This prospective longitudinal study assessed the 3D soft tissue changes following mandibular advancement surgery. Cranial base registration was performed for superimposition of virtual models built from cone beam computed tomography (CBCT) volumes. Displacements at the soft and hard tissue chin (n=20), lower incisors and lower lip (n=21) were computed for presurgery to splint removal (4-6 week surgical outcome), presurgery to 1 year postsurgery (1-year surgical outcome), and splint removal to 1 year postsurgery (postsurgical adaptation). Qualitative evaluations of color maps illustrated the surgical changes and postsurgical adaptations, but only the lower lip showed statistically significant postsurgical adaptations. Soft and hard tissue chin changes were significantly correlated for each of the intervals evaluated: presurgery to splint removal (r=0.92), presurgery to 1 year postsurgery (r=0.86), and splint removal to 1 year postsurgery (r=0.77). A statistically significant correlation between lower incisor and lower lip was found only between presurgery and 1 year postsurgery (r=0.55). At 1 year after surgery, 31% of the lower lip changes were explained by changes in the lower incisor position while 73% of the soft tissue chin changes were explained by the hard chin. This study suggests that 3D soft tissue response to mandibular advancement surgery is markedly variable.
Introduction-In this in-vitro study, we aimed to compare the residual monomers in composites beneath brackets bonded to enamel, using a light-emitting diode (LED) or a halogen unit, and to compare the residual monomers in the central to the peripheral areas of the composite.
Objective: To examine levels of matrix metalloproteinases (MMPs)-1, -2, -3, -7, -8, -12, and -13 in the gingival crevicular fluid (GCF) of periodontally compromised teeth at different time points during orthodontic movement. Materials and Methods: Ten controlled periodontitis subjects were submitted to orthodontic treatment. One dental arch was subjected to orthodontic movement, and teeth in the opposite arch were used as controls. GCF samples were collected from the lingual sites of two movement and two control incisors 1 week before orthodontic activation (27 d), immediately after orthodontic activation, and after 1 hour, 24 hours, and 7, 14, and 21 days. Multiplexed bead immunoassay was used to measure MMPs in GCF. Data were analyzed using Friedman and Wilcoxon statistical tests. Results: The only significant change found over time was in the levels of MMP-1 in the movement group (P , .05). When the two groups were compared after activation, the only statistically significant difference found was in levels of MMP-12 24 hours after activation (P , .05). Conclusions: Our findings suggested that the orthodontic movement of periodontally compromised teeth without active pockets did not result in significant changes in the GCF levels of MMPs.
OBJECTIVE: To identify most frequent clinical conducts, considering the following variables: 1) used appliances; 2) time of use; 3) protocol of use in daily hours and evolution with along time; 4) percentage of patients in follow up 1 year after treatment; and 5) most frequent observed relapses.. METHODS: It was used a questionnaire distributed to all specialization course of Orthodontics inscribed in the Brazilian Federal Council of Dentistry until October of 2005. RESULTS AND CONCLUSION: It was obtained 91 valid questionnaires. For data analysis were used descriptive statistics and chi-square for linear tendency and chi-square for linear trend and chi-square for multivariate linear trend. We can conclude that: 1) on upper arch, the most used appliances were Hawley, wraparound and acetate plate; in the lower multi-stranded rod, steel rod not bonded to incisors and rod bonded to the incisors; 2) it was indicated its use for more than 24 months for the upper arch, with a trend toward its less use than in the lower arch; 3) the protocol of use in the upper arch begins with 24 hours/day, reducing after the second year; for the lower arch the protocol of hours/day was kept stable; 4) after 1 year of retention most than 50% of treated cases were re-examined; 5) most common relapses were crowding, giroversion and opening of diastemas.
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