classII division 1 malocclusion

it is about class II div 1 with full information about diagnosis and treatment plan

1. BY:BATOOL MOHAMMED FARHAN CLASS II DIVISION 1

2. CONTENTS Definition Etiology Occlusal features Assessment of and treatment planning in Class II division 1 malocclusions Early treatment Management of an increased overjet associated with a Class I or mild Class II skeletal pattern Management of an increased overjet associated with a moderate to severe Class II skeletal pattern Retention

3. Definition is when the maxillary anterior teeth are proclined and a large overjet is present.

4. E tiology Skeletal pattern A Class II division 1 incisor relationship is usually associated with a Class II skeletal pattern, commonly due to a retrognathic mandible

5. Etiology Soft tissues the resting position of the patient's soft tissues and their functional activity also play a part. in one of the following ways circumoral muscular activity to achieve a lip-to-lip seal the mandible is postured forwards to allow the lips to meet at rest the lower lip is drawn up behind the upper lndsors the tongue is placed forwards between the incisors to contact the lower lip, often contributing to the development of an incomplete overbite: Acombination of these

6. Etiology Dental factors A Class II division 1 incisor relationship may occur in the presence of crowding or spacing. Where the arches are crowded, lack of space may result in the upper incisors being crowded out of the arch labially and thus to exacerbation of the overjet .

7. Etiology Habits A persistent digit-sucking habit will act like an orthodontic force upon the teeth if indulged in for more than a few hours per day. The severity of the effects produced will depend upon the duration and the intensity, but the following are commonly associated with a determined habit

8. Occlusal features The overjet is increased the upper incisors may be proclined or upright The overbite is often increased forward adaptive tongue position a habit, or increased vertical skeletal proportions. an anterior open bite preexisting gingivitis.

9. Assessment of and treatment planning in Class II division 1 malocclusions Factors influencing a definitive treatment plan The patient's age The difficulty of treatment The likely stability of overjet reduction The patient's facial appearance

10. Assessment of and treatment planning in Class II division 1 malocclusions Practical treatment planning The decision as to whether extractions are required will depend upon the presence of crowding the tooth movements planned their anchorage requirements Class Il division 1 malocclusions are commonly associated with increased overbite, which must be reduced before the overjet can be reduced . Overbite reduction requires space (about 1-2 mm for an averagely increased overbite )

11. Where the lower arch is well aligned and the molar relationship is Class II, space for overjet reduction can be gained by distal movement of the upper buccal segments or by extractions. a Class I buccal segment relationship is preferable. If extractions are carried out in the upper arch only, the molar relationship at the end of treatment will be Class II. This is functionally satisfactory, but as half a molar width is narrower than a premolar, some residual space often remains in the upper . arch. However with fixed appliances. the upper first molar can be rotated mesiopalataJJy to take up this space by virtue of its rhomboid shape. is usually considered if the molar relationship is half a unit Class II or less, a full unit of space can be gained in a co-operative, growing patient

12. appliances have been developed which aim to produce distal movement of the molars. These have been classified as follows: Inter-maxillary: anchorage derived from within the arch - anterior teeth, premolars, coverage of palatal vault. Intra-maxillary: anchorage derived from opposing arch. In Class II cases this is the lower arch. Absolute anchorage: anchorage derived from implants. Examples include microimplants and palatal implants.

13. Early treatment Preadolescent children were randomized to either observation or to early treatment with either a functional appliance or headgear . Following this phase, patients underwent comprehensive treatment with fixed appliances in the permanent dentition. The results indicated that the early skeletal effects are not maintained long-term. the time in fixed appliances was reduced for children who underwent early treatment the overall treatment time was considerably longer if the early treatment time was included

14. Early treatment At present many clinicians feel that treatment is best deferred until the eruption of the secondary dentition where space can be gained for relief of crowding and reduction of the overjet by the extraction of permanent teeth (if indicated), soft tissue maturity increases the likelihood of lip competence. In the interim a custom-made mouthguard can be worn for sports .

15. if the upper incisors are thought to be at particular risk of trauma during the mixed dentition, treatment with a functional appliance can be considered

16. Boy aged 9 years with a Class II division 1 malocclusion on a Class II skeletal pattern. As the upper incisors were at risk of trauma, treatment was started early with a functional appliance.

17. . Following eruption of the permanent dentition, definitive treatment involving the extraction of all four second premolars and the use of fixed appliances was carried out to correct the inter- incisal angle and alleviate thecrowding (note the retroclination of the upper incisors as most of the reduction of the overjet has been achieved by dentoalveolar change )

18. Management of an increased overjet associated with a Class I or mild Class II skeletal pattern Fixed appliances, with extractions if indicated, will give good results in skilled hands in this group In patients with moderately crowded arches. lower second premolars and upper first premolars are a common extraction pattern as this favours forward movement of the lower molar to aid correction of the molar relationship and retraction of the upper labial segment.

19. Class II division 1 malocclusion on a Class I skeletal pattern with crowding

20. A functional appliance can be used to reduce an overjet in a cooperative child with well-aligned arches a mild to moderate Class II skeletal pattern provided that treatment is timed for the pubertal growth spurt

21. In a limited number of cases with good arch alignment. no crowding and proclined upper incisors a removable appliance can be considered

22. Management of an increased overjet associated with a moderate to severe Class II skeletal pattern Management of the more severe case is the province of the experienced operator. There are three possible approaches to treatment Growth modification Orthodontic camouflage Surgical correction

23. Growth modification by attempting restraint of maxillary growth, by encouraging mandibular growth, or by a combination of the two

24. Orthodontic camouflage using fixed appliances to achieve bodily retraction of the upper incisors . The severity of the case that can be approached in this way is limited by the availability of cortical bone palatal to the upper incisors and by the patient's facial profile. If headgear is used in conjunction with this approach, a degree of growth modification may also be produced in favourably growing children.

25. Patient with Class II division 1 malocclusion on a moderately severe Class II skeletal pattern treated by orthodontic camouflage in which both upper first premolars were extracted to gain space for overjet reduction and fixed appliances were used for bodily retraction of the upper incisors

26. Surgical correction In cases with a severe Class II skeletal pattern, particularly where the I lower facial height is significantly increased or reduced, a combination of orthodontics and surgery may be required to produce an aesthetic and stable correction of the malocclusion The threshold for surgery is lower in adults because of a lack of growth.

27. Retention retention must be considered during treatment planning. Provided that the upper incisors have been retracted to a position of soft tissue balance and are controlled by the lower lip, the prognosis is good. To aid stability, full reduction of the overjet and the achievement of lip competence is advisable . If the overjet is not fully reduced there is the risk that the lower lip will continue to function behind the upper incisors, with a subsequent relapse in incisor position.