Department of Experimental and Clinical Medicine Faculty of Medicine, School of Dentistry, University of Foggia Director: Prof. Lorenzo Lo Muzio 26 Poster Number Graziano Montaruli, Gioacchino Pellegrino, Domenico Ciavarella Evaluation of dentoalveolar and skeletal effects in the transverse plane of the use of Nitanium Palatal Expander 2 in adults AIMS OF THE WORK The aim of this study was to evaluate dentoalveolar and skeletal effects that nickel-titanium palatal expander determines in the transverse plane, verifying its effectiveness in adult patients in permanent dentition in the treatment of unilateral or bilateral posterior cross-bite. MATERIALS AND METHODS 13 adult patients (8 females and 5 males, mean age 17,6) with unilateral or bilateral posterior cross-bite were treated with a nickel-titanium palatal expander NPE-2 (Nitanium® Palatal Expander 2™) at School of Dentistry, University of Foggia. The postero-anterior radiographic evaluation screening and analysis of casts at the beginning of treatment (T0) and at six months after the application of the device (T1) were performed to study the variations obtained with the NPE-2. RESULTS An increase of 2.9 mm (P<0,01) of the distance between the points CVM+d and CVM+s evaluated on the postero-anterior radiography and on casts 2.2 mm (P<0,01) of the posterior width, 1,4 mm (P<0,01) of the anterior width, 1,8 mm (P<0,05) of the canine distance, with a complete correction of unilateral or bilateral cross-bite, were obtained. No statistically significant increase in the transverse diameters was obtained in the lower arch. No evidence of radiographic radiolucency was detected in patients treated at the level of the median-palatal suture. T0 T1 D P Parameters Average St. dev St.dev T0-T1 1 6+6 44,6 1,94 46,8 1,67 2,2 ** 2 4+4 36,1 2,12 37,5 2,36 1,4 3 3+3 33,1 3,32 34,9 3,02 1,8 * 4 per.arc. 78,2 3,12 79,7 3,16 1,5 NSS 5 6-6 39,9 1,23 41,1 1,46 1,2 6 3-3 28,3 1,08 28,9 1,38 0,6 *P<0,05 **P<0,01 ***P<0,001 T0 T1 D P Parameters Average St. dev T0-T1 1 Mxd-Mxs 62,4 2,42 63,8 1,96 1,4 * 2 CVM+d – CVM+s 57,5 1,88 60,4 1,98 2,9 ** 3 OCCLd - OCCLs 48,2 2,02 50,6 2,46 2,4 4 CVM-d – CVM-s 56,8 57,4 2,68 0,6 NSS *P<0,05 **P<0,01 ***P<0,001 CONCLUSIONS Dentoalveolar changes induced by the application of NPE-2 and the correction of unilateral or bilateral cross-bite show the effectiveness of this device even in adult patients in the permanent dentition. References Arndt WV. Nickel titanium palatal expander. J Clin Orthod 1993;27:129-37. Corbett MC. Slow and continuous maxillary expansion, molar rotation and molar distalization. J Clin Orthod 1997;31:253-63. Marzban R, Nanda R. Slow maxillary expansion with nickel-titanium. J Clin orthod 1999;33:431-41. Anelli G, Montaruli G. Espansione del mascellare superiore mediante il NiTi palatal expander. Mondo Ortod 1999;1:65-72. Karaman AI. The effects of nitanium maxillary expander appliances on dentofacial structures. Angle Orthod 2002;72:344-54. Ferrario VF et Al. Quantitative effects of a nickel-titanium palatal expander on skeletal and dental structures in the primary and mixed dentition: a preliminary study. Eur J Orthod 2003;25:401-10.