الفهرس 
AcknowledgmentOnly 14 pages are availabe for public view
 |  | from | 124 |  |  |
| | | from | 124 | | |
Abstract
Background and aim:
The gummy smile caused by extruded maxillary incisors was successfully treated with their intrusion by miniscrews. In order to accelerate this treatment, a minimally invasive surgical technique called corticision was introduced. The aim of this clinical trial was to investigate the effect of corticision on the duration and rate of intrusion of maxillary incisors in patients with gummy smiles with deep bite.
Subjects and methods:
Fourteen Egyptian adult patients (twelve females and two males) with gummy smile and deep bite were divided into two equal groups; corticision with intrusion group and intrusion without corticision group. The inclusion criteria were class I or II malocclusion with deep overbite more than 3 mm and gummy smile more than 3 mm. The intrusion was done to all patients with two NiTi closed coil springs attached to the two miniscrews inserted between the roots of maxillary lateral incisors and canines and to the segmented wire from the two maxillary lateral incisors after leveling and alignment stage. The corticision technique was performed by a scalpel and mallet by making cortical incisions between the roots of the four maxillary incisors to a depth of 12 mm then removed by a swing motion devoloping a periodontal injury to the surronding tissue. Lateral cephalometric radiographs were taken at three stages; T0 (at the start of treatment), T1 (at the start of intrusion) and T2 (at the end of intrusion). Periodontal assessment and periapical radiographs (to evaluate root resorption) were taken at T1 and T2. The duration and rate of intrusion were compared between the two groups, as well as, periodontal and root resorption assessment.
Results:
There was no significant difference in the duration of intrusion between the corticision (4.1 months) and the control (4.5 months) groups. Also, There was no significant difference in the rate of intrsion between the corticision (0.68 mm/month) and the control (0.42 mm/month) groups. The periodontal condition of the intruded teeth was not changed after intrusion in both groups. Only irregular root contour was revealed after intrusion in both groups with insignificant difference between them.
Conclusions:
On the basis of the results obtained from the present study the following conclusions could be drawn:
1. The application of corticision during the intrusion of maxillary incisors, neither increased the rate of intrusion, nor decreased the duration of treatment.
2. There was no significant differences between corticision and non-corticision intrusion groups regarding the labial tipping of maxillary incisors, where It was increased in both groups following intrusion.
3. Most of the teeth in both intrusion groups manifested irregular root contour (score 1).
4. Nearly all the cases showed periodontal index of score 1, which was not statistically different between the two groups.