Perspectives
Oral Pathology in the Dental Curriculum: A Guide on What to Teach Mark R. Darling, B.Ch.D., M.Sc. (Dent), M.Sc. (Med), M.Ch.D.; Tom D. Daley, D.D.S., M.Sc., F.R.C.D. (C) Abstract: There has been considerable disagreement among educators on the topics and details of topics that should be included in the teaching of oral pathology to dental students and graduate students in dental specialties. Various authorities have recommended core curricula that range from comprehensive teaching of eighteen categories, each with up to nine subheadings, covering hundreds of entities, to as few as approximately fifty of the most common lesions that affect the oral and maxillofacial region. This article offers a curriculum planning model designed to help faculty make decisions about course content and emphases. The model allows instructors to assess content relevance and priority based on three criteria: 1) commonness, 2) uniqueness, and 3) significance of diseases and conditions. The product of this decision-making process is a relevance score that can serve as a guideline for the choice and details of topics to be included in oral pathology courses. Dr. Darling is Assistant Professor and Dr. Daley is Professor—both in the Division of Oral Pathology, Department of Pathology, University of Western Ontario. Direct correspondence to Dr. Tom Daley, Department of Pathology, University of Western Ontario, London, Ontario, Canada N6A 5C1; 519-661-2111, ext. 86405 phone; 519-850-2926 fax;
[email protected]. Key words: oral pathology curriculum Submitted 12/16/05; accepted 1/10/06
A
major challenge confronting educators in oral pathology today is what to teach undergraduate and graduate students in dental schools so that the curriculum is relevant to a practicing dentist or dental specialist. This complex issue not only involves the opinions of oral pathology educators but also includes the opinions of dental graduates, educators in other dental disciplines outside of oral pathology, and students in dental programs. On behalf of the American Association of Dental Schools (AADS; now American Dental Education Association, ADEA), Zunt chaired a committee that included oral pathologists representing one Canadian and seven American dental schools to review and develop curriculum guidelines for predoctoral oral pathology course content.1 These guidelines, which were a revision of those published in the Journal of Dental Education in 1985,2 were approved by AADS and published in 1992.1 The committee recommended a core curriculum outline for oral pathology that consisted of eighteen topics: 1. developmental disturbances of oral and paraoral structures, 2. benign and malignant nonodontogenic tumors of the oral cavity,
April 2006
■
Journal of Dental Education
3. 4. 5. 6.
odontogenic and nonodontogenic cysts, odontogenic tumors, regressive alterations of the teeth, infections and infectious-like conditions of the oral regions, 7. dental caries, 8. pulp and periapical tissue diseases, 9. spread of oral infection, 10. physical and chemical injuries of the oral cavity, 11. healing of oral wounds, 12. oral aspects of metabolic disease, 13. bone and joint disease, 14. blood and blood-forming organ disease, 15. periodontium diseases, 16. skin and mucocutaneous diseases, 17. nerve diseases, and 18. muscle diseases. Each of these categories was further subdivided, and in many instances, each subdivision included a number of unlisted specific entities. For example, in topic area #6 in the preceding list, “Infections and Infectious-Like Conditions of the Oral Regions,” the committee listed “Viral” as a subcategory that contained many specific entities including infections by various herpes viruses, various hu-
355
man papilloma viruses, and human immunodeficiency virus. Consequently, the AADS recommendations are extremely comprehensive. Some subcategories included entities, such as “Myesthenias,” that the practicing dentist or dental specialist is very unlikely to encounter. Other categories in the 1992 curriculum guidelines, such as “Healing of Oral Wounds,” may be argued to be in the realm of physiology rather than oral pathology. Although the thoroughness of the committee is to be commended, the list of oral pathology topics arguably may be better suited for a graduate program in oral pathology than for undergraduate dental students destined to become general dentists. Further, the only apparent rationale for this large topic base encompassing hundreds of entities is that these conditions occur in, or may affect, the oral cavity. There is not universal acceptance of the 1992 oral pathology curriculum guidelines among oral pathologists in U.S. dental schools. In his editorial, Allen alluded to a discussion on the Bulletin Board of Oral Pathology in which different opinions about what should be taught in undergraduate oral pathology were expressed.3 Allen noted that a “laundry list of every possible lesion” does not allow the dental student to discriminate between common and uncommon diseases—conditions likely to be encountered and not likely to be encountered in a general dental practice. Allen and his colleagues at The Ohio State University College of Dentistry emphasize the “50 or so” most common conditions that the student is likely to encounter in a dental career. The dentist encountering any other, less common lesion is taught to refer the patient to an oral and maxillofacial pathologist. Lingen4 agreed with Allen, suggesting that the memorization of long lists of lesions, many of which would never be encountered by the dentist, was unproductive. However, Summerlin5 disagreed. He pointed out that teachers of oral pathology are ultimately responsible to the patient, who has the right to expect dentists to have a broad knowledge base that extends beyond the most common oral lesions or conditions. Odell et al.6 also suggested that the AADS recommendations were too extensive and incompatible with modern concepts of dental education in the United Kingdom. They recommended a minimum curriculum with six major topic areas: general topics, disorders of the teeth, disorders of the tooth supporting structures, disorders of the oral mucosa, disorders of and within facial and jaw bones, and salivary gland disease. Each of these was divided
356
and, often, further subdivided into specific topics similar to, but less comprehensive, than the AADS guidelines. In an attempt to resolve the disagreement among oral pathology educators, we propose a model that may offer some degree of objectivity in determining what to teach in oral pathology. Since some subjectivity is inevitable, we believe that the model allows flexibility yet consistency in a logical approach to topic selection.
Methods Allen noted that common oral conditions should be taught and based the Ohio State curriculum on this concept.3 He reasoned that other, less common conditions could be referred to a local oral pathologist. This concept is reasonable, as long as there is a local oral pathologist available, but in areas where patient access to specialists is limited or nonexistent, the general dentist is responsible for the diagnosis of a broader range of conditions, as suggested by Summerlin.5 Consequently, commonness alone is not a sufficient criterion on which to base topic selection for a course. Odell et al. recognized that the significance for health of a disease or condition was also an important criterion.6 We agree that dental students should learn conditions that affect the oral cavity with significant consequences with respect to acute or chronic patient morbidity or potential patient mortality. For example, students must learn about melanoma because it may present orally and may be life-threatening to the patient, although it is neither common nor unique to the oral cavity. We suggest a third criterion—uniqueness of the condition or disease—because it occurs in the oral cavity and may not be well known by other health care providers. For example, diseases of the teeth and tumors and cysts of the odontogenic apparatus are largely in the knowledge base of the dental profession and are consequently our responsibility, but are not well understood by patients and are not in the spectrum of training for other health professionals. A general dentist may be sought by patients and other health care professionals for information or consultation concerning these conditions. Circles in a Venn diagram can represent domains, one for each of the three criteria, and a fourth domain that represents an area of overlap (Figure 1). The diameter of each circle may vary according to
Journal of Dental Education ■ Volume 70, Number 4
the number of entities it contains. Generally, most topics that fall within one of the four zones of intersection should be taught in the oral pathology curriculum. However, the selection of topics may be refined further by assigning a relevance score. Topics in each domain are assigned a score from 0 to 3 according to the criteria listed below. This will often be a subjective rating, but objective criteria such as incidence rates or prevalence rates may be used as objective indicators.
significant 2 1
common
4
Domain 1: Commonness 3
Score 0— never or rarely occurs in the oral and maxillofacial area (omfa)
unique
1— uncommonly occurs in the omfa 2— sometimes occurs in the omfa 3— commonly occurs in the omfa Domain 2: Significance
Figure 1. Topics guideline for dental school oral pathology courses
Score 0— trivial, of no clinical significance 1— may cause mild to moderate morbidity 2— causes significant morbidity 3— potentially fatal Domain 3: Uniqueness Score 0— a condition or lesion that is not seen and does not affect the omfa
quently, the critical score for topic inclusion would be higher; thus, fewer entities would be taught. Alternately, oral surgeons, oral radiologists, and oral pathologists are heavily involved in the diagnosis and treatment of a broad range of oral conditions and diseases. Consequently, the critical score for topic inclusion would be lower, and these specialties would have more entities included in their courses.
1— when a lesion or condition occurs, it uncommonly affects the omfa 2— when a lesion or condition occurs, it is usually in the omfa 3— exclusively an oral condition or lesion The relevance score is the sum of scores of the three domains (range 0 to 9). Table 1 lists a number of entities to which we have assigned a relevance score appropriate to our patient population. The critical relevance score (at and above which the topic is included in the curriculum) may vary depending on the target classes. Dental specialties do not share a similar need for depth or breadth of knowledge in oral pathology because of the nature of the specialty involved. For example, prosthodontists and endodontists are not primary screeners like the general dentist, nor do they deal with the diagnosis and treatment of a large variety of oral diseases. ConseApril 2006
■
Journal of Dental Education
Table 1. Recommended critical relevance scores for dental trainees Field Anesthesiology Orthodontics Dental Public Health Prosthodontics Endodontics General Dentistry Periodontics Oral and Maxillofacial Surgery Oral Radiology Pediatric Dentistry Oral Medicine Oral Pathology
Recommended Critical Relevance Scores 5 6 4 6 6 4 3 3 3 3 2 1
Any score of 4 or above is considered relevant to the practice of general dentistry and should be included in the topic selection.
357
Discussion This model refutes the concept that all diseases must be taught and supports the concept that there should be some logical basis for the selection of topics to be learned by dental trainees. The general dentist is a primary screener and must therefore have a relatively broad, if not too in-depth, knowledge of
oral diseases. A general understanding of these conditions is needed to allow the practitioner to know when to refer, when to treat, and how to treat the patient. As indicated in Table 1, we suggest a critical score of 4 for the general dentist. Any score of 4 or above is considered relevant to the practice of general dentistry and should be included in the topic selection. Significantly, all of the diseases listed in Table 2 fall into the overlap zones illustrated in the
Table 2. Examples of the estimated scores for commonness, uniqueness, and significance used in the selection of topics for the teaching of oral and maxillofacial pathology Topic
Commonness Score
Uniqueness Score
Significance Score
Relevance Score
2 3 0 3 0 3 3 0 1 0 2 0 2 0 0 to 3
3 3 3 3 3 3 3 3 3 3 3 0 3 1 3
3 0 0 0 1 0 0 1 0 1 1 1 1 1 1 to 3
8 6 3 6 4 6 6 4 4 4 6 1 6 2 4 to 9
0
1
1
2
Examples of disease related to dental caries Dental caries Pulpal and periapical sequella Condensing osteitis Proliferative periostitis
3 3 3 0
3 3 3 3
3 3 1 1
9 9 7 4
Examples of diseases of the periodontium Gingivitis Periodontitis Papillon-Lefevre syndrome
3 3 0
3 3 2
3 3 1
9 9 3
Examples of infectious diseases Impetigo Scarlet fever Candidiasis Cryptococcus Herpes Simplex virus Rubella HIV
3 3 3 0 3 3 2
0 2 2 0 2 0 2
0 2 3 1 2 1 3
3 7 8 1 7 4 7
Examples of physical and chemical injuries Morsicatio buccarum Chemotherapy complications Amalgam tattoos
3 0 3
3 1 3
0 3 0
6 4 6
Examples of immunological diseases Aphthous ulceration Behcet’s syndrome Angioedema Orofacial granulomatosis
3 0 1 0
3 0 0 3
1 2 2 1
7 2 3 4
Examples of developmental conditions Cleft lip/palate Commissural lip pits Congenital lip pits Fordyce granules Microglossia Fissured tongue Tori Eagle syndrome Staphne defect Nasolabial cyst Nasopalatine duct cyst Branchial cleft cyst Oral lymphoepithelial cyst Various rare syndromes Anomalies of teeth Various rare syndromes involving teeth anomalies
(continued on next page)
358
Journal of Dental Education ■ Volume 70, Number 4
Table 2. (continued) Topic
Commonness Score
Uniqueness Score
Significance Score
Relevance Score
Examples of epithelial pathology Squamous papilloma Squamous cell carcinoma Actinic cheilitis Melanoma Basal cell carcinoma Oral melanotic macule Spitz nevus
3 3 3 2 3 3 0
2 2 3 1 1 3 0
1 3 1 3 2 1 1
6 8 7 6 6 7 1
Examples of salivary gland pathology Mucocele Cheilitis glandularis Sjogren’s syndrome Pleomorphic adenoma Adenoid cystic carcinoma Salivary duct carcinoma
3 0 3 2 1 0
3 3 2 3 3 3
1 1 2 2 3 3
7 4 7 7 7 6
Examples of soft tissue tumors Fibroma MEN, type 2B Hemangioma Paraganglioma Angiosarcoma Pyogenic granuloma Peripheral giant cell granuloma Synovial sarcoma
3 0 3 0 0 3 3 0
1 1 1 0 0 2 3 0
2 3 2 3 3 1 1 3
6 4 6 3 3 6 7 3
Examples of hematological disorders Lymphoid hyperplasia Anemia Agranulocytosis Leukemia (general aspects) Lymphoma Mycosis fungoides
3 3 0 2 3 0
1 1 0 1 1 0
2 3 2 3 3 3
6 7 2 6 7 3
Examples of bone pathology Osteogenesis imperfecta Paget’s disease of bone Cherubism Fibrous dysplasia Cemento-osseous dysplasias Osteosarcoma Ewing’s sarcoma Metastatic disease to the jaws
0 2 0 1 2 1 0 1
0 2 3 2 3 2 0 2
2 2 2 2 1 3 3 3
2 6 5 5 6 6 3 6
Examples of odontogenic cysts and tumors Dentigerous cyst Calcifying odontogenic cyst Lateral periodontal cyst Ameloblastoma Odontoma, compound Odontogenic myxoma
3 1 2 1 3 1
3 3 3 3 3 3
2 2 2 3 1 2
8 6 7 7 7 6
Examples of dermatologic diseases Lichen planus Mucous membrane pemphigoid Pachyonicia congenital Psoriasis Lupus erythematosus CREST syndrome
3 3 0 2 2 0
2 3 1 0 1 1
2 2 1 1 2 1
7 8 2 3 5 2
1 1 1 1
1 1 2 2
2 2 3 5
Examples of oral manifestations of systemic disease Mucopolysaccharidoses 0 Vitamin C deficiency 0 Addison’s disease 0 Iron deficiency anemia 2
April 2006
■
Journal of Dental Education
359
Venn diagram, since a highest score of 3 in any one domain is insufficient for inclusion. Excluded are such commonly taught entities as congenital lip pits, branchial cleft cysts, impetigo, various fungal infections, Behcet’s syndrome, angioedema, Spitz nevus, a number of unusual neoplasms, osteogenesis imperfecta, and the oral manifestations of many systemic diseases. Table 2 lists our recommended critical relevance scores for dental specialties and, with reference to Table 1, indicates the topics that we would select for each specialty. We recognize that there is still a significant amount of subjectivity in the process of assignment of topic scores in each of the domains. However, this model offers an objective framework designed to reduce the influence of subjectivity and allow the educator to more easily draw final conclusions about topic selection. Furthermore, some degree of subjectivity is encouraged since there is geographic variation in disease incidence and availability of medical care/specialists. Consequently, individuals in different parts of the world would assign different scores based on local data/conditions, resulting in courses that are more customized.
360
Conclusion This article described a semiobjective curriculum planning model to assist educators in the selection of topics to be taught in oral pathology courses for dental trainees. The model reduces subjectivity, while still allowing some variation to accommodate geographical differences.
REFERENCES 1. American Association of Dental Schools. Curriculum guidelines for predoctoral oral pathology. J Dent Educ 1992;56:710-7. 2. American Association of Dental Schools. Curriculum guidelines for pathology and oral pathology. J Dent Educ 1985;49:599-606. 3. Allen CM. Oral and maxillofacial pathology: what should we teach and how should we teach it? (editorial) Oral Surg Oral Med Oral Pathol 1996;82:235. 4. Lingen MW. Teaching oral pathology. Oral Surg Oral Med Oral Pathol 1997;83:308. 5. Summerlin D-J. Teaching oral pathology. Oral Surg Oral Med Oral Pathol 1997;83:308-9. 6. Odell EW, Farthing PM, High A, Potts J, Soames J, Thakker N, et al. British Society for Oral and Maxillofacial Pathology UK: minimum curriculum in oral pathology. Eur J Dent Educ 2004;8:177-84.
Journal of Dental Education ■ Volume 70, Number 4
