Treatment of severe rotations of maxillary central incisors with whip appliance: Report of three cases
A 7-year-old boy was referred to the Pediatric Dentistry Department of Mashhad University of Medical Sciences with the chief complaint of severe rotation of one of his maxillary central incisor and a wound in the maxillary anterior labial mucosa caused by the continuous irritation of the incisal edge of rotated tooth. The medical history of the patient revealed no problems. In the extra oral examination, regarding lateral view, patient was mild convex and lip competent and in frontal view he was mesoprosopic. In the intraoral examination, there was Class I molar relationship with about 70° rotation of right maxillary central incisor []. Skeletal relationship of the patient was Class I and he did not have vertical problem. In the radiographic examination, pathologic problems such as supernumerary teeth or odontoma were not discovered, and revealed that 3/4 root was completed. After taking an alginate impression to fabricate study model, space analysis on study models did not show any space deficiency. The parents rejected any traumatic injury to the upper jaw in the past, but the history of intensive finger sucking habit was reported. At the first step, because of severe dental plaque accumulation due to inadequate oral hygiene, 1 week time was given to the patient to correct his oral hygiene. During this period, the parents were instructed to cover the incisal edge of rotated central incisor with wax to prevent continuous irritation of labial mucosa and to change it after each meal. In despite of the existence of dental caries in deciduous teeth of patient, the parents did not agree with restoring these teeth. After a week, an alginate impression was taken of the upper jaw in order to construct a removable appliance. This appliance was made of acrylic base plate, circumferential clasps on the maxillary primary canines and Adams clasp on the maxillary permanent first molars. In the later appointment, a mandibular first molar buccal tube (Dentarum, Germany) was bonded directly on the labial surface of the rotated central incisor with light cured composite resin (Trans Bond XT, 3M Unitek, USA). Whip spring was built with a segment of 0.4 mm stainless steel orthodontic wire (0.0016 inches) (Dentaurum, Germany), in which the distal end of the wire was bended to form vertical loop facing upward and immediately a vertical loop facing downward [Figures –]. The mesial end of the spring was inserted into the slot of the tube and to prevent damage to the gingival tissue, the outer end of the wire from the buccal tube was bent toward the incisal edge. The hook created in the distal end of the spring was engaged into the bridge portion of the right Adams clasp. The patient was instructed to remove the appliance only for tooth brushing after eating and in the rest of the time to wear the appliance for prevention of damage to gingival and buccal mucosa by the whip spring. After a few days, the patient returned with the complaint of a painful wound caused by whip spring in the mucobuccal fold area. Therefore, in order to deviate the wire from the vestibular mucosa, a vertical bend down and then a horizontal bend to distal was formed. The patient had no problem with the whip spring after this modification.\nAfter 4 weeks, the tooth was derotated very well. [] There was no need to coverthe incisal edge and the wound in labial mucosa completely healed. In every follow-up appointment, with a month interval, the whip spring was replaced by a new one. After 4 times replacement of the spring, rotation was almost corrected []. In order to overcorrect the rotated tooth, another removable appliance with a z-spring that forced the mesial aspect of lingual surface of the tooth was fabricated. At the end of treatment, supracrestal fiberotomy was performed and a segmented arch wire was placed to prevent relapse []. At 1 year follow-up, there were not any pathologic findings in the radiographic view like root resorption [].