Clinical Research Directory

Inclusion Criteria: * Clinical inclusion criteria: * Children requiring bilateral extraction of mandibular first primary molars or those with previously extracted molars no more than 6 months prior to intervention (11) . * Existence of teeth on the mesial and distal side of edentulous area. * Angle's Class I molar relationship and/or flush terminal/mesial step primary molar occlusion Radiographic inclusion criteria: * No periapical and/ or furcural pathological condition related to abutment teeth. * Presence of tooth germ of the succeeding tooth (mandibular first premolars). * Presence of more than 1 mm of bone overlying the successor tooth germ Exclusion Criteria: * Carious abutment teeth requiring pulp therapy. * Carious abutment primary teeth requiring a full coverage restoration. * Patients with history of bruxism or/and clenching. * Patients with medical, intellectual or physical disabilities. * Patients with abnormalities as posterior cross-bite, open bite, and deep bite