IDEAL MeansNORMAL?!

CLASS I MALOCCLUSION

Dr. Dana Al. SingeryB.D.S, M.Sc. (Orthodontics)

What’s Class I

according to

Angle ???

1- Normal class I occlusion2- In some subject *Crowding and irregularities of the teeth.* Discrepancy in the transverse relationship.* Increase overbite.* Anterior openbite.* Localized malpositions.* Spacing.

Etiology of class I malocclusion

1.Skeletal: but it can also be Class II or ClassIII with dental compensation.Milder transverse discrepancies, Increasedvertical skeletal proportions.

2.Soft tissue factors: In most is notan aetiological factor. The majorexception to this is bimaxillaryproclination,

3.Dental factors: the main aetiologicalinfluences. Environmental factors can alsocontribute to crowding or spacing. Local factors alsoinclude displaced or impacted teeth, and anomaliesin the size, number, and form of the teeth, all ofwhich can lead to a localized malocclusion.

Treatment of Class I malocclusion:

1.Crowding and irregularities of the teeth

• Tooth size-arch length discrepancy• Premature loss of deciduous teeth.• Prolonged retention of deciduous teeth.• Presence of supernumerary teeth.• Macrodontic teeth.• Altered path of eruption.

The position, presence, and prognosis The site and the degree The patient’s profile

UPPER LOWERLateral incisors labially or palatally linguallyCanines buccally or palatally buccally2nd premolars palatally lingually2nd ,3rd molars buccally mesioangular

or impaction

Spontaneous relief of crowding by extraction of the deciduous dentition After one year no improvement…require

active tooth movement with appliances.

2.Crossbite: of the buccal teeth which either unilateral or bilateral crossbite correct by expansion either removable appliance or fixed appliance.

3.Increased overbite (deepbite): Need correction if it is producing gingival trauma.Removable or Fixed appliance ??

4.Openbite: Requiring vertical movement (extrusion) of the incisor teeth or (intrusion) of posterior teeth which can be achieved only with the use of fixed appliance.

5.Spacing: Generalized spacing is rare. Orthodontic management of generalized spacing is frequently difficult. In milder cases it may be wiser to encourage the patient to accept the spacing, or if the teeth are narrower than average???Sever Hypodontia ?!

6.Median diastema: is a space between the central incisors, which is more common in the upper arch.Tend to reduce or close with the eruption of the caninesBefore: intervention is only necessary if the diastema is greater than 3 mm.

After: space closure is usually straight forward. Prolonged retentionIt may be better to accept a minimal diastema

??If the frenum is a contributory factor, then

frene-ctomy should be considered.

7.localized malposition: canines and 2nd

premolar Which are the most commonly affect teeth. Usually the last tooth that erupted in the segment are displaced. Such displacement can be treated by relief of crowding.

8.Bimaxillary proclination: the term used to describe occlusions where both the upper and lower incisors are proclined. Bimaxillaryproclination is seen more commonly in some racial groupsSo what’s the cause of increasing OVERJET ??

Management is difficult. Retroclination of the lower labial segment will encroach on tongue space.If the lips are incompetent, but have a good

muscle tone.

Where bimaxillary proclination is associated with competent lips, or with grossly incompetent lips

1.To improve esthetic of the patient.

2.To improve function of the teeth and jaw.

Post treatment retention:1.Severity of the case.2.Type of tooth movement.3.Type of treatment.