okay everyone so in this video what we're going to do is we're going to look at arteries and we're going to focus on the arteries we see in the head and neck now when we um look at arteries what i want you guys to remember is arteries start with an a so think of a like a weight so the function of arteries to what arteries do is they take blood away from the heart and then there are veins which is um in blue it's not shown here but veins take blood back to the heart so arteries are taking blood away from the heart and the reason why i have this picture over here is that there is something called the right common carotid artery and that one is right here right here so right common carotid artery and what's interesting about this is this takes all the blood up to the area that we're interested in so we have a right common carotid artery we also have a left common carotid artery and that takes it to the left side now when you look at the carotid artery there is something called an external carotid artery and then there's an internal carotid artery so think about the smaller one actually here is the external one and it's external because it's you know further out okay so anything that's further out is external anything that's more deep in the body is internal so this is an external carotid artery and think about which one applies to the dental professional profession a lot more would it be the internal artery which goes up into the brain or do you think it could be the external carotid artery which um goes to and you can see right you can see where it's going it's going to the mandible or the lingual is going to the facial and it's also going to the maxillary artery so we are more interested in the external carotid artery so again here's the common carotid artery and then it does branch off to external and internal and um we're going to look at all these different types of arteries so facial artery something we're going to be interested in lingual artery which supplies the tongue is another one we will look at so internal carotid artery external carotid artery so this is the common carotid artery and then it branches off to internal and external and you can see here is the lingual artery and think about where you think the blood supply is going so it's going to the dorsal the dorsal means the top of the tongue and it's also going to the sublingual artery so it's not going to the floor of the mouth and if you look at this slide here lingual artery where does the blood go if the blood vees are supplies the tongue so it goes to the tongue and also the floor of the mouth as well so the lingual artery is you can see here in this picture is actually very clear that you can see all the blood vessels or arteries rather are just going and feeding the tongue and also the floor of the mouth when you look at the facial artery okay so again we have the common carotid artery here is the internal carotid artery here is the external carotid artery we looked at the lingual which means the very bottom the tongue then we're going to now look at the facial and the facial starch right here and look at the facial it's basically covering almost the entire face so it's supplying almost the entire face up until the very edge of the eye so the facial artery ends at the inner corner of the eye and what it does is it supplies blood to all the skins and muscles of the facial expression but the maxillary artery this is the biggest type of artery because there are 15 branches so the facial artery supplies all the muscles of facial expressions remember we looked at like how when we squint when we open our mouth those muscles that are innervated they're innervated by the facial artery but the maxillary artery this is like the biggest artery because there's 15 branches and i'll show you a picture in a bit and what the maxillary artery does is it supplies you know muscles of mastications or muscles for chewing it gives muscle a sorry it gives blood to the teeth supplies blood to the teeth um supplies blood to uh the the nose as well and the maxillary artery is a very important one because when we do local anesthetic when we're trying to freeze some teeth we have to to um reach out to one of the branches within the maxillary artery to freeze it and that will make more sense as we look at the different axillary arteries so maxillary arteries the one that i want to look at right now is actually okay let's actually start with this picture so local anesthetic is a very important component to learn about in the board exam and this is all the different blocks that are out there and when i say blocks blocks are different types of local anesthetic injections that are done to numb specific areas within the mouth so if we look at this one infra orbital block infra orbital is if i show you a picture i don't have a picture here uh the one that highlights infraorbital but this over here this form foramen is called the infraorbital foramen so if i were to inject my needle the local anesthetic needle somewhere here the infra orbital foramen remember this opening has a lot of blood vessels and when this blood vessels get hit with the local anesthetic solution then all of this will be numb so the upper lip and the anterior teeth and even like the lower eyelid the asa msa and psa so asa msa and psa this is all again part of the maxillary artery so all of these are coming from the maxillary artery so if i look at the maxillary artery which is a little hard to see here but here's the maxillary artery you can see like how many branches they have is actually 15 different branches so one of them one of the branch is an anterior superior alveolar artery and so let me show you that maxillary artery anterior superior alveolar artery so if i were to numb the anterior teeth what i could do is i couldn't um just numb these three teeth and to do so i would have to put these arteries to sleep if i wanted to numb the middle superior alveolar or the middle teeth so the premolars i would have to numb or somehow get my local anesthetic in these arteries which is the middle superior alveolar artery and if i wanted to numb the posterior teeth then i would have to make sure that i somehow hit the posterior superior i'll be older or do we so here this is the maxillary artery and look at all those branches that it stems off so it's hitting a lot of different branches it's feeding a lot of different things within the maxillary um within the head and neck anatomy so even the palettes if i wanted to numb the palette the greater palatine artery could be hit and it would numb the hard palate the lesser palatine artery that one supplies the soft palate which is further back so here again posterior superior alveolar artery so posterior superior alveolar artery hits all the posterior teeth middle superior alveolar artery hits the middle so premolars and possibly even the six and then the anterior superior alveolar artery is reaching the anterior teeth so if i want to numb just the anterior teeth this nerve has to be affected if i wanted to numb the premolar teeth this nerve has to be affected and if i wanted to know or to numb the very back teeth the posterior teeth then the posterior superior alveolar artery has to be hit and if you think about anteriors it makes sense right anterior superior alveolar artery means anterior teeth middle refers to the middle teeth so the premolar and posterior refers to the back molars so here again we see the infraorbital artery and when i um if i were to numb the infraorbital artery it would um numb the anterior teeth so infraorbital artery hits the anterior teeth the upper lip and even the lower eyelid and sometimes even the side of the nose i've had this done before and it felt it feels really funny we also have um veins and actually sorry before this slide i want to show you this one so this is a great slide because it tells you all the arteries that supply the different areas in the mouth so if you wanted to numb the mandibular teeth the bottom teeth the nerve that you need to hit is the inferior alveolar nerve again that's stem from the maxillary artery if you wanted to numb the maxillary molars you need to do a unit to block the posterior superior alveolar artery which again stems from the maxillary arteries and it goes through the back teeth the upper teeth if you wanted to numb the tongue for some reason then you would have to aim at the lingual artery um let's see here soft palate there's a lesser palatine artery that can you know uh that supplies the soft palate floor of the mouth the lingual artery supplies the floor of the mouth so it's really interesting i like how the slide has broken it down we also have veins so just like arteries take blood away from the heart veins bring blood back to the heart and so veins are in blue and what i want you to draw your attention to is this um place over here and this is the pterygoid plexus of veins that's what it's called where it's like a mesh of veins like just intertwined here and the reason why i want to bring this into your attention is sometimes when we're doing a local anaesthetic what can happen is if we if we nick this area over here then we can get something called a hematoma which is a swelling and discoloration so if you pierce a vein um you know maybe you have an improper angle especially when you're doing a posterior superior alveolar nerve block which is a nerve block which is further back blood will escape and when blood escapes you can get a hematoma it's not necessarily harmful um it's just a swelling it does go away you know over time but it is it may look alarming and so the client may you know not like it but the reason why this happens is because you pierced a vein so let's look at a question a possible test question all of the following are branches of the facial artery except one which one is the exception so this is the facial artery and you can see it goes all the way to the inner corner of the eye it's going um you know to them oh so maxilla is going to the mandible as well so what is not part of the facial artery if you said lingual you would be correct because lingual artery is a complete separate arteries a facial artery is a different artery and a lingual artery is a different one so all these ascending palatine artery inferior labial artery and submental artery they actually are all branches of the facial artery but the lingual artery is not a branch of the facial artery it has its own branch so therefore the answer is lingual artery let's look at another question the posterior superior alveolar artery supplies blood to give you a few seconds so if you said maxillary posterior teeth and periodontium and maxillary sinus you would be correct because it only goes to the posterior teeth the anterior teeth is for the anterior superior alveolar artery the heart and soft palate that's um the greater palatine and lesser palatine arteries and the mandibular teeth and floor of the mouth well that is the inferior alveolar artery which comes into the enters into the magic lip foramen so the one that is this one is the posterior superior alveolar artery and you can see right here it is hitting the back teeth maxillary posterior teeth the top back teeth let's look at salivary glands so salivary glands there are three major ones that you should know there is the periodic line which is a really big one there is the submandibular gland which is just under the mandible and then there's the sublingual which is just under your tongue okay and all of these um glands they make saliva and then saliva has to come out somehow and enter your mouth so it has to go through a duct and so what i want you guys to know is that the parotid salivary gland has a duct where it releases its saliva and that duct could be called a perotic duct it could also be called a stenson duct so think of past pa for parotid st for stenson so that's how you can link them both together this is all from student rdh by the way we have the submandibular gland so the submandibular gland is right under the mandible sub for underneath okay so it's near the mandible and then it has a submandibular duct or it has a wharton stuck and again how can you remember this well the m in submandibular flip it and you get a w the w is for fortunes lastly we have the sublingual duct which is just underneath the tongue and um it does have many different ducts that come out and you know releases saliva into their mouth and the ducks are called either sublingual ducts or the bartholin duct so sub has the word be be for bartholin also you can think of subway think of like the subway where you go for lunch and imagine that subway having a bar which is kind of unique for a subway to have a bar but then that's how you can remember sublingual gland has bartholin duct now this is interesting even though the periodic line is so big it only releases or makes 25 percent of saliva the maturity of the saliva is made in the submandibular gland which is like 60 65 of saliva and then the sublingual gland which is tiny makes 10 of um saliva and we know that saliva is really really important because it helps us um it makes it easier for us to swallow food it helps break down the food it helps us with swallowing food it helps us with our speech as well and it prevents our mouth from drying out because we know if our mouth dries out we're not at risk for bad breath we're now at whisper cavities as well okay so periodic lens it's the largest salivary glands but it only produces 25 of the saliva remember passed um for stenson stuck because it's right near and it actually opens right into the where the maxillary second molar is so sometimes when you look inside to someone's mouth and you see that little flop of tissue and that bump that bump or flap of tissue is actually the parotid duct i've had many students looking at looking and they come and ask me like what is that why does that look so different during unique and it's actually the parotid duct that you're looking at submandibular duct is right here right at the floor of the mouth you can actually see it and this by the way is called the sublingual car uncle sublingual car uncle and sometimes the sublingual car uncle you could get a salary stone there and it's obstructing the flow the saliva can come out because of that salivary stone so there is treatment that could be done to get rid of that stone so this is like a before and after and then the sublingual gland you can see there's so many different ducts that come out and if i show you what it looks like this is a sublingual fold and that's kind of where the sublingual glands are too the sublingual ducts are also get released somewhere around here the saliva from the sublingual ducts can get come out over here so question for you the parotid salivary glands empty through the what duct if you said stenson ducts you are correct because remember past p-a-s-t stenson ducts is the name of the parotid gland duct let's look at the lymphatic system now so the lymphatic system is really unique because what it does is it tries to kill toxins so the lymphatic system basically it removes any fluids that leak out of your blood vessels those are called lymph those are called like basically any fluid or plasma that leaks out of the blood vessels it goes through the lymphatic system and it just kind of circulates in there and it removes it stops at a node like all these dots are lymph nodes and it stops at a nodes and what the lymph nodes do is it do is that they it's kind of like a checkpoint they'll um make sure if there's anything bad they'll try to you know take it out so it goes through many different checkpoints if you will um the the lymph the fluid kind of goes through all the different checkpoints and it just weeds out all the bad toxins and stuff so the lymphatic system is actually intertwined so circulatory system and lymphatic system work together and so this is your heart and remember the arteries take the blood away from the heart and the veins put it back in and so as the artery is taking blood away from the heart um when it goes to the capillaries there are lymph that comes out and these limbs they come out here and the lymph node checks to make sure if they're bad they'll they'll kind of like filter it out and if it's um and then it goes to another checkpoint and again if they see anything bad it'll filter it out and then it goes back into the veins and circulates within the heart so it's intertwined within the circulatory and the lymphatic system is intertwined within the circulatory system so we have lymph nodes which are those blobs that you see and they filter they filter the fluid so anything bad i'll take it out so in the head and neck we have many different lymph nodes so we have the occipital lymph nodes which is just um if you think of the occipital bone that we have at the back it's behind the ear it's at the bottom of the um head and again imagine there being lymphatic vessels all around and then when they when the fluid goes into these nodes and then they filter out the bad stuff they then go to another node and eventually what it does it goes um all the way down into the deeper notes so it drains into the deeper nose we have the mastoid nose also known as the post auricular nodes and this is behind the ear and again all the fluid just goes all the way down to the back of the scalp so any excess fluid just goes down back to the scalp and it gets circulated within the body we have the pre-auricular and remember pre means in front auricular means ears a pre-auricular um carotid node and what it does is it drains from the anterior head above the eyes so anything above the eyes all the fluid will it will collect over here and it'll drain everything we have the submandibular node which is so this is the mandible it's just underneath the mandible and um it's below and behind the chin okay so it is right behind the chin and what does it mean well anything from the gums the teeth and the tongue they all go here and they get drained out over here so the fluid from the blood vessel that comes out gets filtered in these nodes and then they go down then we have the submental and submental this is the think of the mental foramen we have in um in the skull we have a mental foramen which is the opening right near the chin mental for chin and they drain the inside of the chin they build your chin also the floor of the mouth so underneath the tongue the tip of the tongue and the lower incisors they all go into the submental node and get drained out so here is a picture or actually a table which is interesting because it summarizes it very nicely so your gums where do they get drained the gingiva gets drained so there comes think about where your gums are against it gets drained in the submandibular or even the submental because gums are everywhere over here um and then it even gets drained into the deep upper deep cervical nose so all the fluid uh lymph kind of goes here and then it gets goes down and circulates in the rest of the body the palates are the palette it's at the roof of the mouth and think about what's close to the palette um so actually with the palette it goes straight into the um drains into the upper deep cervical nose so the upper part the teeth so this teeth over here and the teeth get drained into the submandibular and even the deep cervical note so the teeth kind of if they have any uh you know fluid that comes out in the blood vessels it gets into the sub mandibular or upward and actually deep cervical lymph nodes and then it goes into the body anterior part of floor of the motor the front part to the front of the floor of the mouth goes into the submental the submental is going to close by and then also the upper deep cervical nodes and the at the very back goes and drains into the submandibular because that's closest to it and you can see everywhere it's the deep cervical right so if not least of mandible then it eventually goes to the deep cervical nodes and it gets flushed out so here we can see it better so submental is just underneath the chin oh this was the mental foramen i was talking about so supplemental is right here this is submandibular node i have a better picture here submandibular nodes and we have the upper deep cervical nodes so somewhere here and then we also have the inferior deep cervical nodes so let's say this was a question you got on your board exam cheering an extra oral examination of a patient the dental hygienist notes okay so this word is lymphatic i'm struggling to lymphadenopathy and this basically means abnormal swelling of the lymph nodes and so if you see this abnormal swelling of the lymph just beneath the chin near the midline which lymph nodes do you think is involved retroauricular node inferior deep cervical nodes submandibular nodes or submental she said submental you are correct submental is the one that's just underneath the chin and if i show you the picture again so we can review let me um pull it up here is the submental so it's just underneath the chin the submandibular is further posterior further back the submental is just underneath the chin so the answer to this question is submental okay let's talk about root morphology now now before we get into um a deep root discussion let's just look at the difference between an anatomic root versus a clinical route so let's look at this picture over here anatomic root is the act is actually the the part of the the actual root basically the part that is fully covered by cementum and it's the part that's inside the bone but if you look at clinical root do you see how it's higher like that the clinical route see the atomic root actually starts right here where the root actually starts but the clinical route this is the part of the the area that we cannot see so the part that we cannot see is known as the clinical route the part that we can see is known as um so for example the crown the part that we can see is kind of a crown but the actual crown including the part that you cannot see so the gums are covering some of the crown at the bottom that whole section is anatomical crown but clinical crime is what you can see clinically so clinically this is the clinical crown and then clinically because we can't see this we're seeing that this is the clinical route but anatomical is more accurate because that's um telling you exactly where the root starts and ends the root trunk is the distance from the cej to the entrance of the location so if i were to color the root trunk over here let me try to attempt to do that this is the root trunk right here in fact i have a better picture in a different slide so maybe i'll bring that up later this area right here where the location is so this area that i am trying to draw is known as the interfercal or intra-radicular area it's basically whenever you have a two rooted or even a three rooted tooth the area between the roots is known as interfocal or intra-radicular so actually listen to this question what term is used specifically for the bone between the roots of a molar so if i were to draw age 2 this part over here what is this called and if you said intra-radicular you are correct interceptor so actually inter means in between and radicular is um between the roots interceptor interceptor refers to the bone between the teeth so if i had like another tooth over here the bone that's over here okay so the bone that's over here is known as your interceptor bone um so interradicular is right here interceptor is the bone that is that there's going over here there's bone over here so the bone between teeth is interceptor cega so cement or enamel junction is also known as a cervical line so if i were to draw the cej this part over here is my cej i think of it junction is where two areas meet so this is where this dimension because the the root is covered in cementum and enamel is right here which is on top of the crown so this is where the cementum and enamel meet hence why it's called the cej also known as the cervical line now the cega or it's actually the cementum is not smooth the enamel is nice and smooth but when you feel the cementum when you feel the root it's not as smooth so the cej has the most proximal incisal or occlusal curvature so where is it more curved on which teeth incisors canines premolars and molars or molars the answer is actually a incisors so let's look at it if you were to take an explorer and feel the bump over here the cej bump here it's more pronounced on the anterior teeth compared to the posterior teeth and the posteriority is actually more flat but in the anterior teeth it's a lot more pronounced so if you were in clinic and you know how sometimes you have to feel for the ceja when you're measuring the gingival margin line you really you you probably would be able to feel it more in the anterior anteriority as opposed to the posterior teeth okay so here's the picture of the root trunk is from the cej to the vacation the apex is at the very tip perry apex is whatever is around that apex peri means around so the area around the apex the area around the very tip of the root let's see what else we should know so as we said the cej has a rough toothed texture um and on the molars the cej is a lot more straighter so you can't feel it as much but but on the anterior and premolar teeth it does have that bump so you are able to feel it a lot more and sometimes when you're feeling for the ceg and you get that dip sometimes you take your explorer and it just dips in that dip is known as your cervical enamel projection or cep and um that is present on the molders the picture is the location on molars so let's look at root shape so we have to know which teeth have one root and which teeth have two or three roots so i'm going to show you the dentition when you look at the dentition when you look at the roots i want you guys to note that um in the maxillary when you look at the first molar second molar and third molar you can see it has three roots whereas when you look at the mandible or the mandibular teeth it has two roots and how can you remember that well think about um if you're hanging something from the ceiling like let's say you're handing a chandelier you need more anchors right you need more anchors for it to stay up there so that's how you can remember that maxillary need we need more anchors because of gravity right it can fall down so the more anchors so that's why they have three roots the more anchors the better the more roots the better it stays up there another unique thing that you should know is that when you look at the second premolar it has one root in the maxillary second premolar on the mandible have has one root but when you look at the first premolars you see how it has two roots in the first premolar and the maxillary and one root in the mandible two so i'll show you guys a trick of how you can remember that so the same thing applies for both ends okay so we know that all the anterior teeth and the maxillary second and mandibular premolars have one root but the maxillary first premolar has two roots okay so maxillary first premolar has two roots and how can you remember this well this is i'm something again from student rdh so maxillary first premolar if you um take out the m a you get x one p and if you get rid of the one and make it into an i you can get zip which sounds like sip so when you think of sip think of you sipping chew root beers okay so do you see how this kind of came about it's kind it's really unique when you think of it so max you get the x from max okay so x for max and actually you know it's the top first premolar you combine this you get x one p take the one the one and turn it into an i you get zip or sip and sip think of yourself sipping two root beers so now you know two roots in the maxillary first premolar the maxillary molars have three roots because it needs more anchors mandibular molars have two roots so let's look at a question that you could possibly get which of the following teeth is most likely to have a facial and lingual root so facial and lingual root maxillary lateral incisor mandibular canine maxillary first premolar or mandibular first molar so maxillary lateral incisor that only has one root plus this only has one root mandibular canine so mandibular canine again only has one root maxillary first premolar well maximum first premolar as we remember that trick that we just looked at zip has two roots okay so this has two roots and mandibular first molar has two roots as well so we know it is not a and b because they are single rooted now what we have to do is figure out which one has facial and lingual root if you look at the mandibular first molar it's not facial lingual right if you look at the roots the two roots one is on the mesial one is on the distal but if you look at the maxillary first premolar and there is one on the facial and there's one on the lingual so maxillary first premolar would be your answer because that's facial lingual you see how one root is on the facial one root is on the disc on the lingual so you should really know where the roots are located because that might help when you have questions like this so this is c because it has a facial and lingual root what about this one the root rank on which aspect of the maxillary for smaller is the longest where is there which root on the maxillary first smaller is the longest so the answer is actually this one is really hard to tell but the root trunk is the area from the cej to like the furcation and the distance from here to here is actually longer than any other distance around so that's why they're saying it's a distal and i know that's really hard to see i'm trying to see it's actually hard to see over here but it is the distal here's something else that's um unique to know so it's unique because vacations on mandibular second and third molars are slightly more apical than on first molar so what does that mean vacations on mandibular second and third molars are slightly more apical than on for smaller see this is the first one do you see the frication right here it is quite up high when you go to the second molar the frication goes a little lower so it's downwards and when you go here it's even more lower so it's more apical so it's kind of sloping right it starts high then it goes a little lower and the friction goes even more lower so that's a unique fact that the vacations goes more apical as you progress down root concavity so this is this depression that you see over here very very common in their maxillary first premolars this is the area that we find a lot of burnished calculus burnished calculus means when calculus that you just remove the outer layer but the inner layer of calculus is still left behind and that's really hard to remove and sometimes it's even hard to feel because it might even feel smooth so this table over here it actually tells you where do you have concavities and you can see maxillary first premolar yes there's a deep concavity that concavity that deep depression that we see it's really hard to remove calculus there so it's a common area for burnished calculus you can also see it on the distal of the maxillary first molars there's again a common area for burnished calculus so this is a great table i got from darby and walsh and it outlines the concavities that we have in each of our teeth and you can see some have no concavities like the maxillary centrals don't have any concavities whereas the maxillary first premolar that has a deep mesial concavity here are some of fused roots so sometimes roots get fused and the reason why they get fused and they're not separate is because during development it was really squished down there there was questions so they they had to fuse and they formed one large tooth instead of like two different routes and conquestance is when you have two teeth that are joined together by cementing the last one's congression so c for uh conquest and c for cementum so the refuse spike um cementing sometimes you can get accessory roots and so the maxillary first premolar we know they have two roots but sometimes they could even have three roots where there's two on the buccal side a facial side and one on the lingual side on the palate or gingival side of a maxillary incisor sometimes you can see these grooves these are known as a palatal lingual or sorry palette or gingival groups and this is um a great place for calculus to get formed or get um you know it gets formed in here or developed here and so now you think what's the best way to remove it because remember you won't be able to use a um a regular uh curette to remove it so maybe you want to use the toe end of a micro or mini or even extended shank curette so what the what am i saying what are these things what is a micro mini or extended shank you're at when you have tiny locations or when you have locations that you need to get into this is your standard greasy and you can see it has like a you know a shank that is regular inside but sometimes it is size but if sometimes if you want to get in deeper you can get an after five curette after five or after five millimeters so your typical uh curette may just get up to four millimeters deep or maybe even five millimeters but if you want to get more than five millimeters deep you need an after five and so an option five has a longer shank so it's able to get in there more deeper there's also a mini curette and a mini curette is if you look at this the tip part over here you can see that it is half that size so it's a very small tip and so these are great to get into the palatal lingual group so you can use the toe of that to get rid of it to get into the area because it's so short so mini is like this and micro is even half of that like it's even smaller so that you might be even better in to get into a very tiny place and it still has a long shank this is an and uh enamel pearl and sometimes a normal pearl gets confused with calculus because it feels like calculus so if it especially if it's not visible on the radiographs we sometimes are like is this a calculus or is this a normal pearl and dilation this is when they have a sharp bend in the root and this is because the the root was displaced when the teeth were forming okay well that's all for this chapter