Clinical Treatment Experience Of Anterior Open Bite

Objective: The anterior open bite was one of the most common malocclusions in orthodontics.The incidence of the malocclusion was between 6.2%-50% around the world.This article was to collect and collate the cases of anterior open bite we received in recent years,and give a retrospective analysis about the formation mechanism,clinical manifestation,classification,clinical diagnosis and treatment of anterior open bite,in order to provide new ideas of the clinical treatment for the malocclusion.Methods: We Chose 15 anterior open bite patients who visited in Oral Hospital of Lanzhou University in recent years,screened 7 typical cases in this patients,summarized the etiology of the formation of this type of malocclusion,clinical diagnosis and therapeutic method of each patients.Combined literature,gave a retrospective summary.Results: Among the typical cases,2 cases were dental open bite,7 cases were skeletal open bite.There were 2 patient in the mixed dentition and 7 in the permanent teeth.Retrospect the medical history,we found that 4 patients had mouth breathing habits,5 patients had bad tongue habits,2 patient had family history,and 4 cases were associated with eruption of the third molar in adult patients.Through clinical manifestations,facial growth type,ODI,APDI,EI,and alveolar bone height analysis,2 patients were diagnosed dental open bite,7 patients were diagnosed skeletal open bite.However,most of the adult patients with skeletal open bite had the dental effect at the same time.For children who had anterior open bite in the deciduous and mixed dentition,the use of the vestibule shield,tongue spines and other treatments,combined with muscle function training could obtain a better therapeutic effect.For adult who had dental and mild skeletal anterior open bite,current treatment methods of MEAW,micro implant anchorage and extraction treatment produced a good effect took advantage of pendulum effe.Conclusion: Bad oral habits were the main causes of anterior open bite.In addition,the eruption of the third molar seemed to be the main cause of anterior open bite for adults.It should be attracted attention for orthodontic doctors.The increase of 1-NA(°),1-NA(mm),U1-PP(°)and ODI,vertical eruption insufficiency of anterior teeth were the standard for clinical diagnosis of dental open bite.The standard for clinical diagnosis of skeletal open bite were the following: decrease of ODI,increase of Mx-PABH and(or)Md-PABH,decrease of Mx-AABH and(or)Md-AABH.In addition,the increase of N-Me,ANS-Me,Ar-Go-Me,MP-FH,PP-MP,decrease of S-Go/N-Me and SN-PP,the ratio of N-ANS/ANS-Me less than 0.65 were references for the diagnosis of skeletal open bite.For anterior open bite patients in deciduous and mixed dentition,dental open bite was in the majority in this period,The reason was the imbalance of oral and external muscle caused by bad habits.Therefore,breaking the bad habits and training of muscle function were the key to the success of the clinical treatment.For adult dental and mild skeletal open bite,the treatment methods included MEAW,micro implant,zygomatic arch anchorage,micro splint and so on.At the same time,we should pay attention to the cause of deformity.Orthodontic and orthognathic treatment was the most effective treatment for good curative effect and facial type change for severe skeletal open bite.