management of anterior open bite

1. 1 Management of anterior Management of anterior open bite cases open bite cases Prepared by: Prepared by: Dr Mohammed Alruby Dr Mohammed Alruby هلجا نم بعتا ائيش تدرا اذاو هيلع ظفاحف ائيش تببحا اذا M Management anagement of anterior open bite of anterior open bite Dr. Mohammed Alruby Dr. Mohammed Alruby

2. 2 Definition: failure of teeth to meet its antagonist in opposing arch while other teeth are in occlusion = Determination of causative factors is the most important step = Anterior open bite rarely seen as a separate entity I- Case history It should include the following: 1-Current age: Dental open bite is often seen in younger children (late deciduous and early mixed dentition), while in adolescent usually expect skeletal background 2-Family history: The presence of anterior open bite in other member of the family may be an indication of predetermined morphogenetic pattern which often manifest itself in skeletal open bite. 3-Systemic disease: Hormonal: hypothyroidism, rickets, acromegaly, amyloidosis, are associated with large size tongue that lead to skeletal open bite Mental retardation: such as mongolism ------ skeletal open bite Nasopharyngeal obstruction: such as tonsils, adenoid, nasopharyngeal allergy ----- mouth breathing ----- open bite skeletal 4-Physical or surgical trauma: Effect condylar growth center -------- mandibular hyperplasia which may associated with skeletal open bite 5-Abnormal pressure habits: Thumb sucking. Lip sucking, lip biting, tongue trust, or putting something between teeth of such condition are given up by the age of 5 to 6 years ------- dental open bite – if persist ------- skeletal open bite 6-Functional problems: mastication, swallowing, speech, expression 7-Previous orthodontic treatment: iatrogenic open bite II- Clinical examination a-Extra-oral: 1-Dental open bite: patient with dental open bite often have normal facial proportion 2-Skeletal open bite: patient with skeletal open bite often show the following: -Narrow and long face -Slim nose with narrow nasal slits -Incompetent lips, short upper lip and hyperactive lower lip -Shallow labio-mental sulcus -Excessive upper incisors show, and gummy smile -Increase lower third of the face -Receded chin point -Increase inter-labial gap -Steep mandibular plane -Excessive anti-gonial notch -Short ramus b-Intra-oral examination: 1-Dental open bite: may be associated with: M Management anagement of anterior open bite of anterior open bite Dr. Mohammed Alruby Dr. Mohammed Alruby

3. 3 = proclination of upper and lower incisors and open bite not more than 1mm ------ pseudo open bite = localized open bite confined to one or two teeth ------ mechanical interference by nail biting or putting something between the teeth, lead to attrition at incisal edge = well circumscribed open bite confined to the anterior region associate with history of thumb sucking -------- adaptive tongue thrust = clinical crown of anterior teeth is short 2-Skeletal open bite: May be associated with the following: -Will circumscribed open bite extending to the 1st molars -Ill-defined open bite extending to the last occluding molars - Poor inter-cuspation -Collapsed maxilla and buccal cross bite -Anterior teeth may be extruded -The posterior dentoalveolar segment is over-developed III- Study cast 1-Anterior posterior relationship: = anterior open bite rarely presented as a separate or isolated entity but may be associated with class I, II, III relationship = the upper incisors are proclined, while the lower incisors often retroclined by the action of lower lip = crowding is common finding in lower incisors, while the upper incisors may or may not show crowding = as a general, dental open bite is frequently associated with Class I skeletal base and good intercuspation while skeletal open bite may be associated of skeletal anterior posterior dysplasia and poor intercuspation. 2-Vertical analysis: = in dental open bite, the clinical crown of the anterior teeth is short, the anterior teeth lack vertical development due to mechanical interference or disturbance in eruption = the vertical height of posterior teeth is normal = in skeletal open bite: the anterior teeth may be extruded and there is excessive posterior dental alveolar development. The curve of spee is reversed 3-Transverse analysis: Dental open bite has no discrepancy in lateral direction while skeletal open bite may be associated with collapsed maxilla and buccal cross bite IV- Cephalometric analysis 1-Anterior posterior: Dental open bite is most frequently associated with skeletal class I while skeletal open bite is most commonly associated with skeletal class II or class III skeletal pattern 2-Vertical cephalometric analysis: The vertical facial measurements in skeletal open bite are more or less normal, while the skeletal open bite may show the following criteria:(Shudy 1964) -Excessive structural lowering of maxilla -Obtuse cranial base angle -Decrease PFH / AFH ratio M Management anagement of anterior open bite of anterior open bite Dr. Mohammed Alruby Dr. Mohammed Alruby

4. 4 -Short ramus *** Sassoni presented the following criteria: -The four planes of the face are convergent to meet the center O point just behind the back of the head ------- deep bite -Steep mandibular plane angle ----- open bite -Large gonial angle ------- open bite -Increase AFH particularly ALFH ------- open bite -Increase Y axis angle including vertical growth -Increase FMA angle -Increase posterior vertical dento-alveolar height -Acute inter-incisal and inter-molar angles -Accentuated anti-gonial notch -Narrow and long symphysis -The anterior nasal spin may be tipped upward V- Functional analysis 1-Upper lip: short and hypotonic 2-Lower lip; hyperactive 3-Tongue: tongue thrust is common = in dental open bite is usually simple adaptive and secondary to sucking habit, while skeletal open bite, tongue thrust is usually complex and secondary to painful pharyngeal lymphoid tissue enlargement. = although in primary infantile tongue thrust is rare condition but when occurs it can produce skeletal open bite. = skeletal open bite is also associated with large size of the tongue and abnormal tongue posture which may be secondary to some systemic disease and congenital syndrome 4-Cheek: the cheek musculatures are often involved in the activity of abnormal swallowing, so contraction of the lips and cheek musculature is seen in anterior open bite cases. This clearer in teeth a part swallowing 5-Muscles of mastication: In skeletal open bite, the muscles of mastication are hypoactive while the suprahyoid group of muscles are hyperactive 6-Free-way space: is reduced in skeletal open bite, due to dental compensation Etiology 1-Genetic factors: Postures, morphology of tongue Skeletal growth pattern of jaws especially mandible Vertical relationship of jaws bases 2-Environmental: = Habits: 91% of Rackosi study: thumb sucking, tongue thrust Nasopharyngeal air way obstruction: ------- mouth breathing -------- lower positioned of tongue - ----- posterior cross bite + anterior open bite = mesial axial inclination of both anterior and posterior teeth that may be due to: -Genetically tooth form and path of eruption M Management anagement of anterior open bite of anterior open bite Dr. Mohammed Alruby Dr. Mohammed Alruby

5. 5 -Altered inclination due to local factors -Strong anterior component force -Crowding 3-Problem related to failure of eruption: -Ankylosis of primary teeth -Failure of eruptive mechanism (primary failure) -Secondary failure due to cyst -Ankylosed permanent teeth: do not respond to orthodontic treatment N: B: Dockrell 1951: defined etiology as simplest form; a cause act at certain time on a certain tissue to produce a result Open bite: according to Graber: descriptive of a condition where space exist between the occlusal or incisal surface of maxillary and mandibular teeth in buccal or anterior segment where mandible brought into centric occlusion ** air way obstruction: Patients with skeletal long face are suspected to airway to airway obstruction, this face characterized as adenoid syndrome Narrow cheek Narrow nostril Lips are separated Exaggerated shadow below the eyes Treatment of open bite 1-Habit therapy: The first line to treatment of open bite cases is to stop habit by: -Habits a warns -Reward or punishment - Positive reinforcement -Habit breaking appliance -Early treatment is more preferred than later treatment 2-Appliance therapy: Using bite blocks to prevent eruption of teeth and permit eruption of others, the blocks with the action of muscles place intrusive effect on posterior teeth Treatment of open bite depend on localization and etiology of malocclusion and age of patient Open bite in deciduous dentition: Control of abnormal habits and elimination of dysfunction is important as: Thumb sucking, tongue thrust, mouth breather -------- tongue crib Long face syndrome ----- use of chin cup to redirect the growth Open bite in mixed dentition: 1-Dento-alveolar type: In early mixed dentition: use of tongue crib or oral screen to stop the habits In late mixed: appliance for stop the habit is not completely successful, so use multi-bracket appliance with long time retention M Management anagement of anterior open bite of anterior open bite Dr. Mohammed Alruby Dr. Mohammed Alruby

6. 6 2-Skeletal type: The treatment depends on: the severity of malocclusion, possibilities of dento-alveolar compensation In moderate cases: functional appliances with extra-oral force and extraction of teeth can solved all problems. In severe cases: some cases extraction of four premolars is benefits but other cases need orthognathic surgery with impactions of buccal segment to correct the bite N: B: in some cases of extreme vertical growth pattern, the lip seal is described so to allow better neuro-muscular environment, surgical correction of mentalis muscle is done to produce This operation is indicated in mixed dentition period after the eruption of lower canine teeth This type of transposition of the mentalis muscle attachment, permitting greater extension of lower lip to affect lip seal, can enhance the stability of the treatment result and bite closure 3-Combined type: Treat the perioral abnormal function of muscle Improved the skeletal relationship N: B:functional appliances as Frankel appliance or active vertical corrector that allow intrude of posterior teeth for both maxilla or mandible also can used for correction of anterior open bite. Open bite in permanent dentition 1-Multi-bracket fixed appliance with extraction therapy to correct the dento-alveolar problems and compensate skeletal problems In cases of steep MPA and palatal plane the molars teeth are tipped mesially so If 8 is well developed -------- extraction of 7 and upright 6 If 8 is not developed --------- extraction of 8 and upright 7 and 6 2-Use of magnets: repelling type of magnets: Dellinger 1985 3-Use of MEAW (Multiloop edgewise arch wire technique) to correct anterior open bite: Kin 1987, 4-by suing vertical elastics and extrusion of anterior teeth which is the common method used 5-extrusion arch: which is effective tools to correct upper and lower occlusal plane that diverge anterior to 1st molars 6-implant: some cases are ideally to close the bite by intruding the posterior teeth through implant that allow pure intrusive force titanium mini-plates in the buccal cortical bone in the apical region of 1st and 2nd molars produce 3 to 5mm molars intrusion 7-passive posterior bite blocks; passive functional appliance 3 to 4mm beyond the rest position that inhibit the increase in height of buccal dento-alveolar process thus prevent down and back rotation of mandible 8-glossectomy: in case of abnormal large tongue size that cause open bite anteriorly, which is common in European than US and Japanese, improve the prognosis and stability orthognathic treatment of open bite cases skeletal open bite is usually having excessive facial height with vertical excess, the surgical approach is by maxillary intrusion and mandible respond by rotate upward and forward to reduce the mandibular plane angle in cases of abnormal long distance from incisal edge to the base of chin can be corrected by: M Management anagement of anterior open bite of anterior open bite Dr. Mohammed Alruby Dr. Mohammed Alruby

7. 7 1-orthodontic intrusion of incisors 2-anterior segmental surgery 3-genioplasty to reduce the vertical height of chin Retention == in deciduous and mixed dentition, functional appliance is used and helpful, posterior teeth loaded with acrylic to prevent over-eruption == in permanent dentition: Hawley retainer is used with inter-occlusal cover of posterior teeth to prevent relapse by over eruption in buccal segment == some authors advice to use bonded lingual retainer in lower segment M Management anagement of anterior open bite of anterior open bite Dr. Mohammed Alruby Dr. Mohammed Alruby