1. health and fitness
2. disease

11
CH 27 MANAGEMENT OF THE
DEVELOPING OCCLUSION (I)
DEVELOPMENT OF THE OCCLUSION
PREVENTIVE MANAGEMENT OF THE DEVELOPING OCCLUSION
McDonald, Avery, Dean. Dentistry For The Child And Adolescent, 8th Ed.
Page: 625-683
Tuesday 17/2/1436 H
9\12\2014
1:00 pm-2:00 pm
1
OTHMAN AL-AJLOUNI
CHAPTER OUTLINE
1. DEVELOPMENT OF THE OCCLUSION
2. PREVENTIVE MANAGEMENT OF THE
DEVELOPING OCCLUSION
3. INTERCEPTIVE ORTHODONTICS
4. COMPREHENSIVE ORTHODONTICS
FOR THE DEVELOPING OCCLUSION
PREREQUISITE KNOWLEDGE
1. Growth and development of face and
jaws both prenatal and postnatal
2. Eruption of teeth timing and sequence
3. Morphology of teeth both primary and
permanent
4. Terminology of key words
5. Masticatory movement and path of
closure of the mandible
OBJECTIVES
You should be able to answer the following questions at the end of this lecture
1. To
recognize,
differentiate,
and
either
appropriately manage or refer abnormalities in
the developing dentition.
2. Early diagnosis and treatment of developing
malocclusions to achieve occlusal harmony,
function, and dental facial esthetics.
3. To
discuss
current
concepts
in
space
maintenance for the pediatric patient.
4. An overview of interceptive and comprehensive
orthodontic care for the primary, mixed, and
early permanent dentition.
DEVELOPMENT OF THE OCCLUSION
TWO FORMS OF PRIMARY DENTITION:
Type I: spaces between teeth were present at
all stages or
Type II: teeth were in proximal contact at all
stages (40%).
Spacing in primary dentition is apparently
congenital rather than developmental.
PRIMATE, SIMIAN OR ANTHROPOID
SPACES:
Spaced arches exhibit two diastemas: Mesial
to maxillary canine and distal to mandibular
canine.
DEVELOPMENT OF THE OCCLUSION
From 4 years of age until eruption of
permanent molars SAGITTAL dimensions of
dental arches remained unchanged.
A slight decrease in this dimension can occur
either as a result of
mesial migration of primary second molar
just after eruption or
after
development of dental caries on
proximal surfaces of molar teeth.
Only minor changes in the TRANSVERSE
dimension of the maxillary and mandibular
primary arches occurred during period from
3 1/2 to 6 years of age.
.
DEVELOPMENT OF THE OCCLUSION
PRIMARY MOLARS (Terminal Plane) RELATIONSHIP
A. STRAIGHT (FLUSH) TERMINAL:(37%)
Plane with primate space; an early shift of
mandibular molars into the primate space allows
proper first permanent molar occlusion (early shift).
Plane without primate space; proper first
permanent molar occlusion is not attained until
mandibular second primary molar exfoliates, which then allows desirable
mesial shift of mandibular first permanent molar (late shift)
B. DISTAL STEP:(14%)
Distal surface of lower E distal to upper E, result in class II permanent
molars relationship
D. MESIAL STEP: (49%)
Distal surface of lower E mesial to distal surface of upper E, allows first
permanent molar to erupt into proper occlusion class I.
.
DEVELOPMENT OF THE OCCLUSION
TYPICAL FEATURES OF OCCLUSION OF PRIMARY
DENTITION:
1. SPACING
2. TERMINAL PLANE
3. DEEP BITE
4. WIDE DENTAL ARCHES
5. FLAT CURVE OF SPEE
6. SHALLOW CUSPAL INTERDIGITATION
7. VERTICAL PLACED INCISORS
8. EACH MAXILLARY TOOTH OCCLUDE WITH
TWO MANDIBULAR TEETH
STAGES OF DEVELOPMENT OF THE OCCLUSION
AT TIME OF ERUPTION OF PERMANENT INCISORS
A transverse widening of mandibular arches
by lateral and frontal alveolar growth.
Increase in intercanine width was greater in
Maxillary arch than in mandibular arch.
It occurred during eruption of lateral incisors in mandible
and in maxillary arch during eruption of central incisors.
Spaced primary arches generally produced favorable
alignment of permanent incisors, whereas about 40% of
arches without spacing produced crowded anterior
segments.
DIAGNOSTIC RECORDS AND ANALYSIS
1. E/O and I/O photographs: an eight-film series of extraoral and
intraoral photographs
2. Diagnostic dental casts: trimmed orthodontic study models
3. I/O and panoramic radiographs: a full-mouth series or OPG
4. Lateral and AP cephalograms: cephalometric analysis
5. Other diagnostic views (magnetic resonance imaging, computed
tomographic
scans)
when
indicated,
appropriate
temporomandibular diagnostic views such as corrected axis
tomograms or magnetic resonance imaging.
Patient's neuromuscular growth and nasopharyngeal airway must be
assessed. Patients who are mouth breathers secondary to hypertrophic
adenoid tissue or allergic conditions can influence developing skeletal
face. Appropriate referral to pediatrician or otolaryngologist for further
assessment.
ARCH-LENGTH ANALYSIS
SPACE ANALYSIS: A comparison of available arch length
to predicted size of unerupted permanent canines and
premolars (required arch length) at a given point in time.
INDICATIONS OF MIXED DENTITION ANALYSIS
1. To determine need for space maintenance
2. To determine need for minor tooth movement
3. To aid in determining approach for minor tooth movement
4. To evaluate need for guided eruption procedures
5. To determine need for orthodontic referral:
a. Comprehensive orthodontics
b. Serial extraction
ARCH-LENGTH ANALYSIS
1. NANCE ANALYSIS.
Leeway space of Nance: 1.7 mm per side in mandible = (mesiodistal widths) primary canine and
first and second primary molars - responding permanent teeth(3+4+5).
Leeway space of Nance: 0.9 mm per side in maxilla.
Seldom used, partly because is require a complete set of periapical radiographs.
2. MOYERS MIXED DENTITION ANALYSIS.
In mouth & on casts, and for both arches.
Based on correlation of tooth size; measure a tooth or a group of teeth and predict accurately
size of other teeth in same mouth. The mandibular incisors measurement to predict size of
upper, as well as lower, posterior teeth, using prediction table.
3. TANAKA AND JOHNSTON ANALYSIS.
Prediction table is not. sum of widths of mandibular permanent incisors divided by 2. For lower
arch, 10.5 mm is added to result and, for upper arch, 11 mm is added to result to obtain the total
estimated widths of the canines and premolars. Hixon and Oldfather method is more accurate
4. BOLTON ANALYSIS.
(Sum mandibular)/(Sum maxillary) x 100 = Tooth mass ratio, For overall ratio (12 teeth versus
12 teeth), the mean is 91.3 (±1.91)%. For anterior ratio (6 teeth versus 6 teeth), the mean is
77.2 (±1.65)%.
When significant discrepancy present, tooth mass is a problem solved by slenderization of
anterior teeth or bonding to increase mesiodistal width of lateral incisors.
PLANNING FOR SPACE MAINTENANCE
Factors influence development of a malocclusion:
1. Abnormal oral musculature. High tongue position coupled with a
strong mentalis muscle may damage occlusion after loss of a
mandibular primary molar. A collapse of lower dental arch and distal
drifting of anterior segment.
2. Oral habits. Finger habits cause abnormal forces on dental arch and
are responsible for initiating a collapse after untimely loss of teeth.
3. Existing malocclusion. Arch-length inadequacies and other forms of
malocclusion, particularly class II, division 1, usually become more
severe after untimely loss of mandibular primary teeth.
4. Stage of occlusal development. In general, more space loss is likely
to occur if teeth are actively erupting adjacent to space left by
premature loss of a primary tooth.
PLANNING FOR SPACE MAINTENANCE
Factors Are Important When Space Maintenance Is
Considered After The Untimely Loss Of Primary
Teeth:
1. Time elapsed since loss.
2. Dental age of the patient.
3. Amount of bone covering the unerupted tooth.
4. Sequence of the eruption of teeth.
5. Delayed eruption of the permanent tooth.
FACTORS RELATED TO ARCH-LENGTH ADEQUACY
BEFORE PLACING S.M. EVALUATE:
1.
2.
3.
4.
5.
Arch Length
Degree Of Crowding
Amount Of Space Needed
Size Of Unerupted Teeth
Depth Of Curve Of Spee.
Arch circumference (arch length),
distance from mesial surface of first
permanent molar on one side to mesial
surface of first permanent molar on
opposite side.
15
THE BAND OR SSC AND LOOP MAINTAINER
Not restore chewing function and
Not prevent eruption of opposing
teeth
Loop
allow
eruption
of
permanent tooth.
0.036-inch (0.9mm) minimum
steel wire.
Bilateral
band
and
loop
maintainers before eruption of
permanent incisors.
DISTAL SHOE APPLIANCE
Appliance with a distal intragingival extension, to maintain
space or influence active eruption of first permanent molar in
a distal direction.
Positioning of tissue extension determined with dividers and
a bite-wing radiograph, tissue-bearing.
Before final placement radiograph. not necessary to be in
direct contact with permanent molar.
Depth of intragingival extension about 1.0 to 1.5 mm below
mesial marginal ridge of molar.
After molar erupted, intragingival extension is removed.
Poor oral hygiene or lack of patient and parental
cooperation, medical conditions, such as blood dyscrasias,
immunosuppression, congenital heart defects, history of
rheumatic fever, diabetes, or generalized debilitation,
contraindicate.
REMOVABLE PARTIAL DENTURES
ACRYLIC PARTIAL DENTURE
Esthetic,
Function,
Speech and
Prevent tongue habits.
Cooperative and
Interest.
Unwise in uncontrolled caries,
Poor O.H.
PASSIVE LINGUAL ARCH
Multiple loss of primary teeth.
It does not satisfy requirements for
restoring function,
ADVANTAGES:
Eliminates problem of patient cooperation.
No problems with breakage or retention.
Need to be remade or altered.
Passive.
A W-shaped kind can be used in the
maxillary arch.
THANKS FOR YOUR
KIND
ATTENTION