Unit 15 - Local and Contributing Factors Flashcards
Does local contributing factors initiate periodontal disease?
No
What is a disease site?
Indivudal tooth or specific surfaces of a tooth that are experiencing periodontal disease
What is the composition of calculus?
70-90% inorganic
Primarily calcium phosphate with small portions of calcium carbonate and magnesium phosphate
10-30% organic
Includes materials from biofilm, dead epithelial cells, dead white blood cells
May also include living bacteria within calculus deposits
Newly formed calculus deposit is called
Brushite
Mature but less than 6 month old calculus is primarily
Octocaclium phosphate
Calculus older than 6 months is primarily
Hydroxyapetite
The shape of subgingival calculus is usually
Flattened
What are the three modes of calculus attachement to the tooth surface?
Attachment to the pellicle
Attachment to the tooth irregularities
Attachment by direct contact to the tooth
What is the pellicle?
A thin, bacteria free membrane that forms on the surface of the tooth during late stages of eruption
What is the most common means of attachement for calculus to the enamel surfaces?
Attachment to the pellicle
Why are calculus deposits attached to the pellicle removed easily?
Because attachment is on the surface of the pellicle, not looked to the tooth
Where does calculus attach when classified as attachement to irregularities in the tooth surface?
Cracks in the tooth
Tiny openings in from the PDL detachment
Grooves in the cementum from over-instrumentation
Why is attachment to irregularities in the tooth surface calculus difficult to remove?
Because deposits lie sheltered in tooth defects
How does calculus attach to the tooth surface?
The matrix of calculus deposit may interlock with inorganic crystals of the tooth
Why is calculus attached to the tooth surfae difficult to remove?
Deposits are firmly interlocked in the tooth
What are the surface features of a tooth that may cause tooth morphology related increased plaque retention?
Tooth grooves or concavities
Cervical enamel projections and enamel pearls
Malocclusion
Dental caries
Orthodontic appliances
What is a developmental groove on the palatal surface of a tooth called?
Palatogingival groove
Some dental treatments may contribute to oral disease known as iatrogenic factor. Some examples are:
Overhanging margin
Open margin
Open contact
Poorly contoured crown
Orthodontic appliances
Poorly designed dental prosthesis
If a crown margin is closer than 2mm to the alveolar crest it can result in
Bone resorption
What are factors / causes of direct damage to the periodontium?
Food impaction
Improper use of plaque control aids
Tongue thrusting
Mouth breathing
Traumatic toothbrushing
Oral jewelry and body piercings
Trauma from occlusal forces
Parafunctional occlusal forces
Signs of trauma from occlusion
Tooth mobility
Sensitivity to pressure
Migration of teeth
Enlarged, funnel-shaped PDL space
Alveolar bone resorption
What is secondary occlusal trauma?
Injury to the periodontium from normal occlusal forces applied to a periodontium previously damaged by periodontitis
