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Bacterial adhesion to the surface of the adhesive material is an important step in the formation of plaque and enamel demineralization. In order to correlate the material composition to the specific surface roughness of the resin and to the probable more favourable adhesion of bacteria, scanning electron microscopy, combined with focus ion bean micromachining, together with stylus profilometry analysis have been in vitro performed to reveal the structural nature of three orthodontic adhesive resins used for bracket bonding and, above all, to understand how compositional factors can influence specific pivotal properties such as material’s surface roughness and robustness. In particular, we speculated about the morphological features that determine an increase in the bacterial adhesion and we proposed focused ion beam technique as a valuable tool to compare the internal structures of the polymers and to determine the peculiar mechanical properties of the examined adhesive resins.

The histological and histomorphometrical examination were the gold standard in the qualitative and quantitative analyses of the peri-implant tissue around the implant. In recent years, the field of microscopy has witnessed a considerable enhancement of the performance of microscopes that have very high resolution performance and allowing very sophisticated analysis even larger than traditional preparations. The possibility to have an affordable analyses of whole implant with the surrounding different tissues (soft and hard tissues) without the traditional pre-treatment necessary for the histological analysis may represent a goal to describe material properties and behaviors or simply to visualize structural details. The aim of the present study were to evaluate a 3D X-ray microscopic analysis of peri-implant tissue compared to a traditional histological and histomorphometrical analysis of the peri-implant tissues around an implant with a conical connection associated with platform-switching in order to assess the validity of the new analysis technique.

Adenotonsillectomy is not always successful in controlling obstructive sleep apnea (OSA) in children, and orthodontic treatment may be a helpful adjunction and sometime an important alternative. A total of 80 nonoverweight children (37 girls) with a high and narrow hard palate, based on an indepth orthodontic evaluation, were subdivided into two groups based on presence/absence of chronic adenotonsillar inflammatory problems as determined by full otolaryngological examination, with recruitment of 40 children in each group. Patients with evidence of chronic inflammation were treated with adenotonsillectomy first (group II), while all other children had rapid maxillary expension (RME) first (group I). In all children, clinical interviews and clinical evaluations, frontal and lateral cephalometry, and polysomnography were performed at entry. Four months after end of treatment, the initial evaluation was repeated in all children. Children incompletely treated were offered to cross-over to the other treatment venue. At entry, there was no significant difference between the monitored respiratory polygraphic variables between the two groups. At the 4-month follow-up, 15 subjects treated with RME were considered as cured compared to 6 patients after adenotonsillectomy, and absence of improvement was observed in 8 children with RME and 16 with adenotonsillectomy. After cross-over to the other treatment, involving 42 subjects due to 17 drop-outs between treatment 1 and 2,, three children were still having residual sleep disordered breathing at the 12-month follow-up, while normal breathing during sleep was observed in all others. With appropriate clinical investigation, prepubertal children with OSA and narrow maxilla may have better treatment outcome when treated with orthodontics than with adenotonsillectomy; and polygraphic and even better polysomnographic documentation of clinical impression is always needed posttreatment.

When both narrow maxilla and moderately enlarged tonsils are present in children with obstructive sleep apnea, the decision of which treatment to do first is unclear. A preliminary randomized study was done to perform a power analysis and determine the number of subjects necessary to have an appropriate response. Thirty-one children, 14 boys, diagnosed with OSA based on clinical symptoms and polysomnography (PSG) findings had presence of both narrow maxillary complex and enlarged tonsils. They were scheduled to have both adeno-tonsillectomy and RME for which the order of treatment was randomized: group 1 received surgery followed by orthodontics, while group 2 received orthodontics followed by surgery. Each child was seen by an ENT, an orthodontist, and a sleep medicine specialist. The validated pediatric sleep questionnaire and PSG were done at entry and after each treatment phase at time of PSG. Statistical analyses were ANOVA repeated measures and t tests.The mean age of the children at entry was 6.5 ± 0.2 years (mean ± SEM). Overall, even if children presented improvement of both clinical symptoms and PSG findings, none of the children presented normal results after treatment 1, at the exception of one case. There was no significant difference in the amount of improvement noted independently of the first treatment approach. Thirty children underwent treatment 2, with an overall significant improvement shown for PSG findings compared to baseline and compared to treatment 1, without any group differences.This preliminary study emphasizes the need to have more than subjective clinical scales for determination of sequence of treatments.

Objective: To evaluate the effect of rapid maxillary expansion on children with nasal breathing and obstructive sleep apnea syndrome. Method: Recruitment of children with maxillary contraction, without of adenoid hypertrophy, with a body mass index < 24 kg/m2, with obstructive sleep apnea syndrome demonstrated by polysomnography, and whose parents signed informed consent. Otolaryngologic and orthognathic-odontologic evaluation with clinical evaluation, anterior rhinometry and nasal fibroscopy, panoramic radiographs, anteroposterior and laterolateral telecephalometry were performed at entry and follow-up. Intervention: Rapid maxillary expansion (ie, active phase of treatment) was performed for 10 to 20 days; maintenance of device (for consolidation) and orthodontic treatment on teeth lasted 6 to 12 months. Results: 31 children (19 boys), mean age 8.7 years, participated in the study. The mean apnea-hypopnea index was 12.2 events per hour. At the 4-month follow-up, the anterior rhinometry was normal, and all children had an apnea-hypopnea index < 1 event per hour. The mean cross-sectional expansion of the maxilla was 4.32 +/- 0.7 mm. There was a mean increase of the pyriform opening of 1.3 +/- 0.3 mm. Conclusion: Rapid maxillary expansion may be a useful approach in dealing with abnormal breathing during sleep.

Children who suffer from respiratory problems and obstructive sleep apnea (OSA) commonly exhibit disturbances of craniofacial morphology. A significant number have nasal obstruction associated with a narrow maxilla; maxillary constriction may increase nasal resistance and alter the tongue posture, leading to narrowing of the retroglossal airway and OSA. Sixty children with a case history of oral breathing, snoring, and night time apneas were studied. An orthognathodontic investigation was performed using radiographs that included not only the usual examinations (posteroanterior cephalographs and intraoral radiographs) but also computed tomographic scans. This article discusses the materials and methods and the results of this study.