Dental Anatomy and Masticatory Dynamics

George Washington’s ‘Teeth’

20 th century dentures

Restorative Dentistry on typodont

Masticatory / Gnathological System

Masticatory / Gnathological system Masticatory: –Pertaining to chewing Gnathology –Science that deals with anatomy, histology, physiology, pathology of the jaws and masticatory system as a whole, including the applicable diagnostic, therapeutic and rehabilitative procedures Frontal view

Sagittal view of skull: Jaws: Maxilla – non-movable Mandible - movable Temporomandibular jt

Mixed Dentition: Primary /Deciduous and Permanent

Determination of age from teeth present

6 year molar LI + CI 8 yr 7 yr LI + CI 8 yr 7 yr

Permanent Teeth

Maxillary ANTERIOR Mandibular ANTERIOR

Anterior Teeth Maxillary –Central Incisor (2 – right and left) –Lateral Incisor (2 – right and left) –Canine (2 – right and left) Mandibular –Central Incisor (2 – right and left) –Lateral Incisor (2 – right and left) –Canine (2 – right and left)

Maxillary PreMolars Mandibular PreMolars

Posterior Teeth - PreMolars Maxillary –1 st Premolar (2 – right and left) –2 nd Premolar (2 – right and left) Mandibular –1 st Premolar (2 – right and left) –2 nd Premolar (2 – right and left)

Maxillary Molars Mandibular Molars

Posterior Teeth - Molars Maxillary –1 st Molar (2 – right and left) –2 nd Molar (2 – right and left) –3 rd Molar (Wisdom tooth) (2 – right and left) Mandibular –1 st Molar (2 – right and left) –2 nd Molar (2 – right and left) –3 rd Molar (Wisdom tooth) (2 – right and left)

Division Arches –Maxillary Mandibular Quadrants –Maxillary Arch Mandibular Arch Right quadrant Left quadrant Sextants –Maxillary Arch Mandibular Arch Right posterior sextant Anterior sextant Left posterior sextant

Maxillary Arch

Left RIGHT LEFT

Maxillary Arch Max Right quadrant

Maxillary Arch Max Left quadrant

Maxillary Arch Max Left Posterior sextant Max Right Posterior sextant

CROWN coronal ROOT radicular Cervical line

Incisal (ant) Occlusal (post) CROWN coronal ROOT radicular APEX apical Cervical line

Right Midline Left

Mesial – towards midine Distal Away from midline

Right Midline Left M D M D

Right Left missing missing 16 UNIVERSAL SYSTEM

Mandible numbering system 32 missing missing /24 23

Name / number the teeth Using Universal # System

Name / number the teeth Using Universal # System!

8 9

More terminology FACIAL View

More terminology Views / aspects of teeth –Facial –Lingual –Mesial (a proximal surface) –Distal ( a proximal surface) –Occlusal (posterior) / Incisal (anterior)

# 8 Facial View INCISAL MESIAL DISTAL midline

Apical Facial View Mesial Distal Incisal

Apical Mesial Distal Incisal APICAL MIDDLE CERVICAL MIDDLE INCISAL

Apical Mesial Middle Distal Incisal middle Mesial Middle Distal

Apical Facial Middle Lingual Cervical Facial Middle Lingual Incisal Proximal View

Proximal Facial Incisors PM Molars Trapezoid Rhomboid Triangle

Facial of all teeth - trapezoidal

Contact areas Area on proximal surface of a tooth – either M or D – when teeth are in good alignment – which touches adjacent tooth

Contact areas Area on proximal surface of a tooth – either M or D – when teeth are in good alignment – which touches adjacent tooth

Variations yet characteristics for identification

Maxillary Incisors Purpose Along with mandibular incisors –Esthetics –Phonetics - speech –Incising / cutting

Information* and Photos with black background – Tooth Atlas * Information with asterisk from Tooth Atlas CD

Maxillary Central Incisor Development* The initiation of calcification is between 3 and 4 months. The completion of enamel formation is 4 to 5 years. The eruption is between 7 to 8 years. Root development complete at 10 years.

Why DA ?

5 views of teeth Facial –Labial (anterior) –Buccal (posteriors) Lingual Mesial Distal Incisal / Occlusal –Ant / posterior

Maxillary Central - #8 - Facial view Crown:Root - 11mm: 13 mm M-Inc Corner - 90 degrees D-Inc Corner - rounded M contact - Incisal D contact - Junction (Incisal/Middle) D M

Maxillary Central - #8 - Facial view Size –MD widest ANT tooth –Inc-Cerv longest Crown M outline straight D outline sltly rounded

Maxillary Central - #8 - Facial view Size –MD widest ANT tooth –Inc-Cerv longest Crown M outline straight D outline sltly rounded

Maxillary Central - #8 - Lingual view Marginal ridges (MR) –MMR > DMR –Moderately pronounced Cingulum –Moderately pronounced –D located Fossa –Moderate depth

Maxillary Central - #8 - Lingual view Marginal ridges (MR) –MMR > DMR –Moderately pronounced Cingulum –Moderately pronounced –D located Fossa –Moderate depth

Maxillary Central - #8 - Mesial view Incisal Edge sltly F to. root axis Facial surface flat CEJ (cervical line) deeper on M Root: –M surface – flat w/ depression –(D surface – convex w/ no depression)

Maxillary Central - #8 - Distal view Incisal Edge sltly F to. root axis Facial surface flat CEJ (cervical line) deeper on M Root: –M surface – flat w/ depression –(D surface – convex w/ no depression)

Maxillary Central - #8 - Incisal view Geometric –Triangular –MD > FL – Facial –flat Cingulum –Distal location

Maxillary Lateral Incisor Most variable ANTERIOR tooth

Maxillary Lateral - #7 - Facial view Crown:Root - 10mm: 13 mm M-Inc Corner - rounded D-Inc Corner - v. rounded M contact - Junction* D contact - Middle *(Incisal/Middle)

Maxillary Lateral - #7 - Facial view Crown:Root - 10mm: 13 mm M-Inc Corner - rounded D-Inc Corner - v. rounded M contact - Junction* D contact - Middle *(Incisal/Middle)

Maxillary Lateral - #7 - Facial view Size –MD smaller than CI –Inc-Cerv shorter CI M outline rounded D outline v. rounded

Maxillary Lateral - #7 - Facial view Size –MD smaller than CI –Inc-Cerv shorter CI M outline rounded D outline v. rounded

Maxillary Lateral and Central - #7 - #8 - Facial view

Maxillary Lateral - #7 - Lingual view Marginal ridges (MR) –MMR > DMR –Moderately pronounced –More than CI Cingulum –More pronounced than CI –Centered Fossa –Moderate depth –Pits / groove variation

Maxillary Lateral - #7 - Lingual view Marginal ridges (MR) –MMR > DMR –Moderately pronounced –More than CI Cingulum –More pronounced than CI –Centered Fossa –Moderate depth –Pits / groove variation

Maxillary Lateral - #7 - Mesial view Incisal Edge sltly F to. root axis Facial surface more rnd CEJ (cervical line) deeper on M Root: –M surface – flat w/ depression –(D surface – flat / no depression)

Maxillary Lateral - #7 - Distal view Incisal Edge sltly F to. root axis Facial surface more rnd CEJ (cervical line) deeper on M Root: –M surface – flat w/ depression –(D surface – flat / no depression)

Maxillary Lateral - #7 - Incisal view Geometric –Rnded –MD > FL – Facial –rnd Cingulum –Centered

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