 Welcome back to another session in dentistry and more today we have the last session of dental anatomy that is mantibular second premolar except maxillary and mantibular third molar all teeth were explained in videos can check the playlist so we'll start with mantibular second premolar the numbering system universal system you have 20 and 28 this is mantibular left second premolar and this is mantibular right second premolar next we have our Zygmonte Parma system Zygmonte Parma system we have 5 and 5 and the FTA system we have I'm sorry just 3 5 and 4 5 and well coming to the chronology who have the first evidence of calcification by 2 to 2 and half years and enamel completion by 6 to 7 years then we have eruption by 11 to 12 years and root completion by 13 to 15 years now we'll go back to our aspects that is buckle to occlusion aspect the first thing is the buckle aspect again it is a tropic soil in shape the cervical side is short and occlusion side is long the outline mesial outline is likely concave till the mesial contact area and the same with the distal contact area and the distal the mesial slope is shorter than the distal slope or may be equal and this buckle cusp tip is mesial to midline this is almost like mantibular first premolar okay of similarly the cervical ridge and buckle ridge two developmental grooves mesial and distal to the buckle ridge and the root is contrived with rare distal inclination of the apical third well coming to the lingual aspect similar to the buckle aspect but in a reverse manner there may be one or two lingual cusp compared to the first premolar these lingual cusps that is shorter than the buckle cusp and in case of tree cusp type the mesial lingual cusp is a larger one than the distal lingual and very little lingual convergence and the two lingual cusp separated by a lingual developmental groove and cervical line which is slightly convex or even straighter whereas the mesial outline the rhombus shape is there due to the lingual inclination and similar to the first premolar but differs in wider buckle lingual size and the buckle cusp is just buckle to the root apex the lingual cusp are well developed the mesial margin which is straight and perpendicular to the long axis and there's no mesiolingual developmental groove so in mantibular first premolar i was saying there was a mesiolingual developmental groove which is very very unique and you can easily identify the mantibular first and second premolar with using that identifying feature that is the mesiolingual groove on the root but in second premolar there is no such groove the root is longer than and with a bland apex the maximum convexity of the lingual outline is located at occlusal third whereas the distal aspect it is similar to the mesial surface but differs in the distal margin rich which is present more surveyically and the tips of both lingual cusps can be seen from distal side and in two cusp type there is a mesiolingual cusp is there the distal lingual developmental depression can be seen whereas the occlusal aspect if it is a three cusp type the geometric outline is more of a square and it has one buckle cusp and two lingual cusps so the arrangement of cusp according to the size the buckle the mesiolingual then the distal lingual okay buckle mesiolingual then the distal lingual every cusp has a triangular ridge and y-shaped developmental groove separating these three cusp and there is a central foza present central pit present and mesial and triangular foza is there mesial and distal triangular foza is there and also mesial and distal marginal ridge so we were talking about the three cusp type but the two cusp type the geometrical outline is more of round and there is lingual convergence there is one buckle and one lingual cusp there may be a transverse ridge which connects the buckle and lingual cusp and the central developmental groove or maybe a h or u-shaped and the surface has many supplemental grooves and mesial distal foza are more like rounded okay so this mandibular second premolar the occlusal anatomy has more feature because some times the lingual side has two cusp in those cases it will be more like a square otherwise it will be a round one okay so that was all about mandibular second premolar so we are winding up the dental anatomy sessions with regard to the tooth anatomy from maxillary central incisor we finished maxillary second molar and mandibular central incisor to maxillary molars so all teeth videos are uploaded in the playlist you can check the playlist in the channel under dental anatomy so dental anatomy is all about understanding or studying the teeth so you need to study under five aspect buckle lingual mesial distal and occlusal and a little bit about the root anatomy and the tooth numbering system chronology and dimensions okay and with neat diagrams you need to write the answers so i'll come up with another topic in dentistry and more thank you