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The aim of this study was to determine the validity of cervical vertebrae radiographic assessment to predict skeletal maturation. Left hand-wrist and lateral cephalometric radiographs of 958 Spanish children from 5 to 18 years of age were measured. On the left hand-wrist radiographs the classification of Grave and Brown was used to assess skeletal maturation. Cervical vertebrae maturation was evaluated with lateral cephalometric radiographs using the stages described by Lamparski and by Hassel and Farman. A new method to evaluate the cervical maturation by studying the changes in the concavity of the lower border, height, and shape of the vertebral body was created. Correlation coefficients were calculated to establish the relationship between skeletal maturation values obtained by the three classifications of vertebral and skeletal maturation measured at the wrist. All correlation values obtained were statistically significant (P < 0.001). The results suggest that this new method to determine skeletal maturation is very reliable. A simple method based on morphological characteristics of the cervical vertebral bodies to evaluate the maturation stage has been designed. In the population investigated, this method is as accurate as the Hassel and Farman classification and superior to the Lamparski classification. The morphological vertebral parameter best able to estimate the maturation is the concavity of the lower border of the body.

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The aim of the study was evaluate tooth movement, receptor activator of nuclear factor KB ligand (RANKL), osteoprotegerin (OPG), and RANKL/OPG ratio in gingival crevicular fluid (GCF) in compression side and pain level during initial orthodontic tooth treatment to determine the efficacy of low-level laser therapy (LLLT). Ten volunteers who required fixed appliance positioned from the upper first premolars to upper first molars were selected. For each patient, the upper first premolar of the quadrant 1 was chosen to be irradiated with a laser diode at 670 nm, 200 mW, and 6.37 W/cm(2), applied on the distal, buccal, and lingual sides during 9 min on days 0, 1, 2, 3, 4, and 7. The same procedure was applied in the first premolar of the contralateral quadrant inserting the tip but without laser emission. Samples of GCF from the compression side of the upper first premolars to distalize were collected at baseline and after 2, 7, 30, and 45 days posttreatment for determination of RANKL and OPG by enzyme-linked immunosorbent assay. In addition, tooth movement was assessed by scanning models and pain intensity was assessed using a visual analog scale. There was improvement in the parameters studied (pain, tooth movement, levels of RANKL in GCF, and RANKL/OPG ratio) in the laser group when compared to the control group, although differences were not statistically significant. The accumulated retraction of the upper premolar at 30 days was higher in the laser group, and this difference was statistically significant between groups. LLLT delivered in repeated doses (six times in the initial 2 weeks) leads in some extent to a slight orthodontical improvement.