Importance of Detection of
Developmental Age in Orthodontics.
Dr: Hany Salah Eid By
Mohamed MajedID: 58131
Growth is the increase in size. It may also be defined as the normal change in the amount of living substance. e.g. Growth is the quantitative aspect and measures in units of increase per unit of time. Human growth involves physical, mental, psychological, social & moral development.
It is the progress towards maturity. Development may be defined as natural sequential series of events between fertilization of ovum and adult stage.
Biological age or physiological age
The physiological age of a person is determined by the degree of maturation of the different tissue systems. Physiological age can be estimated by maturational status of somatic, sexual, skeletal, and dental system.
Annual growth increments in height or weight determines the somatic maturity. Measurement of height represents general growth of the skeleton. Average age of onset of stature growth for females and males of approximately 10 and 12 years, respectively, with the peak coming later in both sexes. Height, therefore, might represent a skeletal measure that can be used to predict the timing of the facial growth spurt and needs further exploration.
Growth modification attempt to change skeletal relationships by using the patient’s remaining
growth to alter the size or position of the jaws.
How does Growth modification work??
Three theories are offered: –
the first theory suggest that growth modification appliance change the absolute size of one or both jaws.
the second theory is that growth modification may work by accelerating the desired
growth but not changing the ultimate size or shape of the jaw.
the third possibility is that growth modification may work by changing the spatial relationship of the two jaws. The ultimate size of the jaw and its rate of growth are not changed, but by modifying the orientation of the jaws to each other, a more balanced profile may result.
When is the best time to begin orthodontic treatment?
Though an orthodontist can straighten teeth at any age, there is an optimal time period to begin jaw growth modification. Growth modification is best completed when the patient is still growing. We can take advantage of a child’s growing years by guiding proper jawbone formation using orthodontic appliances. This treatment can prevent malocclusions (bad bites) from forming or correct existing ones. Once the patient is an adult, surgery may be an option for correcting significant jaw misalignments.
The ideal time to start growth modification treatment varies from patient to patient. It is based on the stage of growth of the jaws and whether the jaw bones align in an underbite or an overbite.
advantages of interceptive growth modification treatment are:
Creates optimal facial symmetry
Fixes crowded teeth without tooth extractions
Corrects a crossbite
Corrects an open bite
Corrects an overbite
Corrects an underbite
When growth modification is utilized, a severe problem that would require surgery to fix at a later date can be fixed in a non-invasive and gentle way.
By utilizing growth modification, we can increase the self-esteem and confidence of a child since their teeth and jaw bones align better! This goes a long way in the junior high school years with our patients.
Cephalometric RadiographsA lateral cephalometric radiograph (LCR) is a standardized, reproducible radiograph used primarily for orthodontic diagnosis and treatment planning. It is taken from a distance of 1.5m with the head at a right angle to the X-ray beam at a distance of 30cm, A degree of magnification (around 8%) is expected and a scale may be incorporated to help calculate this. The cephalostat machine incorporates two posts which are placed in the external auditory meatus, the patient’s sagittal plane should be parallel to the X-ray film, the teeth in centric occlusion and the Frankfort plane is aligned horizontally.
Sagittal: A vertical plane passing through the standing body from front to back. The mid-sagital, or median, plane splits the body into left and right halves.
Sagittal Plane A.K.A. MEDIAN PLANE is an imaginary plane that passes longitudinally through the middle of the head and divides it into right and left halves. Used to describe anterior-posterior relationships.
SAGITTAL PLANE MALOCCLUSION
Pre-normal occlusion Where the mandibular dental arch is placed more posteriorly when the teeth meet in centric occlusion.
Post normal occlusion Where the mandibular dental arch is place more distally when the teeth meet in centric occlusion.
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