Periodontal changes following molar intrusion with miniscrews.
BACKGROUND
With the introduction of skeletal anchorage system, recently it is possible to successfully intrude molar teeth. On the other hand, there have been concerns about periodontal changes associated with intrusion and there are few studies on this topic, especially for posterior teeth.


METHODS
Ten female patients were enrolled in this study. Maxillary molar intrusion was achieved by inserting two miniscrews and a 17 × 25 titanium molybdenum alloy spring. Crestal height changes were evaluated at three intervals including: Baseline (T0), end of active treatment (T1) and 6 months after retention (T2). Other variables including probing depth, gingival recession, attachment level and bleeding on probing were evaluated by clinical measurements in the three above mentioned intervals. One-sample Kolmogrov-Smirnov test ascertained the normality of the data. For all patients, the changes in tooth position and crestal height were evaluated using one-sample t-test. (P < 0.05).


RESULTS
Supra-erupted molars were successfully intruded a mean of 2.1 ± 0.9 mm during active treatment (T0-T1). A mean bone resorption of 0.9 ± 0.9 mm in mesial crest and 1 ± 0.8 mm in distal crest had occurred in total treatment (T0-T2). A mean of 0.6 ± 1.4 mm bone was deposited on mesial crest during the retention period (T1-T2) following tooth relapse. On average, 0.8 ± 0.4 mm attachment gain was obtained. Gingival margin coronalized a mean of 0.8 ± 0.6 mm throughout the entire treatment. Probing depth showed no significant change during treatment.


CONCLUSIONS
Within the limitations of this study, these results suggest that not only periodontal status was not negatively affected by intrusion, but also there were signs of periodontal improvement including attachment gain and shortening of clinical crown height.
Department of Orthodontics, Kerman Oral and Dental Diseases Research Center, Kerman University of Medical Sciences, Kerman, Iran.
Shahin
S
Bayani
Department of Orthodontics, Mashad Dental School and Dental Research Center, Mashad University of Medical Sciences, Mashad, Iran.
Farzin
F
Heravi
Department of Periodontics, Mashad Dental School and Dental Research Center, Mashad University of Medical Sciences, Mashad, Iran.
Mehrdad
M
Radvar
Department of Maxillofacial Radiology, Mashad Dental School and Dental Research Center, Mashad University of Medical Sciences, Mashad, Iran.
Najmeh
N
Anbiaee
Department of Prosthodontics, Mashad Dental School and Dental Research Center, Mashad University of Medical Sciences, Mashad, Iran.
Azam Sadat
AS
Madani
Molar; periodontal changes; tooth intrusion