Middy Flashcards
What are the characteristics of an ideal alveolar ridge?
- Proper jaw relationships
- Proper configuration of alveolar process (board U shape)
- No bony or soft tissue protuberances or undercuts
- Adequate attached keratinized mucosa in the primary denture bearing area
- Adequate vestibular depth (BL)
- Adequate bone height & width
- Fixed tissue under dentures
- No obstructing arena or scar bands
- No displacing muscle attachments
When a tooth is no longer situated in alveolar bone, what happens to the alveolar bone?
- Immediate change starts following tooth loss due to lack of function stress from the PDL (PRIMARY CAUSE)
-the bone atrophies but muscle attachments remain in the same place leading to:
1. lack of floor of mouth on lingual side
2. lack of vestibular depth on buccal side
What is the primary cause of Immediate change of alveolar bone following tooth loss?
Lack of functional stress from PDL
Describe bone resorption from one person to another-
unpredictable- in some it is stabilized and in others you can have total loss of alveolar and underlying basal bone
Which arch resorbs more quickly following extraction?
mandible
What component of the maxilla resorbs most quickly following extractions?
hamular notch
Increasing the quantity or quality of bone or soft tissues in the edentulous areas of the oral cavity:
vestibuloplasty
The purpose of a vestibuloplasty is to reposition the alveolar mucosa and muscle insertions more ____ to gain ____.
apically; vestibular depth
Another name for vestibuloplasty:
relative ridge augmentaiton
Vestibuloplasty increases:
- surface area of fixed tissue for denture support
- depth of vestibules for denture flange extension
- depth of sulcus for healthy, firm soft tissue coverage of the ridge, and adequate bony support for the denture
Indications for performing a RELATIVE alveolar ridge augmentation:
- flat ridge with MODERATE resorption of alveolar bone
- 2 cm or MORE of bone present at the mid-body of the mandible
Where will height be increased for a RELATIVE alveolar ridge augmentation?
symphysis and mid-body regions
Indications for performing an ABSOLUTE alveolar ridge augmentation:
- flat ridge with EXTREME resorption of alveolar bone
- BONE GRAFTING is done to increase the bone height
- LESS THAN 2CM of bone at mid-body of mandible
If we have LESS THAN 2 cm of bone at mid-body of mandible, this indicates:
ABSOLUTE alveolar ridge augmentation
Where can you procure bone for the AUTOLOGOUS bone graft to maxilla/ mandible?
Iliac crest
Describe bone resorption in the maxilla:
Buccal-palatal resorption (width)
Maxillary resorption = width
(also tend to get hyper mobile soft tissue)
Describe bone resorption in the mandible:
SUPI
Superior-inferior resorption (height)
More bone resorption in mandible
Bone resorption is enhanced by:
- surgery
- denture wearing
- low mandibular plane angle
What deficiency may accelerate bone resorption?
Vitamin D and calcium deficiency
What systemic diseases may accelerate bone resorption?
- osteoporosis
- endocrine dysfunction
- other conditions
List the possible causes of tooth impactions:
- inadequate arch lenght
- prolonged deciduous tooth retention
- malposition of impacted tooth
- excessive bone or soft tissue
- malposition of adjacent tooth/teeth
- associated pathology (3rd molars)
What is the most common cause of tooth impaction?
malposition of impacted tooth
Which teeth are most likely to become impacted (in order)
- mandibular 3rd molars
- maxillary 3rd molars
- maxillary canines
- mandibular premolars
- mandibular canines
- maxillary incisors
- supernumeraries
If a MAXILLARY TOOTH is impacted, what position/orientation is it typically located in?
Vertical impaction
If a MANDIBULAR TOOTH is impacted, what position/orientation is it typically located in?
mesioangular impaction
What is the most difficult position of an impacted tooth for removal?
distoangular