Key Difference – Maxillary vs Mandibular Molars
Let us first see the meaning of the two terms, maxillary, and mandibular, before looking at the difference between them. Maxillary molars are the molars in the upper jaw while mandibular molars are the molars in the lower jaw. In an adult, there are four types of teeth found in both maxilla and mandible, namely; incisors (8), canine (4), premolars (8), and molars (12). In this article, we mainly focus on the difference between maxillary and mandibular molars. There are 6 molars in each arch, and three molars on either side of the arch. The crown of the molars has modified into an occlusal (chewing) surface with 3 to 5 cusps. Moreover, the occlusal surfaces of molars are larger than that of other teeth. The main roles of molars include the mastication of food, maintenance of vertical dimension of the face, and help to keep other teeth in proper alignment. The key difference between them can be observed in their position and the structure.
What are Maxillary Molars?
Maxillary molars are the 6 molars on maxillary arch. In lingual view, geometric form of these molars is a trapezoid. In occlusal view, these teeth are rhomboid with 2 acute and 2 obtuse angles. They have two buccal cups and one buccal groove. The buccal surface is relatively verticle. Maxillary molars have 3 roots with tripod arrangement, which enhance the anchorage in alveolar bone. The presence of oblique ridge on the occlusal surface is a characteristic feature of the maxillary molar. The crown of the maxillary molar is more centered over the root.
What are Mandibular Molars?
Mandibular molars are the 6 molars found on mandibular arch. They have 2 roots and have no oblique ridge. In the buccal aspect, geometric form of mandibular molar is trapezoid while in proximal aspects it is rhomboid. The mesiodistal width of these teeth is much greater than the crown height. The buccal cups are blunt and often attrited. There are two buccal grooves on the 1st molar and single buccal groove on 2nd and 3rd molar. The buccal cervical ridge of the mandibular molar is more prominent, especially on the 1st molar.
What is the difference between Maxillary and Mandibular Molars?
Characteristics of Maxillary and Mandibular Molars
Maxillary molars: Maxillary molars have two buccal cups.
Mandibular molar: Mandibular molars have two or three buccal cups.
Maxillary molars: Maxillary molars have one buccal groove.
Mandibular molar: Mandibular molars have two on the first molar buccal groove.
Number of roots
Maxillary molars: Maxillary molars have three roots.
Mandibular molar: Mandibular molars have two roots.
Maxillary molars: Maxillary molars have a longer root trunk.
Mandibular molar: Mandibular molars have a shorter root trunk.
Cervix of crown
Maxillary molars: In Maxillary molars, Cervix of crown tapers more to lingual.
Mandibular molar: In Mandibular molar Cervix of crown tapers less to lingual.
Cups of Carabelli
Maxillary molars: Cups of Carabelli is commonly seen on the first molar in maxillary molar.
Mandibular molar: Cups of Carabelli are absent in mandibular molar:
Maxillary molars: Maxillary molar: crown is more centered over root.
Mandibular molar: Mandibular molar: crown is tipped more lingual over root.
Maxillary molars: Maxillary molar: Oblique ridge is present.
Mandibular molar: Mandibular molar: Oblique ridge is absent.
Maxillary molars: Maxillary molar has only one Transverse ridge.
Mandibular molar: Mandibular molar has two Transverse ridge.
Maxillary molars: Crown of the Maxillary molar is square shaped.
Mandibular molar: Crown of the Mandibular molar is pentagon shaped.
Maxillary molars: Maxillary molar has four; large central and cigar-shaped distal fossae.
Mandibular molar: Mandibular molar has three fossae; the central is the largest.Image Courtesy: “Upper jaw” by No machine readable author provided. Xauxa assumed (based on copyright claims). – No machine readable source provided. Own work assumed (based on copyright claims).(CC BY 2.5) via Wikimedia Commons “Lower jaw” by No machine readable author provided. Xauxa assumed (based on copyright claims). – No machine readable source provided. Own work assumed (based on copyright claims)..(CC BY 2.5)via Wikimedia Commons