Journal of the Dental Association of South Africa, 43, 111-114 Pathological conditions detected on panoramic radiographs of two Johannesburg populations. * M.B. Finkelstein, J.F. Lownie and ** P.E. Cleaton-Jones * Division of Maxillo-Facial and Oral Surgery, University of the Witwatersrand ** and MRC / University of the Witwatersrand Dental Research Institute, Johannesburg. Keywords: Radiography, panoramic. SUMMARY In the diagnosis o f pathological lesions o f the oral cavity and surrounding tissues, radiographs are used to supplement clin­ ical examination. In this study the objectives were to describe the prevalence o f pathological conditions in radiographic re­ cords o f a dental school patient population and to compare the prevalence in Caucasoid and Negroid subsamples. One thou­ sand panoramic radiographs were examined for specified tooth and bony lesions. The sample comprised radiographs from 514 Caucasoid and 486 Negroid patients. With regard to what was termed tooth lesions, in all groups missing teeth were the commonest finding, followed by impacted teeth and periapical radiolucencies. Bone lesions in decreasing preva­ lence were residual roots, focal radiopacities and unilocular radiolucencies. When subgroups, by ethnic group and sex, were compared, statistically significant differences in preva­ lence were noted although no consistent pattern emerged. The investigation has shown that screening studies o f filed pano­ ramic radiographs o f South African hospital populations is a useful method for assessing prevalence trends o f defined pa­ thological lesions. OPSOMMING Benewens kliniese ondersoekmetodes word rontgenologiese opnames as hulpmiddel gebruik in die diagnose van patolo- giese letsels van die mond en omringende strukture. Die doel van hierdie ondersoek was om die prevalensie van patologiese toestande, soos waargeneem op rontgenfoto's van die pasien- tebevolking van 'n tandheelkundige opleidingshospitaal, te bcpaal en om die prevalensie in Kaukasier- en Negroiede sub- groepe te vergelyk. Ecnduisend panoramiese rontgenopna- mes van 514 Kaukasiers en 486 Negroiede pasiente is onder­ soek vir die voorkoms van gespesifiseerde tand- en beenlet- sels. Van sogenaamde tandletsels was afwesige tande die al- gemeenste waameming in alle groepe, gevolg deur geimpak- teerde tande en periapikale ontsteking. In dalende orde van voorkoms van beenletsels is die volgende waargeneem: tand- wortelreste, fokale radio-opasiteite en lokulere radiodeur- skynende areas. Vergelyking van subgroepe, verdeel op et- niese en geslagtelike basis, toon statistiesbeduidende verskille in pervalensie maargeen standhoudende patroon is vasgestel nie. Die ondersoek toon dat sifting van geliasseerde panora­ miese rontgenopnames van pasientebevolkings van Suid-Afri- kaanse hospitale ’n nuttige metode bied vir die vasstelling van die voorkomsneigings van sekere patologiese toestande. INTRODUCTION In the diagnosis of disease of the oral cavity, following the re­ cording of a good history and an examination of the entire oral cavity, dental radiographs provide an additional source of information. Several types of radiograph may be used: for example, intra-oral periapical and bitewing radiographs for the diagnosis of periodontal disease and caries as well as oc­ clusal plane radiographs for the diagnosis of unerupted teeth. Panormaic radiographs show an uninterrupted view of the en­ tire maxillary and mandibular region (Updegrave, 1966). This technique does not replace the conventional intra-oral dental film but supplements it as a comprehensive radiograph­ ic survey of the entire dentition and supporting structures (White and Weissmann, 1977; Langland etal, 1982). The ra­ diographs are made using either an intra-oral or an extra-oral source of radiation. The latter type is also termed rotational panoramic radiography (Langland et al, 1982). In the present paper the terms panoramic radiography and panoramic radi­ ograph refer to rotational panoramic radiography. Several screening panoramic radiographic studies have been undertaken. The studies of Meister, Simpson and Davis (1977) on United States airmen; Johnson (1970), Allatar, Baughman and Collett (1980) and Barret, Waters and Griffiths (1984) on hospital populations in the United States and Australia showed clear methodology in contrast to those done by Christen et al (1967), Cuttino et al (1969) and Langland et al (1980) on groups of dentists. In general all these studies showed that impacted and unerupted teeth were the most common finding on all panoramic radiographs. In the case of airmen and dentists, the second most common abnormality was periapical radiolucencies, while in the hospi­ tal populations this was retained roots. Thus a variation in prevalence of various pathological lesions in different popula­ tions does exits. No such reports on general screening studies in South African populations exist although Farman, Joubert and Nortje (1978) have studied the prevalence of focal osteo­ sclerosis and apical periodontal pathoses in European and Cape Coloured hospital populations. We believe that there is a need to determine the prevalence of Journal of the D. A.S.A.—March 1988 M.B. Finkelstein, J.F. Lownie and P.E. Cleaton-Jones radiographically diagnosahle lesions in different populations as an aid to public health service planning. Ideally in such in­ vestigations, radiographs should be taken of subjects random­ ly selected from the general population. It is not acceptable in the RSA to subject persons ro radiation solely for research purposes (World Medical Assembly 1964) thus hospital pop­ ulations within which diagnostic radiographs are made must be used. The aims of the present study were firstly to determine the prevalence of pathological lesions in a series of panoramic ra­ diographs in a hospital population in Johannesburg; and se­ condly to determine whether the prevalence of the lesions in radiographs differ between Caucasoid and Negroid patients. Materials and methods One thousand panoramic radiographs of patients attending the Oral and Dental Teaching Hospital of the Witwatersrand for treatment were examined with the approval of the Universi­ ty's Committee for Research on Human Subjects. In order to obtain a representative sample, every second panoramic ra­ diograph in the hospital files was examined until 1000 had been studied. No selection was made on the basis of clinical diagnosis but to qualify for inclusion in the study the radio­ graph had to be that of a Caucasoid or Negroid (International Dictionary of Medicine and Biology 1986), past the mixed dentition stage, and with at least one permanent tooth present. Since the radiographs are filed by patient number which is the sequence in which patients present to the hospital irrespective of age, sex, or diagnosis, the sample is a random one of a hos­ pital population. For each patient the age, sex, ethnic group and reason for the radiograph were recorded. Each radiograph was examined, without magnification, using a standard viewing box in the horizontal position in order to mimic general dental practice. All the radiographs were examined by one examiner (MBF). Intra-examiner diagnostic reproducibility was checked by re­ examining 25 randomly selected radiographs. On the first examination 148 lesions were diagnosed and on the second 146, identical for lesion type and site to the first viewing, were recorded. This 99 per cent reproducibility was consi-* dered acceptible for the study. Recording sheets were compiled divided into two sections. The first dealt with what were termed tooth lesions: missing teeth, impacted teeth, hypercementosis, periapical radiolu- cencies, fractured teeth and unerupted teeth. In the second section, focal or diffuse radiopacities, unilocular or multil- ocular radiolucencies, mixed radiolucency/radiopacity, odon- tomes, supernumerary teeth, retained roots and radiolucen­ cies related to retained roots were noted. These were termed bone lesions. Definitions used for all the lesions are listed in Table I. The data were analysed using descriptive statistics and the Non-parametric Chi-square test without Yates’ correction (SAS 1985). The test populations for the sub-groupings of the tooth and bone lesions were the total numbers of lesions in each instance, not the numbers of radiographs. For example the total number of tooth lesions among Caucasoids was 3205 and among Negroids was 2548. For bone lesions the numbers w-ere 269 and 363, respectively. The Chi-sqUare tests were only perfonied when a lesion prevalence was 30 or more. The critical level of statistical significance chosen was p<0,05. RESULTS The sample of 1000 patients consisted of 293 male Cauca­ soids, 294 male Negroids, 221 female Caucasoids and 192 fe­ male Negroids. These ranged in age from 11-90 y and most panoramic radiographs had been taken during the third de­ cade in all subgroups. Of the 1000 radiographs examined, 786 showed tooth lesions and there were 130 with bone lesions. In the remainder of this article the denominators for percentage prevalence calculations will be the total numbers of lesions per group and subgroup, not the number of radiographs. Among the tooth lesions, mis­ sing teeth were the common abnormality comprising 3946 (69 per cent), followed by 931 (16 per cent) impacted teeth and 531 (9 per cent) periapical radiolucencies. Of the bone le­ sions there were 484 (75 per cent) residual roots, 81 (13 per cent) focal radiopaque areas and 41 (6 per cent) unilocular radiolucencies. The prevalence of missing teeth differed significantly when all combinations of ethnic group and sex were examined (Fig. 1). The lower prevalence of impacted teeth in females (Fig. 2) was statistically significant as was the lower prevalence in Negroid females as compared to negroid males. All other com­ binations did not show statistically significant differences. Unerupted teeth were significantly more common in Cauca­ soids compared with Negroids and also when males were compared with males and females with females within the ethnic grouping (Fig. 3). The most prevalent bone lesions were residual roots and focal radiopacities. With regard to residual roots, these were signi­ ficantly more common among males compared with females (ethnic groups combined), Negroid females compared with Negroid males and Negroid females compared with Cauca­ soid females (Fig. 4). Focal radiopacities (Fig 5) were signifi­ cantly more frequent among Caucasoids than Negroids and females compared with males of all ethnic groups. No radio­ graphs showed mixed radiolucency/radiopacity or complex odontomes. DISCUSSION Patients attending our dental hospital can be subdivided into three groups. The largest group are those who would not in the first instance consult private practitioners. The next com­ prises University staff and students, while the smallest con­ sists of patients requiring specilized treatment. The results presented in this article are thus comparable only to popula­ tions of similar composition and not to the general population. Comparison is possible with several studies done elsewhere. Johnson (1970) investigated a male population in a United States Veterans hospital. He found unerupted teeth to be most frequent followed by retained roots and periapical radiolucen­ cies, a pattern similar to males in the present study. Another United States hospital population study was that of Allatar et al (1980). In their population the lesions seen in descending prevalence were impacted teeth, retained roots and periapi­ cal radiolucencies. The results of our investigation are simi­ lar. Tydskrif van die T.V.S.A.—Maart 1988 112 Pathology on panoramic radiographs C/N M/F CM CF NM NF CM NM CF NF < 43 0 x 64 5 x 4 8 x- 203 4 x 1610 x 201 D <0 01 p < 0 0 1 p < 0 05 p < 0 0 1 p < 0 0 1 p < 0 01 Figure 1: Prevalence of missing teeth by ethnic group and sex. 191 C N x 40 8 p< 0 0 1 M/F x- 1 7 P >0 05 NS CM CF x 37 p > 0 05 NS NM NF x 0 0 p » 0 0 5 NS CM NM x 33 8 p <001 CF NF x 9 0 p < 0 0* Figure 3: Prevalence of unerupted teeth by ethnic group and sex. C. N M F x 3'5 x- 81 p > 0 05 p < 0 01 NS Figure 5: Prevalence of focal radiopacities by ethnic group and sex. In South Africa, Farman et al (1978) examined prevalences of focal osteosclerosis and apical periodontal pathoses in panoramic radiographs of European and Cape Coloured den­ tal outpatients. Focal osteosclerosis was more frequently seen in their European group and apical periodontal pathoses among the Cape Coloureds. In the present investigation focal radio­ paque areas were more common among Caucasoids but api­ cal periodontal pathoses showed similar prevalences among Caucasoids and Negroids. The absolute prevalence of focal radiopacities in the present study was approximately half that seen in the European group. 592 C N M F x 1 5 x 94 P > 0 05 p < 0 01 NS CM CF x 2 4 p >0 05 NS NM NF x 8 6 p < 0 0 1 C M NM x 01 p > 0 05 N S CF NF x 30 p > 0 05 N S Figure 2: Prevalence of impacted teeth by ethnic group and sex. 258 C/N M/F CM/CF NM/NF CM , NM CF NF <; 0 3 x 61 «•’ 1 8 x- 20 9 x- 1 9 x 42 8 }> 0 0 5 p < 0 0 5 p > 0 0 5 p < 0 01 p > 0 0 5 p < 0 0 i NS NS NS Figure 4: Prevalence of residual roots by ethnic group and sex. Table I. Definitions used in this investigation Missing teeth. All permanent teeth not on the radiograph. Unerupted teeth. Teeth which had not reached the occlusal plane and which were not impeded from doing so. Impacted teeth. Teeth with fully or incompletely formed roots imped­ ed by hard tissue from reaching their correct relationship to the oc­ clusal plane and surrounding bone. HypercementosLs. Formation of excessive cementum on tooth roots. Periapical radiolucency. Radiolucency associated with the apex of a tooth root. Tooth fracture. Fracture of the crown and/or root of a tooth. Remaining roots. Roots which cannot be restored because of insuffi­ cient remaining healthy tooth tissue and/or supporting tissues. Focal radiopacity. A well circumscribed radiopacity in bone. Diffuse radiopacity. A radiopacity within the bone with poorly de­ fined margins. Unilocular radiolucency. A single radiolucency within bone not re­ lated to the apex of a tooth. Multilocular radiolucency. Multiple radiolucent areas within bone not related to tooth apices. Mixed radiolucency/radiopacity. Radiopacity within a radiolucency. Supernumerary tooth. An additional tooth present in a patient with a full complement of teeth. Compound ondontome. Ondontome which bears superficial ana­ tomical similarity to normal teeth. (Shafer, Hine and Levy 1983) Complex odontome. Odontome with an irregular mass of hard tis­ sue bearing no morphological similarity to even rudimentary teeth. (Shafer, Hine and Levy 1983). Mesiodens. A supernumerary tooth in the midline. Journal of the D. A S. A.—March 1988 ll3 M.B. Finkelstein, J.F. Lownie, P.E. Cleaton-Jones In general, the Caucasoid: Negroid and male: female pat­ terns of lesions seen in this study have been irregular; no con­ sistent pattern has emerged. The most striking difference seen was the high prevalence of residi al roots seen in Negroid fe­ males compared with the other subgroups. CONCLUSIONS The present investigation has shown that it is possible to diag­ nose a series of lesions on panoramic radiographs with high reproducibility. The panoramic radiograph is thus a useftil one for monitoring the prevalence of lesions that can be seen on such radiographs. It is suggested that screening of such le­ sions at intervals could be a useful aid to planning of hospital services. ACKNOWLEDGEMENTS The authors wish to thank Professor J.F. van Reenen the Dean/Director of the Oral and Dental Teaching Hospital of the Witwatersrand for making the radiographic material avail­ able; and to Miss A.K. Ruth for typing the manuscript. REFERENCES Allatar, M .M ., Baughman, R.A. & Collett, A.K. (1980). A survey of panoramic radiographs for evaluation of normal and pathological findings. Oral Surgery 50, 472-478. Barret, A.P., Waters, B E. & Griffiths, C.J. (1984). A critical evaluation of panoramic radiography as a screening method in dental practice. Oral Surgery, 57, 673-677. Christen, A.G., Meffert, R.M. Comyn, J. & Tiecke, R.W. (1969). Oral health of dentists. Analysis of panoramic radiographic survey. Journal o f the American Dental Association, 75, 1167-1168. Cuttino, C.L., Pogozelski, R.S., Richard, R.G. & Tiecke R.W. (1969). Panoramic radiographic sur­ vey of dentists, interpretation of findings. Journal o f the American Dental Association 79, 1179-1182. Farman, A.G., Joubert, J.J. de V. & Nortje, C.J. (1978). Focal osteosclerosis and apical periodon­ tal pathosis in “ European” and Cape Coloured dental outpatients. International Journal o f Oral Surgery 7, 549-557. International Dictionary o f Medicine and Biology (1986). Ed-in-chief Landau, S.I. pp 478, 1882 New York: John Wiley. Johnson, C.C. (1976). Analysis of panoramic survey. Journal o f the American Dental Association 81, 151-154. Langland, O.E., Langlais, R.P. Morris, C.R. & Preece, J.W. (1980). Panoramic radiographic survey of dentists participating in ADA health screening programes 1976, 1977 and 1978. Journal o f the American Dental Association 101, 279-282. Langland, O.E., Langlais, R.P., Morris, C.R. & Preece, J.W. (1982) Principles and Practice o f Pa­ noramic Radiography. p282 Philadelphia: Saunders. Meister, F., Simpson, J. & Davis, E.E. (1977). Oral health of airmen; analysis of panoramic radio­ graphs and polaroid photographic survey. Journal o f the American Dental Association, 94, 335-339. SAS Institute Inc. (1985). SAS Users Guide: Basics, version 5 ed ppl290. Cary N.C.: SAS Institute Inc. Updegrave, W.J. (1966). The role of panoramic radiography in diagnosis. Oral Surgery 22, 49-57. Shafer, W .G., Hine. M.K. & Levy B.M. (1983). A Textbook o f Oral Pathology, 4th ed. p308 Phila­ delphia: Saunders. White, S.C. & Weissman, D.D. (1977). Relative discernment of lesions by intraoral panoramic radio­ graphy. Journal o f the American Dental Association, 95, 1117-1121. World Medical Assembly. (1964). Declaration of Helsinki. World Medical Journal. 11, 281. Vaal Health Services Tandartse Aansoeke word gevra van Tandartse om aan te sluit by ’n nuut gestigde groepspraktyk hoofsaaklik, maar nie uitsluit- lik, vir Nie-blanke lede te Vanderbijlpark. Die praktyk funksioneer op ’n soortgelyke basis as sekere klinieke in die V.S.A. (Health Maintenance Organisations). Daar sal ’n ten voile ge-integreerde moderne Mediese Sen- trum met ondersteunende Mediese Dienste wees. Vanderbijlpark is ’n moderne stad gelee op die walle van die Vaalrivier met uitstekende skole, Technikon en ’n plaas- like Universiteit. Dit neem 40 minute op ’n dubbel snelweg na Johannesburg. ’n Aantreklike akademiese program word aangebied wat die bywoning van opknapingskursusse insluit. Die vergoeding wissel tussen R54 000 en R60 000 per jaar afhangende van ondervinding sowel as motorkar en ander byvoordele. Belangstellende tandartse word uitgenooi om telefonies of skriftelik navraag te rig aan: Die Afdelings Personeel Bestuurder Mnr D Smit Posbus 8 VANDERBIJLPARK 1900 Telefoon: (016) 33-0031 DENTIST — WELKOM Applications are invited from registered Den­ tists for appointment in a full-time capacity to provide services for members of the Mines Benefit Society and their dependants in mod- ernly equipped dental surgeries at Welkom. Remuneration package R66 000,00 to R78 000,00 per annum according to experi­ ence. 42 Days annual leave. Subsidised hous­ ing, medical benefit and group life insurance schemes, assistance with furniture removal and refresher courses. Written application stating age, qualifications, experience, marital status, degree of bi­ lingualism and telephone number should be addressed to: The General Manager, Mines Benefit Society, PO Box 23257 JOUBERT PARK 2044. Telephone: (011) 725-2540. Tydskrif van die T.V.S.A.—Maart 1988 114