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Cephalometric analyses are useful for planning and provision of orthodontic treatment. A and B points are used to resemble the anterior part of maxilla and mandible and N represents the anterior part of the cranial base. The position of N may influence measurements of SNA, SNB, and ANB and changes of N in the antero-posterior plane are thought to have a larger influence on the above measurements than vertical ones. Several methods have been proposed to address this issue, such as the Wits appraisal, the ‘Individualized ANB’, and the ‘Eastman correction’; the latter is mainly used in the UK. This study used a geometrical model of a lateral cephalogram with standard Caucasian average values for SN length, position of A and B points for male and female patients. Linear and angular measurements were digitized using Dolphin™ Imaging software. N was moved in antero-posterior and vertical planes and subsequent changes of SNA, SNB, and ANB were measured and the Eastman correction applied. The correction overestimated the SNA and ANB values in the opposite direction to the directly measured SNA and ANB when N moved posteriorly towards S: The directly measured values tended to show a Class II relationship but the correction indicated a Class III skeletal base. As N moved anteriorly, the Eastman correction overestimated the measured Class III skeletal relationship; SNA did not fall below 81 for correction in the opposite direction. Vertical positional changes had little impact on the underlying ANB and correction was not indicated clinically. [ABSTRACT FROM PUBLISHER]

This study compared peak insertion torque values of six commercially available self-drilling mini-implants [Mini Spider® screw (1.5 × 8 mm), Infinitas® (1.5 × 9 mm), Vector TAS® (1.4 × 8 mm), Dual Top® (1.6 × 8 mm), Tomas Pin® (1.6 × 8 mm), and Ortho-Easy® (1.7 × 6, 8, and 10 mm)]. Twenty implants each were drilled into acrylic rods at a speed of 8 rpm using a motorized torque measurement stand, and the values were recorded in Newton centimetres (Ncm). A further 20 Ortho-Easy® implants with a length of 6 and 10 mm were tested at 8 rpm; 20 implants of 6 mm length were also tested at 4 rpm. Kaplan–Meier estimates of the peak torque values were compared using the log-rank test with multiple comparisons evaluated by Sidak’s test.There were significant differences in the maximum torque values for different mini-implants with the same length. The Mini Spider® screw and Infinitas® showed the lowest average torque values (6.5 and 12.4 Ncm) compared with Vector TAS®, Dual ToP®, Tomas Pin®, and Ortho-Easy® (30.9, 29.4, 25.4, and 24.8 Ncm, respectively). There was no correlation between the diameter of the implants and torque values. The Tomas Pin® showed the largest standard deviation (7.7 Ncm) and the Dual Top® implant the smallest (0.6 Ncm). Different insertion speeds did not result in significant differences in peak torque values but the 6 mm mini-implants showed significantly higher torque values than the 8 and 10 mm implants. Using a ‘torque limiting’ screwdriver or pre-drilling cortical bone to reduce insertion, torque appears justified for some of the tested implants. [ABSTRACT FROM PUBLISHER]

This study ascertained the influence of orthodontic appliances on subjective ratings for social competence (SC), intellectual ability (IA), psychological adjustment (PA), and attractiveness in young adult orthodontic patients.A cross-sectional analytical questionnaire study was conducted with 130 undergraduates from the UK. Each participant was asked to look at a single, randomly assigned colour photograph of a young adult female and then asked to make judgements concerning her personal characteristics. Five modified photographs of the same young adult female were used: (1) no appliance, (2) stainless steel fixed orthodontic appliance, (3) ceramic fixed orthodontic appliance, (4) gold fixed orthodontic appliance, and (5) clear colourless aligner. Likert scales with higher scores indicating more positive ratings were used. The results were analysed using chi-square test, one-way univariate analysis of variance, and post hoc Tukey-B and Kruskal–Wallis tests.The results showed that greater perceived IA was associated with the appearance of no appliance (mean values: 7.56) rather than steel (6.67) or ceramic appliances (6.65) but similar to the gold (7.35) and aligner (7.08) appliances. No significant differences between the different orthodontic appliance appearances were found for SC and PA. A trend existed where the no appliance image (resembling a lingual appliance) or clear aligner was considered more attractive than the visible buccal fixed appliances.In the absence of other information, the judgements an individual young adult makes concerning the personal characteristics of a young adult are influenced by dental appearance and orthodontic appliance design. This may influence orthodontic appliance choice. [ABSTRACT FROM PUBLISHER]

This three-part study investigated the reproducibility of natural head posture (NHP) using radiographs and photographs. In part 1, reproducibility of cephalograms 1 year after the introduction of NHP was investigated and found to be less favourable (Dahlberg coefficient of 2.99 degrees) than most other previous investigations. In order to minimize radiation exposure of patients, reproducibility of photographs and method agreement between photographs and cephalograms were investigated in part 2. Reproducibility of the two photographs was poor (2.71 degrees). However, method agreement between cephalograms and the photographs taken at the same time was good (1.39 degrees). Replacement of the radiographic method with the photographic method for assessing NHP reproducibility appeared justified. Changing the protocol for achieving NHP in part 3 of the study improved reproducibility substantially (1.41 degrees). Various statistical methods were used to assess reproducibility and method agreement. Bland and Altman's graphical representation was found to be the most appropriate for method agreement. The Dahlberg coefficient, commonly used to assess NHP repeatability/ reproducibility, does not provide an extreme enough interval to allow a sufficient clinical assessment of a method to be undertaken, compared with the reproducibility coefficient. That is, the latter provides a 95 per cent range, compared with 52 per cent with Dahlberg. [ABSTRACT FROM AUTHOR]

A response by C. Z. Y. Whang and colleagues to a letter to the editor about their article on orthodontic mini-implants.