11CH 27 MANAGEMENT OF THE DEVELOPING OCCLUSION (I)

DEVELOPMENT OF THE OCCLUSIONPREVENTIVE MANAGEMENT OF THE DEVELOPING OCCLUSION

McDonald, Avery, Dean. Dentistry For The Child And Adolescent, 8th Ed. Page: 625-683

Tuesday 17/2/1436 H9\12\2014

1:00 pm-2:00 pm

OTHMAN AL-AJLOUNI1

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

OBJECTIVESYou 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 OCCLUSIONPRIMARY MOLARS (Terminal Plane) RELATIONSHIPA. 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 PLANE3. DEEP BITE4. WIDE DENTAL ARCHES5. FLAT CURVE OF SPEE6. SHALLOW CUSPAL INTERDIGITATION7. VERTICAL PLACED INCISORS8. 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 ANALYSIS1. E/O and I/O photographs: an eight-film series of extraoral and

intraoral photographs2. Diagnostic dental casts: trimmed orthodontic study models3. I/O and panoramic radiographs: a full-mouth series or OPG4. Lateral and AP cephalograms: cephalometric analysis5. 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 ANALYSIS1. To determine need for space maintenance2. To determine need for minor tooth movement3. To aid in determining approach for minor tooth movement4. To evaluate need for guided eruption procedures5. To determine need for orthodontic referral:a. Comprehensive orthodontics b. Serial extraction

ARCH-LENGTH ANALYSIS1. 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. Arch Length2. Degree Of Crowding 3. Amount Of Space Needed 4. Size Of Unerupted Teeth 5. 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.

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THE BAND OR SSC AND LOOP MAINTAINER

Not restore chewing function and Not prevent eruption of opposing teethLoop 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 APPLIANCEAppliance 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 DENTURESACRYLIC 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