other cases you will get false negative so these are the problems with this so at which conditions you will have false positive and which conditions you will have false negative is again a most commonly asked question so what happens uh the false positive can be seen in the cases when you have a moist necrotic pulp so pulp is dead but it ha it is moist so moist is going to allow the current okay so the pulp is dead but you will have a positive result in this case or whenever you have a partial necrosis for example if it is a multi-rooted teeth you have you have a necrosis in two roots and the two roots the pulp is vital so this is going to give a false result so whenever you have a partial necrosis in a multi-rooted teeth it's going to give the result so whenever the electrode is going to contact the gingival tissue or whenever it's going to contact the wet surfaces it's going to give a positive result whenever uh the tooth is having an acute alveolar abscess it's going to give a positive positive result or whenever the patient is too anxious high potential or hyper hyper react to patients okay with the without touching the they give pain and telling that it's vital so such conditions comes under the false positive so what happens in the false negative if it is a calcified channel it's going to give false negative out of the patient is having high thrust hold level of pain it's give a positive result now the patient is having a painkiller before testing it gives a false result or recently erupted teeth with immature effects because the nervous system is not well developed it's going to give a false result okay or or ah or if if the if it is not working at all if it is not working at all it gives a false or recently traumatic death it's going to give a false word so they can ask you in which of the following conditions you have a positive false positive and so the following conditions you have a false negative is the most commonly asked question for you so just make a note of it so you can they can ask you this type of question type of pulp testing used in this case you can see this case is a full ground restoration so full crown registrations ah what is the pulp test that you have to use is carbon dioxide snow that is minus 78 degrees carbon dioxides know that you have to use when you are going for this particular type of test okay so before going into this i just want to add a note about your anaesthetic test so an aesthetic test is uh basically done by an intra-ligamentary and very few cases they can go for the mode of injection as an infiltration so basically the anesthetic test is useful uh first of all useful to identify the maxillarity and the mandibular teeth who charge it belongs and you have to do this test from the posterior tube to anterior teeth by which you're going to i you're going to like you're going to anaesthetize each and every teeth by by which you are going to rule out that particular teeth and you are going to come out with the ultimate teeth which has the issue that is the anesthetic lesson coming to the test cavity test cavity is going to you are going to prepare a cavity basing upon which you will tell the vitality of the tip so that is going to be the last option means you are destroying means it is and you're causing some trauma to the teeth so basically anesthetic cavity what you have to do is you have to drill the cavity in an un anesthetized teeth okay so test cavity is a cavity that is done okay drilling a teeth without a water coolant make a note the points to be added is without without water coolant because the heat has to cause the pain without a water coolant and without giving a layer you have to without giving a lay so this has to be done these two has to be done then the patient complaints of pain by which you can tell that the you have some sensitivity you have some sensitivity towards the particular thing okay the next comes is uh the zero radiography okay so what what happens like few important things of course these are very very i mean like essential things that you have to make you note when we are talking about your oral radiology but my concern is i want to cover uh these aspects uh in endo point of view okay so in endodontics point of view i feel like i need to cover the reliable stuff of this so what happens in zero radiography zero radiography is something called as an electrostatic imaging system that uses a uniform charged x-ray sensitive selenium alloy photoreceptor okay so this is an electrostatic so points to be added is this is an electro static imaging system this is an electrostatic imaging system in which the regularly used selenium coated photo receptor plate so what is the material selenium mostly selenium but in very few cases they can use aluminum also but mega knot selenium is an important point electrostatic imaging system is an important point and this procedure is very rapid it is a very rapid procedure uh which is done in 20 to 25 seconds time duration is very important 20 to 25 seconds and the most important point about this in examination point of view is ah it has a peculiar feature that is called as edge enhancement property so it has h enhancement property and it has it it also has a sharper contrast so these are the advantages that are associated and when you're talking about the exposure the uh the radiation levels or radiation exposure is also less clear so so the three important points that you have to make a note about this is is very rapid that is it it takes place in a duration of 20 to 25 seconds the second one is edge enhancement property it has a sharper contrast and the radiation exposure is very very less so coming to the desert one disadvantages that is associated with this uh is okay uh the disadvantages that are basically associated with this is it has a greater degree of artifacts so whenever you compare the whenever you compare to the you compare to the conventional radiographs you have more degree of artifacts here and whenever you have a larger areas of bone okay means more than two centimeters are shown better with conventional radiographs okay than than the zero radicals whenever you have a larger defects larger defects okay so this is this cannot be a good option for this okay so what are the advantages so the advantages are rapid procedure 20 to 25 seconds edge enhancement property sharp contrast decreasing the radiation exposure the disadvantages are high degree of artifacts and larger defects of bones cannot be clearly appreciated when you compare with a normal conventional radiograph so that is about the zero radiography that you have to make a note second one is rvg hope you are very familiar because most of your colleges now started using this okay so that is called as rpg that is nothing but radio visual graphics so i don't want to talk much about this okay so the main advantage is decreasing in the exposure so because we talked more about this in your overall radiology decreasing exposure and the main disadvantage of like when you compare the resolution okay so coming to the disadvantages the resolution is less so i mean the clarity of the image is less when you compare with the conventional radiograph and the second one is expensive and the third one is soft tissue images are not clear when compared with the conventional soft tissues are not clear when you compare with the conventional that is about rhythm the next comes is a digital subtraction subtraction radiography okay so this is subtraction radiography is going to be like the word clearly says subtraction means you're going to take two radiographs radiograph one radiograph two radiograph one radiograph two after a duration of time for example the the duration between these two radiographs and these two radiographs is some three months so and three months and you are going to compare the two radiographs by subtracting one from other by which you are going to know the prognosis of the teeth okay i hope you're very clear right so a a area of focus will be taken and the subtraction will be done and you will get to know what is better property like which like what are the changes so easily you can use this particular thing for the follow-up of a particular case so that is all about the digital subtraction radiography so what this basically i mean like the use of this is basically in most of the follow-up cases okay so the first the first image what you're going to take is going to be considered as a it's going to be considered as a baseline and followed by a duration of type you're going to take a follow-up radiograph this is called as in a follow-up follow-up radiograph and you're going to register register them and compare the differences between the two images that is you're going to you're going to see the difference between the radiographic density of the two images for example if the outcome in the outcome if you have a bright area bright you have a bright area ah then uh then that is called as the then that is called as the gain there is some deposition that has occurred if you have a dark area then there is then there is a loss loss of the density okay so so and make sure the the most important thing that you have to do is the projection geometry should be same because the same way the x-ray should be the landmarks and everything which were kept as a reference for the baseline radiograph and for the follow-up radiograph should be same so that the subtraction process can be so the main disadvantage of this technique is projection geometries are very difficult to follow and that can lead to some sort of error so that's all about the digital subtraction radiography so at this particular point we need to make a note about p a i scores or p a i index that is nothing but called as peri apical index so what happens in periapical index so in peripheral index you have one two three four five scorings i think in 2017 or 18 they have given what is periapical index three description so one is normal peripheral structures okay so this is normal a periapical structure and whereas two there is small change in the bony structure okay you have a small change in the surrounding bone whereas coming to the three there is change in the bony structure with mineral loss you can appreciate a very huge mineral loss okay and the fourth one is periodontitis with well defined radiations you will have periodontitis also with well defined regulations and the fifth one is severe periodontitis with i mean like more intensified futures so make a note about this pa index that is called as periapical index ah the next comes is the vitality test until now we learned about the sensibility tests okay sensible data sensible water sensibility test which helps in determining the nerve sensitivity vitality vitality means vitality is related to blood supply whereas sensibility is related to the nerve supply all your thermal tests that is heat test cold test or your epds or your test cavity or your anaesthetic test so all that is what you have learned until now the talks about the nerve supply to the pulp so now we are going to talk about the blood supply to the pulp that is called as vitality test the first one that you have to make a note about is laser dipolar flow matrix it's a non-invasive test because you are not going to cause any damage to the tooth structure which helps in measuring the blood flow okay it's going to helps in measuring the blood flow how when you are going to hit a light okay you're going to hit a light and this light a part of the intensity of this slide will be observed by the red blood cells that are present in the body which are moving and some sort of reflection will goes off and which is detected by the photo detector okay so the drift in the change the change in the light density or the wavelength which helps in determining the determining the blood flow so that is called as laser doppler flow material which is based upon duplet's principle okay what which we have learned in the 11th and 12th standard so for the echo echo so something like something is going to come hit the red blade red blood cells there will be some deviation and it's go the echo is going to go back so that is called is based upon the duplet's principle laser diplomatically the word clearly says that it determines the flow of the red blood cell the second important is pulse oximetry okay so pulse oximetry so they can ask you questions on pulse in now because most of you are using it came a regularly used thing right now so similarly your pulse oximetry is useful for also knowing the pulp vitality so pulse oximetry is also a non-invasive processor is also a non-invasive procedure which helps in knowing the oxygen metric with he previously it is flowmetric flow we are knowing the flow now it is going to helps in knowing the oxygen oxygen saturation levels of the blood which are present in the pulp so which oxygen means basing upon the concentration of hemoglobin its its going to help so here you can see two types of ah wavelengths are used okay okay clearly giving you a hint okay one is 660 second one is 940 right so what is 660 660 is red light diode so you have two diodes one is red light diode which is 660 nanometers 660 nanometers other one is infrared diode which is of 940 nanometers most commonly asked questions are these numbers 660 and your 940 okay so what happens here okay what happens here is ah so once it was asked in the aims and pga there basing upon which principle does this pulse oximetry is going to work so pulse oximetry is going to work on two principles then one is b its principle one is peach principles and second one is lambert's principle so what is beard's principle brain's principle is nothing but the absorption of a light is directly proportional to the concentration of the sample that is given so absorption is the that if the density or the concentration is very high the absorption of light will be more if it is less the absorption of light will be less so that is the beard's principle and the second one is lambdas lambert's principle the absorption is proportional to the thickness of the sample first one is concentration of the sample second one is the thickness of the sample so basing upon these two principles your pulse oximeter is going to work so the important points in the pulse oxymetry are it's a non-invasive procedure it helps in knowing the blood saturation levels it has two diets and their wavelengths are important and it works on two principles and what is the meaning of those two principles is a very very important in examination point of view the next comes these are few advanced things but there are chances that because nowadays i mean like advanced questions are regularly asked and most of your advanced questions will be from perio and like from endo perio cons and oral surgery preferably when compared to any other subjects because these are the clinically more more like more oriented subjects so they are asking questions on this so that is called as joule wavelength spectrophotometer so what is the dual wavelength okay the word clearly gives an idea that they have two wavelengths okay so they are dual wavelength spectrophotometer is is one of the uh principle is one of the way by which your pulp vitality can be known so the few few important things that you have to make you know when you're talking about this dual wavelength so this dual wavelength helps in determining the oxygenation of the blood oxygenation of the blood at two wavelengths one wavelength is 760 nanometers and the second wavelength is 850 nanometers you have two wavelengths one is 760 and second one is 850 nanometers and these particular uh like the the i mean the sensors the sensors they helps in knowing the oxygen oxygen levels of the blood at these two levels that is 850 nanometers and 760 nanometers and uh and this particular dual wavelength spectrophotometer was able to differentiate okay the productive values for a normal teeth and an abnormal teeth so you're going to compare a normal teeth to an abnormal teeth by which the variations can be gives an idea with other futures other features and the symptoms of the patient by which you can diagnosis the case so you can ask me like what is the difference between this particular thing or pulse oximeter okay so pulse oximeter the main difference between the pulse oximeter is the blood flow depends depends upon the pulse that is pulsation because the blood flow will increase whenever the pulse is more whereas this particular type of dual wavelength for spectrophotometer measures the oxygen changes in the capillary blood rather than the supplied blood okay so most your pulse oximeters depends upon the supplied blood okay whereas your your pulse oximeter pulse oximeter depends upon the supplied blood vessels blood vessels whereas your dual wavelength spectrophotometer it depends upon the capillary capillary prints so that is the main difference between those two types of devices which almost works in the same principle okay so so once we are done with this the next important aspect is uh tact that is tuned aperture computer tomography okay which is called as tact so the main important is when when you you're going for the stacked radiograph what happens is you're going to expose the same teeth in different directions and by using a software you're going to combine these all radiographs which gives a tuned aperture this is a tuned aperture different apertures and you're going to buy by by by by using a software you're going to combine all this in a simple simple so they're gonna ask you question is how many radiographs are taken in the stacked eight radiographs are taken on the stack you can see one two three four five six seven eight so eight different angulations you're going to take a radiograph and all these are going to be combined to form a single radiograph by using a software which has most of your questions will number of radiographs number of angulations of images taken in tuned aperture tomography is eight so i mean like i i mean like compared to many other scenarios like if you go uh in detail so i mean even ct is used in some cases but the most prone or most commonly used nowadays is the cbct okay cbc2 of course we learn in detail about the cbct uh in your oral radiology part okay cbct okay cone beam computer tomography is the best way of identifying any radiograph related stuff so they're going to ask you like among the options which is the best one to determine the number of canals on the radiograph or or or an epical root fracture at which level or anything the best way is because this you can see this in a different layers of cross section in the both horizontal or vertical at any level by which you can clearly identify any sort of abnormality or problem with with this so that is the main advantage because you will have a different oxels in this and you can observe at each level like which like which level it has started you can clearly determine so this is the best thing right now available for an endodontist to know the outcome of the treatment and to it also helps in knowing the prognosis or anything like diagnosis and anything so the best thing right now uh to know the anatomy at the best is cbct for an endodontist so of course we'll learn in detail about this when i'm talking about the indoor related stuff yeah done for now signing off dr street