INCIPIENT MALOCCLUSION

BY: Dr. Richa Khanna

DEFINITION....An incipient malocclusion is defined as a

condition which shows a tendency to develop into a deviation from the normal

dentofacial or occlusal relationship

Types.... • DENTAL• SKELETAL• DENTO-SKELETAL

WHY DIAGNOSE WHILE INCIPIENT?? To prevent their establishment To refer at appropriate time. To minimize corrective treatment and its

duration.

DIAGNOSING INCIPIENT MALOCCLUSIONS

The modern concept is...... ........stressing

on prevention – oriented early

detection of problems

DIAGNOSING INCIPIENT MALOCCLUSIONS Incipient malocclusions are result of

developmental processes.....and not pathologic

Objective signs and symptoms measured by the dentist are morphologic characteristics of malocclusion and NOT physiologic measurements of function that help to treat any illness

DIAGNOSING INCIPIENT MALOCCLUSIONSALSO..... While diagnosing......Parents must be made to understand that

a normal occlusion may not develop always.....

AND.... How future problems could be

prevented and intercepted at INCIPIENT STAGE.

ESSENTIALS OF DIAGNOSIS

1. GENERAL EVALUATION:

Initial patient interaction Chief complaint- Find out what is important for the patient, that is the major concerns. Medical history Very important to elicit as orthodontic problems are mostly developmental Dental History- May additionally help to elicit parents attitude,

awareness and any hereditary component

Genetic history- any history of orthodontic

treatment in siblings, close relatives or parents themselves.

Sociobehavioural history Difficult to elicit Parents generally do not tell about

child’s emotional problems. You may ask about school progress

rather. Questions related to Quality of life

being affected may be put up.

ESSENTIALS OF DIAGNOSIS

It has three major areas:-the patient's motivation for treatment, -what he or she expects as a result of

treatment, and -how cooperative or uncooperative the patient

is likely to be.

AGE GENDER PRENATAL HISTORY Includes drugs, any illness, type of

delivery.

ESSENTIALS OF DIAGNOSIS

2. STRUCTURAL ASSESSMENT

EXTRAORAL:a. General i. Physical growth status: Ht&Wt To know present status and future potential. ii. Body typeb. Facial features i. Facial type ii. Shape of Head iii. Facial Profile iv. Lip posture v. Relative symmetry of facial structures.c. TMJd. Speech difficulties if any.

ESSENTIALS OF DIAGNOSIS

INTRAORAL EXAMINATIONS:

a. Jaw relationship( ant-post, vertical,lateral)

b. Open mouth examination: no. of teeth, any abnormality of size

and shape, restorations, oral hygiene, molar relation, overjet, overbite, midline.

c. Soft tissues: Gingiva, frenums,tongue, palate, tonsils,

oral mucosa in general,lips.

ESSENTIALS OF DIAGNOSIS

Tooth-Lip Relationships: Mini-Esthetics:

a. Tooth-Lip Relationships This includes: - Relationship of the dental midline of

each arch to the skeletal midline of that jaw (i.e., the lower incisor midline related to the midline of the mandible, and the upper incisor midline related to the midline of the maxilla

- vertical relationship of the teeth to the lips, at rest and on smile( incisor display)

ESSENTIALS OF DIAGNOSIS

b. Smile analysis:- Amount of Incisor and Gingival Display.- Smile arc , golden proportions etc.

ESSENTIALS OF DIAGNOSIS

3. FUNCTIONAL ASSESSMENT

RESPIRATIONTests for checking respiration mode are:a. Observation without informing the patientb. Observation while asking the patient to breathe.c. Mirror testd. Cotton/Butterfly teste. Water test

OCCLUSAL INTERFERENCE Such interferences may lead to deviated paths of

closure, and hence imbalance of musculature. May affect TMJ.

ESSENTIALS OF DIAGNOSIS

POTENTIAL PROBLEMS OF INCIPIENT MALOCCLUSION

I. PREDENTATE PERIODa. Type of delivery: Crossbite incidence is high in children born

with forceps delivery. Also, abnormal arch dimensions, increased

height of maxilla and increased length of mandible is seen

Narrow arches are more common.

b. Preterm birth: Gestational age less than 37 weeks Such children are under variety of metabolic

stresses.

Following problems in preterm infants may be index for developing probable malocclusion problems:

i. Palatal grooves and cleft formation ii. Primary incisor defects. iii. Delayed eruption of primary teeth

c. Neonatal jaw relationship: No precise relationship exists. Anterior openbite seen in gumpads is very

common...and is usually transient. Oral habits may influence duration of anterior

openbite.

d. Retained Infantile swallowing: In the infantile swallowing reflex tongue lies

between gumpads and, mandible is stabilised by

an obvious contraction of facial muscles. The buccinator is especially very strong

Infantile swallow disappears with eruption of primary incisors normally.

Sometimes, a transitional state between an infantile and mature swallowing can be seen with an open bite.

When infantile swallow persists even after eruption of permanent incisors, it leads to:

Very strong contraction of lips And Facial muscles, particulary

noticeable are buccinator contractions.

e. Inadequate breast feeding OR early weaning:

Lead to low impact muscle activity Problems in normal development of

alveolar ridges, palate. And, hence crossbites are frequent in

primary dentition. Early introduction of bottle may also

lead to such consequences.

II. DECIDUOUS DENTITION:

A. DENTAL ARCHES:

What to look for:

Spacing Crowding Isolated teeth crowding Relationship of crowding with any oral

habit

B. TRANSVERSE RELATIONSHIP:

What to look for: Midline discrepancies --- large midline shifts are usually rare in

primary dentition --- if present... Mandibular shift should be

suspected. It usually manifests as unilateral crossbite

--- True cause should be looked for - Whether developmental size discrepancy of jaws is present

Crossbite ---- Should be treated immediately

Overjet

C. Vertical Dimension:

What to look for: Openbite Deepbite

D. Eruption problems

What to look for:

Delayed eruption Missing tooth

E. Habits:What to look for: Associated features

F. Primary dentition terminus

What to look for: Second primary molar relationship

in non spaced dentition

Second primary molar relationship in non spaced mandibular and spaced maxillary dentition.

If present with a distal step

If present with a flush terminal relationship

Leads to development of disto-occlusion

immediately after eruption of

permanent first molars

Leads to development of

disto-occlusion if maxillary first

permanent molar erupts before mandibular

G. Impacted primary teeth: Very rare—usually due to

trauma...mostly re-erupt Can cause delay in eruption of

permanent teeth

H. Congenital absence of primary teeth

What to look for: Agenesis of permanent successors

I. Infected primary teeth: These may cause Ankylosis or

Enamel defects in permanent successors.

Infected teeth also may lead to single side chewing and hence, hygiene and malocclusion problems.

J. Retained primary teethWhat to look for: Lead to crossbites, ectopic

eruption, malocclusion.

K. Ankylosis of primary teeth:

Very common in primary molars Can delay eruption of permanent

teeth Inhibit growth of alveolar process,

leading to development of a bony step.

Supraeruption of opposite teeth can also occur

L. Loss of primary teeth: Can accelerate permanent

successor eruption if crown completion is complete and root formation has started.

Can delay permanent successor eruption if crown completion is not complete

M. Premature loss of primary teethLead to: Loss of arch length Tipping of adjacent teeth Supraeruption of opposing teeth

N. Supernumery teeth

M. Abnormal TMJ relationship -- Leads to development of

functional malocclusions

N. Gingival Or Periodontal conditions leading to premature loss of Primary teeth

SPACE LOSS & SPACE ANALYSIS

BY: Dr. Richa Khanna

RATE AND TIME OF SPACE LOSS Earlier the tooth is lost greater the initial

space loss

Studies have reported 1.5mm per year in the maxilla and 1 mm per year in mandible

Studies have also found that greatest space loss occurs in first four months.(Many controversial results are reported)

AMOUNT OF SPACE CLOSURE Studies have found the total space loss

upto 2.5 mm

DIRECTION OF SPACE CLOSURE Kronfeld’s theory states that there are

neutral areas located: between the bicuspids in maxilla and just mesial to the first molar in

mandible.

According to this theory : Teeth anterior to neutral zone have a

tendency to drift distally Teeth posterior to neutral zone have a

tendency to drift mesially

VARIABLES AFFECTING SPACE CONTROL INTERVENTIONS-- Given by Wright and Kennedy Oral musculature and habits Time elapsed since extraction Dental age, eruption pattern and bony

covering Available space Interdigitation Anamolies Sequence of eruption

SPACE DISCREPANCY ANALYSIS IN MIXED DENTITION

Two most imporatant variables considered for calculating space discrepancy in mixed dentition

Space requirement = Space needed for permanent canines + premolars (calculated from mixed dentition analysis, after taking into account

incisor position, curve of spee, late mesial shift. )

Space available = distance between mesial contact point of permanent molar and distal contact point of deciduous canine is done.

Space analysis is based on important assumptions:

(1) the anteroposterior position of theincisors is correct (i.e., the incisors are neither excessively protrusive nor retrusive),

(2) the space available will not change because of growth; and

(3) all the teeth are present and reasonably normal in size.

None of these assumptions can be taken for granted. All of them must be kept in mind when space analysis is done.

Besides these , curve of spee and late mesial shift should also be taken into consideration

Crowding and protrusion are really differentaspects of the same phenomenon.

If there is not enough room to properly align the teeth, the result can be

crowding, protrusion, or (most likely) some combination of the two.

For this reason, information about how much the incisors protrude must be available from clinical

examination to evaluate the results of space analysis.

This information comes from facial form analysis (or from cephalometric analysis if available).

The second assumption, that space available will not change during growth, is valid for most but not all children.

In a child with a well-proportioned face, there is little or no tendency for the dentition to be displaced relative to the jaw during growth, but the teeth often shift anteriorly or posteriorly in a child with a jaw discrepancy.

For this reason, space analysis is less accurate and less useful for children with skeletal problems (Class II, Class III, long face, short face

RADIOGRAPHIC METHOD It uses radiographic measurements for

prediction of sizes of unerupted permanent canines and premolars.

The technique can be used in maxillary and mandibular arches for all ethnic groups

Disadvantages:- This requires an undistorted

radiographic image- Even with individual radiographs, it is

often difficult to obtain an undistorted view of the canines, and this inevitably reduces the accuracy.

RADIOGRAPHIC METHOD

MOYER’S ANALYSIS It is a correlational-statistical method

Utilises the correlation between the size of the erupted permanent incisors and the unerupted canines and premolars

The size of the lower incisors correlates better with the size of the upper canines and premolars than does the size of the upper incisors, because upper lateral incisors are extremely variable teeth.

The data has been tabulated for white American children by Moyers

To utilize the Moyers prediction tables, mesiodistal width of the lower incisors is

measured this number is used to predict the size of

both the lower and upper unerupted canines and premolars.

No radiographs are required, and it can be used for the upper or lower arch.

Values at 75% Confidence Interval from the tables are found to be most accurate predictions.

MOYER’S ANALYSIS

Disadvantages:- tendency to overestimate- More accurate for Europeans from which

the data is derived

MOYER’S ANALYSIS

TANAKA AND JOHNSTON

It is a correlational-statistical method uses the width of the lower incisors to predict

the size of unerupted canines and premolars It requires neither radiographs nor reference

tables Very simple calculations

Disadvantages:

- the method has good accuracy in Europeans despite a small bias toward overestimating the unerupted tooth sizes.

- May not be accurate for all population groups

TANAKA AND JOHNSTON

HIXON AND OLDFATHER It is actually a combination of radiographic and

correlational-statsitical method

They found strongest correlation from:

SUM OF WIDTHS OF CENTRAL AND LATERAL INCISORS IN ONE QUADRANT

+ SUM OF WIDTHS OF TWO PREMOLARS OF SAME

QUADRANT AS MEASURED ON RADIOGRAPH

But these correlations were only for mandible From these predictions they devised a prediction

table

THANK YOU

QUES 1Which is the most easy and practical

Mixed dentition analysisa. Radiographic methodb. Moyer’sc. Tanaka – johnstond. Hixon-Oldfather

QUES 2Which Confidence interval of Moyer’s

prediction tables are used for accurate predictions?

a. 25th

b. 50th

c. 75th

d. 100th

QUES 3Neutral zone in the maxilla as given by

Kronfeld lies in:a. Incisor regionb. Canine refionc. Bicuspid regiond. Molar region

QUES 4Which of the following is an indication of

Incipient malocclusion in Primary dentition?

a. Absence of spacingb. Generalised spacingc. Leeway spacingd. Primate spacing

QUES 5Which is the most important factor that

needs consideration while calculating space discrepancy in a protruded well aligned mixed dentition?

a. Upper canine positionb. Lower molar position c. Lower incisor positiond. Upper premolar position

QUES 6Disadvantage of Radiographic method of

mixed dentition analysis:a. Distortion of radiographic imageb. Grayscale disturbances occurc. Cannot be used in both the archesd. Cannot be used in all ethnic groups

QUES 7Consequences of forceps delivery on the

developing jaws and occlusion can be:a. Openbite developmentb. Tongue thrust developmentc. Increase in facial heightd. Decrease in mandibular length

QUES 8Which of the following is considered to be

an Incipient malocclusion warranting treatment in future?

a. Adequate breast feedingb. Openbite in predentate periodc. Retained infantile swallowd. Spacing in primary dentition