Introduction to orthodontics Flashcards
What is orthodontics?
Branch of dentistry concerned with facial growth, dentition development and occlusion, and with the diagnosis, interception and treatment of occlusal anomalies.
During which stage of development may developmental abnormalities be identified ?
Mixed dentition (ages 6-13)
What type of radiograph is used to investigate possible development abnormalities e.g. ectopic teeth?
OPT
Possible causes of ectopic teeth
Supernumerary tooth blocking eruption pathway, or displacement of tooth germ due to trauma
How can an ectopic tooth be surgically exposed?
Using a metal gold plate to pull downwards on the tooth
Type of malocclusion where an upper anterior tooth is posterior to the lower anterior teeth
Anterior crossbite
Why should an anterior crossbite be resolved ASAP?
Anterior crossbite may cause enamel wear due to attrition, gum recession and mobile teeth
What is an increased overjet?
Type of malocclusion where upper anterior teeth protrude more than 4 mm infront of lower anterior teeth
What is overjet?
Horizontal distance between upper and lower incisors. normal overjet is 2-4mm
What is a reverse overjet?
type of malocclusion where lower incisors protrude infront of upper incisors. (may be the case in class III)
Which AP jaw relationship is more likely to cause a reverse overjet?
Class III
What is a posterior crossbite?
Type of malocclusion where the buccal cusps of the lower posterior teeth occlude buccally to the buccal cusps of the upper posterior teeth.
How does the arch length increase to accommodate for the 6, 7, 8?
Arch length increases posterior to first deciduous molar (not infront)
What is the Leeway space?
The difference in mesio-distal diameter between c, d, e and 3, 4, 5
How much greater is the Leeway space of the deciduous dentition in the maxilla?
1.5 mm