Fundamental & Preventive Curvatures Flashcards
Define Proximal Contact Area
areas on the surfaces of the teeth where the proximal surfaces touch one another
Purposes of curvatures
- Prevent disease
- Prevent damage
- Prevent bacterial invasion
- Prevent calculus build-up
- Disperse excessive occlusal force
- Protect the gingiva and periodontium
- Preserve the teeth, increasing life expectancy & productivity
Define Alignment
Refers to the way teeth are positioned in the jaw
Define Contact Area
flattened portion of the tooth where it actually touches the next
tooth in the same arch
Purpose of Contact Area
- Prevention of food impaction
- Help teeth offer support and anchorage to one another
- Adjacent teeth share interproximal bone - Help resist displacement from traumatic forces
Location of Contact Area
- Mesial and distal surfaces of each tooth
- occur at the widest portion and the greatest curvature
of the proximal surfaces - Distal of one tooth touches the mesial of the tooth
posterior to it - Central incisors - two mesial surfaces touch each other
Specific Locations Contact Area ( Facial View )
- Anteriors - closer to incisal
- Posteriors - more cervical
- The more posterior you go, the more cervical the contact…EXCEPT…Mn 1st
- Premolar - mesial contact is more cervical than distal contact, mn
- Central - contact area is the same mesial and distal
- The more posterior you go, the wider the contact area
Specific Locations Contact Area ( Occlusal View )
- Anterior - center of the proximal surface
- Posterior - facial, buccal to the center of the proximal surface
Define Contact Points
areas where the occlusal cusp of one tooth touches the occlusal portion of another tooth from the opposite arch
Define Interproximal Spaces
triangular-shaped spaces/ V-shaped spaces between teeth
Boundaries (Interproximal Spaces)
- Contact area from the apex
- Proximal surfaces form the lateral border
- Alveolar bone form the base
Functions (Interproximal Spaces)
- Preventive
- Provides a place for the bulk of the bone for better anchorage and support
- Provides vascular support to nourish the bone and tissue
Interdental papilla / papillary gingiva - gingival tissue filling in the Interproximal spaces
- In health interdental papilla fill in the space
- Helps to keep food from collecting in between the teeth
Define “Cervical” embrasure
Void caused by loss of bone and gingiva.
- Creates an area for accumulation of bacteria, calculus, and food debris
Characteristic (Interproximal Spaces)
- Shorter as you go posteriorly
Define Embrasures
spaces between the teeth that are occlusal to the contact area
Function (Embrasures)
- Allow passage of food around teeth
- Reduce force of occlusal trauma by dissipating occlusal force
- Self-cleansing
- Protect the gingiva and allows gingival stimulation
Poor contour leads to gingival irritation
Naming embrasures
- Lingual, palatal - spaces lingual to contact area
- Incisal, occlusal - spaces incisal or occlusal to contact area
Gingival/ Cervical Embrasures
gingival to the contact area
Characteristics (Embrasures)
- Wider as you go posteriorly
- Lingual embrasures are wider than facials
Function (Facial and Lingual Contours)
- Direct food off teeth and against the gingiva at a proper angle
- Cleansing also occurs by tongue, lips, & cheek
Height of contour/crest of curvature
location of the widest part
of the crown of the tooth.
1. Facial
a. anterior - cervical 1/3rd b. posterior - cervical 1/3rd
2. Lingual
a. anterior - cervical 1/3 rd b. posterior - middle 1/3rd
Curvature of the CEJ
A. Line where the cementum & the enamel meet
B. Also called the cervical line
C. Proximal Curvature
D. Facial/Lingual Curvature - curves toward the apex of the root
- Proximal aspect - toward the incisal/occlusal, convex curve coronally
- Depends on the height of the contact & the width of the tooth faciolingually
- More anterior - the greater the curvature
- Mesial curvature is greater than the distal, generally 1mm less on the distal
Restorative Dentistry
A. Must reproduce contours
1. Too much contour - food won’t touch the gingiva
2. Too little contour - food hits gingiva too much, resulting in recession
B. Open contacts/light contacts - teeth do not touch as they should
1. Causes food impaction between the teeth
a. Papilla destroyed
b. Bone loss occurs
C. Margins
1. Overhanging margin, restoration is not flush with the tooth,
but extends beyond the tooth; causes plaque, bacteria, food retention
2. Rough surfaces of restorations cause increase plaque
retention, recurrent decay, mechanical irritation
Marginal Ridge Contours
A. Adjacent teeth - heights should be relatively the same
B. Occlusal embrasures should be small in order to act as spillways for self-cleansing
Posterior Central Grooves
A. Groove aligns into one linear groove
B. One trough anterior-posteriorly down the center of the occlusal
surface for efficient mastication
C. Help with distribution of forces during chewing
