Anzeige
Anzeige

Más contenido relacionado

Anzeige

Último(20)

eedce345.pptx

  1. Restoration of carious teeth to their correct antero posterior dimensions is absolutely essential especially proximal carious lesions on deciduous molars. The sole purpose is that permanent first molars should occupy the space distal to 2nd deciduous molars and should not prematurely migrate forward. 6 E
  2.  mkjgydfgubghip9 nh Iftfghiohiy tuighbijluc di67fghni Oivc6 fghiohbv o87by9uijh bvo8gi ry6ds67thy  867dv56tgiuohg8uo7tyuijol Jgffvrgihguo Moyers et al6 (1980) have identified six horizontal types of class II pattern which they designated: A, B,C, D, E and F.They identified five (1, 2, 3, 4, 5) vertical class II types ..
  3. • The mandible grows at a lesser pace than children with normal occlusion. • A more backward and downward inclination of the mandibular body leading to a lesser decrease in the facial angle is seen .
  4. is reduced while sagittal position of the mandible improves, which is measured as a reduction in angleANB. The improvement in craniofacial skeletal and dental profile is sustained during the period of fixed appliance therapy and post retention period.
  5. Occlusal and craniofacial characteristics from deciduous to mixed dentition • Distal terminal plane of second deciduous molars . Large over jet and overbite . • Narrow maxillary basal bone • Poor or no spacing in the deciduous dentition • Transverse discrepancy ( TD) between maxillary and mandibular deciduous intermolar withs (2.8-1.1) mm compared to nil among normal occlusal groups . • Retruded mandible and shorter mandibular length ( Co-Pg) on cephalometric examination • The maxilla can also displaced forward in class || subjects with or without difference in the mandible ..
  6. downward tipping of palatal plane at the anterior nasal spine (ANS). causes rotation of the palatal plane and slight increase in SN-PP angle. The inferior descent or extrusion of upper molars is essentially prevented by the forces of occlusion from the masticatory muscles.
  7. Interception of developing class II malocclusion Orthodontic interventions in class II malocclusion during deciduous dentition : Only limited orthodontic interventions are possible during the deciduous dentition stage for the interception of developing class II malocclusion…..
  8. Aforce 350 gm is used from cervical gear to the outer bow. The cervical headgear is recommended to be worn 12-14 hrs/day, in the evening and at night It usually takes about 12 months to achieve class I molar relation. improvement in over jet. This phase of orthopaedic correction is followed by full bonded fixed mechanotherapy
  9. Cases involving essentially maxillary excess compared to the mandible. Involve guiding alveolar growth in class II division 1 using headgear orthopaedic force. Used in class 2 with open bite cases to intrude molars Used in class 2 with deep bite cases to extrude molars
  10. The etiology may be attributed to mouth breathing/prolonged thumb sucking which can be elicited on carefully recording the history of the patient…. THUMP SUCKING MOUTH BREATHING
  11. Orthodontic interventions in class II malocclusion during mixed dentition.. 1- Cases involving essentially maxillary excess compared to the mandible. 2 - Cases involving essentially mandibular retrusion .
  12. Prevalence of class || malocclusion..
  13. For type B and E, extraoral traction to maxilla is suggested while for C, D and F functional jaw orthopaedics is proposed….
  14. • In general , the occlusal and skeletal features of class || malocclusion may remain stable or worsen to the stage of mixed dentition . There are certainly no favourable changes into a class | occlusion ..
  15. Kloehn (1953) was the earliest advocate of the use of orthopaedic forces to change positions of teeth and so influence the changes of the alveolar process in the maxilla. During normal craniofacial and alveolar growth, alveolus and teeth move forward and this can be intercepted. Thus if the maxilla is restrained in class II patients, mandible will follow its normal growth and reach to a normal relation with the maxilla.
  16. their extrusion The inner bow is expanded, 8 to 10 mm larger than distance between first molar tubes, and made parallel to the occlusal plane. The ends of inner bows are bent inwards to prevent the rotation of the first molars in their position.
  17. Age of treatment Kloehn facebow can be used in suitable cases where maxillary prognathism exists or mesial molar movement has occurred. The facebow is indicated in early mixed dentition when permanent maxillary first molars have erupted and can be banded.
  18. cervical traction is continued during/or till the end of activeclinical crown height. The purpose is to place it close to centre of resistance of the first molar which is near the trifurcation of the roots. The inner bow has stops against molar tubes and are so adjusted that a space of 4-6 mm is kept between the bow and incisors. The stops can be either soldered or bent..
  19. The outer face bow is extended to the tragus of the ear. The rigid outer bow is maintained at an elevation of about treatment to prevent relapse and enhance anchorage for maxillary anterior retraction/overjet correction
  20. Adverse effects Unwanted side effects of Kloehn headgear can result from the use of this method of treatment in high angle cases, where molar extrusion and distal tipping may be significant. This coupled with unfavourable growth of mandible and clockwise rotation may bring about an undesirable outcome. The success of the treatment is fully compliance dependent. The appliance, if not worn correctly or in case of loose molar band, breakage or welding failure of buccal tube(s), may cause injury of various kinds and severity.
  21. Long-term effects The long-term effects of early headgear treatment on 8-year follow-up have shown that headgear treatment shows a significant reduction in number of extraction treatment as compared to controls. The appliance inhibits the growth of the maxilla and results in wider and longer arches. Its main effect on maxilla is on the orientation of the maxillary plane. The maxillary arch expansion achieved during early headgear treatment results in a corresponding wide lower arch as an adaptation to maxillary arch.. The arch expansion has been found to be maintained during long-term follow-up
  22. Summary The forward growing maxilla can be intercepted during mixed dentition utilising orthopaedic forces in right direction and amount with Kloehn face bow This modality of treatment was once very popular especially in USA. The appliance is effective however requires patient compliance..
  23. Supervisor . Dr Maher Fouda Prepared by Hawwa Shoaib Class II division 1 malocclusion: features and early intervention of growing maxillary excess
  24.  Prevalence of malocclusion of class 2 malocclusion. Cephalometric finding. Clinical findings. Interception of growing class2 division 1 malocclusion. OVERVIEW
  25. Class 2 malocclusion comprises agroup of specific skeletal. Dental and facial features. It is second in frequency. Distribution and prevalence amongAngle’s malocclusion classes . It is the most frequently encountered and treated malocclusion in orthodontic practice
  26. Class 2 malocclusion is a synonym with distal position of the lower molar or mandible or protrusion of the maxilla and maxillary teeth or a variable combination
  27. Prevalence The prevalence of Angle’s class 2 malocclusion varies among population groups.. It is high among caucasians and lowest among the primitive races.. Class 2 malocclusions are observed in a wide – spectrum of presentation and severity …
  28. Clinical findings Presentation during deciduous and early mixed dentition.. • Adistal step relationship 2nd deciduous molars is an indication of a devoloping class 2 malocclusion during the mixed dentition .. Mixed dentition Permanent dentition
  29. Occlusal and craniofacial characteristics from deciduous to mixed dentition • It has been stated by Bishara et al that a distal step deciduous molar relationship is never self - correcting in growing children. • Children with straight terminal plane may develop into a class | molar or class || molar relationship influenced by the mandibular growth pattern and adjustment of occlusion during the late mixed dentition .that would in clinical sense . • Infer that when we encounter a class|| distal molar relation early in the mixed or permanent dentition. • Some sort of interceptive measures may have to be undertaken or planned because nature would not take care
  30. Occlusal and craniofacial findings of class II malocclusion during late mixed/permanent dentition stage • A child with class II malocclusion presents with a protrusive mid-face and/or a retrusive chin. They often report with complaints of superior protrusion, front teeth jutting out or showing too much. . Mid – face protrusive Retrusive chin
  31. This is often accompanied by a large overjet, deep bite (open bite can be seen in some) and a class II (distal) molar, premolar and canine relationship. . Large over jet Deep bite
  32. These children have an aberrant pattern of muscle activity of the facial musculature such as a flaccid upper lip hyperactive mentalis and lower lip trap under the procumbent upper incisors. Lower lip trap under the procumbent upper incisors
  33. The underlying craniofacial pattern of class II children has been extensively investigated. Most of the studies have concentrated on angular, sagittal and vertical measurements on lateral cephalograms. A few studies are also available ontransverse dimensions using PA cephalograms. Cephalometric findings PA. CEPHALOGRAM LA T. CEPHALOGRAM
  34. Aclass II skeletal pattern may be associated with: prognathic maxilla retrognathic mandible or combination of these in varying severity… Prognathic maxilla Rertognathic mandible
  35. McNamara5 observed two types of skeletal combinationsin class II children. He found mandibular retrusion thesingle most characteristic feature which was attributed toenvironmental factors such as : abnormal muscle function which altered occlusal interdigitations.
  36. The skeletal maxillary protrusion was not the major finding. But was rather neutral. The 2nd was a combination of maxillary and mandibular skeletal retrusion, often in association with altered mode of respiration, i.e. mouth breathing. These children with maxillary and mandibular retrusion showed : Greater vertical development of the face
  37. An excessive labial proclination and forward position of the maxillary anterior teeth is a common finding in class IIdivision 1 malocclusion. The maxillary first molar is more mesially positioned .. Class 2 division 1 , division 2 : the upper first molar mesially positioned.
  38. The anterior segment of maxilla is more protrusive and superiorly positioned. Excessive anterior cranial base length and enlarged frontal and maxillary sinus may be a contributing factor in the development of class IIdiv. 1 malocclusion. The mandible and dentition were identical to those of the controls in size, form and position..
  39. Maintenance of healthy primary dentition. All efforts are directed towards maintenance of the healthy primary dentition and thus integrity of arch length. This is achieved through education and home care by all the measures that minimize occurrence of dental caries. .
  40. Habits. Non-nutritive sucking habits such as prolonged thumb and finger sucking are taken care of with appropriate counselling and interceptive habit breaking appliance.A child with recurrent throat infection, nasal blockages or allergies should have ENT consultation to prevent mouth breathing. Mouth breathing ENT consultation
  41. Acervical headgear with a face bow is used to restrain maxillary growth and distalize the upper dentition to class I dentition.
  42. Components of a face bow Kloehn cervical facebow consists of an inner bow of 0.045" diameter and an outer bow of 0.071" diameter. The inner bow fits in the round headgear tube on the first molar bands. Conventionally, a double buccal tube is welded and soldered on to the maxillary first molar bands.. The inner face bow fits in the headgear tube on first molar bands Inner and outer facebow
  43. Filho et al8 recommended the onset of treatment in the late mixed dentition or beginning of the permanent dentition based on the belief that it often coincides with the facial growth spurt. It may also have the advantage of continuing the treatment with full-banded fixed appliance, following completion of 12 months of the first phase.
  44. Effect o f cervical headgear on dental/ craniofacial structures in sagittal, vertical and transverse dimensions.. Following 12-18 months of treatment, there is a reduction in maxillary protrusion, while mandible continues to Grow normally. The distalizing effect on maxillary molars causes them to erupt backward and downward, thus inhibit loweringof the posterior region of the maxilla, while anterior region continues to move downward. .
Anzeige