BY Dr Richa Khanna An incipient malocclusion is

BY: Dr. Richa Khanna

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

� To prevent their establishment � To refer at appropriate time. � To minimize corrective treatment and its duration.

The modern concept is. . . stressing on prevention – oriented early detection of problems

� 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

ALSO. . . 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.

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 historyany 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.

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.

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

� INTRAORAL EXAMINATIONS: 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. a.

� Tooth-Lip Relationships: Mini-Esthetics: 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) a.

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

3. FUNCTIONAL ASSESSMENT � RESPIRATION Tests for checking respiration mode are: a. Observation without informing the patient b. Observation while asking the patient to breathe. c. Mirror test d. Cotton/Butterfly test e. Water test � OCCLUSAL INTERFERENCE Such interferences may lead to deviated paths of closure, and hence imbalance of musculature. May affect TMJ.

I. a. � � � PREDENTATE PERIOD 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 Leads to development of disto-occlusion immediately after eruption of permanent first molars If present with a flush terminal relationship 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 teeth What 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 teeth Lead 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

BY: Dr. Richa Khanna

� Earlier the tooth is lost greater the initial space loss � Studies have reported 1. 5 mm 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)

� Studies 2. 5 mm have found the total space loss upto

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

-- 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

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 the incisors 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 different aspects 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

� 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.

� 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.

� Disadvantages: - tendency to overestimate More accurate for Europeans from which the data is derived

� 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

� 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

Which is the most easy and practical Mixed dentition analysis a. Radiographic method b. Moyer’s c. Tanaka – johnston d. Hixon-Oldfather

Which Confidence interval of Moyer’s prediction tables are used for accurate predictions? a. 25 th b. 50 th c. 75 th d. 100 th

Neutral zone in the maxilla as given by Kronfeld lies in: a. Incisor region b. Canine refion c. Bicuspid region d. Molar region

Which of the following is an indication of Incipient malocclusion in Primary dentition? a. Absence of spacing b. Generalised spacing c. Leeway spacing d. Primate spacing

Which is the most important factor that needs consideration while calculating space discrepancy in a protruded well aligned mixed dentition? a. Upper canine position b. Lower molar position c. Lower incisor position d. Upper premolar position

Disadvantage of Radiographic method of mixed dentition analysis: a. Distortion of radiographic image b. Grayscale disturbances occur c. Cannot be used in both the arches d. Cannot be used in all ethnic groups

Consequences of forceps delivery on the developing jaws and occlusion can be: a. Openbite development b. Tongue thrust development c. Increase in facial height d. Decrease in mandibular length

Which of the following is considered to be an Incipient malocclusion warranting treatment in future? a. Adequate breast feeding b. Openbite in predentate period c. Retained infantile swallow d. Spacing in primary dentition