The authors necessitate careful handling of the dental roots and consider it necessary that indications for the use of pin constructions be widened; they suggest original modifications of such designs and analyze the results of treatment of 176 patients. Examinations of 2,664 adolescents have revealed various dentition defects in 23.2 +/- 1.5%, these defects leading to deformations. Orthodontic treatment and prostheses are necessary to prevent these deformations.