Skeletal Class III phenotype: Link between animal models and human genetics: A scoping review.

This study aimed to identify evidence from animal studies examining genetic variants underlying maxillomandibular discrepancies resulting in a skeletal Class III (SCIII) malocclusion phenotype. Following the Manual for Evidence Synthesis of the JBI and the PRISMA extension for scoping reviews, a participant, concept, context question was formulated and systematic searches were executed in the PubMed, Scopus, WOS, Scielo, Open Gray, and Mednar databases. Of the 779 identified studies, 13 met the selection criteria and were included in the data extraction. The SCIII malocclusion phenotype was described as mandibular prognathism in the Danio rerio, Dicentrarchus labrax, and Equus africanus asinus models; and as maxillary deficiency in the Felis silvestris catus, Canis familiaris, Salmo trutta, and Mus musculus models. The identified genetic variants highlight the significance of BMP and TGF-ß signaling. Their regulatory pathways and genetic interactions link them to cellular bone regulation events, particularly ossification regulation of postnatal cranial synchondroses. In conclusion, twenty genetic variants associated with the skeletal SCIII malocclusion phenotype were identified in animal models. Their interactions and regulatory pathways corroborate the role of these variants in bone growth, differentiation events, and ossification regulation of postnatal cranial synchondroses.

Craniofacial syndromes and class III phenotype: common genotype fingerprints? A scoping review and meta-analysis.

Skeletal Class III (SCIII) is among the most challenging craniofacial dysmorphologies to treat. There is, however, a knowledge gap regarding which syndromes share this clinical phenotype. The aims of this study were to: (i) identify the syndromes affected by the SCIII phenotype; (ii) clarify the involvement of maxillary and/or mandibular structures; (iii) explore shared genetic/molecular mechanisms. A two-step strategy was designed: [Step#1] OMIM, MHDD, HPO, GeneReviews and MedGen databases were explored; [Step#2]: Syndromic conditions indexed in [Step#1] were explored in Medline, Pubmed, Scopus, Cochrane Library, WOS and OpenGrey. Eligibility criteria were defined. Individual studies were assessed for risk of bias using the New Ottawa Scale. For quantitative analysis, a meta-analysis was conducted. This scoping review is a hypothesis-generating research. Twenty-two studies met the eligibility criteria. Eight syndromes affected by the SCIII were targeted: Apert syndrome, Crouzon syndrome, achondroplasia, X-linked hypohidrotic ectodermal dysplasia (XLED), tricho-dento-osseous syndrome, cleidocranial dysplasia, Klinefelter and Down syndromes. Despite heterogeneity between studies [p < 0.05], overall effects showed that midface components were affected in Apert and Down Syndromes, lower face in Klinefelter Syndrome and midface and lower face components in XLED. Our review provides new evidence on the craniofacial characteristics of genetically confirmed syndromes exhibiting the SCIII phenotype. Four major regulatory pathways might have a modulatory effect on this phenotype. IMPACT: What does this review add to the existing literature? To date, there is no literature exploring which particular syndromes exhibit mandibular prognathism as a common trait. Through this research, it was possibly to identify the particular syndromes that share the skeletal Class III phenotype (mandibular prognathism) as a common trait highlighting the common genetic and molecular pathways between different syndromes acknowledging their impact in craniofacial development.

East Asian and Southern European craniofacial class III phenotype: two sides of the same coin?

OBJECTIVES: The skeletal class III phenotype is a heterogeneous condition in populations of different ethnicities. This study aimed to analyse the joint and ethnicity-specific clustering of morphological features in skeletal class III patients of Asian and European origins. MATERIALS AND METHODS: This cross-sectional study involved South Korean and Spanish participants who fulfilled the cephalometric, clinical, and ethnic-related selection criteria. Radiographic records were standardised, calibrated, and measured. A total of 54 skeletal variables were selected for varimax factorial analysis (VFA). Subsequently, a cluster analysis (CA) was performed (mixed method: k-means and hierarchical clustering). Method error and precision were assessed using ICC, Student's t-test, and the Dahlberg formula. RESULTS: A total of 285 Korean and Spanish participants with skeletal class III malocclusions were analysed. After performing VFA and CA, the joint sample revealed three global clusters, and ethnicity-specific analysis revealed four Korean and five Spanish clusters. Cluster_1_global was predominantly Spanish (79.2%) and male (83.01%) and was characterised by a predominantly mesobrachycephalic pattern and a larger cranial base, maxilla, and mandible. Cluster_2_global and Cluster_3_global were mainly South Korean (73.9% and 75.6%, respectively) and depicted opposite phenotypes of mandibular projection and craniofacial pattern. CONCLUSIONS: A distinct distribution of Spanish and South Korean participants was observed in the global analysis. Interethnic and interethnic differences were observed, primarily in the cranial base and maxilla size, mandible projection, and craniofacial pattern. CLINICAL RELEVANCE: Accurate phenotyping, reflecting the complexity of skeletal class III phenotype across diverse populations, is critical for improving diagnostic predictability and future personalised treatment protocols.

Craniofacial characteristics in Van der Woude syndrome.

AIM: To describe the particular craniofacial characteristics of Van der Woude syndrome(VWS) patients compared to patients with a non-syndromic cleft (CG1) and to a malocclusive healthy population (CG2). MATERIAL AND METHODS: Retrospective case-control study. A sample of 110 matched-patients was recruited (VWS (n = 7), CG1 (n = 49), CG2 (n = 49)). Subsequently, 37 radiometric variables were analysed and the dental-skeletal ages were determined. The intra/inter-observer method errors were quantified. Descriptive statistics were computed, and different inferential analysis tests were used depending on the normality of the data (Chi-square test, Fisher's exact test, paired Student's T-test, Mann-Whitney U test) (p-value < 0.05). Pairwise comparisons were corrected by Bonferroni's criteria. RESULTS: VW-patients presented specific craniofacial characteristics and morphology. A marked tendency to the vertical growth pattern was found in VW-patients compared to CG1-CG2 (p < 0.001); at the sagittal level, skeletal class II caused by mandibular retrognathism, with a greatly increased ANB angle compared to CG1 (p = 0.042). Dental analysis showed that the lower incisor was more retruded and retroclined (p < 0.05 in all cases) and the interincisal angulation was increased (p < 0.001 (CG2)). At the profile level, an open nasolabial angle (p = 0.040; CG1) and a more protruding lower lip with respect to the Sn-Pg plane (p = 0.040 (CG1); p = 0.044 (CG2)) were observed. CONCLUSIONS: VW-patients present particular characteristics in the facial skeletal structures. There is a critical necessity to increase the evidence regarding specific clinical features and orofacial pathology of rare diseases such as VWS, which will help to these minorities to gain access in the future to a better quality of care with precise treatment and diagnostic necessities.

DIAGNOSTIC PERFORMANCE OF CONE-BEAM COMPUTED TOMOGRAPHY TO DIAGNOSE IN VIVO/IN VITRO ROOT RESORPTION: A SYSTEMATIC REVIEW AND META-ANALYSIS.

BACKGROUND: This review analyses the diagnostic performance of cone-beam computed tomography (CBCT) for the in vivo/in vitro detection of external root resorption (ERR) and critically analyses current and past methods of measuring or classifying ERR in vivo/in vitro in terms of radiation doses and cumulative radiation risks. METHODS: A diagnostic test accuracy (DTA) protocol was used for a systematic review of diagnostic methods following PRISMA guidelines. The protocol was registered with PROSPERO (ID: CRD42019120513). A thorough and exhaustive electronic search of 6 core electronic databases was performed, applying the ISSG Search Filter Resource. The eligibility criteria were designed [problem-intervention-comparison-outcomes (PICO) statement: Population, Index test, Comparator, Outcome] and methodological quality was assessed by QUADAS-2. RESULTS: Seventeen papers were selected from a total of 7841 articles. Six in vivo studies were assessed as having a low risk of bias. The overall sensitivity and specificity of CBCT for diagnosis of ERR was 78.12% and 79.25%, respectively. The highest and lowest sensitivity and specificity of CBCT for diagnosis of external root resorption are 42%-98% and 49.3%-96.3%. DISCUSSION: Most of the selected studies reported quantitative diagnoses with single linear measurements of ERR even though multislice radiographs were available. The cumulative radiation dose (µS) to radiation-sensitive structures, such as the bone marrow, brain and thyroid, was observed to increase using the 3-dimensional (3D) radiography methods reported. CONCLUSIONS: The highest and lowest sensitivity and specificity of CBCT for diagnosis of external root resorption are 42%-98% and 49.3%-96.3%. The minimum and maximum effective doses of dental CBCT for external root resorption diagnosis are 34 µSv and 1073 µSv.

Assessment of metal ion accumulation in oral mucosa cells of patients with fixed orthodontic treatment and cellular DNA damage: a systematic review.

Intraoral fixed appliances remain in the potentially corrosive environment of the mouth for an average of two years. Over time, corrosion causes the release of metal ions, such as nickel and chromium. These metals can become allergenic and cytotoxic, causing different conditions in the human body. The aim of this study therefore is to carry out a systematic review of the available scientific evidence on the accumulation of metal ions, and the genotoxic and cytotoxic effects in oral mucosa cells deriving from short- and long-term exposure to them. The systematic review is reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. The primary outcome (quantification of metal ion deposits and assessment of their genotoxic and/or cytotoxic effects) and secondary outcome (complementary analysis of cytotoxic and genotoxic effects) were examined. The Cochrane Collaboration tool and Toxicological data Reliability Assessment Tool (ToxRTool) were used for quality assessment. Once the search was performed, a total of seven articles met the inclusion criteria and were included in this study. Two main techniques were used to assess genotoxic effects: alkaline comet assay (6/7) and micronucleus method (1/7). Cytotoxicity was evaluated (4/7) using the trypan blue dye test. Accumulations of nickel (7/7), chromium (5/7), and other metals (zinc, cobalt, iron, manganese, molybdenum, titanium) were also quantified. The results allowed us to conclude that release of metal ions and acute cell and DNA damage in oral mucosa cells takes place in the early stages of treatment. However, more long-term studies are needed to evaluate chronic exposure to metals and DNA damage, as well as cellular capacity to recover DNA integrity.

Genetic factors contributing to skeletal class III malocclusion: a systematic review and meta-analysis.

OBJECTIVES: The present systematic review aims to report and critically assess the findings of the available scientific evidence from genetic association studies examining the genetic variants underlying skeletal class III malocclusion and its sub-phenotypes. MATERIAL AND METHODS: A pre-piloted protocol was registered and followed. The PubMed, Scopus, WOS, Cochrane Library, Gray Open literature, and CADTH databases were explored for genetic association studies following PICOS-based selection criteria. The research was reported in accordance with PRISMA statement and HuGE guidelines. The Q-genie tool was applied to assess the quality of genetic studies. Meta-analysis of genetic association studies was done by means of Meta-Genyo tool. RESULTS: A total of 8258 articles were retrieved, of which 22 were selected for in-depth analysis. Most of the studies did not differentiate between sub-phenotypes, and the cohorts were heterogeneous regarding ethnicity. Four to five principal components of class III malocclusion explained the phenotypic variation, and gene variants at MYO1H(rs10850110), BMP3(rs1390319), GHR (rs2973015,rs6184, rs2973015), FGF7(rs372127537), FGF10(rs593307), and SNAI3(rs4287555) (p < .05) explained most of the variation across the studies, associated to vertical, horizontal, or combined skeletal discrepancies. Meta-analysis results identified a statistically significant association between risk of class III malocclusion of A allele of the FBN3 rs7351083 [OR 2.13; 95% CI 1.1-4.1; p 0.02; recessive model]. CONCLUSION: Skeletal class III is a polygenic trait substantially modulated by ethnicity. A multicentric approach should be considered in future studies to increase sample sizes, applying multivariate analysis such as PCA and cluster analysis to characterize existing sub-phenotypes warranting a deeper analysis of genetic variants contributing to skeletal class III craniofacial disharmony. CLINICAL RELEVANCE: Grasping the underlying mechanisms of this pathology is critical for a fuller understanding of its etiology, allowing generation of preventive strategies, new individualized therapeutic approaches and more accurate treatment planification strategies.

Impact of photodynamic therapy versus ultrasonic scaler on gingival health during treatment with orthodontic fixed appliances.

OBJECTIVES: Poor oral hygiene during treatment with fixed appliances results in plaque accumulation. The presence of bacteria in the gingival crevice triggers an inflammatory reaction in the gingival tissues. The aim of this study was to compare the impact of two preventive treatments, photodynamic therapy (PDT), and ultrasonic scaler (US), on gingival health in patients under fixed orthodontic treatment. METHODS: Twenty orthodontic patients were randomly allocated to two groups: PDT or US. Each group received seven sessions [days 0, 15, 30, 45, 90 (3-months follow-up), 180 (6-months follow-up), 270 (9-months follow-up)] of experimental interventions, and clinical parameters [Plaque index(PI); gingival index(GI); probing depth(PD)], periodontopathogens [Agreggatibacter actinomycetemcomitans; Porphyromonas gingivalis; Prevotella intermedia; Micromonas micros; Fusobacterium nucleatum; Tannerella forsythia; Campylobacter rectus; Eikenella corrodens; Capnocytopaga sp.] and protein markers [IL-1ß;IL-1ra;IL-6;IL-10;TNF-α;FGF-2/FGF basic] were monitored at baseline and at 3, 6, and 9 months. ANOVA, Student's t-test with Bonferroni correction and ANOVA with multiple rank test were used to identify differences between groups (P < 0.05). RESULTS: Clinical assessments [PI, GI, and PD] yielded no differences (P > 0.05) between groups, which showed a major decrease at the start of the trial. Reductions in total colony forming units (log CFU reduction) were observed with both treatments, although to a greater extent in the PDT group, but with no differences between groups (P > 0.05). Similar reductions in log CFU counts of P. gingivalis, P. intermedia, and F. nucleatum were observed in both groups (P > 0.05). The two groups also showed similar trends for inflammatory mediators with decreased levels of IL-1ß, IL-10, and TNF-α, whereas IL-6 and IL-1ra levels remained stable and those of FGF-2 were increased after both interventions, with no differences (P > 0.05) between groups. CONCLUSION: Both PDT and US methods proved similar effectiveness for the treatment of gingival inflammation induced by fixed orthodontic appliances. Lasers Surg. Med. 51:256-267, 2019. © 2018 Wiley Periodicals, Inc.

Subclustering in Skeletal Class III Phenotypes of Different Ethnic Origins: A Systematic Review.

OBJECTIVE: We aimed to systematically review articles investigating the efficiency of the clustering of skeletal class III malocclusion phenotypic subtypes of different ethnic origins as a diagnostic tool. METHODS: The review protocol was structured in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement and registered in Prospero (CRD42016053865). A survey of articles published up to March 2018 investigating the identification of different subgroups of skeletal class III malocclusion via cluster analysis was performed using 11 electronic databases. Any type of study design that addressed the classification of subclusters of class III malocclusion was considered. The Newcastle-Ottawa scale for cohort and cross-sectional (modified) studies was used for quality assessment. RESULTS: The final selection included 7 studies that met all the criteria for eligibility (% overall agreement 0.889, free marginal kappa 0.778). All studies identified at least 3 different types of class III clusters (ranging from 3 to 14 clusters; the total variation of the prevalence of each cluster ranged from 0.2% to 36.0%). The main shared variables used to describe the more prevalent clusters in the studies included were vertical measurements (Ar-Go-Me: 117.51°-135.8°); sagittal measurements: maxilla (SNA: 75.3°-82.95°), mandible (SNB: 77.03°-85.0°). With regard to ethnicity, a mean number of 8.5 and 3.5 clusters of class III were retrieved for Asian and Caucasian population, respectively. CONCLUSIONS: The total number of clusters identified varied from 3 to 14 to explain all the variability in the phenotype class III malocclusions. Although each extreme may be too simple or complex to facilitate an exhaustive but useful classification for clinical use, a classification system including 4 to 7 clusters may prove to be efficient for clinical use in conjunction with complete and meticulous subgrouping. CLINICAL SIGNIFICANCE: The identification and description of a subclustering classification system may constitute an additional step toward more precise orthodontic/orthopedic diagnosis and treatment of skeletal class III malocclusion.

How effective is the Invisalign® system in expansion movement with Ex30' aligners?

OBJECTIVES: The aims of this study are to validate a new method for quantifying the predictability of expansion movement with the Invisalign® system and to determine whether there are statistically significant differences between planned expansion with ClinCheck® and actual clinical quantification using upper post-treatment model comparisons. MATERIALS AND METHODS: A sample of 116 patients subjected to expansion with Invisalign® was studied. The following variables were measured at T1 and T2 on 3D models and ClinCheck®: canine gingival width, first premolar gingival width, second premolar gingival width, first molar gingival width, canine cuspid width, first premolar cuspid width, second premolar cuspid width, first molar cuspid width, canine depth, arch depth, first molar rotation, first right and left molar rotation, and first molar inclination. RESULTS: Measurement error was tested, showing good precision for all variables. The paired test showed non-significant differences between the 3D model and ClinCheck® at T1 for all variables except first molar cuspid width and arch depth. Statistically significant differences were found for canine gingival width, first premolar gingival width, second premolar gingival width, first molar gingival width, canine cuspid width, first premolar cuspid width, second premolar cuspid width, first molar cuspid width, and canine depth when the 3D model and ClinCheck® were compared at T2. CONCLUSIONS: Differences between the 3D model and ClinCheck® at T2 showed that planned expansion at the end of treatment is not predictable. CLINICAL RELEVANCE: This is the first in vivo human study to quantify the predictability of expansion in patients with Invisalign® Ex30 material.

Clinical and radiographic evaluation of white MTA versus formocresol pulpotomy: A 48-month follow-up study.

PURPOSE: To determine whether there were differences between formocresol (FC) and white mineral trioxide aggregate (MTA) pulpotomy in terms of clinical and radiographic signs or effects upon the permanent successor over a long term. METHODS: A total of 212 molars (74 treated with FC and 138 with white MTA) corresponding to 129 subjects [66 females (51.1%) and 63 males (48.8%)] were evaluated. The coronal pulp was carefully amputated up to the entrance of the root canals using a sharp spoon excavator. Post-amputation bleeding was confirmed to be bright red and was seen to subside after applying 2-3 minutes of gentle pressure with a sterile cotton pellet. One group was treated with a 1:5 dilution of formocresol (20% Buckley's formocresol solution), while a second group was treated using white MTA powder (ProRoot). RESULTS: There were no significant differences in clinical success rate between the two groups (89.9% in the white MTA group versus 82.5% if the FC group). However, the radiographic success rate was significantly greater for white MTA versus FC. The radiographic failure rate in the molars treated with MTA was 7.9% versus 18.9% with FC. Regarding alterations in the timing of eruption, early and delayed eruption were respectively recorded in 7.24% and 8.69% of the cases in the MTA group, versus 9.45% and 4.05% of the cases in the FC group. Thus, neither group showed relevant alterations in the timing of eruption. CLINICAL SIGNIFICANCE: Mineral trioxide aggregate showed a significantly greater radiographic success rate than formocresol in pulpotomy in primary teeth over 6 to 48 months of follow-up. MTA may be indicated as a substitute of formocresol in pulpotomy treatments of temporary molars, with no pathological consequences of any kind to the permanent successor premolar.

Five radiographic methods for assessing skeletal maturity in a Spanish population: is there a correlation?

OBJECTIVES: The need for accurate techniques of estimating age has sharply increased in line with the rise in illegal migration and the political, economic and socio-demographic problems that this poses in developed countries today. The methods routinely employed for determining chronological age are mainly based on determining skeletal maturation using radiological techniques. The objective of this study was to correlate five different methods for assessing skeletal maturation. MATERIALS AND METHODS: 606 radiographs of growing patients were analyzed, and each patient was classified according to two cervical vertebral-based methods, two hand-wrist-based methods and one tooth-based method. Spearman's rank-order correlation coefficient was applied to assess the relationship between chronological age and the five methods of assessing maturation, as well as correlations between the five methods (p < 0.05). RESULTS: Spearman's rank correlation coefficients for chronological age and cervical vertebral maturation stage using both methods were 0.656/0.693 (p < 0.001), respectively, for males. For females, the correlation was stronger for both methods. The correlation coefficients for chronological age against the two hand-wrist assessment methods were statistically significant only for Fishman's method, 0.722 (p < 0.001) and 0.839 (p < 0.001), respectively for males and females. CONCLUSIONS: The cervical vertebral, hand-wrist and dental maturation methods of assessment were all found to correlate strongly with each other, irrespective of gender, except for Grave and Brown's method. The results found the strongest correlation between the second molars and females, and the second premolar and males. CLINICAL RELEVANCE: This study sheds light on and correlates with the five radiographic methods most commonly used for assessing skeletal maturation in a Spanish population in southern Europe.

Fibromyalgia syndrome and temporomandibular disorders with muscular pain. A review.

OBJECTIVES: Temporomandibular disorders (TMD) refer to a group of clinical picture affecting the masticatory muscles and temporomandibular joint that are characterized by muscular or joint pain, dysfunction (limited or altered functions) and joint noises, as well as other associated symptoms, such as tension headaches, otalgia, dizziness, tinnitus, and others. Fibromyalgia (FM) is a syndrome of unknown etiology involving generalized chronic pain accompanied, in a high percentage of cases, by other symptoms such as asthenia, anxiety, depression, sleep disturbances, and other less frequent symptoms, such as temporomandibular disorders (TMD). DATA: Data were compiled by two experienced examiners following a specific form. SOURCES: An electronic search was carried out in the Cochrane Central Register of Controlled Trials (CENTRAL), PUBMED, and SCOPUS electronic databases (up to April 2016, unrestricted by date or language). STUDY SELECTION: Comparative clinical studies with patients with both clinical pictures involving the study of pathogenic processes. CONCLUSIONS: Fibromyalgia and temporomandibular disorders with muscle pain both have profiles that affect the muscular system and therefore share many epidemiological, clinical, and physiopathological symptoms. Because of this, we are led to think that there is, if not a common etiology, at least a common pathogenesis. This article revises the physiopathological processes of both clinical pictures in an attempt to determine their similarities and likenesses. This would undoubtedly help in providing a better therapeutic approach.

Childhood Obesity and Delayed Gratification Behavior: A Systematic Review of Experimental Studies.

OBJECTIVE: To evaluate the extent of the association between instant gratification behavior and childhood obesity. STUDY DESIGN: PubMed, Scopus, EMBASE, EBSCOhost, and Cochrane databases were searched for the terms delayed gratification, children, and obesity. Studies were eligible if they included a sample of at least 100 children who were made to choose between an immediate reward and a larger one later, with the authors comparing the response in different populations and observing some relationship with obesity. A specifically designed data extraction form was used, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The methodologic quality of the included studies was assessed with the methodologic index for nonrandomized studies. RESULTS: Nine articles were included after we applied the inclusion and exclusion criteria. Almost all studies conducted the test in populations of preschool children and offered food and/or nonfood rewards. The studies found a clear relationship between an inability to defer gratification and overweight and obesity. The quality assessment of the publications was ranked high in 5 studies and medium in 4. CONCLUSIONS: Children with the inability to delay gratification are more likely to be overweight or obese. Observation of such trends is useful in its implications for reeducation programs. Although the methodologic quality of the eligible studies was acceptable, additional experimental controlled studies are required to associate these behaviors with other aspects.

Bone Density and Dental External Apical Root Resorption.

When orthodontic patients desire shorter treatment times with aesthetic results and long-term stability, it is important for the orthodontist to understand the potential limitations and problems that may arise during standard and/or technology-assisted accelerated treatment. Bone density plays an important role in facilitating orthodontic tooth movement (OTM), such that reductions in bone density can significantly increase movement velocity. Lifestyle, genetic background, environmental factors, and disease status all can influence a patients' overall health and bone density. In some individuals, these factors may create specific conditions that influence systemic-wide bone metabolism. Both genetic variation and the onset of a bone-related disease can influence systemic bone density and local bone density, such as observed in the mandible and maxilla. These types of localized density changes can affect the rate of OTM and may also influence the risk of unwanted outcomes, i.e., the occurrence of dental external apical root resorption (EARR).

Prevalence of alterations in the characteristics of smile symmetry in an adult population from southern Europe.

STATEMENT OF PROBLEM: Deviation from the facial midline and inclination of the dental midline or occlusal plane has been described as extremely influential in the layperson's perceptions of the overall esthetics of the smile. PURPOSE: The purpose of this study was to determine the prevalence of deviation from the facial midline and inclination of the dental midline or occlusal plane in a selected sample. MATERIAL AND METHODS: White participants from a European population (N=158; 93 women, 65 men) who met specific inclusion criteria were selected for the present study. Standardized 1:1 scale frontal photographs were made, and 3 variables of all participants were measured: midline deviation, midline inclination, and inclination of the occlusal plane. Software was used to measure midline deviation and inclination, taking the bipupillary line and the facial midline as references. Tests for normality of the sample were explored and descriptive statistics (means ±SD) were calculated. The chi-square test was used to evaluate differences in midline deviation, midline inclination, and occlusion plane (α=.05) RESULTS: Frequencies of midline deviation (>2 mm), midline inclination (>3.5 degrees), and occlusal plane inclination (>2 degrees) were 31.64% (mean 2.7±1.23 mm), 10.75% (mean 7.9 degrees ±3.57), and 25.9% (mean 9.07 degrees ±3.16), respectively. No statistically significant differences (P>.05) were found between sex and any of the esthetic smile values. CONCLUSIONS: The incidence of alterations with at least 1 altered parameter that affected smile esthetics was 51.9% in a population from southern Europe.

Effectiveness of biologic methods of inhibiting orthodontic tooth movement in animal studies.

INTRODUCTION: A number of biologic methods leading to decreased rates of orthodontic tooth movement (OTM) can be found in the recent literature. The aim of this systematic review was to provide an overview of biologic methods and their effects on OTM inhibition. METHODS: An electronic search was performed up to January 2016. Two researchers independently selected the studies (kappa index, 0.8) using the selection criteria established in the PRISMA statement. The methodologic quality of the articles was assessed objectively according to the Methodological Index for Non-Randomized Studies scale. RESULTS: We retrieved 861 articles in the initial electronic search, and 57 were finally analyzed. Three biologic techniques were identified as reducing the rate of OTM: chemical methods, low-level laser therapy, and gene therapy. When the experimental objective was to slow down OTM, pharmacologic modulation was the most frequently described method (53 articles). Rats were the most frequent model (38 of 57 articles), followed by mice (9 of 57), rabbits (4 of 57), guinea pigs (2 of 57), dogs (2 of 57), cats (1 of 57), and monkeys (1 of 57). The sample sizes seldom exceeded 25 subjects per group (6 of 57 articles). The application protocols, quality, and effectiveness of the different biologic methods in reducing OTM varied widely. CONCLUSIONS: OTM inhibition was experimentally tested with various biologic methods that were notably effective at bench scale, although their clinical applicability to humans was rarely tested further. Rigorous randomized clinical trials are therefore needed to allow the orthodontist to improve the effect of translating them from bench to clinic.

Dental fear in children: the role of previous negative dental experiences.

OBJECTIVES: The aims of this study were to determine the potential main sources of anxiety in children visiting the dental office and to examine whether negative experiences influence the development of dental fear. METHODS: Six hundred six subjects from the same pediatric dental office were consecutively invited to participate in the study (303 children/303 parents). An adapted version of the Wong-Baker FACES Pain Rating Scale and Corah's Dental Anxiety Scale were used to rate anxiety in children and parents. Clinical variables were collected by the same experienced pediatric dentist, with a view to determining their potential influence upon the development of fears. Descriptive statistics (mean, standard deviation), along with the Mann-Whitney U test, were used to determine the association between clinical variables and anxiety levels. Correlations were established using the Spearman coefficient (r) (p < 0.05). RESULTS: No statistical differences were observed in anxiety levels with respect to patient gender (p > 0.05). Greater anxiety levels were observed in 4- and 5-year-old children (n = 56/55, respectively), with a negative correlation between age and anxiety level (r = -0.176; p = 0.002) and between parent anxiety level and patient age (r = -0.154; p = 0.007). A strong positive correlation was found between the anxiety levels of the parents and children (r = 0.954; p < 0.001). In addition, a moderate positive correlation was found between elevated anxiety levels in children (r = 0.381; p < 0.001) and parents (r = 0.454; p < .001) and the number of previous treatments in other dental offices. CONCLUSIONS: Dental fear in children is strongly associated with inadequate dental management, causing anxiety levels to increase in both the children and parents.

Short-term effect of removal of fixed orthodontic appliances on gingival health and subgingival microbiota: a prospective cohort study.

OBJECTIVE: The aim of this prospective longitudinal study was to assess and compare the microbiological and clinical parameters of patients wearing a fixed orthodontic appliance, as opposed to 10 days after the bracket had been removed following treatment. MATERIALS AND METHODS: In total, 122 patients participated in this study; 61 of the subjects were assessed at baseline (wearing a fixed orthodontic appliance: T1) and 10 days after bracket removal (T2). The other 61 individuals had never worn an orthodontic appliance before and these subjects served as controls (CT). Subgingival plaque samples were assessed for bleeding on probing (GBI) and plaque index (VPI). PCR of 16s rDNA, followed by reverse species-specific hybridization for Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Tannerella forsythia and Treponema denticola were performed. A descriptive analysis was conducted; chi-squared, Student's matched and unmatched t-tests, the point biserial correlation coefficient and the McNemar test were used to test for differences between groups (p < 0.05). RESULTS: The GBI and VPI clinical parameters showed statistical differences (p < 0.05) between T1-T2, T1-CT and T2-CT. The prevalence of T. denticola had significantly decreased (p = 0.039) 10 days after appliance removal. At T2, a significant positive correlation was found between GBI and A. actinomycetemcomitans (p < 0.01) and between clinical parameters and P. intermedia. In patients without a fixed orthodontic appliance (T2 and CT), there was a significant positive correlation between T. forsythia and VPI. CONCLUSION: Local factors associated with the wearing of a fixed orthodontic appliance influence changes in subgingival plaque that leads to more inflammation and bleeding.

Prevalence and complications of trauma to the primary dentition in a subpopulation of Spanish children in southern Europe.

BACKGROUND: During the first years of life, when children begin to walk and socialize, they are particularly vulnerable to traumatic injuries to the primary teeth; indeed, after dental caries, such injuries are the second most frequent cause of pediatric dental consultation. Nonetheless, the reported prevalence of trauma to the primary teeth varies depending on the literature source, type of injury, the patient's age, and the most common associated complications. AIM: To analyze new epidemiological data and complications associated with traumatic injuries to the primary teeth of Spanish children. MATERIAL AND METHODS: A retrospective study was carried out in a subpopulation of 879 Spanish children in southern Europe aged between one and 7 years old, with primary and early mixed dentition. Clinical and radiological records were obtained from all pediatric patients who presented trauma to the primary teeth, with a follow-up period of 3-5 years. RESULTS: A total of 21.72% of children examined had some kind of dental trauma and the most common age range for injuries to the primary teeth was 1-3 years old. The most common injuries in deciduous teeth were subluxation (47.29% of injuries affected the periodontal ligament), intrusion (23.15%), and avulsion (13.63%). On the other hand, comparatively more complications were recorded as a result of intrusion (32 of 47 intruded teeth). CONCLUSIONS: In this Spanish subpopulation, a pediatric dental consultation as a result of traumatic dental injuries in primary dentition is most frequent in 1- and 2-year-olds, and subluxation is the commonest injury in the primary dentition. In turn, intrusion is associated with an increased frequency of complications in both the deciduous and the permanent teeth.