Sagittal dentoskeletal modifications associated with different activation protocols of rapid maxillary expansion.

AIM: The aim of this study is to compare the sagittal dentoskeletal changes associated with different activation protocols of maxillary expander. MATERIALS AND METHODS: A total of 101 subjects with constricted maxillary arches (49 males and 52 females; mean age 10.08 ± 1.57 years) were enrolled in the study. The study comprised also a control group of 20 subjects (11 females and 9 males, mean age 10.27 ± 1.24 years) who were not treated during the observation period. All the subjects underwent rapid maxillary expansion with a stainless steel banded expander cemented to the maxillary first molars. The expansion screw was randomly activated with two different rapid maxillary expansion protocols (one-quarter per day or two-quarters per day). A statistical comparison between the sagittal cephalometric variations obtained in the two expansion groups was made, and compared with the untreated control group. Data were then stratified for skeletal maturation of each subject. RESULTS: The Wilcoxon rank-sum test shows statistically significant differences between the two RME activation protocols only for overjet. Statistically significant differences were reported in comparison with the control group. CONCLUSIONS: This study suggests that the increase in overjet after RME could be associated with faster activation protocols especially in subjects with lower skeletal maturation.

A comparative assessment of changes in dental arches associated with different activation protocols of rapid maxillary expansion.

AIM: The aim of this study is to compare dental arch changes associated with different activation protocols of maxillary expander. MATERIALS AND METHODS: A sample of 101 subjects with constricted maxillary arches (49 males and 52 females; mean age 10.96 ± 1.91 years) was enrolled in the study. All subjects underwent RME with a stainless steel banded expander cemented to the maxillary first molars and the expansion screw was randomly activated with two different rapid maxillary expansion protocols (one- quarter per day or two quarters per day). The study also involved a control group of 22 subjects (10 females and 12 males, mean age 10.39 ± 1.32 years) who underwent no treatment. A statistical comparison between the dental arch measures obtained before and after treatment in the two groups was performed. RESULTS: The Wilcoxon rank-sum test shows statistically significant differences of the measurement increases between the two activation protocols (at least p=0.01). Statistically significant differences were also reported in comparison with the control group. CONCLUSIONS: A faster activation protocol could be able to determine a greater anterior opening of the mid-palatal suture. Moreover, it seems to yield a higher width increase in the molar area.

Analysis of rapid maxillary expansion effects on nasal soft tissues widths.

AIM: The aim of this study was to analyze the variations in nasal dimensions in prepubertal patients associated with RME therapy compared with an untreated age matched control group. METHODS: A group of 61 subjects (26 F, 35 M; mean age 10.5±1.8 years) was enrolled in the study to undergo a rapid maxillary expansion therapy; 41 subjects (26 F, 15 M; mean age 10.7±2.2 years) were enrolled as a control group. Both groups underwent nasal soft tissues width measurements using a caliper at three separate time points: T0 - prior to the placement of RME; T1 - after completion of active expansion phase; T2 - at the removal of the expander (nearly 6 months after T1). RESULTS: The ANOVA showed statistically significant increments (P<0.0001) of the greater alar cartilage (GAC) measurement (0.8±0.2 mm) in the study group, differences for the AB measurements were not statistically significant (P=0.0784). CONCLUSION: The treatment of rapid maxillary expansion can induce an increase in GAC soft tissues width of about 1 mm in prepubertal patients. This increase could not be considered of clinical impact. The alar base width increase less than GAC, this increase is without statistical significance.

Low-dose CT protocol for orthodontic diagnosis.

AIM: This was to correlate the dosimetric evaluation with high diagnostic accuracy by suggesting a protocol that significantly reduces the dose administered by a Dentascan exam without affecting diagnostic accuracy. MATERIALS AND METHODS: 17 patients were selected consecutively (7 males and 10 females) of a mean age of 11.2 (8-14 years) who sought orthodontic treatment. They needed CT control before and after treatment with RME to evaluate impacted canines. The study was performed using a multidetector 16-rows CT with two protocols that provided 2 different KV acquisition parameters: 80 KV or 120 KV. Radiation dose was evaluated in two ways: CTDI and DLP. Image quality was rated and the results were compared to identify significant differences in terms of image quality, radiation exposure and presence of artefacts. RESULTS: The 80 KV scanning has a significantly lower effective radiation dose compared to the 120 KV scanning (p <0.05). The images of all patients were used for comparing the protocols in terms of image quality. The mean scores for the 80 KV scanning images were 4.18 +/-0.81 and 4.41 +/-0.80 for dose obtained by 120 KV scanning. The median image quality was 4 (good) for both protocols. The 80 KV protocol allowed, as well as the 120 KV, a careful analysis by the orthodontist and the dental surgeon that together, based on this images, can choose the best line of treatment between several available options. CONCLUSION: 80 KV protocols compared with 120 KV protocols resulted in reduced total radiation dose without relevant loss of diagnostic image information and quality. The images were good enough to obtain information about the exact position of impacted teeth and to plan the best line of surgical treatment and mechanotherapy strategy.

Post-retention effects of rapid maxillary expansion on nasal cavity and on periodontal structures.

AIM: The aim of this study was to apply low-dose CT scans to evaluate the treatment and post-retention effects of RME on nasal cavity and periodontal effects. MATERIALS AND METHODS: CT scans of 17 subjects (7 males 10 females, mean age 11.2 years) were taken before RME (T0), at the end of the expansion phase (T1), and after a retention period of 6 months (T2). Measurements were performed on axial scans and on 3 different coronal scans. Statistical analysis was performed with ANOVA for repeated measures with post-hoc tests. RESULTS: Transverse dimensions of nasal cavity showed statistically significant T0-T1 increments at all the 3 coronal scans. All T0-T1 increments at the nasal levels showed a decrease in magnitude from the anterior to the posterior measurements. In the evaluation of T0-T1 changes, periodontal measurements were significant on the buccal aspect of banded teeth with a reduction in alveolar bone thickness. In the evaluation of T0-T2 changes, the lingual bone plate thickness resulted significantly increased. CONCLUSIONS: RME therapy induces a significant increase in the transverse dimension of the nasal cavity without permanent injuries to the periodontal bony support discernible at CT imaging. After six months the expansion of the nasal cavity results stable.

Orthodontist-otorhinolaryngologist: an interdisciplinary approach to solve otitis media.

AIM: This was to investigate in oral breathing children with an associated atypical pattern of swallowing and otitis media, the effects of rapid maxillary expansion on nasal airway resistance and conductive hearing loss. MATERIALS AND METHODS: This study examined 24 children (16 males and 8 females) in early mixed dentition period, with an age range of 6-8 years (mean age 7 years), diagnosed with otitis media from the otorhinolaryngology Department of "Tor Vergata" Hospital. The young patients were seen in the Department of Orthodontics, Faculty of Dentistry University of Rome "Tor Vergata". All the subjects had an open mouth breathing pattern with a secondary atypical swallowing mode and a conductive hearing loss resulting from otitis media. The therapeutic approach was to apply a RPE fixed appliance (Butterfly expander). RESULTS: Follow up showed that after rapid maxillary expansion there was nasal resistance reduction, increased nasal airflow and improvement in conductive hearing loss. CONCLUSION Rapid maxillary expansion has been used for both dental and rhinological purposes in the belief that clinically significant reductions in nasal resistance to airflow and an improvement in conductive hearing loss occur predictably.

Supernumerary teeth and mental retardation: the importance of early surgical intervention.

AIM: This paper reported a rare case of hyperdontia in a child of 10 years who revealed a mixed dentition and a light mental retardation. MATERIALS AND METHODS: The therapeutic approach has been based on interdisciplinary cooperation between the pediatric dentist, orthodontist and oral surgeon. TC-Dentascan, with a panoramic and occlusal radiographs revealed the presence of two supernumerary teeth in the premaxillary region and clinical examination showed an abnormality of dentoalveolar complex. Both impacted supernumerary teeth were extracted under general anesthesia. Clinical examination revealed that they appeared two premolars in shape with fully formed crowns and partly formed roots. RESULTS: Three months after the extraction of supernumerary teeth there was a spontaneous eruption of permanent central incisors and left lateral incisor. CONCLUSION: The authors emphasized the importance of removal of supernumerary teeth to eliminate the cause of a delayed eruption of permanent teeth.

A case of an unerupted maxillary central incisor for indirect trauma localized horizontally on the anterior nasal spine.

The present paper emphasizes the importance of early diagnosis of retarded eruption because of trauma and the plan for the surgical management of impacted teeth. The permanent incisor was localized horizontally on the nasal spine and the roots seemed to be in a retarded stage of formation beside of contralateral tooth. The treatment plan consisted in the valuation of the necessity of space to move the impacted incisor in the normal position and the biomechanical approach for the anchorage.

Case report: severe infraocclusion ankylosis occurring in siblings.

AIM: This was to report a rare case of strong familiar tendency of ankylosis of maxillary second primary molars. CASE REPORT: Three Caucasian children, male twins of 8.5 years and a sister of 10 years, were diagnosed as having severely infraccluded maxillary second primary molars with underlying second premolars. In all three cases, the early extraction of the infraoccluded molars and an active treatment with cervical extraoral traction allowed the physiologic eruption of second premolars. Follow-up showed that normal vertical relationship and bone height had been obtained. CONCLUSION: Early diagnosis, as well as appropriate treatment and careful follow-up are very important in the presence of severe infraocclusion, when the marginal ridge of affected primary teeth is at or below gingival level.

Management of obstructive sleep apnoea in children with modified monobloc appliances.

AIM: This was to investigate the effect of the use of an orthodontic appliance in the treatment of obstructive sleep apnoea (OSA) in children using polysomnographic variables. METHODS: 10 boys and 10 girls with OSA aged between 4 to 8 years, referred from an otolaryngology clinic because of sleep apnoea, wore modified monobloc devices nightly for 6 months. Polysomnography was used for each patient for baseline diagnosis of OSA and also for post therapy assessment. RESULTS: The median obstructive apnoea- hypopnoea index decreased after 6 months of therapy with oral appliances. The mean (+/-SD) number of episodes of OSA was 7.88+/-1.81 before treatment and 3.66+/-6.80 after 6 months (p<0.001). CONCLUSIONS: The modified monobloc appliance is suggested for use in children with OSA and may be an effective therapeutic alternative in children with mild to moderate OSA.