 Hello everyone, welcome back to another session of Dentistry and more. We are continuing our dental anatomy sessions Today we have Mantibula second model last session we finished Mantibula first molar Mantibula first molar is a tooth with how many features in each aspect? Let it be buckle lingual, measly, distal and occlusional aspect has so many features many forza's pits and many Grooves Coming to Mantibula second molar Many features are not very prominent So mostly the maxillary first molar and mantibula second. I mean mantibula first molars will be having most of the features So, we'll start with our numbering system We have three numbering system as you all know universal Zygmon T Parma system And FTI system So universal system since it is Lower teeth We have one here 8 9 16 17 And this will be 32 Okay, so We have two second molars that is Left second molar it will be 18 and Right lower second molar 31 So when you're studying universal system, always you need to have one eight nine 16 17 24 25 and 32 in your mind After that you connect the particular tooth. Okay, so if 31 means it's a second molar. So you need to have 32 in your mind that is a third molar right third molar So the next tooth 31 will be the right lower second molar You can't buy hard all these only thing You can make sure that you know one eight nine 16 17 24 25 and 32 are the end tooth in each quadrant The Zygmon T Parma system it will be seven and seven and FTA system will be three seven And four seven. Okay, so that is about Our Systems of numbering Next we have the dimensions and chronology In chronology, we have first evidence of calcification between two to three and a half years enamel completed Between seven to eight years eruption by 11 to 13 years And root completion by 14 to 15 years Now we have Dimensions So dimension well coming to the dimension second molar overall length is 18.8 mm That is overall Then the crown length is very shorter 5.5 mm length of root is 11.3 mm Then her mesiodistral diameter Is nine point nine mm And the same at cervix is seven point two mm And labiolingual dimension is eight point seven and Six point four. Okay Now let's move on to the various aspects So we'll start with each aspect Before that the principle identifying features of mandibular second molar It is more like a rounded Square occlusal outline. Okay with four cusps two buckle two lingual There is no distal cusp. It is not as wide mesiodistrally as to the Mantibular first molar because it's a square shaped And buckle aspect has just one groove whereas in first molar it has two grooves And there is lots of supplementary groove on the occlusal surface And the two roots which are less broader And they are more close together compared to the Mantibular first molar. So these features will make you to Easily identifying the mandibular first and second molar in your exam That is a practical exam. So we'll start with our buckle side or buckle aspect So the picture you can easily make out the crown is shorter and narrower Mesiodistrally than the first molar Then there is one developmental groove which divides the Mesio buckle and distro buckle cusp which are almost equal in size. Okay, you can see the size In first molar we have a larger mesiolingual than the Mesio buckle than finally the distal but this is mesio buckle and distro buckle are almost same And there are two roots hermesia and distal and are less broader and they're more close together Next we have our lingual aspect Only the lingual cusp is in view because the tips of the lingual cusps are higher than the buckle cusp Okay And the mesiol aspect Well coming to mesiol aspect the cervical ridge Buckley is less pronounced and occlusal surface is constricted bucklingually And the cervical line shows no curvature. It is almost Flat And the two roots may be seen from this side Whereas the distal aspect The absence of distal cusp and distro buckle groove compared to the mandibular first molar And most of the occlusal surfaces can be seen from distal aspect just like any other tooth And now we have the occlusal aspect Occlusal aspect it is roughly a rectangular the central groove is in the center With the lingual and buckle developmental grooves meeting with the central groove at right ankle Like this This is 90 degree And there are focus Two buckle that is mesiobuckle and distro buckle and two lingual that is mesiolingual and distalingual And many supplemental grooves radiating from the elemental grooves So that was all about mandibular second molar as I said less features compared to the mandibular first molar Mostly the first molars will be Asked for your university papers Sometimes their last second molar sometimes it will be comparison of mandibular First and second molar so whenever you are studying mandibular first molar just Go to the mandibular second molar And compare and study it will be very much easier than mandibular third molar is not very important on a Exam point of view. Okay, so I'll come up with another topic in dentistry and more. Thank you