Islamic Teachings and Dental Anatomy

Islamic Teachings on Accountability

• A person's journey on the Day of Judgment will not end until being questioned about four things:
  • How they spent their life
  • The state of their body
  • Their knowledge and how they used it
  • How they acquired and spent their wealth

Maxillary Central Incisor

• The maxillary central incisor is the broadest tooth in the anterior set.
• It's the only tooth in the dental arch where the mesial surfaces of the upper and lower teeth are contact.
• Maxillary central incisor has five aspects: Labial, lingula, mesial, distal, and incisal.

Diastema

• A space occurs between the central incisors
• The dental arch is wider on the facial/labial side compared to the lingual side

Tooth Numbering Systems

• There is a Universal Tooth Numbering System
• There is also a Palmer/Zsigmondy System

Tooth Development/Chronology

• Different stages of tooth development are associated with specific age ranges.
  • First evidence of calcification: 3-4 months
  • Enamel completed: 4-5 years
  • Eruption: 7-8 years
  • Root completed: 10 years

Maxillary Central Incisor Aspects

• The maxilla central incisor has five aspects:
  • Labial
  • Lingual
  • Mesial
  • Distal
  • Incisal

Labial Surface

• The crown's outline is trapezoidal.
• The shortest side of the trapezoidal crown is oriented towards the cervical area.

Mesial Outline

• Slightly convex
• The crest of curvature is near the incisal ridge, almost at the middle one-third of the incisal.
• The mesioincisal angle is sharp
• The mesial contact area is represented.

Distal Outline

• More convex.
• The crest of curvature is at the cervix.
• The distoincisal angle is rounded.
• The distal surface's contact area is represented.

Incisal Outline

• The incisal outline is usually perpendicular to the tooth's long axis.
• The root outline is cone-shaped, ending in a blunt apex.
• The crown outline is usually trapezoid (with the shorter side near the cervix).

Cervical Outline

• Convex on root side.
• Concave on the crown side.

Lingual Surface

• The tooth converges lingually (tapers towards the lingual aspect).
• The lingual surface is narrower than the labial surface.
• The facial dental arch is wider compared to the lingual arch

Lingual Surface Elevations

• Cingulum at the cervical one-third.
• Mesial and Distal marginal ridges.
• Incisal ridge

Lingual Surface Depressions

• M-shaped lingual fossa.

Mesial Surface

• The crown's outline is wedge-shaped or triangular.
• The base of the triangle is at the cervix.
• apex is at the incisal ridge.

Mesial Outline

• The labial outline is convex, and the crest of curvature is at the center of the cervical third, representing the cervical ridge.
• The lingual outline is mostly convex in the cervical one-third, representing the cingulum, then becomes concave in the middle third, and has a slight convexity toward the incisal region indicating the incisal ridge.
• The incisal ridge is at the same line as the root's apex.

Distal Surface

• The distal surface is the reverse of the mesial surface.
• The crown appears thicker at the incisal one-third.
• The cervical line curvature is less than the mesial curve (by 1mm).

Incisal Aspect

• The crown is broader mesiodistally than labiolingually.
• The labial outline is broader and flatter compared to the lingual one.
• The incisal edge, roughly in the center of this aspect.
• The fossa is lingual to the incisal edge, and is bordered by strong mesial and distal marginal ridges.

Pulp Cavity

• To study the pulp you need longitudinal and cross-sectional views of the tooth.

Pulp Chamber

• Mesio-distal section: Trapezoidal (wide incisally, narrow cervically).
• Three pulp horns are apparent in young teeth (they disappear with age).
• Labio-lingual section: Triangular, pointed incisally, and wide cervically.

Root Canal

• Single and straight, with apical tapering.
• Oval cross-section.