Morphology.txt

anatomical alignment between the maxillary and mandibular teeth and their relationship to the rest of the masticatory system.

• (aka ICP)
• position of maximum intercuspation between the maxillary and mandibular teeth.

• Orthodontic classification
• Based on the ICP relationship between the 1st molars from the facial view.
• Canines are used when the 1st molars are missing.
• Angle Class I, II, or III

• Canines are used when the 1st molars are missing.
• The MB cusp of the maxillary 1st molar aligns with the buccal groove of the mandibular 1st molar.

The MB cusp of the maxillary 1st molar aligns MESIAL to the buccal groove of the mandibular 1st molar.

The MB cusp of the maxillary 1st molar is DISTAL to the buccal groove of the mandibular 1st molar.

Vertical Overlap of anterior teeth

Horizontal overlap of anterior teeth

reciprocal and simultaneous contact of opposing supporting cusps in ICP.

• Premolar buccal and molar MB cusps make marginal ridge(occlusal embrasure) contacts called dipod contacts (D).
• The DB cusps of mandibular molars make fossa contacts called tripod contacts (T).

• Premolar lingual cusps make fossa contacts in the distal fossa of the opposing mandibular premolar.
• Molar ML cusps make fossa contacts in the central fossa of opposing mandibular molar.

• Well-distributed posterior contacts
• Coupled contacts between opposing teeth
• Overall tripoding of each tooth

• Bacterial in origin
• Highly preventable
• -Regular professional care
• -Good oral hygiene
• -Public health measures

• Group of infectious or inflammatory diseases that damage the periodontal (supporting) tissues
• 

• Demineralization and loss of calcified tooth tissues
• Occlusal pits and fissures are sites commonly affected.
• Lost tooth structure restored by ‘fillings’
• Untreated caries may lead to pulp infection
• 

• Concavities, grooves, furcations
• Anatomical Factors Requiring Consideration During Periodontal Tx
• Furcations
• Root grooves
• Crown contours in gingival third

• location on a multirooted tooth where the root trunk divides into separate roots
• trifurcation, bifurcation
• 

Number of roots and canals/root

• Loss of proximal contacts
• Unstable ICP
• Supraeruption
• Mesial drift
• 

• 1st non-succedaneous tooth ... oldest
• 

• Mandibular Canine
• Labial-Lingual roots
• 

• Proximal contacts
• -Correct size and location
• Embrasure form
• -Symmetry and size
• Marginal ridge height
• -Same on adjacent teeth
• Crown contours
• -Especially in cervical third
• Occlusal stability
• -Well distributed ICP contacts
• -Forces along long axis of each tooth

• Tooth surfaces involved
• Location on each surface
• Distance from CEJ
• Ex: Mandibular 1st Molar
• There are buccal and lingual furcation entrances.
• Both are centered on that surface.
• Distance from CEJ:
• buccal = 3 mm
• lingual = 4 mm
• 

• There are buccal and lingual furcation entrances.
• Both are centered on that surface.
• Distance from CEJ:
• buccal = 3 mm
• lingual = 4 mm
• 

• *The mesial furcation entrance of a maxillary molar is located 2/3 of the distance from buccal to lingual on the mesial surface.
• 

• Lingual of maxillary lateral incisor
• Root surfaces of mandibular anteriors
• Distal of maxillary canine
• Mesial of maxillary first premolar

• Prominent on distal root surfaces of mandibular anterior teeth
• 

• Note concavities on crown surfaces gingival to contact.
• 

• Max 1st premolar (lots of concave areas)
• 1.Longitudinal root grooves
• 2.Mesial Marginal Developmental Groove
• 3.Mesial Crown Concavity
• 4.Bifurcation

• 1.Proximal contacts (correct size and location)
• ** correct embrasure size and proximal contact (not too buccal/lingual) Between #4 and #5
• 
• 2.Embrasure form (symmetry and size)
• ** gingival embrasure form - overhang exists (large open surface going towards the occlusal surface; overflossing)
• 
• 3.Marginal ridge height (same on adjacent teeth)
• 4.Crown contours (especially in cervical third)
• ** contour is insufficient/flat; needs more in cervical third on the buccal
• 
• 5.Occlusal Stability (well distributed ICP contacts; forces along long axis of each tooth)
• 6.Faulty Dentistry
• *** 8 and 9 crowns producing inflamed gingival tissue (crowns too Bulbous -> irritating gums
• 
• Overhangs
• 

• 6% of mandibular canines have two root canals.
• 

• 60% of maxillary 1st molars have two canals in the MB root.
• 

• 30% of mandibular 1st molars have two canals in the distal root.
• 

• In LEFT Laterotrusion, the RIGHT Condyle moves anteriorly.
• The Mediotrusive condyle moves anteriorly.
• Therefore mandibular pathways on mediotrusive side have an posteriorly angled direction.
• Angle is more distal for more posterior teeth.
• The laterotrusive condyle stays is the pivot point.