The Etiology Of Open Gingival Embrasures Between The Two Mandibullary Central Incisors After Orthodontic Treatmeat In Adults

Objective:This study was to evaluate the etiology of posttreatmeat open gingival embrasures in adult orthodontic patients and to examine the associations of pretreatment mandibullary incisor malalignment,root angulation,crown shape,posttreatment alveolar bone height,interproximal contact position and root angulation.It provided a theoretical basis for clinical prevention of open gingival embrasures.Materials and Methods:A subsample of 179 patients was identified for measurement and divided into 2 groups:79 normal gingival embrasures and 100 open gingival embrasures,56 male and 123 female,18-38 years of age.Digital images of the pretreatment mandibullary models and posttreatment panoramic radiographs were made to measure the pretreatment and posttreatment variables.We used electronic vernier caliper to measure the pretreatment and posttreatment variables of the pretreatment mandibullary models and posttreatment panoramic radiographs,and remained 2 decimals in the actual data. The data was analyzed using SPSS 11.5 software package.Result:1,Pretreatment mandibullary central incisor rotation and overlap were not statistically associated with posttreatmeat open gingival embrasures.2,A posttreatment cementoenamel junction(CEJ)-interproximal contact distance greater than 6mm was associated with open gingival embrasures.3,A posttreatment CEJ-CEJ distance of the two mandibullary central incisors are correlated with open gingival embrasures after orthodontic therapy.4,The posttreatment alveolar crest-CEJ distance are associated with posttreatment open gingival embrasures.5,The posttreament long axis-interproximal contact distance are associated with open gingival embrasures formation.6,The incidence of female of open gingival embrasures is higher than male.7,The patients with dental calculus are more susceptible to open gingival embrasures.Conclutions:The investigation indicates that pretreatment local factors of dental and periodontal and posttreatment degrees of change of variables are significant factors in open gingival embrasures in the adult patients.Open gingival embrasures is a multi-factor in the pathogenesis of the disease.