Clinical Behavior of Short Dental Implants: Systematic Review and Meta-Analysis

Short implants are an increasingly common alternative to other surgical techniques in areas where bone availability is reduced. Despite the advantages they offer, a variety of biological repercussions have been described in the literature that can even lead to the loss of these. The aim of this systematic review and meta-analysis was to analyze the impact of the use of short implants on their survival and on peri-implant bone loss, evaluating the influence that length, diameter, and crown-to-implant ratio (C/I) have on these parameters. This systematic review was based on guidelines proposed by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). An electronic se…

Using NMR in saliva to identify possible biomarkers of glioblastoma and chronic periodontitis

Nowadays there is increasing interest in identifying-and using-metabolites that can be employed as biomarkers for diagnosing, treating and monitoring diseases. Saliva and NMR have been widely used for this purpose as they are fast and inexpensive methods. This case-control study aimed to find biomarkers that could be related to glioblastoma (GBL) and periodontal disease (PD) and studied a possible association between GBL and periodontal status. The participants numbered 130, of whom 10 were diagnosed with GBL and were assigned to the cases group, while the remaining 120 did not present any pathology and were assigned to the control group. On one hand, significantly increased (p < 0.05) meta…

Clinical Behavior of Ceramic, Hybrid and Composite Onlays. A Systematic Review and Meta-Analysis

A systematic review and meta-analysis was performed to analyze the survival of onlay restorations in the posterior region, their clinical behavior according to the material used (ceramic reinforced with lithium disilicate, conventional feldspathic ceramic or reinforced with leucite; hybrid materials and composite), possible complications, and the factors influencing restoration success. The systematic review was based on the preferred reporting items for systematic reviews and meta-analyses (PRISMA) statement, without publication date or language restrictions. An electronic search was made in the PubMed, Scopus, Embase, and Cochrane databases. After discarding duplicate publications and stu…

Oral health knowledge in relation to educational level in an adult population in Spain.

Background To analyze the relationship between oral health knowledge and educational level among an adult population in Spain, and between oral health knowledge and subjects' oral hygiene practices, dietary habits, toxic habits, and oral quality of life. Material and methods This transversal study used the Comprehensive Measure of Oral Health Knowledge (CMOHK) questionnaire to evaluate subjects' knowledge and understanding of oral health, and the World Health Organization oral health questionnaire for adults to evaluate dietary, oral hygiene, toxic habits, and oral quality of life. Participants (n=400) gave their informed consent and data release permission before taking part in the study, …

Caries prevalence in children from Valencia (Spain) using ICDAS II criteria, 2010

Objectives: To assess the oral health status of the child population and its evolution over the 2004-2010 period. Study Design: A descriptive cross-sectional study of the entire schoolchild population of the Valencia region of Spain was conducted using cluster sampling. Seventy schools were selected. The sample size was 1373 pupils, aged 6, 12 and 15 years. The children were examined in November and December 2010, at their schools, by 6 examiners calibrated in the ICDAS II method. The descriptive statistics, comparison of means and comparison of proportions (p0) was 30% in primary dentition at 6 years and 37.7% and 43.6% in permanent dentition at 12 and 15 years respectively. At 6, 12 and 1…

Correction: Mechanical properties of provisional dental materials: A systematic review and meta-analysis.

Provisional restorations represent an important phase during the rehabilitation process, knowledge of the mechanical properties of the available materials allows us to predict their clinical performance. At present, there is no systematic review, which supports the clinicians’ criteria, in the selection of a specific material over another for a particular clinical situation. The purpose of this systematic review and meta-analysis was to assess and compare the mechanical properties of dimethacrylates and monomethacrylates used in fabricating direct provisional restorations, in terms of flexural strength, fracture toughness and hardness. This review followed the PRISMA guidelines. The searche…

A comparative study of aesthetic perceptions of malocclusion among general practice dentists, orthodontists and the public using a visual analogue scale (VAS) and the IOTN-AC.

Background Perception of malocclusion varies among individuals and among patients and practitioners. Although several indices that tend to coincide in many aspects and unify criteria, no single index has been recognised as the most suitable for assessing orthodontic treatment need. Moreover, orthodontists are not always aware of the differences in perception of malocclusion between patients and practitioners. Objetives To examine the perception of dental anaesthetics amongst dentists, orthodontists and the general population, study the relationship between the perception of dental aesthetics and the severity of the malocclusion, using the visual analogue scale and the IOTN-AC, and investiga…

Caries Prevalence Evolution and Risk Factors among Schoolchildren and Adolescents from Valencia (Spain): Trends 1998–2018

The aim of this study was to determine the caries status and risk factors in the schoolchildren of Spain&rsquo

Effects of mandibular setback surgery on upper airway dimensions and their influence on obstructive sleep apnoea - a systematic review.

Abstract Background Mandibular setback used to be the traditional treatment of choice for correcting mandibular prognathism. Nowadays, bimaxillary surgery is preferred. Several authors have asserted that mandibular setback causes a relative narrowing of the upper airway (UA) that could trigger obstructive sleep apnoea (OSA); however, its potential role in OSA development is still much debated. Another controversial subject is whether changes in airway space caused by the procedure are permanent. Objectives To ascertain the consequences for UA size and shape of mandibular setback surgery in comparison with bimaxillary surgery (maxillary advancement with Le Fort I and mandibular setback), and…

Diagnostic agreement in the assessment of orthodontic treatment need using the Dental Aesthetic Index and the Index of Orthodontic Treatment Need

The aim of this study was to estimate the diagnostic agreement between assessments of orthodontic treatment need of a child population using the Dental Aesthetic Index (DAI) and the Index of Orthodontic Treatment Need (IOTN). A cross-sectional study of a representative random sample of children aged 12 ( n = 475) and 15–16 ( n = 398) years was carried out in the Valencia region of Spain. A Student's t -test was used to compare the DAI means by gender and age and a chi-square test to compare the proportions of the population in need of orthodontic treatment. To calculate the agreement between the two indices, intra-class correlation coefficient and Kappa statistics were employed. Of the 12-y…

Comparison of the remineralizing effect of a sodium fluoride mouthrinse versus a sodium monofluorophosphate and calcium mouthrinse: an in vitro study.

Objectives The aim of this in vitro study was to compare the remineralizing effect of three rinses: (A) 0.17% sodium monofluorphosphate and 0.05% calcium glycerophosphate (220 ppm fluoride), (B) 0.05% sodium fluoride (220 ppm fluoride) and (C) control mouthrinse (without fluoride or calcium). Method and Materials Demineralized areas were created in 90 pieces of bovine enamel by submerging them in an acid solution (pH 4.4) for 48 hours. Part of the surface was painted with nail varnish to preserve the demineralized area and the specimens were assigned at random to three groups. The specimens were stored in artificial saliva at pH 7 and 37ºC for 30 days. Twice daily they were immersed for 60 …

Factors associated with edentulousness in an elderly population in Valencia (Spain) Factores asociados con el edentulismo en población anciana de Valencia (España)

Objective: To determine the prevalence of edentulism and its association with various socioeconomic factors and oral health habits in the population aged 65-74 years old in the region of Valencia. Methods: A cross sectional study was designed. Thirty-four primary health centers and five nursing homes were chosen at random in the region of Valencia (10-15 voluntary participants per sampling point). Clinical examinations were carried out by three calibrated dentists (kappa>0.85) in the same centers. The total sample consisted of 531 individuals (235 men and 296 women). Results: The percentage of toothlessness was 20.7% and the mean number of natural teeth present was 14.92. The prevalence of …

Effects of mandibular advancement surgery on the temporomandibular joint and muscular and articular adaptive changes--a systematic review.

The objective of this study was to assess the anatomical changes to the condyle and articular disc following mandibular advancement surgery, the adaptation of the masticatory muscles, and the improvement or worsening of temporomandibular disorders (TMD) in patients with pre-existing disorders and those who developed them following surgery. Four databases were searched systematically: PubMed, Scopus, Embase, and Cochrane Library. Of the 544 articles initially selected, 219 were duplicates and a further 165 were excluded on the basis of their titles and abstracts. On reading the full text, 89 were excluded because they were of no interest and 43 because they did not meet the inclusion criteri…

Need for Orthodontic Treatment in Pupils Aged between 12 and 15 in the Valencian Region (Spain)

The World Health Organization recommends carrying out periodic epidemiological studies in order to provide a basis for the evaluation of the state of health of the population at any given time

Predictive validity of the GOSLON Yardstick index in patients with unilateral cleft lip and palate: A systematic review

Among the various indices developed for measuring the results of treatment in patients born with unilateral cleft lip and palate (UCLP), the GOSLON Yardstick index is the most widely used to assess the efficacy of treatment and treatment outcomes, which in UCLP cases are closely linked to jaw growth. The aim of this study was to conduct a systematic review to validate the predictability of growth using the GOSLON Yardstick in patients born with UCLP. A systematic literature review was conducted in four Internet databases: Medline, Cochrane Library, Scopus and Embase, complemented by a manual search and a further search in the databases of the leading journals that focus on this topic. An el…

Validation of the Maslach Burnout Inventory-Human Services Survey for Estimating Burnout in Dental Students.

The aim of this study was to examine the validity and reliability of the Maslach Burnout Inventory-Human Services Survey (MBI-HSS) as a tool for assessing the prevalence and level of burnout in dental students in Spanish universities. The survey was adapted from English to Spanish. A sample of 533 dental students from 15 Spanish universities and a control group of 188 medical students self-administered the survey online, using the Google Drive service. The test-retest reliability or reproducibility showed an Intraclass Correlation Coefficient of 0.95. The internal consistency of the survey was 0.922. Testing the construct validity showed two components with an eigenvalue greater than 1.5, w…

Factores asociados con el edentulismo en población anciana de Valencia (España)

Objective: To determine the prevalence of edentulism and its association with various socioeconomic factors and oral health habits in the population aged 65-74 years old in the region of Valencia. Methods: A cross sectional study was designed. Thirty-four primary health centers and five nursing homes were chosen at random in the region of Valencia (10-15 voluntary participants per sampling point). Clinical examinations were carried out by three calibrated dentists (kappa>0.85) in the same centers. The total sample consisted of 531 individuals (235 men and 296 women). Results: The percentage of toothlessness was 20.7% and the mean number of natural teeth present was 14.92. The prevalence of …

Orthodontic treatment need in a Spanish young adult population

Objectives: Orthodontic treatment need has often been assessed in child populations, but few studies employing internationally-recognized indices have been conducted in adult or young adult populations. The aim of this study was to determine the orthodontic treatment need of a young adult population in Spain by means of the Dental Aesthetic Index (DAI), the Index of Orthodontic Treatment Need (IOTN) and the need perceived by the patients. Study design: A cross-sectional epidemiological study was conducted in a broad, representative sample of 671 adults aged between 35 and 44 years using health centers in the Valencia Region of Spain, following the recommendations of the World Health Organiz…

Corticotomies as a surgical procedure to accelerate tooth movement during orthodontic treatment : a systematic review

Background One of the main aims of orthodontists is to reduce the treatment time as much as possible, particularly in view of the rise in demand for orthodontic treatment among adult patients. The objective of this systematic review was to examine the effectiveness of corticotomy as a surgical procedure that accelerates orthodontic tooth movement, together with its possible adverse effects. Material and Methods A systematic review of articles in 4 databases, Pubmed, Cochrane, Scopus and Embase, complemented by a manual search, identified 772 articles. The duplicates were eliminated and a critical reading of titles and abstracts led to the rejection of articles that did not meet the objectiv…

Linear and Volumetric Mandibular Asymmetries in Adult Patients With Different Skeletal Classes and Vertical Patterns: A Cone-Beam Computed Tomography Study

AbstractThis study aimed to quantify the height of the mandibular condyle and ramus, condylar volume, and the asymmetry index in adult patients of different sex, skeletal class and vertical pattern using Cone-Beam Computed Tomography (CBCT), and to determine whether there were differences between these groups. The study used CBCT scans of 159 patients with a mean age of 32.32 ± 8.31 years. InVivoDental® software was used to perform both linear (condylar, ramal, and total height) and condylar volume measurements. Linear and volumetric asymmetries were calculated. There were not significant differences between right and left sides. The mean value obtained for condyle height was 7.27 mm, ramus…

Effect of Computer-Aided Navigation Techniques on the Accuracy of Endodontic Access Cavities: A Systematic Review and Meta-Analysis

Simple Summary The endodontic access cavity is an essential step in the root canal treatment allowing the access and location of the root canal system. The inaccuracy during the endodontic access cavitie can lead to intraoperative complications such as missed root canals or root perforations, and hence affect the prognosis of the root canal treatment. The development of computer-aided static and dynamic navigation techniques has improved the accuracy of endodontic access cavities and root canal location; however, it is necessary a comparative analysis to clarify which of the computer-aided navigation system is more accurate. This systematic review and meta-analysis aims to clarify the root …

Hypomineralized Second Primary Molars as Predictor of Molar Incisor Hypomineralization

AbstractMolar incisor hypomineralization (MIH) is a developmental defect of dental enamel that shares features with hypomineralized second primary molars (HSPM). Prior to permanent tooth eruption, second primary molars could have predictive value for permanent molar and incisor hypomineralization. To assess this possible relationship, a cross-sectional study was conducted in a sample of 414 children aged 8 and 9 years from the INMA cohort in Valencia (Spain). A calibrated examiner (linear-weighted Kappa 0.83) performed the intraoral examinations at the University of Valencia between November 2013 and 2014, applying the diagnostic criteria for MIH and HSPM adopted by the European Academy of …

Case-control study of craniomandibular disorders in patients with fibromyalgia

Background: Fibromyalgia is a clinical syndrome characterized by chronic widespread pain, which is non-articular and is predominantly experienced in the muscles and vertebral column, and by extensive heightened sensitivity to local pressure at many specific points The purpose of this study was to measure differences in the level of painful symptoms and in the movements of the mandible in a group of patients who had been diagnosed as suffering from fibromyalgia, in comparison with a control group. The anxiety and subjective pain levels and their relation with mandibular mobility were also compared. Materials and Methods: A case-control study was designed. The temporomandibular joints and mas…

Prevalence of fimA genotypes of Porphyromonas gingivalis and other periodontal bacteria in a Spanish population with chronic periodontitis

Objectives: The aim of this study was to determine the prevalence of the different fimA genotypes of Porphyromonas gingivalis in adult Spanish patients with chronic periodontitis, patients with gingivitis and periodontally healthy subjects, and the relationship between these genotypes and other periodontopathogenic bacteria. Study design: Samples of subgingival plaque were taken from 86 patients (33 with chronic periodontitis, 16 with gingivitis, and 37 periodontally healthy) in the course of a full periodontal examination. PCR was employed to determine the presence of the 6 fimA genotypes of Porphyromonas gingivalis (I-V and Ib) and of Aggregatibacter actinomycetemcomitans, Tannerella fors…

Mechanical properties of provisional dental materials: A systematic review and meta-analysis

Provisional restorations represent an important phase during the rehabilitation process, knowledge of the mechanical properties of the available materials allows us to predict their clinical performance. At present, there is no systematic review, which supports the clinicians' criteria, in the selection of a specific material over another for a particular clinical situation. The purpose of this systematic review and meta-analysis was to assess and compare the mechanical properties of dimethacrylates and monomethacrylates used in fabricating direct provisional restorations, in terms of flexural strength, fracture toughness and hardness. This review followed the PRISMA guidelines. The searche…

Diagnostic validity of ICDAS II, VistaProof and a combination of these two methods. An in vitro study in pre-cavitated lesions

Purpose In view of the present fall in advanced cavitation lesion prevalence, diagnostic methods have been developed to assist in assessing and measuring pre-cavitation lesions. The purpose of this study was to assess the VistaProof fluorescence-based system in vitro and compare the results with those of visual examination using the ICDAS II criteria. Methods 100 permanent teeth were collected and 65 were chosen at random for this study. Two separate examiners each examined them twice, 3 weeks apart, assessing them in accordance with ICDAS II. They were subsequently examined with the VistaProof system and the images were stored in the computer program. After obtaining all these data, the te…

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 usi…

Epidemiologic study of molar-incisor hypomineralization in 8-year-old Spanish children

Aim To find the prevalence of molar-incisor hypomineralization (MIH) in a random sample of Spanish children, and to investigate the gender influence, distribution of defects, the treatment need associated and the relation between this disorder and dental caries. Design A cross-sectional study was carried out to determine MIH and caries prevalence in a randomly selected sample of 840 children from the 8-year-old population of the Valencia region of Spain. The examinations were carried out in the children's schools by one examiner who had previously been calibrated with the MIH diagnostic criteria of the European Academy of Paediatric Dentistry (EAPD). Results The percentage of children with …

Clinical and radiographic diagnosis of approximal and occlusal dental caries in a low risk population

Objective: Determine the agreement between visual detection, conventional radiology and digital radiology methods in the diagnosis of interproximal and occlusal caries in the posterior teeth of a group of patients with low caries prevalence. Materials and Methods: Visual, conventional radiographic and digital radiographic (Digora®, Soredex, Sweden) caries diagnosis was performed in a group of patients (n=30) of both sexes with ages ranging from 15 to 65 years (x = 34 years). Agreement was estimated by the linear weighted kappa index. Results: Kappa = 0.17 was obtained between the visual examination and the conventional radiographic examination and Kappa = 0.16 between the visual examination…

Stimulated and unstimulated saliva samples have significantly different bacterial profiles

Epidemiological studies use saliva on a regular basis as a non-invasive and easy-to-take sample, which is assumed to be a microbial representative of the oral cavity ecosystem. However, comparative studies between different kinds of saliva samples normally used in microbial studies are scarce. The aim of the current study was to compare oral microbiota composition between two different saliva samples collected simultaneously: non-stimulated saliva with paper points and stimulated saliva collected after chewing paraffin gum. DNA was extracted from saliva samples of ten individuals, then analyzed by 16S rRNA pyrosequencing to describe bacterial diversity. The results demonstrate significant d…

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 a…

Relationship between caries, body mass index and social class in Spanish children

Abstract Objective: To determine the association between caries, body mass index (BMI) and social class in child population of the Valencia region (Spain) at 6, 12 and 15 years, and study. Methods: In a cross sectional study of 1326 children aged 6 (n = 488), 12 (n = 409) and 15 years (n = 433) who took part in the 2010 Oral Health Survey of the Valencia region, the ICDAS II criteria were employed for diagnosing and coding all the teeth examined. The quantitative BMI values on a continuous scale were grouped into 3 categories (normal weight, overweight, obese) based on a table adjusted for age and gender. The highest-ranking occupation of the parents was taken to indicate the social class o…

Orthodontic treatment stability predictors: A retrospective longitudinal study

ABSTRACTObjective: To examine medium- to long-term orthodontic treatment stability and its possible association with certain variables.Materials and Methods: In a retrospective longitudinal study of 70 postretention patients, the Peer Assessment Rating (PAR) index was measured at the start (T1) and end (T2) of treatment and between 4 and 10 years afterwards (T3). The stability was considered absolute when the T2 and T3 values were identical and relative when the difference was within the ±5 range.Results: Among the 70 patients, 65.8% were female and 34.2% were male. Their mean age was 14.5 years. The mean treatment length was 2.4 years. The mean retention phase was 3.3 years. The mean pre- …

Efficacy of Computer-Aided Static Navigation Technique on the Accuracy of Endodontic Microsurgery. A Systematic Review and Meta-Analysis

The aim of this systematic review and meta-analysis was to analyze the efficacy of the computer-aided static navigation technique on the accuracy of root apex location in endodontic microsurgery. Material and Methods: A systematic literature review and meta-analysis, based on Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) recommendations, of clinical studies that evaluated the apex location rate of the computer-aided static navigation techniques applied to endodontic microsurgery. A total of four databases were consulted in the literature search: Pubmed-Medline, Scopus, Cochrane, and Web of Science. After eliminating duplicated articles and applying the inclusio…

Relationship between perception of malocclusion and the psychological impact of dental aesthetics in university students.

Introduction and Objectives: The objectives were to assess the relationship between perceived smile aesthetics and perceived psychological impact as measured by the Psychosocial Impact of Dental Aesthetics Questionnaire (PIDAQ), and their own perception of it using the Aesthetic Component of the Index of Orthodontic Treatment Need (IOTN-AC) and a Visual Analog Scale (VAS); relate the IOTN-AC and VAS to the PIDAQ; and study the predictive capacity of the scales for psychological impact. Material and Methods: A cross-sectional study was conducted in 447 college students in Spain and Portugal (average age 20.4 years, 33.1% men and 66.9% women). The online self-completed surveys used the recent…

Titanium plate removal in orthognathic surgery: prevalence, causes and risk factors. A systematic literature review and meta-analysis

The purpose of this review was to analyse the prevalence of titanium plate removal in orthognathic surgery, as well as the causes of plate removal, and to determine the associated risk factors. A thorough search of the PubMed, Scopus, Embase, and Web of Science databases was conducted. The inclusion criteria were studies of adult patients who underwent orthognathic surgery in which monocortical titanium plates and screws were placed. Of the 325 references identified, 19 were included in the qualitative synthesis and meta-analysis. Overall, 13.4% (95% confidence interval (CI) 9.6-18.3%) of the patients required the removal of at least one titanium plate; 9.7% (95% CI 6.3-14.6%) of the plates…

Relación entre la caries, el índice de masa corporal y la clase social en niños españoles

Abstract Objective: To determine the association between caries, body mass index (BMI) and social class in child population of the Valencia region (Spain) at 6, 12 and 15 years, and study. Methods: In a cross sectional study of 1326 children aged 6 (n = 488), 12 (n = 409) and 15 years (n = 433) who took part in the 2010 Oral Health Survey of the Valencia region, the ICDAS II criteria were employed for diagnosing and coding all the teeth examined. The quantitative BMI values on a continuous scale were grouped into 3 categories (normal weight, overweight, obese) based on a table adjusted for age and gender. The highest-ranking occupation of the parents was taken to indicate the social class o…

Use of DIAGNOdent and VistaProof in diagnostic of Pre-Cavitated Caries Lesions—A Systematic Review and Meta-Analysis

Objective: To analyse the published evidence of the validity of DIAGNDOdent and VistaProof in diagnosing carious depths in pre-cavitated lesions. Material and methods: A systematic review was carried out after identifying a total of 184 articles, including 27 concerning the qualitative review and a subsequent meta-analysis. The quality of the studies was evaluated by using the QUADAS-2 tool. Results: For DIAGNOdent, the sensitivity value was 0.77, the specificity value was 0.75 and AUC was 0.81 for the global meta-analyses. In relation to subgroups, the values estimated 0.85, 0.76 and 0.86, respectively, for the in vivo group and 0.71, 0.75 and 0.83 for the in vitro group. For VistaProof, s…

Effect of two whitening agents on the color of composite dental restorations

Background To evaluate color changes to composite resins used to restore extracted teeth compared with composite discs after whitening with two agents: hydrogen peroxide (HP) and carbamide peroxide (CP). Material and methods Ten human molars with class V vestibular and palatine cavity preparation obturated with Vita hybrid nanocomposite were hemisected to obtain 20 specimens assigned randomly to two groups: O1 and O2. Twenty composite discs were divided into two groups: D1 and D2. The groups O1 and D1 were treated with 16% CP, while groups =2 and D2 were treated with 37.5 % HP. Chromaticity coordinates L*, a* and b* were registered using a spectrophotometer. Results Statistically significan…

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 …

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) …

Factors related to the psychological impact of malocclusion in adolescents

AbstractTo study the association between orthodontic treatment need and the psychosocial impact of dental aesthetics in a sample of adolescents, as well as other associated factors. A transversal study was conducted on 1,158 adolescents (12–16 years old) examined at the schools selected for the 2018 epidemiological study on oral health in the Comunidad Valenciana (Spain). The need for orthodontic treatment was determined by DAI and IOTN. The psychosocial impact was established by the Psychosocial Impact of Dental Aesthetics Questionnaire (PIDAQ). Other variables considered were sex, social class, DMFT index and Body-Mass Index, and having previously worn or presently wearing an orthodontic …

Orthodontic treatment need in a 12-year-old population in the Western Sahara.

The aim of this study was to establish orthodontic treatment need according to the Dental Aesthetic Index (DAI) and Aesthetic Component (AC) and Dental Health Component (DHC) of the Index of Orthodontic Treatment Need (IOTN) and to determine its association with gender among Saharan schoolchildren. The study was carried out in accordance with World Health Organization (WHO) recommendations for oral health surveys at 12 years of age. The sample comprised 248 Sahrawi children (135 girls and 113 boys) living in refugee camps in Tindouf, Algeria. None of the children had previously received any orthodontic treatment. A chi-square test was used to analyse the IOTN results by gender, and a Studen…

Periodontal Behavior Around Teeth Prepared with Finishing Line for Restoration with Fixed Prostheses. A Systematic Review and Meta-Analysis

Background: The objective of this systematic review and meta-analysis was to analyze the periodontal behavior around teeth prepared with horizontal finishing crowns supporting fixed metal-ceramic and zirconia full coverage crowns and fixed partial dentures (FDPs). Materials and methods: An electronic search was conducted to locate relevant clinical trials in four databases: PubMed, Embase, Cochrane, and Scopus. A manual search was made in the reference sections of the articles identified for any additional articles. No restrictions were applied regarding year of publication or language. The following variables were considered in quantitative and qualitative analysis: probing pocket depth (P…

Effect of rapid maxillary expansion on sleep apnea-hypopnea syndrome in growing patients. A meta-analysis.

Background Changes produced in the upper airway after rapid maxillary expansion makes this procedure a therapeutic option for treating sleep apnea-hypopnea syndrome (SAHS) in children. The objective of this systematic review and meta-analysis was to analyze the evidence available for the effects of rapid maxillary expansion (RME) on SAHS, analyzing changes produced in oximetric variables: apnea-hypopnea index (AHI); oxygen saturation (SO2); sleep efficiency (SE), total sleep time (TST), percentage of rapid eye movement (REM) phase; and arousal index (AI). Material and Methods An electronic search was conducted in the PubMed, Scopus, Embase, and Cochrane databases, and in grey literature (Op…

Wear in Antagonist Teeth Produced by Monolithic Zirconia Crowns: A Systematic Review and Meta-Analysis

Background: The aim of this systematic review and meta-analysis was to determine the wear sustained in the natural antagonist tooth in cases of full-coverage fixed-base prosthetic restorations or monolithic zirconia tooth-supported crowns, as well as to determine the wear in the restoration itself, both in the short- and medium-term and considering the factors that may influence wear. Material and methods: A systematic literature review and meta-analysis, based on Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) recommendations, of clinical studies that evaluated wear in antagonist teeth in relation to fixed-prosthesis monolithic zirconia crowns. A total of 5 data…

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 t…

Diagnostic Validity of Digital Imaging Fiber-Optic Transillumination (DIFOTI) and Near-Infrared Light Transillumination (NILT) for Caries in Dentine.

The objective of the study is to analyse the available evidence for the validity of the transillumination method in the diagnosis of interproximal caries. Bibliographic searches were carried out in three data bases (PubMed, Embase, Scopus) with the key words &#8220;Transillumination AND caries&#8221;. A total of 11 studies were selected for the qualitative analysis and meta-analysis. In the qualitative analysis, both in vivo and in vitro studies were included. The gold standards were tomography, digital radiography, and clinical visual diagnosis. The meta-analysis determined the sensitivity, specificity, and area below the ROC curve relative to the transillumination method in the diagnosis …

Letters From Our Readers

Caries and dental fluorosis in a western Saharan population of refugee children

The aim of this study was to investigate the relationship between dental fluorosis and dental caries among western Saharan refugee children. The western Saharan child population is characterized by adverse living conditions, an unbalanced diet, poor oral hygiene habits, and a concentration of fluoride in the drinking water of around 2 p.p.m. (2 mg l(-1)). A sample consisting of 360 children, 6-7 yr of age, and 212 children, 11-13 yr of age, was obtained from four refugee camps (Smara, Awsard, El-Aaiun, and 27-February) situated in the vicinity of Tindouf (southern Algeria). The children were examined using the World Health Organization criteria for caries diagnosis and Dean's index for fluo…

Degree of severity of molar incisor hypomineralization and its relation to dental caries

AbstractMolar incisor hypomineralization is a developmental defect of dental enamel associated with rapid caries progression. In order to discover whether molar incisor hypomineralization predisposes to dental caries, a cross-sectional cohort study was conducted in a sample of 414 children aged between eight and nine years. It was found that 24.2% of the children presented molar incisor hypomineralization. Of these, 72% had a mild form and 28% a severe form. Caries prevalence was greater among the children with severe form (60.7%) than in those with mild form (43.1%) or no molar incisor hypomineralization (45.5%). The caries indices were higher in out molar incisor hypomineralization (1.18)…

Alveolar bone height and thickness assessed by CBCT

Abstract Objectives To seek information regarding the relationship between the quantity of alveolar bone and the angle and sagittal position of the incisors. This was to be further determined in relation to the basal bones and facial pattern with the aim of establishing a predictive model based on the study of a lateral cephalogram. Methods The distance from the cemento-enamel junction to the labial alveolar crest and the bone thickness half-way along the root of the most prominent upper and lower incisor were measured in a sample of 100 cone beam computed tomography (CBCT) scans of patients aged between 15 and 34 years. Lateral cephalograms of the patients were extracted from the scans and…

Does breastfeeding have a long-term positive effect on dental occlusion?

Background Breastfeeding produces beneficial effects on a baby's early growth and development, and general well-being. Some studies have associated breastfeeding with better occlusal development. The aim of this study was to assess the long-term effect of breastfeeding on occlusal development in children. Material and methods A retrospective cohort study was conducted to evaluate the occlusions of 320 children belonging to the Spanish INMA Project cohort, monitored from gestation onwards. The association between the duration of breastfeeding and different occlusal traits in mixed dentition (overjet, overbite, openbite, midline displacement, incisor crowding, incisor spacing, diastema, maxim…

Psychosocial impact of malocclusion in Spanish adolescents

Objective: To evaluate the psychosocial impact of malocclusion, determine its relationship with the severity of malocclusion, and assess the influence of gender and social class on this relationship in adolescents. Methods: A random sample of 627 Spanish adolescents aged 12 - 15 years underwent intraoral examinations by 3 calibrated examiners (intraexaminer and interexaminer kappa > 0.85) at their schools. Psychosocial impact was measured through a self-rated Psychosocial Impact of Dental Aesthetics Questionnaire (PIDAQ). The severity of malocclusion was measured by the Index of Orthodontic Treatment Need (IOTN). Gender and social class were also recorded. Results: The total PIDAQ score and…

Relationship between the psychosocial impact of dental aesthetics and perfectionism and self-esteem

Background Awareness of the influence of personality traits such as self-esteem and perfectionism on the aesthetic self-image can help clinicians to improve their patients' satisfaction and quality of life. The main objective of this study was to examine the relationship between self-esteem, perfectionism and the psychosocial impact of dental aesthetics, and their association with gender. Material and methods A descriptive-analytical cross-sectional study was conducted in a sample of 301 students of the Faculty of Medicine and Dentistry of the University of Valencia, aged between 18 and 30 years. Each participant was asked to complete a survey comprising three questionnaires: PIDAQ (Psychos…

Association between passive tobacco exposure and caries in children and adolescents. A systematic review and meta-analysis.

To examine the available evidence on the association between exposure to tobacco use in the womb and in infancy and the presence of caries in primary and permanent dentition in children and adolescents. A systematic review was conducted through searches in 4 data bases (Pubmed, Scopus, Embase and Web of Science), complemented by hand-searching. Of the 559 articles identified, 400 were duplicates. Finally, 28 articles were included in the qualitative review and 21 in the meta-analysis. Their quality was assessed using the Newcastle-Ottawa scale. The quality was medium in 44% of the articles included and high in 56%. The overall meta-analysis gave a significant odds ratio (OR = 1.53, 95% conf…

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 differe…

The effects of lasers on bond strength to ceramic materials: A systematic review and meta-analysis

Lasers have recently been introduced as an alternative means of conditioning dental ceramic surfaces in order to enhance their adhesive strength to cements and other materials. The present systematic review and meta-analysis aimed to review and quantitatively analyze the available literature in order to determine which bond protocols and laser types are the most effective. A search was conducted in the Pubmed, Embase and Scopus databases for papers published up to April 2017. PRISMA guidelines for systematic review and meta-analysis were followed. Fifty-two papers were eligible for inclusion in the review. Twenty-five studies were synthesized quantitatively. Lasers were found to increase bo…

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

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).Cross-sectional study.School of Dentistry, University of Valencia.A total of 1086 children: 321 aged 9, 397 aged 12 and 368 aged 15.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.Overbite and inter-incisal diastema were the occlusal features that presented significant differences between the three groups, diminishing with age. Trea…

Effect of per Capita Income on the Relationship between Periodontal Disease during Pregnancy and the Risk of Preterm Birth and Low Birth Weight Newborn. Systematic Review and Meta-Analysis

This work analyzed the available evidence in the scientific literature about the risk of preterm birth and/or giving birth to low birth weight newborns in pregnant women with periodontal disease. A systematic search was carried out in three databases for observational cohort studies that related periodontal disease in pregnant women with the risk of preterm delivery and/or low birth weight, and that gave their results in relative risk (RR) values. Eleven articles were found, meeting the inclusion criteria. Statistically significant values were obtained regarding the risk of preterm birth in pregnant women with periodontitis (RR = 1.67 (1.17–2.38), 95% confidence interval (CI)), and low birt…

Impact of functional mandibular advancement appliances on the temporomandibular joint : a systematic review

Background Although many orthodontists have no doubts about the effectiveness of functional appliances for mandibular advancement, the impact on the temporomandibular joint (TMJ) is still in dispute. The objective of this systematic review is to examine the main effects on the TMJ of using functional appliances, both in healthy patients and in patients with a pre-existing disorder. Material and Methods A systematic review of the literature was conducted in accordance with the PRISMA guidelines. Only systematic reviews, meta-analyses, randomized clinical trials (RCTs), case-control studies and cohort studies were included. A detailed language-independent electronic search was conducted in th…

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

Summary 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 int…

Oral health-related quality of life of adolescents after orthodontic treatment. A systematic review

Background Given the prevalence of malocclusions and the impact they have on oral health, patients' quality of life assessments provide useful information, not only in terms of patients' needs and expectations before treatment, but about whether or not orthodontic treatments meet them satisfactorily. The present systematic review was carried out to evaluate changes in the quality of life of adolescent patients after orthodontic treatment. Material and methods An electronic search was conducted in the Pubmed, Embase, Cochrane and Scopus databases. The review followed PRISMA guidelines for systematic reviews and meta-analyses. Results Of the 817 studies identified in the initial search, only …

Changes in the alveolar bone thickness of maxillary incisors after orthodontic treatment involving extractions ? A systematic review and meta-analysis

Background Orthodontic treatment involving en-masse retraction of incisors following premolar extractions, may induce morphological alterations of the alveolar bone surrounding the anterior teeth. Objective To assess changes in alveolar bone thickness around the incisors of extraction patients measured with CBCT. Material and methods An electronic search was conducted in PubMed, Scopus, Embase and Cochrane Library, using search terms, with no limitation on publication date, up to April 2018. The articles selected for analysis included randomized controlled trials, case-control studies and cohort studies of patients treated with fixed appliances and premolar extractions, which had measured a…

Survival Rate and Prosthetic and Sinus Complications of Zygomatic Dental Implants for the Rehabilitation of the Atrophic Edentulous Maxilla: A Systematic Review and Meta-Analysis

Simple Summary Zygomatic dental implants have been proposed as an alternative to atrophic total edentulous maxillae rehabilitation with the necessity of bone grafting procedures. However, surgical, prosthetic, and maxillary sinus complications have been associated with this surgical procedure. Therefore, it is necessary to produce a systematic review and meta-analysis that provides evidence associated with the prognosis when using zygomatic dental implants as an alternative to atrophic total edentulous maxillae rehabilitation. Abstract The aim of this systematic review and meta-analysis was to analyze and compare the survival rate and prosthetic and sinus complications of zygomatic dental i…

Encuesta sobre hábitos higiénicos orales en la población adolescente de la Comunidad Valenciana (2004)

espanolIntroduccion: (fundamento y objetivo): Coincidiendo con el estudio epidemiologico de la Comunidad Valenciana 2004, se ha realizado una encuesta de habitos para valorar la evolucion en el periodo 1998-2004. Pacientes y metodo: La encuesta fue contestada por una muestra seleccionada al azar de 478 escolares de 12 anos y 401 de 15-16 anos. Resultados: El cepillado diario mas de una vez al dia fue realizado por el 52,3% de los ninos y una vez al dia por el 27,3%. Un 3% no se cepilla nunca y un 15,7% lo hace de vez en cuando. Un 51,4% ha ido al dentista en los ultimos seis meses, un 20,1% lo hizo entre los seis meses y el ano, y el 7,6% no ha ido nunca al dentista. El 56,7% ha hecho enjua…

Differences in psychological traits between lingual and labial orthodontic patients: perfectionism, body image, and the impact of dental esthetics.

OBJECTIVE: To examine some of the patients' psychological traits in relation to their levels of perfectionism and their body image, and to discover whether these differ between lingual and labial orthodontic patients. MATERIALS AND METHODS: A cross-sectional study was designed with a consecutive sample of 80 patients attending a private orthodontic office. Three questionnaires were used to assess the patients' body image and level of perfectionism. The mean age was 33 years. The men numbered 32 and the women 48. The validated Spanish version of the Psychosocial Impact of Dental Aesthetic Questionnaire (PIDAQ) was used to assess the psychosocial impact of their dental esthetics. The Multidim…

Effectiveness of interceptive treatment of class III malocclusions with skeletal anchorage: A systematic review and meta-analysis

Recently, new strategies for treating class III malocclusions have appeared. Skeletal anchorage appears to reduce the dentoalveolar effects while maximising the orthopaedic effect in growing patients. The purpose of this systematic review and meta-analysis is to examine the effectiveness of bone anchorage devices for interceptive treatment of skeletal class III malocclusions. Searches were made in the Pubmed, Embase, Scopus and Cochrane databases, as well as in a grey literature database, and were complemented by hand-searching. The criteria for eligibility were: patients who had undergone orthodontic treatment with skeletal anchorage (miniplates and miniscrews). Patients with syndromes or …

Factors associated with edentulousness in an elderly population in Valencia (Spain)

Objective: To determine the prevalence of edentulism and its association with various socioeconomic factors and oral health habits in the population aged 65-74 years old in the region of Valencia. Methods: A cross sectional study was designed. Thirty-four primary health centers and five nursing homes were chosen at random in the region of Valencia (10-15 voluntary participants per sampling point). Clinical examinations were carried out by three calibrated dentists (kappa&gt;0.85) in the same centers. The total sample consisted of 531 individuals (235 men and 296 women). Results: The percentage of toothlessness was 20.7% and the mean number of natural teeth present was 14.92. The prevalence …

Streptococcus mutans and Streptococcus sobrinus detection by Polymerase Chain Reaction and their relation to dental caries in 12 and 15 year-old schoolchildren in Valencia (Spain).

A cross-sectional study was carried out to determine the prevalence of Streptococcus mutans and Streptococcus sobrinus and the association of the two in a random sample (n=614) of the child population of the region of Valencia (Spain). Saliva samples were analyzed by the quantitative polymerase chain reaction (PCR) method to study the relation of these bacteria to caries prevalence and the DMFT index. The prevalence of S. mutans was 35.4% at age 12 and 22.9% at age 15, that of S. sobrinus 18.9% and 8.4% and that of the S. mutans-S. sobrinus association 18.2% and 6.8% respectively. At both 12 and 15 years of age, the caries prevalence rates were lower in the Streptococcus-free group of child…

Socioeconomic factors and severity of periodontal disease in adults (35-44 years). A cross sectional study

Background Periodontal disease or periodontitis is an inflammatory disease with a hight prevalence. According to the last oral health survey of the Spanish population, between 24% and 37% of Spaniards aged over 35 years have periodontitis and 6% to 10% of the adult population have deep periodontal pockets. The aim of this study was to determine the association between risk factors and the presence of periodontal pockets in the adult population. Material and methods A cross sectional or prevalence study of a representative sample of the adult population of the Valencia region was designed. The sample was recruited at 35 health centres, The study was conducted in November and December 2006 un…

Orthodontic treatment need in Spanish schoolchildren: an epidemiological study using the Index of Orthodontic Treatment Need

SUMMARY The aim of this study was to determine the prevalence of malocclusion and orthodontic treatment need in 12- to 16-year-old Spanish schoolchildren using the aesthetic component (AC) and Dental Health Component (DHC) of the Index of Orthodontic Treatment Need (IOTN) and to analyse the relationship with gender and age. The study followed the World Health Organization recommendations for oral health surveys. The sample comprised 655 schoolchildren (306 males and 349 females) who had not undergone orthodontic treatment, divided into two groups: 363 12-year-olds and 292 15- to 16-yearolds, out of a representative sample of the school population of the Valencian Community. The IOTN results…

Oxidative Stress Parameters in Saliva and Its Association with Periodontal Disease and Types of Bacteria

Objective. To determine the association between oxidative stress parameters with periodontal disease, bleeding, and the presence of different periodontal bacteria.Methods. A cross-sectional study in a sample of eighty-six patients, divided into three groups depending on their periodontal status. Thirty-three with chronic periodontitis, sixteen with gingivitis, and thirty-seven with periodontal healthy as control. Oxidative stress biomarkers (8-OHdG and MDA), total antioxidant capacity (TAOC), and the activity of two antioxidant enzymes (GPx and SOD) were determined in saliva. Subgingival plaque samples were obtained from the deepest periodontal pocket and PCR was used to determine the prese…

Impact of Bimaxillary Advancement Surgery on the Upper Airway and on Obstructive Sleep Apnea Syndrome: a Meta-Analysis

AbstractUpper airway changes following bimaxillary advancement surgery to treat obstructive sleep apnea syndrome remain controversial. The main objective of this systematic review and meta-analysis was to investigate the effects of bimaxillary advancement surgery on the upper airway (UA) of obstructive sleep apnea syndrome patients through examining changes three-dimensionally in vertical and supine position and through changes in oximetric variables (AHI, RDI, O2 Sat) and in the quality of life measured by the Epworth sleepiness scale (ESS). A thorough search of the PubMed, Scopus, Embase and Cochrane databases and a grey literature search (Opengrey) were conducted. No limit was placed on …

Influence of the chemical composition of monolithic zirconia on its optical and mechanical properties. Systematic review and meta-regression.

Este artículo se encuentra disponible en la siguiente URL: https://www.jstage.jst.go.jp/article/jpr/66/2/66_JPR_D_20_00218/_pdf/-char/en Este artículo de investigación pertenece al número especial "Advances in Personalized Nursing Care". Purpose: This systematic review set out to investigate the influence of chemical composition and specimen thickness of monolithic zirconia on its optical and mechanical properties. Meta-analysis and meta-regression analyzed the effects of variations in percentages of yttrium, aluminum, and specimen thickness of monolithic zirconia. Study selection: The review followed recommendations put forward in the PRISMA checklist. An electronic search for relevant art…

Failure Rate, Marginal Bone Loss, and Pink Esthetic with Socket-Shield Technique for Immediate Dental Implant Placement in the Esthetic Zone. A Systematic Review and Meta-Analysis

Simple Summary The socket-shield technique has been proposed for preserving the bone ridge and surrounding soft tissues with immediate implantation in the extraction socket, maintaining the buccal wall fragment of the dental root. However, the socket-shield technique has not been compared with the conventional technique for immediate dental implant placement in the esthetic zone regarding the failure rate, marginal bone loss, and pink esthetic. Therefore, it is necessary to develop a systematic review and meta-analysis that provides evidence associated with the prognosis when using the socket-shield technique compared to the conventional technique. Abstract Aim: To compare the failure rate,…

Meta-Analysis of the Use of 8-OHdG in Saliva as a Marker of Periodontal Disease.

The objective was to collect the available evidence on oxidative stress marker measurements in periodontal patients, focusing specifically on 8-hydroxy-2′-deoxyguanosine (8-OHdG) as a salivary marker of periodontal disease, and to perform meta-analyses to calculate differences in concentration compared to healthy persons. A systematic search in PubMed, Cochrane Library, Embase, and Scopus identified 81 articles. Of these, 38 were duplicates. After reading the abstracts of the remaining 43, 42 were selected for full-text assessment. Finally, 17 articles were included in the qualitative synthesis. Those excluded were of low quality, did not answer the research question, or did not meet the in…

Orthodontic Treatment Need: An Epidemiological Approach