During orthodontic tooth movement (OTM) a remodeling of the periodontal ligament (PDL) and the alveolar bone occurs. We have recently observed that the expression of CGRP and substance P (SP) increases in the PDL and dental pulp in response to buccally directed OTM of the upper first molar in the rat. We have now examined whether there is also an involvement of VIP and NPY in this type of OTM. A sectional arch wire cemented to the upper incisors exerted an orthodontic force, mediated by a coil on the lingual side of the tooth, for 24 hours. It was observed that the blood vessels in the periodontal ligament were supplied with VIP- and NPY-immunoreactive (IR) nerve fibers, whereas VIP-IR nerve fibers in contrast to NPY-IR fibers were only occasionally observed in the dental pulp. No significant changes were observed in response to OTM. The observations suggest that VIP and NPY, in contrast to the main sensory neuropeptides CGRP and SP, are not involved in the tissue processes that occur in the remodeling of PDL and alveolar bone during orthodontic tooth movement.

Objective: The Psychosocial Impact of Dental Aesthetics Questionnaire (PIDAQ) is an instrument developed for assessment of orthodontic aspects of oral health-related quality of life (OHRQoL). This study aimed to translate and validate the Swedish version of PIDAQ for use in Swedish adolescents 12-19 years of age. Material and methods: The translation was made according to the process described in 'Guidelines for Establishing Cultural Equivalency of Instruments' by Ohrbach et al. Field testing was performed in a group of consecutive patients who were about to start orthodontic treatment (untreated group) and a group of consecutive patients who had recently finished orthodontic treatment (treated group). Results: During the translation procedure, a Swedish version of PIDAQ was formed. In the field testing, a total of 144 questionnaires, 72 from untreated patients (mean age 14.6 years) and 72 from treated patients (mean age 17.3 years) were collected. The exploratory factor analysis detected two factors, which differs from the factor structure in the original questionnaire. The mean total PIDAQ score was significantly higher (p < .001) in the untreated group, 40.6 (20.3), than in the treated group, 9.4 (10.5), implying a high discriminant validity. Reliability was excellent, with internal consistency Cronbach's alpha values varying from 0.94 to 0.97. Conclusion: The Swedish version of PIDAQ demonstrates good validity and excellent reliability and is suitable for future research on the effect of malocclusion on OHRQoL in Swedish 12-to 19-year-olds.

The study describes the distribution of mast cells and of substance P (SP) and calcitonin gene-related peptide (CGRP)-immunoreactive nerve fibers in the rat palatal mucosa, focusing on the anatomic relationship between these tissue elements. The maxilla of 10-14-wk-old rats was dissected free, fixed, demineralized and frozen. Consecutive sections were stained with avidin peroxidase or processed for immunohistochemistry. In order to define the correlation between nerve fibers and mast cells, double staining techniques were used. The distance between each avidin-positive mast cell and the nearest detectable nerve fiber was determined. 5-Hydroxytryptamine- (5-HT) and avidin peroxidase-positive mast cells were frequently seen in the palatal mucosa but were rarely found in the gingival area. A large number of nerve fibers showing SP- and CGRP-like immunoreactivity were seen, particularly in association with blood vessels. Some nerve fibers were located in contact with or very close to the mast cells but the vast majority of mast cells showed no close anatomic association to nerve fibers. The nerve fibers and mast cells were mainly concentrated to the same regions in the palatal mucosa where blood vessels occurred. The observations suggest that in the rat palatal mucosa the main functional relationship relates to SP/CGRP and the blood vessels, and only to a minor degree to SP/CGRP and mast cells.