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Objective: To examine modifications in sleep pattern and in craniofacial morphology of adolescents with mandibular retrognathism. Materials and Methods: Sixteen subjects at maximum pubertal growth (12.6 years [611.5 months]) were selected and treated for 12 months with maxillary expansion and mandibular advancement with a Herbst appliance. Cephalometric radiography and magnetic resonance imaging were obtained prior to and after treatment and were compared using the paired Student's t-test or the nonparametric Wilcoxon rank-sum test. Four polysomnographic recordings were obtained with pressurized nasal cannulae and were analyzed by analysis of variance. Results: The length of the mandible was increased, while the antero-posterior position of the maxilla remained stable. The posterior airway space was increased, the length of the tongue was preserved, and the hyoid bone was moved to a more anterior position. After Herbst treatment, sleep efficiency, sleep latency, rapid eye movement (REM) sleep latency, and percentage of REM sleep remained stable. We did observe a reduction (P , .05) in the relative proportions of stage 1 and stage 3-4 (from 4.30 6 1.99 to 2.61 6 1.83 for stage 1 and from 25.78 6 7.00 to 19.17 6 7.58 for stages 3-4) as well as an increase (P , .01) in the percentage of stage 2 after treatment (49.03 6 6.25 to 56.90 6 6.22). There was a reduction (P , .05) in the number of respiratory effortrelated arousals (7.06 6 5.37 to 1.31 6 1.45 per hour of sleep) due to an increase (P , .01) in airway volume. Conclusions: In the short term, the increase in airway space improved nocturnal breathing associated with the correction of mandibular retrognathism. (Angle Orthod. 2011;81:222-228.)

In the present study, the peri-implant sulcus surrounding failed orthodontic mini-implants did not show a specific aggressive bacterial flora.

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Objective: To verify if mini-implant mobility is affected by the presence of periodontopathogens, frequently associated with peri-implantitis. Materials and Methods: The surfaces of 31 mini-implants used for skeletal anchorage in orthodontic patients were evaluated. Polymerase chain reaction was used for identification of the presence of DNA from three different periodontopathogens (P. intermedia [Pi ], A. actinomycetemcomitans [Aa], and P. gingivalis [Pg]) in 16 mini-implants without mobility (control group) and 15 mini-implants with mobility (experimental group). Results: The results showed that Pi was present in 100% of the samples, from both groups: Aa was found in 31.3% of the control group and in 13.3% of the experimental group. Pg was detected in 37.4% of the control group and in 33.3% of the experimental group. The Fisher exact test and the odds ratio (OR) values for Aa and Pg (OR 5 0.34; 95% confidence interval [CI]: 0.05-2.10 and OR 5 0.61; 95% CI: 0.13-2.79, respectively) showed no significant association (P . .05) between the periodontopathogens studied and the mobility of the mini-implants. Conclusions: It can be concluded that the presence of Aa, Pi, and Pg around mini-implants is not associated with mobility. (Angle Orthod. 2012;82:591-595.)