Gender and race distribution of dental graduates (1985-2004) and first year dental students (2000-2005) in South Africa.

This paper, written at the close of a decade of democracy in South Africa, sets out to analyse the demographic profile of dental graduates from 1985-2004 at the five Faculties/Schools of Dentistry in South Africa. A comparison of the profiles for the pre-democracy (1985-1994) and post-apartheid (1995-2004) periods has been made. The demographic profile of first year dental students from 2000-2005 is also presented. From 1985-1994, most dental graduates were male (79%), but this changed substantially from 1995-2004, with females comprising 46% of those graduating. In the pre-democracy period, more than three-quarters of all graduates were White (78%), decreasing to 46% in the post-apartheid period under review. Black graduates increased from 6% to 24% across the two study periods. Amongst the first year dental student intake from 2000-2005, females comprised 57%. There was an almost equal distribution across the White, Black and Asian groups. Dental faculties/schools have made important strides in transforming the demographic profile of their students. The percentage of Black graduates, however, needs to be significantly increased if it is to reflect the national population. Faculties/schools must further ensure that able students from working class background are identified and considered for acceptance into the undergraduate dental programme, and should then be offered the necessary academic and mentoring support to enable success.

The new Pretoria curriculum.

Macro-environmental changes in tertiary education have prompted a review of dental curricula in order to address shortcomings in the traditional curriculum. This paper defines the philosophical principles that highlight concepts in the new innovative curriculum. The stance adopted in the development of the macro- as well as the micro-curriculum is described.

The prevalence of oral pathoses in a private dental practice: a 30 month survey.

The purpose of this study was to determine the prevalence of oral lesions in a private dental practice, which treats a broad spectrum of patients from both urban and rural areas. All oral lesions were documented over a 30 month period in a research programme, which formed part of the normal patient treatment plan. The lesions were analysed according to the prevalence of the lesions, race, age and gender distribution, and the ratio of lesions diagnosed by the practitioner compared with those presented for treatment by the patients. A total of 8418 patients were examined and 151 pathological lesions were diagnosed, representing 46 different conditions. The commonest conditions were fluorosis (11 per cent of lesions) and geographic tongue (11 per cent of lesions seen). Twenty conditions (47.8 per cent) were seen only once. The male:female ratio was 1.17:1. A total of 74 per cent of the lesions were seen in patients between the 2nd and the 5th decades and 25 per cent in the 4th decade. Patients seeking treatment suffered from conditions such as fluorosis causing aesthetic problems. On the other hand premalignant lesions such as leukoplakia and life threatening diseases were usually detected by the dentist, which stresses the importance of a thorough clinical examination of all patients. Fluorosis documented in 17 patients in this study, led to analysis of drinking water in the Dennilton area, which was found to contain toxic levels of fluoride.

Working patterns of male and female dentists in South Africa.

Studies in England, USA and Australia, have shown that the working hours of female dentists do not differ significantly from the working hours of their male counterparts, until they have children. The purpose of this study was to establish whether the same phenomenon exists in South Africa and to compare working patterns of South African male and female dentists regarding nature of practice/employment, location of practice, work satisfaction and breadwinner status. Questionnaires were sent to 285 female dentists, selected by their first name in the SAMDC register. An equal number of questionnaires were sent to male dentists, selected according to the proportional random sampling technique. The total response achieved was 35.8 per cent. The female dentists' working hours showed a distinct drop as soon as they started a family (from 86 per cent, practising more than 35 hours per week, to 34 per cent) while the male dentists' hours remained unchanged (90 per cent). The fact that so many more male dentists (81 per cent) than female dentists (19.6 per cent) are primary breadwinners, explains why such a high percentage of female dentists can afford to work part-time. The majority of both male (89.7 per cent) and female (70 per cent) dentists are in private practice. However, a considerably larger percentage of females work for a salary in State clinics and at Universities. This study shows that gender, breadwinner status and the presence and age of children have a marked influence on the working patterns of South African dentists.

Allergies to dental materials.

Allergies related to dentistry generally constitute delayed hypersensitive reactions to specific dental materials. Although true allergic hypersensitivity to dental materials is rare, certain products have definite allergenic properties. Extensive reports in the literature substantiate that certain materials cause allergies in patients, who exhibit mucosal and skin symptoms. Currently, however, neither substantial data nor clinical experience unequivocally contraindicate the discontinuance of any of the materials, which include dental amalgam and nickel- and chromium-containing metals. The dentist forms a vital link in the team approach to the differential diagnosis of allergenic biomaterials that elicit symptoms in a patient, not only intraorally, but also on unrelated parts of the body.

In vivo effects of urease-producing bacteria involved with the pathogenesis of infection-induced urolithiasis on renal urokinase and sialidase activity.

Many hypotheses have been proposed for renal stone formation. It has been argued that with infection-induced renal stones the hydrolysis of urea by bacterial urease increases urinary pH, with consequent stone formation. Unfortunately, this theory is not applicable to the micro-organisms that do not produce urease (e.g. Escherichia coli). It has been recently reported that E. coli reduces the urinary urokinase activity of male rats, but does not influence the urinary sialidase activity. This study has now been expanded to the urease-producing bacteria Proteus mirabilis, Staphylococcus aureus, S. epidermidis, Pseudomonas aeruginosa and Micrococcus luteus. Subcutaneous injections with these bacteria were found to significantly (P < 0.003) reduce the UK activity of extrarenally obstructed kidneys. The urease-producing mammalian skin bacterium, M. luteus, was, however, the exception (P = 0.1079). In contrast to S. epidermidis, P. aeruginosa and M. luteus (P < 0.0213), P. mirabilis and S. aureus had no effect on renal sialidase activity (P < 0.4047). These results may explain why Proteus species are predominant in infection-induced renal stones. According to the urokinase-sialidase hypothesis, a decrease in urinary urokinase activity should increase the uromucoid levels, whilst no effect on the urinary sialidase activity should favour conversion of urinary uromucoid to mineralizable matrix. These conditions may lead to renal stone formation. An increase in urinary pH resulting from urease-producing micro-organisms will increase salt precipitation on the uromucoid. It is thus concluded that urease-producing bacteria may play a double role in renal stone formation.

Comparative review of bitemark cases from Pretoria, South Africa.

Bitemark evidence has become more scientifically based and is currently widely accepted in the legal process. Bitemarks can be inflicted by humans or animals on humans, animals and a variety of inanimate objects and can be found on any part of the body, with their quality and appearance being influenced by a variety of factors. The purpose of this study was to record the experiences with bitemark cases presented to forensic odontologists at the University of Pretoria from 1983-1993 and to compare them with trends and findings elsewhere. Sixteen cases are presented, of which 14 were bitemarks inflicted by humans and two by dogs. Thirteen cases occurred in human tissues, three in inanimate objects. Of the bitemarks in human skin, most were present on the arms, followed by the face, thorax and back. Bitemarks over the entire body were seen in the two victims bitten by dogs. The male:female ratio was 4:1 and in 46% of cases single marks were present while the rest were multiple. Eight of the victims had been assaulted. Two cases were associated with sexual behaviour (rape), two were inflicted by dogs, and the circumstances surrounding one case were unknown. A variety of factors complicated the investigations. The major factors responsible for disqualifying bitemarks as evidence included mutilation, removal of tissues, inexperience of officials involved and multiple bitemarks. The results of the study confirm the importance of bitemarks as forensic evidence. Humans are the primary victims with the arm being the anatomical site most often involved. Inexperience on the part of the investigating officers and other officials in the handling of these cases strongly emphasises the need for proper training and education of these personnel.

The Helderberg air disaster--forensic odontological investigations.

A Boeing 747-224B Combi of the South African Airways, the "Helderberg", crashed into the sea near Mauritius on 28 November 1987. All 159 people on board died and dental tissues were present in only eight of the 15 lots of human remains recovered. Ante-mortem dental records were collected by a team in Johannesburg while the post-mortem examinations were conducted in Mauritius. The special circumstances surrounding an accident at sea resulted in the low number of bodies available for identification procedures. Of the eight remains which included dental tissues, five were identified by means of simple dental restorations, advanced dentistry, anatomical features of teeth and stages of development of teeth. One of the victims was identified by a process of exclusion and radiographic evidence played a decisive role in the identification process. (J Forensic Odontostomatol 1994; 12: 15-18) The variety of record-keeping styles and abbreviations used in different countries posed a major problem during the process and it is concluded that international standardization in record-keeping requires urgent attention.

Pyelonephritis: renal urokinase and sialidase (neuraminidase) activity in rats fed a standard laboratory diet.

Renal stone formation can be caused by many different and varied disturbances, some of which are poorly understood. The relationship between urinary infection and renal stone formation has not been completely clarified. It is argued that renal stones form primarily as a consequence of the hydrolysis of urea by the bacterial enzyme urease. However, no explanation is given for microorganisms that produce urease only occasionally or not at all. The question arises as to whether the infection-induced microorganisms might not be playing a double role in renal stone formation by not only producing urease, but also by affecting in vivo urokinase (UK) and sialidase (SA) activity. With this in mind, the effect of Escherichia coli on renal UK and SA activity has been studied in male rats with a normal diet. The renal UK (P = 0.208) and SA (P = 0.2135) activities did not differ significantly between the two kidneys of the same rat. In contrast, when drainage from one kidney of a rat was externally obstructed, the UK and SA activities differed significantly between kidneys (P < 0.015). An increase in UK (r = 0.6456, P < 0.0001) and SA (r = 0.7507, P < 0.0001) activity was observed over time in the obstructed kidney. Subcutaneous injections with E coli reduced the UK activity of the obstructed kidney significantly (p = 0.017). However, the SA activity remained the same (P = 0.3929).(ABSTRACT TRUNCATED AT 250 WORDS)

The fluoride content of enamel as a diagnostic aid in fluorosis.

This study was undertaken to compare the fluoride content ([F]) of sound and hypoplastic enamel of dogs' teeth for use as a diagnostic aid for fluorosis. Enamel biopsies (0.5N HClO4; 15 seconds; 3.143 mm2) were conducted on macroscopically sound areas of the middle buccal surfaces of the right upper canine teeth. The [F], and the calcium concentrations of the etching solutions were determined using the potentiometric analytical method and the flame spectrophotometer respectively. Depth of etch (DOE) was calculated. The results of the study showed that the higher [F] in the hypoplastic enamel when compared to that of sound enamel (p > 0.05), was more a result than a cause of the hypoplasia. In this study, the [F] of the enamel was used successfully to exclude the possibility of fluorosis.

The histological nature of epulides in dogs.

The histological characteristics of a series of 154 oral tumours with the clinical appearance of epulides in 129 dogs were reviewed. Diagnoses were based on current criteria in human oral pathology and compared with the original diagnoses. The histological findings suggested that the majority of epulides in the dog can be classified as focal fibrous hyperplasia (43.5 per cent), peripheral ameloblastoma (17.5 per cent), peripheral odontogenic fibroma (WHO type) (16.9 per cent) and pyogenic granuloma (1.95 per cent). In addition, a number of other odontogenic tumours (1.95 per cent) and non-odontogenic tumours (18.2 per cent) such as fibrosarcoma and squamous cell carcinoma, which are not traditionally associated with the clinical appearance of an epulis, were diagnosed. Of 74 lesions that were previously diagnosed as fibromatous and ossifying epulides, 50 (68 per cent) were reclassified as focal fibrous hyperplasia and 21 (28 per cent) as peripheral odontogenic fibroma (WHO type). The majority of lesions (76 per cent), which were originally classified as acanthomatous epulis, were found to be peripheral ameloblastoma. In addition, three squamous cell carcinomas, two rare odontogenic tumours and two cases of focal fibrous hyperplasia were diagnosed in this classification. It was concluded that, as in man, the term epulis is a clinically descriptive term and that the renal nature of these lesions should be determined histologically.

Diffuse peripheral odontogenic fibroma: report of 3 cases.

Since peripheral odontogenic fibroma (POF) is characteristically described as a solitary lesion and no diffuse POF had been reported in the literature, our cases should be considered as extremely unusual. Three diffuse cases of POF are described of which one case was seen in association with ocular and skin lesions. The question arises whether POF should be considered as a true odontogenic tumor rather than a diffuse hamartomatous lesion caused by uncontrolled induction of the gingiva. It is also possible that such lesions could be part of a yet undescribed syndrome.

Primary intra-osseous carcinoma of the maxilla in a horse.

An 8-year-old Hannoverian horse developed a swelling of the maxilla caused by a tumour of the hard palate. On histological examination the tumour was diagnosed as a primary intra-osseous carcinoma of the maxilla, a rare odontogenic tumour not previously described in the horse.

Tuberous sclerosis: report of a case with fibromatosis of the facial soft tissues.

Tuberous Sclerosis (TS) is a dominantly inherited disorder which is characterised by a triad of mental deficiency, epilepsy and angiofibromas of the face. Sub- and periungual fibromas, shagreen patches usually found in the lumbosacral region and hypopigmented skin lesions are less often seen. Paraventricular calcifications, skeletal disorders and rarely, ophthalmic tumours are also described. Oral manifestations include whitish confluent nodules on the mucosa, enamel hypoplasia, mandibular cysts, and oral fibromas. A case of fibromatosis of the subcutaneous tissue overlying the angle of the mandible is described together with TS. To the best knowledge of the authors, this is the first such case reported in the literature.

Diagnosis of oral precancer and cancer.

The early diagnosis of oral cancer and precancer is important because oral cancer is usually well advanced at the time of diagnosis, having spread to regional lymph nodes in a substantial percentage of cases. The earlier the diagnosis is made, the better the prognosis. Several diagnostic methods that are used, such as stomatoscopy, toluidine blue staining, oral exfoliative cytology, histopathological examination and other more advanced diagnostic procedures, are discussed.

Silica granuloma of a lymph node.

A case of silica granuloma in the submasseteric lymph node is presented. Sarcoidosis was excluded, as crystalline particles, with a double-refractile property, were seen in polarized light. The most probable cause was a delayed hypersensitivity reaction to silica from a lipstick cream introduced through a recurring angular cheilitis.

Histological changes in the penis of the Chacma baboon--a model to study aging penile vascular impotence.

Light and scanning electron microscopy was performed on the penes of Chacma baboons to establish their suitability as animal model for studying vascular impotence. Analogous aging penile vascular changes were found in man, and a fibrous trabeculopathy with intertrabecular senechiae was demonstrated. Considering the corresponding changes, the Chacma baboon could thus be regarded suitable for studying the pathophysiology of aging penile vascular changes.