Review of Etiology of Posterior Open Bite: Is There a Possible Genetic Cause?

Posterior open bite (POB) is one of the most severe malocclusions that can impair patients' masticatory functions, yet it is also a condition that is poorly understood and not well studied. Most reported cases are either sporadic or idiosyncratic with a diverse yet poorly understood etiology. Although primary failure of eruption (PFE), lateral tongue thrust, and certain medical syndromes or pathology of the temporomandibular joints have all been shown to cause POB, the complex interplay of environmental and genetic factors makes its etiopathogenesis a difficult subject to understand and investigate. Here, we provide a comprehensive review of the etiology of posterior open bite. Additionally, a genetic cause for POB is proposed through a report of an apparently non-syndromic familial case series with high POB penetrance across two generations. Further investigations of the gene(s) and mechanism(s) involved can not only provide a unique opportunity to better understand POB and the intricate muscular-occlusal relationship, but also offer powerful insight into the most effective approaches to clinical management of these (and potentially other) malocclusions.

U.S. and Canadian Orthodontic Faculty Professional Satisfaction: A Survey Study.

The aims of this study were to evaluate U.S. and Canadian orthodontic faculty members' degree of job satisfaction and to assess the relationship between job satisfaction and factors such as full-time/part-time status, tenure status, age, and teaching training. This information is needed to set long-term goals for improving the recruitment and retention of full-time and part-time faculty. In August 2016, all members of the Council on Orthodontic Education Society of Educators and faculty members of the American Association of Orthodontists were invited via email to participate in a 34-question survey, which collected demographic data and asked respondents to report their degree of satisfaction on seven factors. Out of 645 individuals invited to participate, 133 completed all items on the survey (response rate 20.6%). The results showed that faculty time commitment, rank/position in the institution, and tenure status affected respondents' levels of satisfaction regarding quantity of clinical time, value placed on teaching by their institution and students, and leadership of their department chair. In the open-ended responses, increased compensation, more teaching time, and less administrative activity were the most frequent recommendations to improve satisfaction levels. About half (52%) of the respondents reported being satisfied with their financial compensation. Respondents whose institutions gave them training opportunities in teaching skills were 4.78 times more satisfied than those not given those opportunities. The results suggest that reduction of administrative workload, creation of meaningful faculty development programs, more feedback and sharing of information about requirements for promotion, and improvement of financial compensation could improve recruitment and retention of orthodontic educators.

Perceptions of chin asymmetries among dental professionals and laypersons.

INTRODUCTION: Previous studies have looked at a variety of dental and facial asymmetries and compared their detection by dental professionals with those of laypersons. However, few studies have analyzed the diagnosis and perception of chin asymmetries. In this study, we assessed whether dental professionals can recognize and diagnose facial asymmetries of the chin better than laypeople. METHODS: Chin asymmetries were analyzed through a series of edited frontal photographs of 2 subjects (male and female). The transverse position of the chin was digitally altered from 0° (no alteration) to 6° (most severe alteration). Participant responses were collected from laypersons (n = 64), nonorthodontist dentists (n = 58), and orthodontists (n = 145). Participants graded the photographs according to esthetic appeal using a visual analog scale. Statistical analysis produced diagnostic threshold levels for identifying chin asymmetries. RESULTS: Nonorthodontist dentists and orthodontists were better able to diagnose transverse chin asymmetry in the female subject at a lower threshold level of 2° of deviation, compared with laypersons at a 3° deviation. Orthodontists could diagnose transverse chin asymmetry in the male subject at a lower threshold level of 1° of deviation, compared with laypersons and nonorthodontist dentists at a 2° deviation. All 3 groups of raters graded very small or no chin asymmetries (1° and 0°) as more attractive, whereas high degrees of chin asymmetries (5° and 6°) were graded as most unattractive by all 3 groups. CONCLUSIONS: Transverse asymmetries of the chin influence the perception of facial attractiveness by laypersons, nonorthodontist dentists, and orthodontists. Subjects with small asymmetries are graded as most attractive, and subjects with large asymmetries are graded as least attractive. Orthodontists were the harshest graders, followed by the nonorthodontist dentists, whereas laypersons were the most lenient. The accuracy of diagnosing chin asymmetries varied among laypersons, nonorthodontist dentists, and orthodontists. Laypersons were the least accurate in diagnosing transverse chin asymmetries in a female subject, and they were just as accurate as nonorthodontist dentists when diagnosing this asymmetry in a male subject. Nonorthodontist dentists were just as accurate as orthodontists when diagnosing transverse chin asymmetries in a female subject, and orthodontists were the most accurate in diagnosing transverse chin asymmetries in a male subject.

Treacher Collins syndrome: a case study.

Treacher Collins syndrome is a disorder of craniofacial development with high penetrance and variable expressivity. Its incidence is approximately 1 in 50,000 live births. In this article, we describe the orthodontic treatment of an 11-year-old boy with Treacher Collins syndrome.

Management of the American Heart Association's guidelines for orthodontic treatment of patients at risk for infective endocarditis.

INTRODUCTION: For over 50 years, the American Heart Association has made recommendations for the prevention of infective endocarditis. The first guidelines were published in 1955; since then, they have been updated 9 times, most recently in 2007. There is still confusion about which orthodontic procedures are most prone to generate bacteremias and lead to infective endocarditis in susceptible patients. The aim of this study was to conduct a survey to determine orthodontists' knowledge, attitudes, and in-office behaviors regarding the American Heart Association's guidelines. METHODS: A 4-page online survey consisting of 3 sections was sent to members of the American Association of Orthodontists by using a random number generator. The first section consisted of demographic information, the second consisted of questions about the respondents' practice characteristics, and the third included questions about the respondents' knowledge and management of the treatment of patients at risk for infective endocarditis. There were 78 responses. RESULTS AND CONCLUSIONS: Orthodontists are screening for cardiac problems in the patient's medical history but to a lesser extent are requesting written medical clearance from the patient's physician before starting orthodontic treatment. Many of the orthodontists surveyed believed that their knowledge of the American Heart Association's guidelines and management of high-risk patients was in the good-to-excellent range. Orthodontists recommend antibiotic prophylaxis most frequently during band placement and removal. Patients at risk for infective endocarditis are somewhat likely to inquire about possible treatment sequelae associated with previous cardiac problems.

Comparison of space analysis evaluations with digital models and plaster dental casts.

INTRODUCTION: Diagnostic measurements have traditionally been made on plaster dental casts. Now, 3-dimensional digital dental models can be used. The purpose of this study was to compare space analysis measurements made on digital models with those from plaster dental casts. METHODS: Two sets of 25 alginate impressions were taken of patients who had a permanent Class I crowded dentition. Each impression was made into a plaster cast and a 3-dimensional virtual orthodontic model (OrthoCad, Cadent, Fairview, NJ). Measurements of tooth widths at their greatest mesiodistal dimension and arch length were recorded for both types of models. Tooth widths were measured on the plaster models with a digital caliper, and arch length was measured with a piece of brass wire and a millimeter ruler. The virtual models were measured by using OrthoCad's dedicated software. The space analysis measurements were calculated for both types of models, and the extrapolated amount of crowding for each type of model was accessed. All measurements were made by 2 examiners. The resulting values were compared with nonparametric statistics, and method errors were calculated. RESULTS: When comparing digitized models with conventional plaster dental study models, we found a slight (0.4 mm) but statistically significant difference in the space analysis measurements on the maxillary models; measurements on the mandibular models were not significantly different. No significant difference was found between the measurements of the 2 examiners. CONCLUSIONS: The accuracy of the software for space analysis evaluation on digital models is clinically acceptable and reproducible when compared with traditional plaster study model analyses.

Accuracy of digital and analogue cephalometric measurements assessed with the sandwich technique.

INTRODUCTION: The purpose of the study was to evaluate the accuracy of cephalometric measurements obtained with digital tracing software compared with equivalent hand-traced measurements. In the sandwich technique, a storage phosphor plate and a conventional radiographic film are placed in the same cassette and exposed simultaneously. The method eliminates positioning errors and potential differences associated with multiple radiographic exposures that affected previous studies. It was used to ensure the equivalence of the digital images to the hard copy radiographs. Cephalometric measurements instead of landmarks were the focus of this investigation in order to acquire data with direct clinical applications. METHODS: The sample consisted of digital and analog radiographic images from 47 patients after orthodontic treatment. Nine cephalometric landmarks were identified and 13 measurements calculated by 1 operator, both manually and with digital tracing software. Measurement error was assessed for each method by duplicating measurements of 25 randomly selected radiographs and by using Pearson's correlation coefficient. A paired t test was used to detect differences between the manual and digital methods. RESULTS: An overall greater variability in the digital cephalometric measurements was found. Differences between the 2 methods for SNA, ANB, S-Go:N-Me, U1/L1, L1-GoGn, and N-ANS:ANS-Me were statistically significant (P < .05). However, only the U1/L1 and S-Go:N-Me measurements showed differences greater than 2 SE (P < .0001). CONCLUSIONS: The 2 tracing methods provide similar clinical results; therefore, efficient digital cephalometric software can be reliably chosen as a routine diagnostic tool. The user-friendly sandwich technique was effective as an option for interoffice communications.

Evaluation of the accuracy of digital model analysis for the American Board of Orthodontics objective grading system for dental casts.

INTRODUCTION: In 1999, after 3 years of field testing, the American Board of Orthodontics (ABO) implemented a grading system for posttreatment orthodontic models and panoramic radiographs, to make the phase III examination both fair and objective. In the ABO's objective grading system, 7 occlusal criteria (tooth alignment, vertical positioning of marginal ridges, buccolingual inclination of posterior teeth, occlusal relationship, occlusal contacts, overjet, and interproximal contacts) are measured on plaster models to assess a patient's final occlusion. To date, no study has evaluated the ABO grading system for use on digital models. The purpose of this study was to determine whether digital models can be used with reasonable accuracy and reliability for assessing patients' final occlusions. METHODS: Plaster and digital (OrthoCAD, Cadent Inc, Carlstadt, NJ) posttreatment models of 24 patients were gathered from the postgraduate orthodontic clinic at Columbia University School of Dental and Oral Surgery. The plaster models were scored by using the ABO measuring gauge and the 7 criteria of the ABO grading system. A second analysis was done on the digital models. To determine interexaminer error, a fourth-year dental student at Columbia University served as a second examiner and repeated all the analyses. RESULTS: The means of the total score and those for marginal ridges, occlusal contacts, occlusal relationships, overjet, and interproximal contacts were not significantly different between plaster and digital models. However, the means for alignment and buccolingual inclination were significantly different. In addition, the scorings of 2 examiners differed for the 2 methods. CONCLUSIONS: This finding suggests that alignment and buccolingual inclination should be reevaluated with both methods, and adequate calibration of the examiners is essential to achieve repeatability in both methods. Digital models might be acceptable for use in the ABO model examination.

The American Board of Orthodontics: Diplomate recertification.

Although some specialty certifying boards began recommending or requiring recertification of their "boarded" specialists as early as 1986, recertification is a relatively new concept for the specialty of orthodontics. In the mid 1990s, the American Board of Orthodontics (ABO) recognized that many other medical and dental specialty boards had already established voluntary or mandatory recertification policies and decided to establish its own time-limited certifying policy. After a series of field tests involving former directors, council members of the College of Diplomates of the ABO, and volunteer diplomates, the ABO instituted a recertification policy for candidates who applied for initial certification after January 1, 1998. Since then, the total number of diplomates who have been recertified has steadily increased. Surveys of successfully recertified diplomates reflect a positive feeling about the process. When medical and dental specialists are expected to be more accountable, recertification has been shown to be a valid method to help ensure continued competency. The ABO believes that the formulation of educational and certifying processes to document a diplomate's clinical competency throughout his or her career will help to serve the public welfare. The ABO is attempting to make initial certification and periodic recertification attainable for more orthodontists and, in so doing, to provide a standard by which we exist as a specialty.

The ABO discrepancy index: a measure of case complexity.

A criterion for determining the acceptability of a case presented for the American Board of Orthodontics (ABO) Phase III clinical examination is case difficulty. Case difficulty can often be subjective; however, it is related to case complexity, which can be quantifiable. Over the past 5 years, the ABO has developed and field-tested a discrepancy index, made up of various clinical entities that are measurable and have generally accepted norms. These entities summarize the clinical features of a patient's condition with a quantifiable, objective list of target disorders that represent the common elements of an orthodontic diagnosis: overjet, overbite, anterior open bite, lateral open bite, crowding, occlusion, lingual posterior crossbite, buccal posterior crossbite, ANB angle, IMPA, and SN-GoGn angle. The greater the number of these conditions in a patient, the greater the complexity and the greater the challenge to the orthodontist. The ABO is considering several options for applying the discrepancy index to the Phase III clinical examination.

Comparison of measurements made on digital and plaster models.

Measuring plaster models by hand is the traditional method of assessing malocclusion. Recent technologic advances now allow the models to be digitized, measured with software tools, stored electronically, and retrieved with a computer. OrthoCAD (Cadent, Fairview, NJ) performs this service. The purpose of this study was to evaluate the reliability of the OrthoCAD system. Two independent examiners measured tooth size, overbite, and overjet on both digital and plaster models. The results were compared, and interexaminer reliability was assessed. The study sample consisted of 76 randomly selected pretreatment patients. The results showed a statistically significant difference between the 2 groups for tooth size and overbite, with the digital measurements smaller than the manual measurements. However, the magnitude of these differences ranged from 0.16 mm to 0.49 mm and can be considered clinically not relevant. No difference was found between the 2 groups in the measurement of overjet. Interexaminer reliability was consistent for both the plaster and the digital models.