Short term dentoskeletal effects of mandibular advancement clear aligners in Class II growing patients. A prospective controlled study according to STROBE Guidelines.

AIM: To evaluate the dentoskeletal effects of the Invisalign® Mandibular Advancement (MA) (Align Technology, San José, CA, USA) feature in skeletal Class II growing patients with mandibular retrusion, at pre-pubertal and pubertal stages. MATERIALS AND METHODS: Study design: Forty skeletal Class II patients were prospectively recruited and treated with Invisalign® MA. They were divided into two subgroups according to the CVM stage of growth (CVM2 and CVM3) at the beginning of treatment (T0). For each patient, lateral radiographs were collected at the beginning (T0) and at the end of the mandibular advancement treatment (T1) and their measurements were compared with those obtained by an untreated control group of 32 subjects, matched for growth stage and malocclusion. RESULTS: Patients in CVM2 showed significant reduction of ANB angle, A:Po, Wits index, 11^Spp angle and significant increase of 11^41 and B Downs point. In CVM3 significant reduction of the Wits index and of 41^GoGn angle, and significant increase of the linear Co-Gn measurement, were revealed. STATISTICS: The STROBE guidelines were followed. Linear regression analysis was performed to estimate the differences of ? (T1 - T0) means between group (control was used as reference) stratifying by CVM levels. CONCLUSION: The use of Invisalign® MA is effective in treating Class II growing patient with retrognathic mandible in the short term period. While treatment at prepubertal stage of growth results in dentoalveolar rather than skeletal effects, treatment during the pubertal spurt produces skeletal effects with an annual rate of change of 5.8 mm.

Interceptive treatment effects of EF preformed appliance in pre-pubertal and pubertal skeletal Class II growing patients: A retrospective controlled study.

AIM: Interceptive treatment has been devised to improve the outcomes on growth stage and mandibular repositioning in Class II patients. The aim of this study is to test the effectiveness of Functional education (EF) (OrthoPlus, Igny, France) preformed appliance in skeletal Class II growing patients at CVM2 and CMV3 stages. MATERIALS AND METHODS: Study design: retrospective controlled study. Eighty skeletal Class II growing subjects were recruited for the study. Lateral X-rays and cephalograms were required at the beginning (T0) and at the end (T1) of the EF treatment to evaluate dento-skeletal changes. The same sub-division and sample size were adopted for respective untreated control groups. RESULTS: At prepubertal stage, the EF device showed a significant reduction of upper incisors proclination. When comparing dentoskeletal variables in the pubertal groups, significant differences were shown. In the treated group the SN^B angle increased, with the B Downs landmark moving forward. Wits index improved by 2.16 mm in the study group with an increase of all mandibular linear measurements. Fewer but significant dental changes were shown for 11^41 angle, with a mean increase of 8.90°. STATISTICS: For multiple comparisons, the Tukey test at 95% family-wise confidence level was used. The level of significance was set at p < 0.05. Statistical analyses were conducted using the R statistical package (version 3.0.3, R Core Team, Foundation for Statistical Computing, Vienna, Austria). CONCLUSIONS: EF appliance seems to be effective in the treatment of Class II growing patients. Significant improvements in upper incisors proclination and mandibular elongation are shown.

Effects of clear aligners on sleep bruxism: randomized controlled trial.

The possible effects on sleep bruxism (SB) of clear aligners in orthodontics are unknown. This study was conducted to analyze the effects of clear aligners on SB. Sixty subjects needing orthodontic treatment and affected by SB (33 m, 27 f, 20±;5 years) were enrolled in the study and randomly assigned to one of the following three groups: 20 were given clear aligners (CAT) (12 m, 8 f, 19±5 years), 20 occlusal splint (MOS) (9 m, 11 f, 22±5 years) and 20 a placebo splint (PMS) (12 m, 8 f, 24±3 years). All groups were followed for 6 consecutive months and monitored for SB with a portable electromyographic-electrocardiographic (EMG-ECG) device (Bruxoff®, OT Bioelettronica, Torino, Italy). MOS subjects reduced masseter contractions after 6 months of treatment (t3) (MD=-29.11, std. error 11.74, p=0.017) but increased phasic contractions related to SB after 3 months of treatment (t2) (MD=4.73, std. error 2.36, p=0.048) and tonic contractions related to SB during all the six months of treatment (t1, t2, t3) when compared to PMS. CAT subjects increased phasic contractions related to SB during the first (t1) (MD=3.94, std. error 2.27, p=0.04) and the third month (t2) of treatment (MD=4.62, std. error 2.36, p=0.046) when compared to PMS. No significant differences were found for SB index at any time for all the three groups. Although MOS and CAT affected EMG signals during sleep time differently, they did not influence the overall SB index.

Agreement between clinical and portable EMG/ECG diagnosis of sleep bruxism.

The aim of this study was to compare clinical sleep bruxism (SB) diagnosis with an instrumental diagnosis obtained with a device providing electromyography/electrocardiography (EMG/ECG) recordings. Forty-five (N = 45) subjects (19 males and 26 females, mean age 28 ± 11 years) were selected among patients referring to the Gnathology Unit of the Dental School of the University of Torino. An expert clinician assessed the presence of SB based on the presence of one or more signs/symptoms (i.e., transient jaw muscle pain in the morning, muscle fatigue at awakening, presence of tooth wear, masseter hypertrophy). Furthermore, all participants underwent an instrumental recording at home with a portable device (Bruxoff; OT Bioelettronica, Torino, Italy) allowing a simultaneous recording of EMG signals from both the masseter muscles as well as heart frequency. Statistical procedures were performed with the software Statistical Package for the Social Science v. 20.0 (SPSS 20.0; IBM, Milan, Italy). Based on the EMG/ECG analysis, 26 subjects (11 males, 15 females, mean age 28 ± 10 years) were diagnosed as sleep bruxers, whilst 19 subjects (7 males, 12 females, mean age 30 ± 10 years) were diagnosed as non-bruxers. The correlation between the clinical and EMG/ECG SB diagnoses was low (ϕ value = 0.250), with a 62.2% agreement (28/45 subjects) between the two approaches (kappa = 0.248). Assuming instrumental EMG/ECG diagnosis as the standard of reference for definite SB diagnosis in this investigation, the false-positive and false-negative rates were unacceptable for all clinical signs/symptoms. In conclusion, findings from clinical assessment are not related with SB diagnosis performed with a portable EMG/ECG recorder.