Adriano G. Crismani

Transfer accuracy of two indirect bonding techniques—an in vitro study with 3D scanned models

Background and objectives Indirect bonding (IDB) proved to be an effective method for appropriate bracket positioning in patients. Different methods and materials are available for fabricating transfer trays. This in vitro study was designed to measure and compare the transfer accuracy of two common IDB methods. Materials and methods Sixty stone models were fabricated and separated in two groups of 30 models each (15 working models, 15 patient models). After placing brackets on the working models, 30 IDB trays were made: 15 silicone (method I) and 15 double-vacuum forms (method II). With these trays, the brackets were transferred to the patient models. The bracket positions were scanned before and after the IDB procedure with an intraoral scanner. The linear and angular discrepancies were then determined digitally by measuring six different dimensions: occluso-cervical, mesio-distal, bucco-lingual, tip, rotation, and torque. Results The silicone trays showed fewer transfer discrepancies, on average, in all measured dimensions. There were significant differences between the methods in the occluso-cervical (P < 0.001), mesio-distal (P = 0.001), and torque (P = 0.044) dimensions. With both methods, 100 per cent of the horizontal and transversal measurements of both methods were within the clinically acceptable range of 0.25 mm. With method I, 98.5 per cent of the vertical and 95.9 per cent of the angular measurements were within the range of 0.25 mm and 1°, respectively. With method II, 94 per cent of the vertical and 84.8 per cent of the angular measurements were within the clinically acceptable range. Conclusions Although both transfer methods showed a high precision, silicone trays scored better in terms of accuracy than double-vacuum forms.

Inter- and intraobserver variability in resonance frequency analysis of palatal implants--a technical note.

PURPOSE To assess inter- and intraobserver variability in wireless resonance frequency analysis (RFA) stability measurements of palatal implants and to evaluate the influence of age, sex, time after implant insertion, and measurement direction on variability. MATERIALS AND METHODS Three observers conducted wireless RFA stability measurements of palatal implants from 16 patients. Measurements were taken in anteroposterior and laterolateral directions and were repeated after 1 hour. RESULTS Data showed a small interobserver variation (1.93) with intraobserver variation (1.77) as its largest component. Time after implantation showed a strong influence (P = .027) on the interobserver variation. CONCLUSIONS The tested wireless RFA device can be considered a reliable instrument for measuring the stability of palatal implants. Multiple readings and observers could further improve measurement reliability.

Skeletal anchorage with microimplants (2007)

Author: A. Korrodi Ritto. Publisher: Facies—Centro de Estudos Harmonia Facial, Lda, Porto, Portugal Price: £96.00, €125 ISBN: 978-972-99576-3-5 Lack of co-operation and loss of anchorage are the main reasons why the use of skeletal devices has recently been introduced in orthodontics. In this comprehensive and useful manual, Dr Ritto has described, in an exhaustive and …