Treatment of Long face / Open bite

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2 In the name of GOD

3 Treatment of Long face / Open bite in preadolescent children Presented by: Dr Somayeh Heidari Orthodontist

4 Reference: Contemporary Orthodontics Chapter 13 William R. Proffit, Henry W. Fields, David M.Sarver Mosby

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6 excessive growth of the maxilla in children with class II malocclusion has more of a vertical than an anteroposterior component if the maxilla moves downward, the mandible rotates downward and backward

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10 the ideal treatment for these patients would be to control all subsequent posterior vertical growth so that the mandible would rotate in an upward and forward direction this could be accomplished by controlling all tooth eruption if there were adequate mandibular vertical ramus growth

11 unfortunately, vertical facial growth continues through adolescence and into the post-adolescent years : active retention is likely to be necessary for a number of years

12 dramatic improvement can be demonstrated in selected patients: minor to moderate problems intervene in adolescence toward the end of the growth period retention would be critically important until vertical growth is completed, in the late teens or early 20s

13 There are several possible approaches to the long face pattern of growth in preadolescent children. In the order of their clinical effectiveness, they are: high-pull headgear to the molars high-pull headgear to a maxillary splint functional appliance with bite blocks high-pull headgear to a functional appliance with bite blocks

14 High-Pull Headgear to the Molars

15 to maintain the vertical position of the maxilla and inhibit eruption of the maxillary posterior teeth high-pull headgear to the posterior teeth: 14 hours a day greater than 12 ounces per side

16 does not control eruption of the lower molars, which can outstrip changes made by controlling the upper molar with the headgear

17 high-pull headgear to a maxillary splint

18 the use of a plastic occlusal splint to which the facebow is attached vertical force is directed against all the maxillary teeth, not just the molars have a substantial maxillary dental and skeletal effect with good vertical control

19 the appliance is must useful in a child with excessive vertical development of the entire maxillary arch and too much exposure of the maxillary incisors from beneath the lip (i.e., a long face child who does not have anterior open bite) to achieve both skeletal and dental correction, the patient must be compliant throughout what can be a very long treatment period

20 the maxillary splint allows mandibular posterior teeth to erupt freely if this occurs, there may be neither redirection of growth nor favorable upward and forward rotation of the mandible

21 Functional Appliance with Bite Blocks

22 a more effective alternative is the use of a functional appliance that includes posterior bite blocks the retraction force of the headgear is replaced by the somewhat lesser headgear effect of the functional appliance the primary purpose is to inhibit eruption of the posterior teeth and vertical descent of the maxilla

23 the appliance can be designed with or without positioning the mandible anteriorly, depending how much mandibular deficiency is present in the working bite, the bite must be opened past the normal resting vertical dimension if molar eruption is to be affected

24 in this position, the stretch of the soft tissue (including but not limited to the muscles) exerts a vertical intrusive force on the posterior teeth in children with anterior open bites, the anterior teeth are allowed to erupt, which reduces the open bite in the less common long-face problems without open bite, all teeth are held by the bite blocks

25 because there is no compensatory posterior eruption, all mandibular growth should be directed more anteriorly, at least to the extent that the overbite allows this type of treatment is effective in controlling maxillary vertical skeletal and dental growth This tends to project mandibular growth anteriorly and helps to close anterior open bites

26 because of the long period of continued vertical growth, if the functional appliance is used for the first phase of treatment, posterior bite blocks or other components (such as bone screws for skeletal anchorage) will be needed to control vertical growth and eruption during fixed appliance therapy and probably into retention

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28 high-pull headgear to a functional appliance with bite blocks

29 the most aggressive approach to maxillary vertical excess and class II jaw relationship is a combination of high-pull headgear and a functional appliance with posterior bite blocks +

30 extraoral force increases the control of maxillary growth high-pull headgear improves retention of the functional appliance produces a force direction near the estimated center of resistance of the maxilla functional appliance provides the possibility of enhancing mandibular growth controlling the eruption of the posterior and anterior teeth

31 in reality, the addition of headgear appears to provide little if any more vertical skeletal and dental control only a modest anteroposterior maxillary skeletal impact this benefit should be weighted against the effects of the simpler open bite functional appliance without headgear

32 a recent study: so little skeletal impact of the headgear-functional appliance no longer be recommended

33 Retention after anterior open bite correction

34 in patients who do not place some object between the front teeht, return of open bite is almost always the result of elongation of the posterior teeth, particularly the upper molars controlling eruption of the upper molars is the key to retention

35 the preferred method is an appliance with bite blocks between the posterior teeth that creates several millimeters of jaw separation this stretches the patient s soft tissue to provide a force opposing eruption

36 high pull headgear to the upper molars, in conjunction with a standard removable retainer to maintain tooth position, can be effective the intraoral appliance is beter tolerated and controls eruption of lower as well as upper posterior teeth excessive vertical growth and eruption of posterior teeth often continue until late in the teens or early twenties

37 a patient with a sever open bite problem: conventional maxillary and mandibular retainers for daytime wear an open bite bionator as a nighttime retainer

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