Gabriele Rossini

Efficacy of clear aligners in controlling orthodontic tooth movement: A systematic review

OBJECTIVE To assess the scientific evidence related to the efficacy of clear aligner treatment (CAT) in controlling orthodontic tooth movement. MATERIALS AND METHODS PubMed, PMC, NLM, Embase, Cochrane Central Register of Controlled Clinical Trials, Web of Knowledge, Scopus, Google Scholar, and LILACs were searched from January 2000 to June 2014 to identify all peer-reviewed articles potentially relevant to the review. Methodological shortcomings were highlighted and the quality of the studies was ranked using the Cochrane Tool for Risk of Bias Assessment. RESULTS Eleven relevant articles were selected (two Randomized Clinical Trials (RCT), five prospective non-randomized, four retrospective non-randomized), and the risk of bias was moderate for six studies and unclear for the others. The amount of mean intrusion reported was 0.72 mm. Extrusion was the most difficult movement to control (30% of accuracy), followed by rotation. Upper molar distalization revealed the highest predictability (88%) when a bodily movement of at least 1.5 mm was prescribed. A decrease of the Littles Index (mandibular arch: 5 mm; maxillary arch: 4 mm) was observed in aligning arches. CONCLUSIONS CAT aligns and levels the arches; it is effective in controlling anterior intrusion but not anterior extrusion; it is effective in controlling posterior buccolingual inclination but not anterior buccolingual inclination; it is effective in controlling upper molar bodily movements of about 1.5 mm; and it is not effective in controlling rotation of rounded teeth in particular. However, the results of this review should be interpreted with caution because of the number, quality, and heterogeneity of the studies.

Diagnostic accuracy and measurement sensitivity of digital models for orthodontic purposes: A systematic review

INTRODUCTION Our objective was to assess the accuracy, validity, and reliability of measurements obtained from virtual dental study models compared with those obtained from plaster models. METHODS PubMed, PubMed Central, National Library of Medicine Medline, Embase, Cochrane Central Register of Controlled Clinical trials, Web of Knowledge, Scopus, Google Scholar, and LILACs were searched from January 2000 to November 2014. A grading system described by the Swedish Council on Technology Assessment in Health Care and the Cochrane tool for risk of bias assessment were used to rate the methodologic quality of the articles. RESULTS Thirty-five relevant articles were selected. The methodologic quality was high. No significant differences were observed for most of the studies in all the measured parameters, with the exception of the American Board of Orthodontics Objective Grading System. CONCLUSIONS Digital models are as reliable as traditional plaster models, with high accuracy, reliability, and reproducibility. Landmark identification, rather than the measuring device or the software, appears to be the greatest limitation. Furthermore, with their advantages in terms of cost, time, and space required, digital models could be considered the new gold standard in current practice.

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.

Periodontal health during clear aligners treatment: a systematic review

BACKGROUND Clear aligner treatment (CAT) has been cited as a safe and comfortable orthodontic procedure for adult patients. However, the available evidence is scarce. OBJECTIVE To perform a systematic review of the existing literature in order to assess periodontal health during CAT. SEARCH METHODS AND SELECTION CRITERIA Pubmed, Pubmed Central, National Library of Medicines Medline, Embase, Cochrane Central Register of Controlled Clinical trials, Web of Knowledge, Scopus, Google Scholar, and LILACS were searched from January 1945 to September 2014 to identify all peer-reviewed papers potentially relevant to the review. DATA COLLECTION AND ANALYSIS After duplicate selection and extraction procedures, the risk of bias was assessed according to the Centre for Reviews and Dissemination criteria, and a 3-point grading system, as described by the Swedish Council on Technology Assessment in Health Care (SBU), was used to rate the methodological quality of the selected papers. A PICOS table was used for data extraction. RESULTS Five relevant articles were selected from the 1247 identified articles. The level of evidence was moderate for all the studies. A significant improvement of the periodontal health indexes was revealed, in particular when CAT was compared to fixed appliances. No periodontal CAT adverse effects were observed in the selected studies. CONCLUSIONS Periodontal health indexes were significantly improved during CAT. The results of this review should be interpreted with some caution because of the number, quality, and heterogeneity of the included studies.

Risk factors related to sleep bruxism in children: A systematic literature review

OBJECTIVE The aim of this article was to systematically review the literature to identify papers dealing with risk factors associated with sleep bruxism (SB) in children. DESIGN A systematic search was carried out based on the following databases: PubMed, Embase, Scopus, Cochrane Oral Health Groups Trial Register and Cochrane Register of Controlled Trials, Web of Science, LILACs, SciELO. Studies investigating risk factors related to SB after multiple regression analysis and bruxism symptoms assessed with clinical diagnosis or specific questionnaires were searched. Six out of the 4546 initially identified studies were selected. This review was conducted according to the guidelines from the Cochrane Handbook for Systematic Reviews of Interventions, with reporting in agreement to the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. RESULTS Among the six analyzed articles, one randomized clinical trial (RCT) suggested the increase of SB in heavily exposed patients to second hand smoke (SHS) (OR=4.5, CI=2.2-9.4), two cross-sectional studies suggested neuroticism as determinant factor for the development of sleep bruxism (OR=1.9, CI=1.3-2.6), among children and three case-control studies suggested that children with sleep disturbances were more likely to have SB (OR=3.3, CI=1.6-6.6). Parafunctional behaviours (OR=2.3, CI=1.2-4.3) had a moderate association. CONCLUSIONS SHS and sleep disturbances presented the strongest association with SB. The most recurrent source of bias was the lack of blinding procedures. Furthermore, the use of reliable SB diagnostic procedures should be recommended to increase the quality of future studies. The evidence emerged from the considered studies was clinically relevant.

Sleep bruxism in adolescents: a systematic literature review of related risk factors.

Background: Multiple risk factors have been associated to sleep bruxism (SB). Nevertheless, there are still many unsolved issues concerning the etiology of SB that have consequences on the clinical management strategies. Objective: Systematically review the literature to assess the relationship between risk factors and SB symptoms in adolescents (age 11–19 years). Search methods and selection criteria: PubMed, Embase, Scopus, Cochrane Oral Health Group’s Trial Register and Cochrane Register of Controlled Trials, Web of Science, LILACs, and SciELO were searched to identify all peer-reviewed articles potentially relevant to the review. Data collection and analysis: The risk of bias was assessed according to the guidelines from the Cochrane handbook for systematic reviews of interventions, with reporting in agreement to the preferred reporting items for systematic reviews and meta-analyses guidelines. Results: Four out of the 4546 initially identified articles were selected. According to the grading of recommendations assessment, development and evaluation assessment (GRADE), the magnitude of agreement was almost perfect for all checklist items. Sleep disturbances, and snoring in particular, headache, jaw muscle fatigue, and tooth wear seem to be associated to SB in adolescents from 11 to 19 years old. Limitations: Despite the large interest of the scientific community in the field of oral parafunctions, only four articles met the eligibility criteria. Furthermore only associations and not definite cause–effect relationships were highlighted in the selected articles. Conclusions: Sleep disturbances presented the strongest association with SB while very few occlusal features had a moderate association. As a common sense the investigation of sleep respiratory disorders could be of great help in the management of SB in adolescents.

Sleep bruxism and related risk factors in adults: A systematic literature review

OBJECTIVE The aim of this article was to systematically review the literature to assess the relationship between risk factors and sleep bruxism (SB) in adults (age ≥18 years). DESIGN A systematic search of the following databases was carried out: PubMed, Embase, Scopus, Cochrane Oral Health Groups Trial Register and Cochrane Register of Controlled Trials, Web of Science, LILACs and SciELO. Nine out of the 4583 initially identified articles were selected. This review was conducted according to the guidelines from the Cochrane Handbook for Systematic Reviews of Interventions, with reporting in agreement to the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. RESULTS Among the nine analyzed articles, associations between SB and gastro-esophageal reflux disease (GERD) (OR=6.6, CI=1.4-30.9) was found in one randomized clinical trial (RCT). Four cross-sectional studies suggested history of SB during childhood (OR=8.1 CI=5.4-12-2), age (OR=3.1, CI=2.3-4.1) and chronic migraine (OR=3.8, C.I=1.8-7.8) as determinant factors for the development of SB. In one case-control study, patients with genetic polymorphisms were more likely to present SB (OR=4.3, CI=1.6-11.3). Smoking (OR=2.8, CI=2.2-3.5) and alcohol intake (OR=1.9, CI=1.2-2.8) showed moderate association in two case-control studies. CONCLUSIONS History of SB during childhood, gastro-esophageal reflux disease and genetic polymorphisms seem to be important risk factors associated to SB in adults. Dry mouth on awakening seems to be a protective factor. Association does not infer with causality. Even if the evidence emerged from the considered studies was clinically relevant, further studies are requested to better understand the biological mechanisms behind the described associations.

Mandibular distraction osteogenesis: a systematic review of stability and the effects on hard and soft tissues

Mandibular distraction osteogenesis (MDO) has been widely adopted in modern maxillofacial surgery due to its less invasive approach and the consistent aesthetic and functional improvements obtained. The aim of the present systematic review was to analyze the available evidence on the skeletal and soft tissue effects of MDO. The medical literature was searched to identify all peer-reviewed papers meeting the selection criteria for the final review process. A three-point grading system was used to rate the methodological quality of the selected papers. The PICO approach was used to extract data from the selected papers. The search strategy yielded eight relevant publications. The quality of the collected evidence was low to moderate. Vertical and sagittal skeletal dimensions increased significantly, by a mean of 5-10mm (P<0.05). Regarding the sagittal positioning of the lips and surrounding structures, a 90% correspondence between skeletal and soft tissue cephalometric points was observed. Significant skeletal relapse was reported, however it did not worsen the results of treatment significantly.

Scanning electron microscopy evaluation of aligner fit on teeth

OBJECTIVES The fitting of aligners on anchorage teeth is a crucial factor in clear aligner orthodontics. The purpose of this experimental study was to evaluate the fitting of two aligner systems, Invisalign and CA-Clear Aligner, using scanning electron microscopy (SEM). MATERIALS AND METHODS Passive aligners (Invisalign and CA-Clear Aligner) were adapted on resin casts obtained by stereolithography (STL) files of a patient, and then sectioned buccolingually. Upper and lower central incisors, upper and lower first premolars, and upper and lower first molars were the regions analyzed. Representative microphotographs of sections were taken with a scanning electron microscope (SEM); a total of 160 micrometric measurements were obtained and analyzed with ANOVA tests. RESULTS Invisalign provided an overall better fit on lower incisors ( F = 11.48, P = .0095) and on lower molars ( F = 19.93, P = .0012). Considering the different regions, Invisalign provided better fit at the gingival edge of the buccal aspect on lower incisors ( F = 11.33, P = 0.0056) and at the gingival edge of the lingual aspect on upper premolars ( F =5.34, P = 0.0047). On the upper molars, Invisalign provided better fit at the gingival edge of the buccal aspect, while CA-Clear Aligner provided better fit at the buccal maximum convexity, on the buccal cusp, on the occlusal groove and at the palatal cusp. On lower molars, Invisalign showed a more accurate fit at the buccal aspect points. CONCLUSIONS Invisalign and CA-Clear Aligner exhibited comparable fit on anchorage teeth. Invisalign provided better fit at the gingival edges of aligners, while the CA-Clear Aligner provided better fit on complex occlusal surfaces.

Root resorption during orthodontic treatment with Invisalign®: a radiometric study

BackgroundRoot resorption (RR) is described as a permanent loss of tooth structure from the root apex. Many reports in the literature indicate that orthodontically treated patients are more likely to have severe apical root shortening, interesting mostly maxillary, followed by mandibular incisors. The aim of the study was to investigate the incidence and severity of RR in adult patients treated with aligners. The study group consisted of 71 class I adult healthy patients (mean age 32.8 ± 12.7) treated with aligners (Invisalign®, Align Technologies, Santa Clara, CA, USA). All incisors, canines, upper first premolars, and first molars were assessed. Root and crown lengths of 1083 teeth were measured in panoramic radiographs at the beginning (T0) and at the end (T1) of clear aligner therapy. Individual root-crown ratio (RCR) of each tooth and therefore the relative changes of RCR (rRCR) were determined. A decrease of rRCR was assessed as a reduction of the root length during treatment.ResultsAll patients had a minimum of one teeth affected with a reduction of root length, on average 6.38 ± 2.28 teeth per patient. Forty one, 81% of the 1083, measured teeth presented a reduction of the pre-treatment root length. A reduction in percentage of >0% up to 10% was found in 25.94% (n = 281), a distinct reduction of >10% up to 20% in 12.18% (n = 132) of the sample. 3.69% (n = 40) of the teeth were affected with a considerable reduction (>20%).ConclusionsOrthodontic treatment with Invisalign® aligners could lead to RR. However, its incidence resulted to be very similar to that described for orthodontic light forces, with an average percentage of RR < 10% of the original root length.