maxillary first and second premolars

Distinguishing Maxillary 1st Premolars from Maxillary 2nd Premolars= Buccal View part three

Apical end of the root of all single-rooted premolars frequently bend distally (may be straight or bend mesially). Most of the time, 1st premolar is divided into buccal and lingual root splitting off a common trunk in the apical 1/3rd (Proximal view shows best). Buccal root normally longer than lingual root (frequently curves to the distal); so the lingual root may be straighter than the buccal or curved more to the mesial). Max. 2nd Premolar: single-rooted; longer root (nearly twice as long as the crown). Max. 2nd Premolar: greatest root-to-crown ratio of any maxillary tooth.

similarities to anterior teeth- lobes and facial crowns to cervical 3rd

4 lobes like canines/ exception 2nd mandibular premolar which has 5. The facial-crowns taper to be more narrow toward the cervical 3rd.

Distinguishing Maxillary 1st Premolars from Maxillary 2nd Premolars= Lingual View

Lingual cusps shorter on both premolars than the buccal (more so on 1st). Differences in marginal ridge heights are more apparent from the lingual view; mesial marginal ridges of both types of maxillary premolars are more occlusal in position than the distal marginal ridge. Lingual root of a 2-rooted Max. 1st premolar is usually shorter and narrower mesiodistally, than the buccal root. Narrow lingual root and broader longer buccal root-visible from lingual view.

premolar marginal ridges and occlusal table

MMR are generally more occlusal. DMR are generally more cervical. occlusal table or occlusal surface- MMR and DMR and cusp ridges merge.

Distinguishing Maxillary 1st Premolars from Maxillary 2nd Premolars= Proximal View part one

Max. 1st Premolars-have a UNIQUE prominent mesial crown concavity just cervical to the contact area. Max. 2nd Premolars-Do not. Important when restoring correct restoration (filling) contours AND when detecting and removing calcified deposits from this concave crown surface. Can see that buccal cusp is noticeably longer than the lingual cusp max. 1st premolars; max. 2nd premolars have cusps of nearly equal length.

Distinguishing Maxillary 1st Premolars from Maxillary 2nd Premolars= buccal view part two

Max. 2nd Premolars-have mesial cusp ridge of the BUCCAL cusp shorter than the distal cusp ridge.Max. 1st Premolar-UNIQUE: only premolar that has its mesial cusp ridge longer than the distal cusp ridge. Max. 1st Premolar-Buccal cusp long and pointed or sharp (Resembles adjacent canine). Max. 1st Premolar-buccal ridge is more prominent.

premolar traits- cusps, root, crown size and shape

Most premolars have one buccal cusp and one lingual cusp/ mandibular 2nd premolars have 2 lingual cusps. Shorter crowns on average vs. anterior teeth;1st premolar crowns slightly larger than 2nd premolar crowns. Roots slightly shorter than canines on each respected arch. crown shape-5 sided pentagon crown outline/facial view.

crowns of maxillary premolars

aligned more directly over their roots/ mandibular are not. proximal view: shaped like a trapezoid/ four sided figure with 2 parallel sides-occlusal and cervical, and 2 nonparallel sides. Buccal cusps is longer than lingual cusps, but minimal on maxillary premolars. Buccal ridge is more prominent.

similarities to anterior teeth- cervical line and root anatomy

cervical line curvature- when viewed from proximal is slightly greater on the mesial than distal (not as porminent as anteriors). 1 root premolar: convex on facial and lingual; taper apically. Apical 3rd of root often bent distally.

premolar terminology

facial surfaces of premolars can be referred to as buccal/ resting against the check side. occlusal surface. cusps. ridges. fossae. grooves.

what are the functions of the maxillary 1st and 2nd premolars?

function with molars to chew food, maintain vertical dimensions of the face, 1st premolars assist canines in shearing or cutting food, support corners of mouth and cheeks for support to keep them from sagging.

occlusal ridges, grooves, fossae

most cusps on posterior teeth have a triangular ridge that slopes toward the occlusal sulcus. premolars-most have 2 cusps that merge together called a transverse ridge. groove runs mesiodistally across occlusal surface from a mesial fossa to a distal fossa on most premolars. maxillary 1st and 2nd molars appear more alike.

distinguishing maxillary 1st premolars from maxillary 2nd premolars= buccal view part one

pentagon shape crown of max.1st premolar is larger than 2nd premolar, root is shorter on 1st premolar. 1st premolar: mesial and distal sides crown converge more noticeably from contact areas to the cervical line making it look more narrow, more prominent bulk where the cusp ridges join the proximal surfaces. More angular mesio-occlusal bulk and increased crown taper on maxillary 1st premolars.

premolar introduction, where are they positioned in mouth and from midline, how many are there, what are they similar to and how many lobes?

posterior teeth.pre-means before. positioned in front of the molars and posterior of the canines. 4th and 5th teeth away from the midline in each quadrant. 8 total premolars 4 maxillary. 4 mandibular. similar to the canine which has a labial ridge/ buccal ridge-premolar. 4 lobes/ 3 buccal + 1 lingual.

premolar traits- proximal contacts, views

proximal contacts from occlusal view are either on or slightly buccal to the faciolingual midline of the crown. Occlusal view: all types of premolars are normally wider faciolingually than mesiodistally. Buccal view: both proximal contacts generally more cervically located and more broad than anterior teeth; distal more cervical than mesial.

Distinguishing Maxillary 1st Premolars from Maxillary 2nd Premolars= Proximal View part three

Cervical Line Curvatures: Cervical line on the mesial side of both types of maxillary premolars curves occlusally in a broad, but shallow, arc. Mesial curvature is slightly greater than distal curvature. Cervical line on lingual surface may be more in an occlusal position than on the buccal surface (especially on maxillary 1st premolars)

Distinguishing Maxillary 1st Premolars from Maxillary 2nd Premolars= Proximal View part two

Crest of Curvature: Facial crest of max. premolars are at cervical 3rd (junction of cervical and middle 3rds). Lingual crest of max. premolars are more occlusal (in the middle third near the center of the crown). Helpful in distinguishing the buccal from the lingual surfaces. Marginal Ridge Grooves: Marginal ridge developmental groove (spillway for food during mastication). Seen extending across the marginal ridge and onto the mesial surface of a MAXILLARY 1st PREMOLAR (could extend from the mesial fossa or pit onto the mesial crown surface)

similarities to anterior teeth- contracts and when viewed from facial

Distal contacts are more cervical than the mesial contacts. viewed from facial-both M and D sides of the crown are convex.