Relationship between oral microbiota and colorectal cancer: A systematic review.

This systematic review aims to investigate the microbial basis underlying the association between oral microbiota and colorectal cancer. A comprehensive search was conducted across four databases, encompassing potentially relevant studies published up to April 2024 related to the PECO question: "Is there a differentiation in oral microbial composition between adult patients diagnosed with colorectal cancer compared to healthy patients?". The Newcastle-Ottawa Scale was used to evaluate the quality of the studies included. The level of evidence was assessed through the GRADE (Grading of Recommendations, Assessment, Development and Evaluation) tool. Sixteen studies fulfilled the eligibility criteria. Based on low to moderate evidence profile, high levels of certain subspecies within Firmicutes (such as Streptococcus anginosus, Peptostreptococcus stomatis, S. koreensis, and S. gallolyticus), Prevotella intermedia, Fusobacterium nucleatum, and Neisseria oralis were found to be associated with colorectal cancer. Conversely, certain bacteria (e.g., Lachnospiraceae, F. periodonticum, and P. melaninogenica) could exert a symbiotic protective effect against colorectal cancer. Based on existing evidence, it appears that variations in oral microbiota composition exist among individuals with and without colorectal cancer. However, further research is necessary to determine the mechanisms of oral dysbiosis in colorectal carcinogenesis.

Relationship of ankyloglossia and obstructive sleep apnea: systematic review and meta-analysis.

PURPOSE: Recent studies have highlighted the potential role of a short lingual frenulum as a risk factor for pediatric obstructive sleep apnea syndrome. A shortened frenulum may contribute to abnormal orofacial development, leading to increased upper airway resistance and susceptibility to upper airway collapsibility during sleep. Recognizing early indicators, such as a short lingual frenulum, is crucial for prompt intervention. This systematic review aims to evaluate the association between a short lingual frenulum and the risk of obstructive sleep apnea syndrome in children. METHODS: This systematic review adheres to PRISMA criteria for a quantitative analysis. A comprehensive search was conducted on five databases until January 2024 to identify relevant studies. The selected articles underwent rigorous analysis, considering study design, sample characteristics, lingual frenulum characterization, sleep assessment methods, and key findings. RESULTS: A total of 239 references were initially identified. Finally, six studies were included in the qualitative synthesis, with four studies eligible for the quantitative synthesis. The Newcastle-Ottawa scale was employed to assess study quality. Meta-analysis, supported by a moderate evidence profile according to the GRADE scale, revealed statistically significant differences, with odds ratios of 3.051 (confidence interval: 1.939 to 4.801) for a short frenulum and 12.304 (confidence interval: 6.141 to 24.653) for a high-arched palate. CONCLUSION: This systematic review and meta-analysis provide evidence supporting the association between ankyloglossia and obstructive sleep apnea in children. Nevertheless, it is crucial to consider additional factors such as tongue mobility and the presence of a high-arched palate in further evaluations.

Polysomnographic phenotypes: predictors of treatment response in Obstructive Sleep Apnea with Mandibular Advancement devices.

PURPOSE: This non-randomized clinical study aims to identify polysomnographic phenotypic characteristics that differentiate responders from non-responders to mandibular advancement devices (MAD) treatment for obstructive sleep apnea (OSA) and to establish a predictive model of treatment response for OSA using oral devices based on the set of anthropometric, demographic, and polysomnographic phenotypic characteristics. METHODS: This study was registered under the identifier number: NCT02724865. It prospectively analyzed patients receiving MAD treatment for six years. The MADs used were two-piece adjustable appliances following a standardized protocol. Treatment response was defined according to the latest International Consensus Statement on OSA severity. The study analyzed polysomnographic phenotypes, categorizing them into positional phenotype, sleep-stage phenotype (REM/NREM-OSA), and airway collapsibility phenotype. A logistic regression model and a classification and regression tree were implemented. RESULTS: A total of 112 patients completed the study (64 responders and 48 non-responders). Positional-OSA patients had higher response rates than non-positional (64.1% vs. 35.9; p 0.032). REM-OSA and apnea-predominant phenotype showed a lower response (p < 0.001). In these phenotypes, most patients were women, with higher body mass index, higher scores in the Epworth Sleepiness Scale, lower minSaO2 in REM-OSA phenotype, and higher T90% in apnea-predominant phenotype. CONCLUSION: This study underscores the importance of hypoxic burden in the severity of OSA. The parameters T90% and POSA formed predictive model. Additionally, MAD appears to be less effective in the REM-OSA phenotype. Moreover, although patients with an apnea-predominant phenotype responded less favorably, there was a conversion from apneas to hypopneas, reducing severity.

Perception, attitude, and opinion of parents of cleft lip and palate patients treated with nasoalveolar molding (NAM): A cross-sectional questionnaire study.

BACKGROUND: The main goal of the nasoalveolar molding (NAM) is to mitigate the initial severity of the cleft, facilitating the subsequent surgical procedures. Nevertheless, the use of the appliance entails high stress levels for families. AIM: The aim of this study was to assess the perceptions, attitudes, and opinions of parents whose cleft-affected children underwent treatment using the NAM technique. DESIGN: A cross-sectional questionnaire study was conducted on a cohort of relatives of infants born with cleft lip and palate who were treated with the NAM appliance. The parents completed a 59-item questionnaire that had been previously validated. RESULTS: The initial cohort consisted of 104 families. The level of satisfaction was high, and there was a direct correlation with early diagnosis. Satisfaction levels varied depending on the cleft type, with a decrease in cases of bilateral presentation. Satisfaction was influenced by the newborns' adaptation and the absence of complications. Parents who exhibited lower levels of satisfaction contemplated terminating the treatment. CONCLUSIONS: Parents expressed high satisfaction with NAM treatment, due to effective management and understanding. Bilateral clefts and delayed diagnosis can significantly impact satisfaction. These results emphasize the importance of personalized approaches to address challenges in NAM treatment, particularly in instances of bilateral clefts and delayed diagnoses.

Skin temperature measurement in individuals with spinal cord injury during and after exercise: Systematic review.

BACKGROUND: Athletes with spinal cord injury (SCI) have difficulties in maintaining thermal homeostasis during exercise due to their lower sweat capacity and skin vasodilation. Skin temperature (Tsk) assessment, as opposed to core temperature, has become more widely accepted due to its non-invasive nature. The aims of this systematic review was to collate research studies that measured Tsk of individuals with SCI during or after exercise, study their Tsk response, taking into account the method employed, the environmental and exercise conditions, and to identify the different cooling strategies and their effect during exercise. METHODS: Pubmed, Web of Science and Scopus databases were searched to identify the articles published since year 2000. Two reviewers working independently extracted data and assessed the quality of the articles included. If they disagreed, a third reviewer was consulted. ROBINS-I scale was used to assess the quality of the articles, and the review has been conducted in agreement with PRISMA guidelines. RESULTS: Twenty studies were included in this review. 84% of them presented moderate, serious or critical risk of bias. The entire of the studies assessed Tsk during exercise, but only seven studies measured it during rest or after exercise. Eighteen studies used contact thermometry to assess Tsk and the two remaining studies employed non-contact techniques. Seven studies were conducted in warm conditions (>31.5°C) and the remaining studies in moderate conditions (10°C to 26.6°C). According to cooling strategies, ice vests and water spray are effective in reducing Tsk and decreasing the risk of heat stroke. CONCLUSIONS: The 90% of the studies applied contact thermometry and due to their effect in the data assessed, it is necessary more research into the SCI population using infrared thermography due to its differences in characteristics, methodology, and applications. The methodological differences among studies make difficult to perform a meta-analysis.

Unplanned molar intrusion after Invisalign treatment.

INTRODUCTION: The objectives of this study were to analyze and quantify molar intrusion after the use of clear aligners and to analyze the relationship with other variables such as age, duration of treatment, and a series of cephalometric osseous and dental measurements at the start of treatment. METHODS: A retrospective descriptive-analytical study was designed with a sample of 58 patients aged 18-60 years who had undergone treatment with Invisalign. The cephalometric measurements were carried out after lateral x-rays were taken of the cranium; these were compared at the start (T0) and conclusion of treatment. Parametric and nonparametric tests were used to compare means, whereas Pearson correlations and multivariate lineal regression analyses were used to establish the variables associated with molar intrusion. RESULTS: Approximately 74.2% of the patients presented some degree of molar intrusion after treatment. Furthermore, 32.8% of patients presented intrusion only at the mandibular molar, whereas 25.9% experienced intrusion at both molars, maxillary and mandibular, simultaneously. However, 15.5% presented intrusion only at the maxillary molar. The average magnitude of intrusion here was 0.98 ± 0.54 mm, whereas the mandibular molar was 0.84 ± 0.29 mm. Statistically significant reductions exist for the distance L6_MP and U6_SN between T0 and at conclusion of treatment. Maxillary molar intrusion correlates negatively with mandibular molar intrusion (r = -0.270). The number of days of treatment did not correlate with either maxillary or mandibular molar intrusion. CONCLUSIONS: Clear aligners give rise to molar intrusion in 74.2% of patients. The cephalometric variables L6_MP T0, mandibular plane angle T0, and facial axis T0 were negatively and significantly associated with maxillary molar intrusion, whereas age and facial axis T0 were negatively associated with mandibular molar intrusion allowing smaller magnitudes of intrusion to be predicted when these variables present high values at T0.

Effectiveness of removable appliances with temperature sensors in orthodontic patients: a systematic review and meta-analysis.

BACKGROUND/OBJECTIVE: Patient compliance during orthodontic treatment is one of the factors that most affects success in the final result. The use of removable appliances is frequent at an early age and the monitoring of its use is essential to assess the collaboration of the patient. The aim of this study was to establish the effectiveness of microsensors included in removable appliances during orthodontic treatment or in the retention phase to enable a reliable and individualized follow-up of the patient. SEARCH METHODS: The article search was carried out in various electronic databases and journals without any language restrictions. SELECTION CRITERIA: Studies using microsensors into removable appliances were selected with the key selection criterion of a minimum follow-up of 4 weeks. DATA COLLECTION AND ANALYSIS: The quality of the studies included was evaluated using the Cochrane scale for the randomized controlled trials and the Newcastle Ottawa Scale for control-case, cohort, and transversal studies. The mean of the differences with a 95% confidence interval was expressed for the continuous data. RESULTS: Twenty-nine full-text articles were analysed and included in the qualitative synthesis. In general, the mean daily wear time of removable appliances measured objectively was less than the time that the professional had predetermined. CONCLUSIONS: The use of microsensors as an objective measurement method enhances communication and boosts confidence in the orthodontist-patient relationship. More random clinical studies with temperature sensors are needed to establish to what extent they influence the orthodontic outcome. REGISTRATION: PROSPERO (CRD42019120525).

Nonsurgical treatment of an adult with skeletal Class III malocclusion, anterior crossbite, and an impacted canine.

Class III malocclusion presents some complexity in terms of diagnosis and treatment and affects not only the jaws but the whole craniofacial complex. Besides, functional forward displacement of the mandible may be diagnosed in a patient presenting Class III malocclusion, as the 2 entities are not incompatible or mutually exclusive. This case report describes the multidisciplinary, nonsurgical, orthodontic treatment of an adult patient with a skeletal Class III malocclusion, anterior crossbite, and a palatally impacted canine, treated with fixed appliances and skeletal anchorage. To upright the mandibular molars, distalize the whole mandibular arch, and avoid excessive inclination of maxillary incisors to improve dentofacial esthetics, miniscrews were placed in the retromolar area. The treatment results were very satisfactory and remained stable after a reasonable retention period.

Miniscrew mechanics for molar distalization and incisor intrusion in a patient with a Class II brachyfacial pattern and gummy smile.

A gummy smile is one of the most problematic characteristics in patients with a Class II Division 2 malocclusion, and the correction of vertical position and incisor torque is often challenging for the orthodontist. This case report describes the orthodontic treatment of a 31-year-old woman, assisted by miniscrew mechanics for maxillary arch distalization and correction of a gummy smile with a brachyfacial pattern. Two different mechanics were used. Miniscrews were placed in both maxillary tuberosities, and the maxillary arch was successfully distalized, correcting the Class II relationship. Interradicular miniscrews were placed for maxillary and mandibular incisor intrusion to correct the gummy smile, overbite, and torque. Finally, periodontal surgery was performed to lengthen the maxillary incisor crowns. Satisfactory smile esthetics and good occlusion were achieved. Follow-up after 24 months confirmed that the outcome was stable.

Antibacterial Properties of Nanoparticles in Dental Restorative Materials. A Systematic Review and Meta-Analysis.

Background and Objectives: Nanotechnology has become a significant area of research focused mainly on increasing the antibacterial and mechanical properties of dental materials. The aim of the present systematic review and meta-analysis was to examine and quantitatively analyze the current evidence for the addition of different nanoparticles into dental restorative materials, to determine whether their incorporation increases the antibacterial/antimicrobial properties of the materials. Materials and Methods: A literature search was performed in the Pubmed, Scopus, and Embase databases, up to December 2018, following PRISMA (Preferred Reporting Items for Systematic Review and Meta-Analysis) guidelines for systematic reviews and meta-analyses. Results: A total of 624 papers were identified in the initial search. After screening the texts and applying inclusion criteria, only 11 of these were selected for quantitative analysis. The incorporation of nanoparticles led to a significant increase (p-value <0.01) in the antibacterial capacity of all the dental materials synthesized in comparison with control materials. Conclusions: The incorporation of nanoparticles into dental restorative materials was a favorable option; the antibacterial activity of nanoparticle-modified dental materials was significantly higher compared with the original unmodified materials, TiO2 nanoparticles providing the greatest benefits. However, the high heterogeneity among the articles reviewed points to the need for further research and the application of standardized research protocols.

Femtosecond laser settings for optimal bracket bonding to zirconia.

Bonding orthodontic brackets to ceramic materials is a challenging procedure; femtosecond (FS) laser conditioning could provide improved results, but the ideal settings for effective bracket-zirconia bonding have never been established. This study aimed to analyze the differences in surface roughness and shear bond strength (SBS) produced by different femtosecond laser settings and establish a protocol to prepare zirconia surfaces for optimal adhesion to metal orthodontic brackets. One hundred eighty zirconia samples were assigned to six groups according to surface treatment: (1) control; (2) air-particle abrasion (APA); (3) FS laser irradiation (300 mW output power, 60 µm inter-groove distance); (4) FS laser irradiation (200 mW, 100 µm); (5) FS laser irradiation (40 mW, 60 µm); and (6) FS laser irradiation (200 mW, 60 µm). Surface roughness was measured. Orthodontic brackets were bonded to the zirconia specimens, and SBS was measured. SBS in groups 3 and 6 was significantly higher than the other groups (5.92 ± 1.12 MPa and 5.68 ± 0.94 MPa). No significant differences were found between groups 1, 2, 4, and 5 (3.87 ± 0.77 MPa, 4.25 ± 0.51 MPa, 3.74 ± 0.10 MPa, and 3.91 ± 0.53 MPa). Surface roughness was significantly greater for FS laser than for control and APA groups (p = 1.28 × 10-8). FS laser at 200 mW, 60 µm can be recommended as the ideal settings for treating zirconia surfaces, producing good SBS and more economical energy use.

Current trends in orthodontic journals listed in Journal Citation Reports. A bibliometric study.

INTRODUCTION: The aim of this study is to analyze articles published in orthodontic journals included in Journal Citation Reports (JCR) to determine current trends in orthodontic publishing. METHODS: Articles included in orthodontic journals in 2016 JCR and published during 2007-2017 were selected. After applying inclusion criteria, author-based parameters (article title, first author's name, institution and sex, number of authors, number of affiliations, first author's origin, and geographic origin), article-based parameters (article type, main topic, and research design), and the number of cites and self-cites were registered for each article. RESULTS: A total of 7119 articles were analyzed, and 842 different centers and 4483 different authors were identified. The percentage of female authors showed a tendency to increase over the decade; the most productive country was the United States (17.4%). Bone anchorage was the most recurrent topic (7.2%). More than three-fourths of articles (80.8%) proceeded from orthodontic departments belonging to public institutions, with a decreasing trend in nonacademic or private affiliations. Positive and negative correlations were found to exist between citation counts and other variables. CONCLUSIONS: American Journal of Orthodontics and Dentofacial Orthopedics, Angle Orthodontist, and European Journal of Orthodontics were the 3 main journals with regard to production volume, with the United States being the most productive country. The most recurrent topic was bone anchorage, and most of the studies were research articles with observational cross-sectional design. Study design, geographic origin of the articles, article type, and the main subject of the article may be predictive of citation numbers.

Effect of 2% Chlorhexidine Following Acid Etching on Microtensile Bond Strength of Resin Restorations: A Meta-Analysis.

Background and Objectives: The aim of this systematic review was to examine the effect of 2% chlorhexidine following acid etching on the microtensile bond strength of resin restorations for different follow-up times. Materials and Methods: A thorough search of PubMed, Scopus, and Embase databases were conducted. In vitro experimental studies or in vivo studies published up to December 2018 with an experimental group treated with a 2% chlorhexidine solution following acid etching and a control group were included, wherein the final restoration used a resin composite in both the groups. Results: Twenty-one articles were identified for qualitative analysis and 18 for meta-analysis. The difference in the means of microtensile bond strength between the two groups was calculated for the different follow-up times. The differences were significant for 6 months (4.30 MPa; 95% CI 2.72-5.89), 12 months (8.41 MPa; 95% CI 4.93-11.88), and 2-5 years including aged and thermocycling samples (9.08 MPa; 95% CI 5.36-12.81). There were no significant differences for the type of adhesive used. A meta-regression model showed a significant effect of time on the microtensile bond strength. Conclusions: The application of a 2% chlorhexidine solution after acid etching increased the microtensile bond strength significantly for follow-up times of 6 months or more. The adhesive type had no influence.

Miniscrew-assisted multidisciplinary orthodontic treatment with surgical mandibular advancement and genioplasty in a brachyfacial Class II patient with mandibular asymmetry.

This article describes the complex dental treatment of a 43-year-old man with skeletal Class II, mandibular asymmetry, severe brachyfacial pattern, Class II Division 2, canting of the occlusal plane, and an increased curve of Spee. To achieve optimal results, we adopted a multidisciplinary approach to treatment, involving periodontics, oral surgery, orthodontics, maxillofacial surgery, and prosthetics specialists. After periodontal treatment, miniscrews were placed to correct the occlusal plane canting and the excessive curve of Spee with orthodontic treatment. The surgical treatment plan consisted of a bilateral asymmetric sagittal split osteotomy for mandibular advancement and genioplasty. The patient had an infection after the surgery at the site of the right fixation plate, so the plate was removed, and active orthodontic treatment was continued and finished. Mandibular first molar implants and maxillary ceramic crowns using the Digital Smile Design method (Digital Smile Design, Doral, FL) were placed at the end of orthodontic treatment. The patient was satisfied with the treatment results and with his facial and dental appearance, as well as his oral function. The 2-year follow-up pictures show a stable result both esthetically and functionally.

Orthodontic treatment need of 9, 12 and 15 year-old children according to the Index of Orthodontic Treatment Need and the Dental Aesthetic Index.

OBJECTIVE: To assess the differences in occlusal features in three cohorts at 9, 12 and 15 years of age, and compare orthodontic treatment need measured by the Dental Aesthetic Index (DAI) and Index of Orthodontic Treatment Need (IOTN). DESIGN: Cross-sectional study. SETTING: School of Dentistry, University of Valencia. SUBJECTS: A total of 1086 children: 321 aged 9, 397 aged 12 and 368 aged 15. METHODS: Children were examined to measure their orthodontic treatment need according to IOTN and DAI. The main outcome measure was orthodontic treatment need according to the DAI and IOTN indices. RESULTS: Overbite and inter-incisal diastema were the occlusal features that presented significant differences between the three groups, diminishing with age. Treatment need according to the IOTN was 15.4% at 9 years, 20.9% at 12 years and 12.8% at 15 years. Treatment need according to DAI was 44.8% at 9 years, 21.7% at 12 years and 14.1% at 15 years. The diagnostic agreement between the two indices on the treatment need by age group was very low at 9 years (Kappa 0.18) and moderate at 12 and 15 years (Kappa 0.451 and 0.405, respectively). CONCLUSIONS: Orthodontic treatment need is greater in the mixed dentition and falls slightly as the child grows. The greatest variation in results between 9 and 15 years were found in relation to the DAI, which is consequently not recommended for use in the mixed dentition.

Association between third molar agenesis and craniofacial structure development.

INTRODUCTION: The aim of this investigation was to study the relationship between third molar agenesis-including the number of ageneses-and craniofacial structure growth. METHODS: We reviewed 305 clinical histories of patients treated at the Orthodontics Unit of the Faculty of Medicine and Dentistry at the University of Valencia in Spain. This included radiographic records of optimal quality. Of these, 40 patients who had agenesis of at least 1 third molar were included in the study group. A control group was formed with another 40 patients with all 4 third molars present. For both groups, a further criterion for inclusion was cone-beam computed tomography records. The cephalometric analysis was performed with NemoCeph 3D software (version 11.3.1.38; Nemotec, Madrid, Spain). RESULTS: The only significant differences between the 2 groups were in the total gonial angle and the upper gonial angle (P ≤0.05), both of which were smaller in the study group. CONCLUSIONS: Third molar agenesis is associated with a reduction in Jarabak's gonial angle and upper gonial angle, characteristic of patients with a more horizontal or brachyfacial skeletal pattern. No significant differences were found in other measurements.

Esthetic Assessment of the Effect of Gingival Exposure in the Smile of Patients with Unilateral and Bilateral Maxillary Incisor Agenesis.

PURPOSE: The aim of this study was to determine the dental esthetic perception of the smile of patients with maxillary lateral incisor agenesis (MLIA); the perceptions were examined pre- and post-treatment. Esthetic determinations were made with regard to the gingival exposure in the patients' smile by orthodontists, general dentists, and laypersons. MATERIALS AND METHODS: Three hundred eighty one people (80 orthodontists, 181 general dentists, 120 laypersons) rated the attractiveness of the smile in four cases before and after treatment, comprising two cases with unilateral MLIA and contralateral microdontia and two with bilateral MLIA. For each case, the buccal photograph was adjusted using a computer to apply standard lips to create high, medium, and low smiles. A numeric scale was used to measure the esthetic rating perceived by the judges. The resulting arithmetic means were compared using an ANOVA test, a linear trend, and a Student's t-test, applying a significance level of p < 0.05. The predictive capability of the variables, unilateral, or bilateral MLIA, symmetry of the treatment, gingival exposure of the smile, group, and gender were assessed using a multivariable linear regression model. RESULTS: In the pre- and post-treatment cases, medium smile photographs received higher scores than the same cases with high or low smiles, with significant differences between them. In all cases, orthodontists were the least-tolerant evaluation group (assigning lowest scores), followed by general dentists. In a predictive linear regression model, bilateral MLIA was the more predictive variable in pretreatment cases. The gingival exposure of the smile was a predictive variable in post-treatment cases only. CONCLUSION: The medium-height smile was considered to be more attractive. In all cases, orthodontists gave the lowest scores, followed by general dentists. Laypersons and male evaluators gave the highest scores. Symmetrical treatments scored higher than asymmetrical treatments. The gingival exposure had a significant influence on the esthetic perception of smiles in post-treatment cases.

Cross-sectional study of malocclusion in Spanish children.

OBJECTIVES: This study was conducted to determine the orthodontic treatment need of the child population of the Valencia region of Spain, employing the DAI and the IOTN, to examine the relations between treatment need, socio-economic data and gender and to assess the diagnostic agreement between the two indices. STUDY DESIGN: A cross-sectional descriptive study was conducted in a random representative sample of the schoolchild population of the Valencia region of Spain. The sample size was a total of 765 children aged 12 and 15 years at 39 schools. RESULTS: The orthodontic treatment need assessed by the DAI was 21.7% at 12 years of age and 14.1% at 15 years. The orthodontic treatment need assessed by the IOTN DHC was 20.9% at 12 years of age and 12.7% at 15 years. The diagnostic agreement between the DAI and the modified IOTN was moderate, with Kappa scores of 0.426 at 12 years of age and 0.415 for the 15-year-old group. CONCLUSIONS: Approximately 20% of the children needed orthodontic treatment. Neither gender nor social class appeared to exert a significant influence on orthodontic treatment need.

Biological significance of long-term bisphenol A release in the saliva of patients wearing orthodontic appliances: A systematic review and meta-analysis.

Background: Orthodontic appliances contain Bisphenol A and are controversial due to its potential risks for human health. Thus, the aim of the present research was to identify the presence of Bisphenol A in the saliva of patients wearing orthodontic appliances. Material and Methods: A systematic search of the literature was conducted in four electronic databases (PubMed, Embase, Scopus, and Web of Science) and a manual search of grey literature. Research was done up to March 2023, without language restrictions. Based on inclusion/exclusion criteria, data were extracted by two independent reviewers. Results: A total of 2293 potentially eligible articles were identified, of which 8 were finally included. The studies included a total of 238 patients and showed a moderate quality in the PEDro scale. All the devices studied released Bisphenol A into the saliva, with the polycarbonate brackets being the ones that released it for a longer time. The most significant increase occurred in the first 30 minutes after bonding with composites, reaching 697 µg/g. with polycarbonate brackets. Conclusions: Although a statistically significant increase of Bisphenol A levels in the saliva of orthodontic patients were found, this increase does not exceed the maximum allowable daily intake. Thus, the use of these materials can be considered safe for human health. Key words:BPA, Bisphenol-A, cytotoxicity, Orthodontic materials, Composite resins.

Validation of the psychosocial impact of dental aesthetics questionnaire (Pidaq) in Spanish adolescents.

OBJECTIVES: The purpose of this study was to assess the validity and reliability of the Spanish version of PIDAQ for application in adolescents. STUDY DESIGN: The questionnaire was translated, cross-culturally adapted and completed by 627 adolescents (366 12-year-olds and 261 15-year-olds). The adolescents were also examined by 4 examiners who had been calibrated against a gold standard and relative to each other (Kappa >0.85) in determining treatment need with the Dental Aesthetic Index (DAI) and the Index of Orthodontic Treatment Need (IOTN) DHC and AC components. RESULTS: Cronbach's alpha of the translated PIDAQ was 0.90. The 23 items of the questionnaire were divided into four domains that explained 60% of the variance. The test-retest reliability of the questionnaire was 0.93. Discriminant validity revealed a significant association between the scores for the questionnaire and its subscales or domains and those for the DAI, IOTN-DHC and IOTN-AC treatment need indices. Adolescents with orthodontic treatment need scored higher in the questionnaires. CONCLUSIONS: The results show that the Spanish version of PIDAQ has a very similar internal structure and psychometric properties to those of the original questionnaire and demonstrate its validity for use with Spanish adolescents.