1)Journal of periodontology July 2001 (Vol. 72, No. 7)
Orthodontic Tooth Movement Enhances Bone Healing of Surgical Bony Defects in Rats
Alexander D. Vardimon, Carlos E. Nemcovsky, and Eleni Dre
Abstract
Background: The question of whether the repair of an alveolar bony defect can be enhanced by orthodontic tooth movement was addressed.
Methods: Alveolar bone defects were created in 52 Wistar male rats anterior to both maxillary first molars. After 1 week of healing, orthodontic protraction was applied for 2 weeks on the right side, resulting in mesial tipping and displacement movement. Subsequently, a retention appliance was inserted for 1 week. The left side served as the untreated (control) group. Vital bone staining (procion brilliant red H-8) was administered before and after orthodontic traction. Histomorphometric analysis was performed on 62 hemimaxillae using UV confocal microscopy and an imaging program. The total area of the bony defect was divided into 4 equal quadrants, and the area of bony apposition in each quadrant was measured.
Results: The total area of bony apposition was 6.5-fold larger in the treated (26.41 ´ 104 ± 28.92 ´ 104 mm2) than in the control group (4.07 ´ 104 ± 2.82 ´ 104 mm2), approaching statistical significance (P = 0.065). The treated occlusal quadrants demonstrated highly significant (P = 0.010), greater bone apposition compared to the control group (13.8-fold) and to the treated apical quadrants (P = 0.04, 5-fold).
Conclusions: This study confirms that orthodontic tooth movement is a stimulating factor of bone apposition. A conversion in the repair pattern of the bony defect from apico-occlusal in the control group (no tooth movement) to occluso-apical in the treated group (with tooth movement) further supports the linkage between tooth movement and enhanced bone deposition. Clinical implication suggests incorporation of orthodontic tooth movement in regenerative therapy. J Periodontol 2001;72:858-864.
KEY WORDS
Animal studies; alveolar bone loss/therapy; tooth movement; orthodontics, corrective.
2)Journal of periodontology February 2000 (Vol. 71, No. 2)
Mucogingival Interceptive Surgery of Buccally-Erupted Premolars in Patients Scheduled for Orthodontic Treatment I. A 7-Year Longitudinal Study
Giovanpaolo Pini Prato,< Tiziano Baccetti, Cristina Magnani, Giancarlo Agudio,and Pierpaolo Cortellini
Abstract
Background: Mucogingival interceptive therapy in patients with buccally erupting teeth is performed to prevent the ectopic permanent tooth from developing periodontal lesions. The keratinized tissue entrapped between the erupting tooth and the deciduous tooth is retained to maintain a satisfactory width of the gingiva for the permanent tooth. The aim of the present study on buccally-erupted premolars scheduled for orthodontics was to evaluate the keratinized tissue width 3 months, 2 years, and 7 years subsequent to mucogingival interceptive therapy and orthodontic treatment.
Methods: Twenty-nine patients participated. Three different surgical techniques were used according to specific indications. Eight patients were treated with double pedicle flaps (DPF), 10 patients with apically positioned flaps (APF), and 11 with free gingival grafts (FGG).
Results: The amount of keratinized tissue on the treated (test) sites was not significantly less than on the control (untreated) sites showing normally erupting premolars at all observation periods. All 3 surgical procedures appeared to be effective in saving the keratinized tissue for the permanent tooth. Preoperative periodontal parameters such as gingival width, probing depth, and bleeding on probing significantly influenced the outcome 3 months after surgery (P <0.01).
Conclusions: Mucogingival interceptive surgery is an effective approach to conserve the keratinized buccal gingiva of ectopically erupting premolars. J Periodontol 2000;71:172-181.
KEY WORDS
Follow-up studies; gingiva/anatomy and histology; tooth extraction; tooth eruption, ectopic; orthodontics, interceptive; mucogingival surgery.