The neuroanatomic basis of facial perception and variable facial discrimination ability: implications for orthodontics.

INTRODUCTION: Because of familial, ethnic-racial, cultural, and emotional preferences, achieving common facial understanding among orthodontist, patient, parents, and other health care professionals is a daunting communication challenge. Research into the neuroanatomic basis of human facial perception, including the roles of visual short-term memory and long-term memory, might apply to orthodontic facial learning. METHODS: In this article, we review findings from functional magnetic resonance imaging and electrophysiology studies of the brain during visual perception and mental imaging of faces, and integrate these findings with facial learning needs in orthodontics. RESULTS: Research distinguishes specialized brain areas for whole face and face feature perception, the spatial relationship of face features, and facial memory stores. The right anterior temporal lobe's fusiform face area helps recognize facial identity, whereas the bilateral superior temporal sulcus assists in perception of facial expression. The amygdala, hippocampus, and bilateral inferior occipital gyrus help process familiar, unfamiliar, and famous faces. Because visual perceptual experience and processing are individually variable, along with visual short-term memory and long-term memory capacities, it is likely that facial discrimination ability is variable. CONCLUSIONS: Neuroanatomic research shows that each person's brain is as unique as his or her face. Due to variable neural hard-wiring, what the clinician sees facially might not be what the patient or parent sees, and vice versa. Enhanced facial learning is related to creation of a distinctive mental context associated with a facial stimulus and rich mixing between memory and visual perception. This context can be formed by information from clinical examinations, patient databases, patient-parent facial preference questionnaires, and functional face viewing. The more extensive the long-term memory facial links, the better the person knows the face. Facial discrimination exercises with electronic and hard-copy tools might improve facial learning and should be based on defined facial learning objectives. Tools should use facial prototypes and facial-feature spatial-relationship information, and emphasize categorization of whole faces and facial components. These are proven methods of expert recognition of objects having prototypical spatial configuration.

Renewing professionalism in dental education: overcoming the market environment.

The most important mission of dental education is development of student professionalism. It is only within the context of professionalism that specialized knowledge and technical expertise find meaning. Altruism, integrity, caring, community focus, and commitment to excellence are attributes of professionalism. Its backbone is the obligation of service to people before service to self--a social contract. Professionalism can and should be acquired by targeted interventions, not as an assumed by-product of dental education. Top-down, rule-based professionalism is contrasted with its experience-based, mentor-mediated, socially driven counterpart. Moral principles are inherent in professional development and the professional way of life. Unfortunately, American society, including higher education, glorifies a market mentality centered on expansion and profit. Through formal and hidden curricula, dental schools send mixed messages to students about the importance of professionalism. Institutional consensus on professionalism should be developed among faculty, administration, and students through passionate advocacy and careful analysis of dentistry's moral convictions. The consensus message should communicate to stakeholders that morality and ethics "really count." Maximum student exposure to faculty exemplars, substantial service-learning experiences, and portfolio use are likely to enhance professionalism, which should be measured for every student, every semester, along with faculty and institutional assessment. Research reveals a significant relationship between levels of student moral reasoning and measures of clinical performance and shows that moral reasoning ability can be enhanced in dental students. Valid and reliable surveys exist to assess student moral reasoning. Documented student unprofessional behavior is a predictor of future state professional board disciplinary action against practitioners, along with low admissions test scores and course failures in the first two professional school years. ADEA Policy Statements recognize the importance of professionalism in student development. From day 1 of dental school, faculty and students should have no doubt as to what constitutes acceptable and unacceptable behavior in academic and clinical settings. With education and experience, dental students and dentists are likely to elevate their standards of professionalism.

Current concepts in the biology of orthodontic tooth movement.

Adaptive biochemical response to applied orthodontic force is a highly sophisticated process. Many layers of networked reactions occur in and around periodontal ligament and alveolar bone cells that change mechanical force into molecular events (signal transduction) and orthodontic tooth movement (OTM). Osteoblasts and osteoclasts are sensitive environment-to-genome-to-environment communicators, capable of restoring system homeostasis disturbed by orthodontic mechanics. Five micro-environments are altered by orthodontic force: extracellular matrix, cell membrane, cytoskeleton, nuclear protein matrix, and genome. Gene activation (or suppression) is the point at which input becomes output, and further changes occur in all 5 environments. Hundreds of genes and thousands of proteins participate in OTM. Gene-directed protein synthesis, modification, and integration form the essence of all life processes, including OTM. Bone adaptation to orthodontic force depends on normal osteoblast and osteoclast genes that correctly express needed proteins at the right times and places. Cell membrane receptor-ligand docking is an important initiator of signal transduction and a discovery target for new bone-enhancing drugs. Despite progress in identification of regulatory molecules, the genetic mechanism of "orchestrated synthesis" between different cells, tissues, and systems remains largely unknown. Interpatient variation in mechanobiological response is most likely due to differences in periodontal ligament and bone cell populations, genomes, and protein expression patterns. Discovery of mutations in OTM-associated genes of orthodontic patients, including those regulating osteoclast bone-matrix acidification, chloride channel function, and osteoblast-derived mineral and protein matrices, will permit gene therapy to restore normal matrix and protein synthesis and function. Achieving selectivity in targeting abnormal genes, cells, and tissues is a major obstacle to safe and effective clinical application of gene engineering and stem-cell mediated tissue growth. Orthodontic treatment is likely to evolve into a combination of mechanics and molecular-genetic-cellular interventions: a change from shotgun to tightly focused communication with OTM cells.

Confronting shibboleths of dental education.

Shibboleths are common expressions presented as indisputable truths. When used in educational discussions, they reflect "motherhood and apple pie" viewpoints and tend to bring debate to a halt. Use of shibboleths may precede a desired imposition of "locksteps" in educational programming and are easily perceived as paternalistic by recipients. Nine shibboleths are presented as common beliefs of dental faculty and administrators. Evidence contradicting the veracity of the "obvious truths" is offered. The traditional "splendid isolation" of dentistry contributes to parochialism and belief in false shibboleths. Sound principles of higher and health professions education, student learning, and dental practice apply to dental education as to all health disciplines. Student passivity in dental education is not the best preparation for proficiency in dental practice. The master teacher possesses a repertoire of methodologies specific to meeting defined educational objectives. Active learning experiences bear close resemblances to professional duties and responsibilities and internally motivate future doctors of dental medicine. The difficulty in achieving curricular change leads to curricular entrenchment. Dentistry and dental education should not trade their ethical high ground for the relatively low ethical standards of the business world. Principles of professional ethics should govern relationships between dentists, whether within the dental school workplace or in practice. Suggestions are made on how to confront shibboleths in dental school settings.

Internal dental school environmental factors promoting faculty survival and success.

A career in dental academics offers ample rewards and challenges. To promote successful careers in dental education, prospective and new dental faculty should possess a realistic view of the dental school work environment, akin to the informed consent so valuable to patients and doctors. Self-assessment of personal strengths and weaknesses provides helpful information in matching faculty applicants with appropriate dental schools. Essential prehiring information also includes a written job description detailing duties and responsibilities, professional development opportunities, and job performance evaluation protocol. Prehiring awareness of what constitutes excellence in job performance will aid new faculty in allotting time to productive venues. New faculty should not rely solely on professional expertise to advance careers. Research and regular peer-reviewed publications are necessary elements in academic career success, along with the ability to secure governmental, private foundation, and corporate grant support. Tactful self-promotion and self-definition to the dental school community are faculty responsibilities, along with substantial peer collaboration. The recruitment period is a singular opportunity to secure job benefits and privileges. It is also the time to gain knowledge of institutional culture and assess administrative and faculty willingness to collaborate on teaching, research, professional development, and attainment of change. Powerful people within dental schools and parent institutions may influence faculty careers and should be identified and carefully treated. The time may come to leave one's position for employment at a different dental school or to step down from full-time academics. Nonetheless, the world of dental and health professional education in 2005 is rapidly expanding and offers unlimited opportunities to dedicated, talented, and informed educators.

Dental education and evidence-based educational best practices: bridging the great divide.

Research about educational best practices is negatively perceived by many dental faculty. Separation between teaching and learning strategies commonly employed in dental education and evidence-based educational techniques is real and caused by a variety of factors: the often incomprehensible jargon of educational specialists; traditional academic dominance of research, publication, and grantsmanship in faculty promotions; institutional undervaluing of teaching and the educational process; and departmentalization of dental school governance with resultant narrowness of academic vision. Clinician-dentists hired as dental school faculty may model teaching activities on decades-old personal experiences, ignoring recent educational evidence and the academic culture. Dentistry's twin internal weaknesses--factionalism and parochialism--contribute to academic resistance to change and unwillingness to share power. Dental accreditation is a powerful impetus toward inclusion of best teaching and learning evidence in dental education. This article will describe how the gap between traditional educational strategies and research-based practices can be reduced by several approaches including dental schools' promotion of learning cultures that encourage and reward faculty who earn advanced degrees in education, regular evaluation of teaching by peers and educational consultants with inclusion of the results of these evaluations in promotion and tenure committee deliberations, creating tangible reward systems to recognize and encourage teaching excellence, and basing faculty development programs on adult learning principles. Leadership development should be part of faculty enrichment, as effective administration is essential to dental school mission fulfillment. Finally, faculty who investigate the effectiveness of educational techniques need to make their research more available by publishing it, more understandable by reducing educational jargon, and more relevant to the day-to-day teaching issues that dental school faculty encounter in classrooms, labs, and clinics.

Predicting skeletal maturation using cervical vertebrae.

This study's objective was to familiarize the profession with determining skeletal maturation and skeletal age, and predicting growth potential by using cervical vertebrae images of lateral cephalograms. The investigation was done through repeated evaluations of 30 randomly selected, pretreatment lateral cepaholometric radiographs. The accuracy of determining skeletal age and growth potential with lateral cephalograms was found to be R=0.98 (highly accurate) by statistical analysis.