Recent advances of drugs monitoring in oral fluid and comparison with blood.

The use of alternative matrices in toxicological analyses has been on the rise in clinical and forensic settings. Oral fluid (OF), as non-invasive fluid, has attracted attention in the field of drug screening, both for therapeutic and forensic purposes, as well as for medical diagnosis, clinical management, on-site (real time) doping and for monitoring environmental exposure to toxic substances. A good correlation between OF and blood is now established for drug concentrations. Therefore, OF might be a potential substitute of blood, especially for long-term surveillance (e.g., therapeutic drugs) or to screen a large number of patients, as well as for the development of salivary point-of-care technologies. In this review, we aimed to summarize and critically evaluate the current literature that focused on the comparison of drugs detection in OF and blood specimens.

Accuracy of automated 3D cephalometric landmarks by deep learning algorithms: systematic review and meta-analysis.

OBJECTIVES: The aim of the present systematic review and meta-analysis is to assess the accuracy of automated landmarking using deep learning in comparison with manual tracing for cephalometric analysis of 3D medical images. METHODS: PubMed/Medline, IEEE Xplore, Scopus and ArXiv electronic databases were searched. Selection criteria were: ex vivo and in vivo volumetric data images suitable for 3D landmarking (Problem), a minimum of five automated landmarking performed by deep learning method (Intervention), manual landmarking (Comparison), and mean accuracy, in mm, between manual and automated landmarking (Outcome). QUADAS-2 was adapted for quality analysis. Meta-analysis was performed on studies that reported as outcome mean values and standard deviation of the difference (error) between manual and automated landmarking. Linear regression plots were used to analyze correlations between mean accuracy and year of publication. RESULTS: The initial electronic screening yielded 252 papers published between 2020 and 2022. A total of 15 studies were included for the qualitative synthesis, whereas 11 studies were used for the meta-analysis. Overall random effect model revealed a mean value of 2.44 mm, with a high heterogeneity (I2 = 98.13%, τ2 = 1.018, p-value < 0.001); risk of bias was high due to the presence of issues for several domains per study. Meta-regression indicated a significant relation between mean error and year of publication (p value = 0.012). CONCLUSION: Deep learning algorithms showed an excellent accuracy for automated 3D cephalometric landmarking. In the last two years promising algorithms have been developed and improvements in landmarks annotation accuracy have been done.

Detection and sensing of oral xenobiotics in edentulous patients rehabilitated with titanium dental implants: Insights from a scoping review.

STATEMENT OF PROBLEM: Titanium has been considered the standard element in implant manufacturing. Recent studies have evaluated the role of titanium as a biological modulator of oral health. However, evidence regarding the association between the release of metal particles and peri-implantitis is lacking. PURPOSE: The purpose of this scoping review was to evaluate the literature regarding the release of metal particles in peri-implant tissues correlated with the methods of detection and the local and systemic implications. MATERIAL AND METHODS: The study was performed in adherence with the Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) guidelines and was registered with the National Institute for Health Research PROSPERO (Submission No. 275576; ID: CRD42021275576). A systematic search was conducted in the Cochrane Central Register of Controlled Trials, EMBASE, MEDLINE via PubMed, Scopus, and Web of Science bibliographic databases, complemented by a manual evaluation. Only in vivo human studies written in the English language and published between January 2000 and June 2022 were included. RESULTS: In total, 10 studies were included according to eligibility criteria. Different tissues and analytic techniques were reported: the characterization technique most used was inductively coupled plasma mass spectrometry. All 10 studies analyzed the release of metal particles in patients with dental implants, continuously detecting titanium. None of the studies reported a significant association between metal particles and biological effects. CONCLUSIONS: Titanium is still considered the material of choice in implant dentistry, despite the detection of metal particles in peri-implant tissues. Further studies are necessary to evaluate the association between analytes and local health or inflammatory status.

Clinical efficacy of a new cetylpyridinium chloride-hyaluronic acid-based mouthrinse compared to chlorhexidine and placebo mouthrinses-A 21-day randomized clinical trial.

OBJECTIVE: To compare the effectiveness of a novel cetylpyridinium chloride (CPC)-hyaluronic acid (HA)-based mouthrinse with chlorhexidine (CHX) and placebo mouthrinses in preventing plaque and gingivitis. The secondary outcomes were calculus, extrinsic stains, oral malodour and occurrence of adverse events. METHODS: A 21-day randomized, double-blind, three-arm parallel study with random allocation of young dental students to any of the three mouthrinse groups. Thorough prophylaxis was done at baseline followed by a baseline examination for oral malodour, extrinsic stains, calculus, gingivitis and plaque by a single examiner. All the subjects used the allocated mouthrinse twice daily for 21 days and were examined again at the end of the experimental period. They were also interviewed for adverse events. Change in the scores of clinical indices was calculated and compared between the groups. RESULTS: A total of 75 subjects were included and completed the experiment. There was a significant difference for change in plaque index scores between the groups (P = .015); subjects in the placebo group experienced higher levels of plaque accumulation than the other groups. Teeth staining increased in the CHX (P < .001) and placebo groups (P = .002), but not in CPC-HA users (P = .573). No significant differences were found between the three experimental groups for change in the gingival index (P = .08), calculus scores (P = .494), oral malodour (P = .870) and reporting of adverse events (P = .249). CONCLUSIONS: CPC-HA and CHX had similar effectiveness in preventing plaque accumulation, while no differences were observed between the mouthrinses for preventing gingivitis. Dental staining was caused by CHX and the placebo mouthrinses but not by CPC-HA mouthrinse.

Seven-year prospective clinical study on zirconia-based single crowns and fixed dental prostheses.

OBJECTIVES: Zirconia-based prostheses are used for esthetic crown and fixed restorations, but follow-ups are still limited. The authors evaluated the 7-year clinical results of 303 zirconia core restorations, performed in a general dental private practice. MATERIALS AND METHODS: Clinical events (fracture and loss of retention, gingivitis, tenderness, excess cement, and temporary pain) were recorded in 303 zirconia core restorations positioned in 88 patients. Kaplan-Meier survival probability estimates were computed for failures (needed the replacement or removal of the prosthesis) and complications (resolved without replacing the prosthesis). RESULTS: One hundred and fifty single crowns (130 tooth-supported, 20 implant-supported) and 153 multiple units up to 6 elements (49 tooth-supported, 104 implant-supported) were followed-up for 7 years in 88 patients (40 men, 48 women), aged 35-89 years (mean 57). During the follow-up period, there were no complications for 287 (95 %) of the restorations. Sixteen restorations/abutment teeth (5 %) had some complication: extraction of abutment tooth (7, 2 %); caries (2, 1 %), porcelain veneer fracture (3, 1 %), loss of retention (4, 1 %). Nine (3 %) restorations were recorded as failures. The overall 7-year survival probability estimate for failures was 0.966 (95 % confidence limits, 0.932 and 0.983), for complications was 0.976 (95 % confidence limits 0.947 and 0.989), with a cumulative survival rate of 94.7 %. CONCLUSIONS: Within the analyzed follow-up, zirconia core restorations appear a good clinical solution, with favorable functional properties. CLINICAL RELEVANCE: All ceramic restorations can be successfully used for both single-and multiple-unit prostheses, either teeth or implants supported.

Abnormal Variations in the Facial Soft Tissues of Individuals With Down Syndrome: Sudan Versus Italy.

OBJECTIVE: To provide quantitative information about the facial soft tissue of Italian and Northern Sudanese subjects with Down syndrome by using summary anthropometric measurements. DESIGN, SETTING, AND PATIENTS: The three-dimensional coordinates of soft tissue facial landmarks were obtained using a computerized digitizer in 54 Italian subjects with Down syndrome (20 females and 34 males, 13 to 52 years), in 64 Northern Sudanese subjects with Down syndrome (18 females and 46 males, 5 to 34 years), and in 578 Italian and 653 Northern Sudanese reference subjects, matched for sex and age. From the landmarks, 16 facial dimensions were calculated. Data from subjects with Down syndrome were compared with those collected from control individuals by computing z scores. Two summary anthropometric measurements for quantifying craniofacial variations were obtained: the mean z score (an index of overall facial size) and its standard deviation, the craniofacial variability index (an index of facial harmony). RESULTS: In subjects with Down syndrome, facial size was significantly smaller and craniofacial variability was significantly greater than in typically developed individuals; 93% of Italian and 81% of Northern Sudanese subjects with Down syndrome had one or both values outside the normal interval. Overall, Italian subjects with Down syndrome differed more from the norm than did those from Northern Sudan. In the Northern Sudanese subjects, the mean z scores and the craniofacial variability index were significantly influenced by age: Older Northern Sudanese subjects with Down syndrome had smaller mean z scores and craniofacial variability index values than younger subjects. CONCLUSIONS: The two ethnic groups had different alterations in their soft tissue facial dimensions that were partially influenced by age.

Cellulose Nanocrystals Show Anti-Adherent and Anti-Biofilm Properties against Oral Microorganisms.

Cellulose nanocrystals (CNCs) are cellulose-derived nanomaterials that can be easily obtained, e.g., from vegetable waste produced by circular economies. They show promising antimicrobial activity and an absence of side effects and toxicity. This study investigated the ability of CNCs to reduce microbial adherence and biofilm formation using in vitro microbiological models reproducing the oral environment. Microbial adherence by microbial strains of oral interest, Streptococcus mutans and Candida albicans, was evaluated on the surfaces of salivary pellicle-coated enamel disks in the presence of different aqueous solutions of CNCs. The anti-biofilm activity of the same CNC solutions was tested against S. mutans and an oral microcosm model based on mixed plaque inoculum using a continuous-flow bioreactor. Results showed the excellent anti-adherent activity of the CNCs against the tested strains from the lowest concentration tested (0.032 wt. %, p < 0.001). Such activity was significantly higher against S. mutans than against C. albicans (p < 0.01), suggesting a selective anti-adherent activity against pathogenic strains. At the same time, there was a minimal, albeit significant, anti-biofilm activity (0.5 and 4 wt. % CNC solution for S. mutans and oral microcosm, respectively, p = 0.01). This makes CNCs particularly interesting as anticaries agents, encouraging their use in the oral field.

Salivary biomarkers: novel noninvasive tools to diagnose chronic inflammation.

Several chronic disorders including type 2 diabetes (T2D), obesity, heart disease and cancer are preceded by a state of chronic low-grade inflammation. Biomarkers for the early assessment of chronic disorders encompass acute phase proteins (APP), cytokines and chemokines, pro-inflammatory enzymes, lipids and oxidative stress mediators. These substances enter saliva through the blood flow and, in some cases, there is a close relation between their salivary and serum concentration. Saliva can be easily collected and stored with non-invasive and cost-saving procedures, and it is emerging the concept to use it for the detection of inflammatory biomarkers. To this purpose, the present review aims to discuss the advantages and challenges of using standard and cutting-edge techniques to discover salivary biomarkers which may be used in diagnosis/therapy of several chronic diseases with inflammatory consequences with the pursuit to possibly replace conventional paths with detectable soluble mediators in saliva. Specifically, the review describes the procedures used for saliva collection, the standard approaches for the measurement of salivary biomarkers and the novel methodological strategies such as biosensors to improve the quality of care for chronically affected patients.

Soft tissue facial morphometry before and after total oral rehabilitation with implant-supported prostheses.

The objective of the current study was to assess a low-cost, noninvasive facial morphometric digitizer to assist the practitioner in three-dimensional soft-tissue changes before and after oral rehabilitation. Twenty-two patients aged 45 to 82 years, all with edentulous maxilla and mandible, were assessed both before and after receiving their definitive complete implant-supported prostheses (each received 4-11 implants in each dental arch; full-arch fixed prostheses were made). The three-dimensional coordinates of 50 soft-tissue facial landmarks were collected with a noninvasive digitizer; labial and facial areas, volumes, angles, and distances were compared without and with the prostheses. Dental prostheses induced significant reductions in the nasolabial, mentolabial, and interlabial angles, with increased labial prominence (P < 0.05, Wilcoxon test). Lip vermilion area and volume significantly increased; significant increments were found in the vertical and anteroposterior labial dimensions. The presence of the dental prostheses significantly (P < 0.001) modified the three-dimensional positions of several soft-tissue facial landmarks. In conclusion, the current approach enabled quantitative evaluation of the final soft-tissue results of oral rehabilitation with implant-supported prostheses, without submitting the patients to invasive procedures. The method could assess the three-dimensional appearance of the facial soft tissues of the patient while planning the provisional prosthetic restoration, providing quantitative information to prepare the best definitive prosthesis.

Treatment for TMD with occlusal splint and electromyographic control: application of the FARC protocol in a Brazilian population.

The purpose of this study was to apply Functional Anatomy Research Center (FARC) Protocol of TMD treatment, which includes the use of a specific type of mandibular occlusal splint, adjusted based on the electromyographic index, in a group of 15 patients with disc displacement, classified according to the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) and then analyzing the results compared with the control group. The clinical evaluations were completed both before and after the treatment. Electromyographic (EMG) data was collected and recorded on the day the splint was inserted (visit 1), after one week (visit 2) and after five weeks of treatment (visit 3). The control group consisted of 15 asymptomatic subjects, according to the same diagnostic criteria (RDC/TMD), who were submitted to the same evaluations with the same interval periods as the treatment group. Immediately after splint adjustment, masseter muscle symmetry and total muscular activity were significantly different with than without the splint (p < 0.05), showing an increased neuromuscular coordination. After treatment, significant variations (p < .05) were found in mouth opening and in pain remission. There were no significant differences among the three sessions, either with or without the splint. There were significant differences between the TMD and control groups for all analyzed indices of muscular symmetry, activity and torque, with the exception of total muscular activity. The use of the splint promoted balance of the EMG activities during its use, relieving symptoms. EMG parameters identified neuromuscular imbalance, and allowed an objective analysis of different phases of TMD treatment, differentiating individuals with TMD from the asymptomatic subjects.

In vitro studies evaluating the efficacy of mouth rinses on Sars-Cov-2: A systematic review.

This systematic review aims to evaluate the evidence on the efficacy of mouth rinses on SARS-CoV-2 from in vitro studies. Five electronic databases were searched up to February 2021; no language or time restrictions were used. Two independent reviewers conducted both selection and data extraction processes. The toxicological data reliability assessment tool was used to evaluate the risk of bias. Starting from 239 articles, retrieved by the electronic search, only eight studies were included in our systematic review. Povidone Iodine (PVP-I) was effective in killing SARS-CoV-2, demonstrated higher virucidal activity than other commonly used active ingredients. Conflicting results were found about the effectiveness of Chlorhexidine (CHX) while hydrogen peroxide (H2O2) proved less effective than PVP-I. Other active ingredients, such as quaternary ammonium compounds and Ethanol (particularly when combined with essential oils), have also shown promising results in reducing viral load, with results comparable to PVP-I.

Direct 3D Printing of Clear Orthodontic Aligners: Current State and Future Possibilities.

The recent introduction of three-dimensional (3D) printing is revolutionizing dentistry and is even being applied to orthodontic treatment of malocclusion. Clear, personalized, removable aligners are a suitable alternative to conventional orthodontic appliances, offering a more comfortable and efficient solution for patients. Including improved oral hygiene and aesthetics during treatment. Contemporarily, clear aligners are produced by a thermoforming process using various types of thermoplastic materials. The thermoforming procedure alters the properties of the material, and the intraoral environment further modifies the properties of a clear aligner, affecting overall performance of the material. Direct 3D printing offers the creation of highly precise clear aligners with soft edges, digitally designed and identically reproduced for an entire set of treatment aligners; offering a better fit, higher efficacy, and reproducibility. Despite the known benefits of 3D printing and the popularity of its dental applications, very limited technical and clinical data are available in the literature about directly printed clear aligners. The present article discusses the advantages of 3D printed aligners in comparison to thermoformed ones, describes the current state of the art, including a discussion of the possible road blocks that exist such as a current lack of approved and marketed materials and limited existence of aligner specific software. The present review suggests the suitability of 3D direct printed aligners is superior to that of thermoformed manufactured aligners because of the prior's increased accuracy, load resistance, and lower deformation. It is an overall more stable way to produce an aligner where submillimeter movements can make a difference in treatment outcome. Direct 3D printing represents a complex method to control the thickness of the aligner and therefore has a better ability to control the force vectors that are used to produce tooth movement. There is currently no other approved material on the market that can do this. The conclusion of this article is that we encourage further in vitro and in vivo studies to test these new technologies and materials.

Activities of masticatory muscles in patients before orthognathic surgery.

AIM: To compare the influence of occlusal versus craniofacial characteristics on the functionality of the stomatognathic apparatus. MATERIALS AND METHODS: Two groups of subjects were selected: 27 patients (13 women and 14 men), 18 to 42 years old, all candidates for orthognathic surgery, 7 with prognathic syndrome and 20 with progenic syndrome; and 26 healthy young adults (13 women and 13 men) of corresponding age (control group). To verify the neuromuscular equilibrium induced by occlusion, the electromyographic activities of both right and left masseter and anterior temporal muscles were recorded and analyzed, calculating the percentage overlapping coefficient (an index of the symmetric distribution of the muscular activity determined by the occlusion) and TORS (index of the presence of mandibular torque). Data were compared with Student t-test for independent samples. RESULTS: Between the 2 groups of patients, no statistically significant differences were found, whereas the statistical analysis showed differences between patients and control subjects (P < 0.05): overall, the control subjects had a better neuromuscular stability than the patients who were candidates for orthognathic surgery. CONCLUSIONS: The electromyographic evaluations revealed that there was a neuromuscular imbalance determined by an occlusal instability in the patients candidates for orthognathic surgery, thus indicating that occlusion plays a more important role than any possible mechanical disadvantages due to altered craniofacial morphology.

A Call for Action to Safely Deliver Oral Health Care during and Post COVID-19 Pandemic.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) outbreak started just a couple of months ago and it grew rapidly causing several deaths and morbidities. The mechanism behind the transmission of the virus is still not completely understood despite a multitude of new specific manuscripts being published daily. This article highlights the oral cavity as a possible viral transmission route into the body via the Angiotensin converting enzyme 2 receptor. It also provides guidelines for routine protective measures in the dental office while delivering oral health care.

Adverse events associated with home use of mouthrinses: a systematic review.

BACKGROUND: Poor oral hygiene is strongly associated with oral and systemic diseases. Alongside mechanical tooth cleaning, the adjunctive use of mouthrinses has been widely advocated. Although research on the efficacy of various mouthrinse formulations is very active, there are a lack of conclusive data regarding their adverse effects. METHODS: We undertook a systematic review in accordance wih PRISMA guidelines of electronic databases of clinical trials of any duration with daily home use of mouthwashes, presenting clinical and subjective side effects (PROSPERO registration: CRD42016054037). RESULTS: After evaluating 614 titles and abstracts, 154 studies were selected for full-text analysis; 85 final papers were included. Based on the active ingredient in the test product, nine categories were created: cetyl pyridinium chloride, essential oils, chlorhexidine, triclosan, natural products, diclofenac, fluorides, delmopinol, and miscellaneous active substances. Most of the studies were of short duration (less than 6 months) with a defective 'methods' description; the reporting of adverse events often being overlooked. Both local morphological (oral mucosa and dental-crown staining, mucosal lesions) and functional (taste modifications, abnormal oral sensation) alterations were reported. Tooth staining was the most commonly listed adverse event, but it was quantitatively assessed only in a very small number of papers; most studies relied on patient reports. Staining was time associated; the longer the study, the higher its reported incidence and severity. CONCLUSIONS: The reduced report of side effects may partly be due to a lack of an objective measure and lack of general guidelines that demand studies report their adverse events. The most frequently reported adverse effect was teeth staining. As in most studies, the effect was associated with trial duration; clinical trials should be of sufficient duration. New investigations meeting the suggested criteria of a minimal duration of 6 months should be planned.

Electromyographic analysis of masticatory and neck muscles in subjects with natural dentition, teeth-supported and implant-supported prostheses.

OBJECTIVES: To compare the electromyographic (EMG) characteristics of masticatory and neck muscles in patients with natural dentition, teeth-supported prostheses and implant-supported prostheses. MATERIALS AND METHODS: Twenty-five subjects aged 40-80 years were examined. Five patients had maxillary and mandibular implant-supported fixed prostheses; five patients had mandibular implant-supported fixed prosthesis and maxillary removable complete denture; seven patients had implant-supported fixed prosthesis (one arch) and natural dentition or full-arch tooth-fixed prosthesis (one arch); and eight control subjects had natural dentition or single tooth-fixed prostheses. Surface EMG of masseter, temporal and sternocleidomastoid muscles was performed during maximum teeth clenching and unilateral gum chewing. Interarch dental contacts were assessed with shim stocks. RESULTS: All groups had similar interarch dental contacts (P>0.05). During clenching, patients with maxillary and mandibular implant-supported fixed prostheses had unbalanced standardized masseter and temporalis anterior activities (74%), with significantly larger values found in the other patients and control subjects (all mean values larger than 86%, P=0.017). All patients chewed with significantly larger muscular potentials than control subjects (on average, 1434-2100 microV s vs. 980 microV s, P=0.04), and had altered muscular patterns (left side, P=0.021). The patients with one arch with natural dentition/tooth fixed prostheses had chewing muscular patterns similar to the control subjects. CONCLUSIONS: Clenching with the analyzed prostheses was performed with a relative increment of temporalis activity. Neuromuscular coordination during chewing was larger in patients who maintained their teeth or dental roots, independently from the number of dental contacts.

Three-dimensional facial morphometry of attractive Italian women.

OBJECTIVES: To identify reference standards and possible esthetic features in facial proportion and form of Italian adult women. METHODS AND SUBJECTS: A three-dimensional electromagnetic digitizer was used to collect the coordinates of 50 facial landmarks (forehead, eyes, nose, cheeks, mouth, jaw, ears) in 71 healthy, reference women (18-30 years old) and in 48 "attractive" women selected during a beauty competition; soft tissue facial angles, distances and volumes were computed. RESULTS: Attractive women had wider faces with a relatively larger upper facial third (forehead); a larger facial width relative to facial height. The mouth was larger, and lips were more prominent; the interlabial angle was reduced. Overall, the soft-tissue profile was more prominent, with a larger maxillary prominence relative to the mandible. Faces in the attractive women were more flat in the horizontal plane. For several of the analyzed measurements, similar patterns were observed for the 36 women participants to the semi-final stage of the beauty competition, the 12 finalists, and the winner. The winner of the beauty competition deviated from the reference women more than the other two groups of attractive women. CONCLUSION: Esthetic reference values were determined for a population of 18-30 year olds that reflect contemporary society.

Implant rehabilitation in fibula-free flap reconstruction: A retrospective study of cases at 1-18 years following surgery.

PURPOSE: To determine the dental implant and prostheses success rate in a cohort of patients who underwent a vascularized fibula-free flap (FFF) for maxillary or mandibular reconstruction. METHODS: The investigators implemented a retrospective cohort study composed of patients who had undergone primary or secondary FFF reconstruction jaw surgery plus placement of 2-6 implants in the reconstructed arch, which were restored with an implant-supported prosthesis. The sample was composed of all patients who underwent FFF surgery between 1998 and 2012 and had either simultaneous or secondary dental implant placement. A total of 28 patients met inclusion criteria. Of these, 22 patients participated in the retrospective review. Patients were examined by an independent observer between January-December 2015. In addition, all patients completed a questionnaire to access satisfaction with the implant-supported prosthesis. RESULTS: The patient cohort consisted of 12 males and 10 females, age 12-70 years. A total of 100 implants were placed, 92 implants in fibular bone and 8 implants in native bone. In the maxilla, 35 implants were placed into fibular bone and 4 into native bone (11 in irradiated patients and 28 in non-irradiated patients). In the mandible, 57 implants were placed into fibular bone and 4 into native bone (15 in irradiated patients and 46 in non-irradiated patients). The mean follow-up after implant loading was 7.8 years (range 1.3-17.5 years). The implant survival rate was 98% (95% CI: 92.2%-99.5%). No statistically significant difference was found in implant success between maxillary and mandibular implants, or between radiated and non-radiated bone. The prostheses success rate, determined by clinical exam and patient satisfaction, was 100%. CONCLUSION: The results of this study suggest that implant survival is high and implant-supported prostheses are a reliable rehabilitation option in patients whose jaws have been reconstruction with a FFF.

Effects of the functional orthopaedic therapy on masticatory muscles activity.

BACKGROUND: The purpose of this study was to examine surface electromyographic (sEMG) activity of masticatory muscles before and after functional orthopaedic therapy with Sander appliance. MATERIAL AND METHODS: Ten adolescents (5 girls, 5 boys) with an Angle Class II, division I malocclusion, 9-13 years old, were submitted to sEMG before and after functional orthopaedic therapy. To verify the neuromuscular equilibrium, the standardized EMG activities of right and left masseter and anterior temporal muscles were recorded during maximum voluntary clench, and analysed calculating: POC (index of the symmetric distribution of the muscular activity determined by the occlusion); TC (index of presence of mandibular torque) and Ac (index suggesting the position of occlusal barycentre). The total muscular activity was also calculated. Pre- and post- functional therapy data were compared with Wilcoxon Signed-Rank Test. RESULTS: Before treatment, all subjects had a good neuromuscular equilibrium, which was not altered by treatment. CONCLUSIONS: sEMG evaluations allow to quantify the impact of occlusion on masticatory muscle activity and to control that the functional orthopaedic therapy maintain a good muscular coordination. Key words:Functional appliance, Sander appliance, electromyography, masticatory muscles.

Longitudinal effects of rapid maxillary expansion on masticatory muscles activity.

BACKGROUND: To investigate the modifications induced by rapid maxillary expansion (RME) on the electromyographic (EMG) activities of the anterior temporal and superficial masseter muscles, in patients without pre-treatment EMG alterations. MATERIAL AND METHODS: Twenty-one patients with unilateral posterior cross-bite selected from the orthodontic department of the University of L'Aquila (Italy), were enrolled. There was no control group in this study since each subject acted as a control of her/himself. Two surface EMG recordings were taken: T0 (before RME) and at T1 (3 month after the end of expansion). To verify the neuromuscular equilibrium, the EMG activities of both right and left masseter and anterior temporal muscles were recorded during a test of maximum clench. EMG indexes were compared by paired Student's t-test. RESULTS: In both occasions, all indices showed a good symmetry between the right and left side masticatory muscles. No statistically significant differences were found between the two recordings. CONCLUSIONS: In children without pre-treatment EMG alterations, no variations in standardized muscular activity after RME were found. The treatment did not alter the equilibrium of the masseter and temporal muscles. Key words:Rapid maxillary expansion, electromyography, masticatory muscles.