What is the Difference Between Maxillary and Mandibular Molars?

The main difference between maxillary and mandibular molars lies in their location, structure, and characteristics. Here are the key differences:

1. Location: Maxillary molars are located in the upper jaw, while mandibular molars are situated in the lower jaw.
2. Buccal Grooves: Maxillary molars have one buccal groove, while mandibular molars have two buccal grooves on the first molar and a single buccal groove on the second and third molars.
3. Buccal Cusps: Maxillary molars have two buccal cusps, while mandibular molars have two or three buccal cusps.
4. Roots: Maxillary molars usually have three roots: mesiobuccal, distobuccal, and lingual. Mandibular molars have only two roots: mesial and distal.
5. Cusps: Both mandibular first and second molars have four cusps of similar size (two buccal and two lingual), while most maxillary first and second molars also have four larger cusps (two buccal and two lingual), but the distolingual cusp varies in size and is often considerably smaller, especially on maxillary second molars.
6. Crown and Root Ratio: The crowns and cusps of maxillary molars are centered over their roots, while the root trunk on mandibular molars is shorter than on maxillary molars, and their crowns may appear to tip distally relative to the midroot axis.

In summary, maxillary and mandibular molars differ in their location, the number of buccal grooves and cusps, root structure, and crown and root ratio. These differences can be used to differentiate between the two types of molars when analyzing dental images or casts.

Comparative Table: Maxillary vs Mandibular Molars

The main differences between maxillary and mandibular molars can be highlighted through their characteristics, as shown in the table below:

Maxillary molars are located in the upper jaw, while mandibular molars are placed in the lower jaw. Maxillary molars have two buccal cusps, one buccal groove, and three roots, with two on the buccal side and one on the lingual (palatal) side. Mandibular molars, on the other hand, have two or three buccal cusps, two buccal grooves on most first molars, and two roots, with one mesial and one distal root. The root trunk on mandibular molars is shorter compared to maxillary molars, and the cusp of Carabelli is present in maxillary molars but absent in mandibular molars.