Comparative Immunohistochemical Analysis of p53 and Alpha-SMA in Ameloblastoma, AOT and OKC.

OBJECTIVES: Ameloblastoma is a benign but highly infiltrative tumour, a behaviour that is lacking in adenomatoid odontogenic tumour but partly shared by the odontogenic keratocyst which possesses a unique intrinsic growth potential with marked ability for destroying bone and a high tendency recurrence. High frequency of stromal myofibroblasts (assessed with alpha smooth muscle actin (α-SMA) correlates with aggressive behaviour while p53-cell cycle regulation system is critical in odontogenic tumours with immunoreactivity signifying prognostic status. This study aims to determine and compare the immunoreactivity of these selected tumours to p53 and α-SMA in order to establish if a relationship exists between the frequency and pattern of distribution of myofibroblasts and the behaviour of these lesions. MATERIALS AND METHODS: 69 blocks of ameloblastoma, and 23 each of adenomatoid odontogenic tumor (AOT), and odontogenic keratocyst (OKC/KCOT) were retrieved. Immunohistochemistry technique was applied for evaluation of these two markers staining with primary antibodies to p53 and -SMA and the frequency and pattern of distribution of myofibroblasts and immunoreactivity to p53 analysed and compared using ANOVA. p was set at <0.05. RESULTS AND CONCLUSION: Immunoreactivity to p53 and α-SMA was highest in ameloblastoma (solid compared to unicystic) with highest mean positive cells to α-SMA (29.7±20.1) and p53 (28.3±24.5) in plexiform ameloblastoma. This suggests that ameloblastoma was the most aggressive of tumours studied. Different pharmacological agents that can regulate stromal MF are useful aids to decrease the need for radical surgery in extensive and aggressive odontogenic tumours.

ABSTRAIT OBJECTIFS: L'améloblastome est bénin mais untumeur mes infiltratif, un comportement qui fait défaut dans la tumeur odontogénique adénomatoïde mais en partie partagé par le kératocyste odontogène qui possède un potentiel de croissance intrinsèque unique avec une capacité marquée de destructionet une récidive à forte tendance. Haute fréquence de stromalmyofibroblastes (évalués avec de l'actine musculaire alpha lisse (α-SMA) est en corrélation avec un comportement agressif lors de la régulation du cycle des cellules p53 est essentiel dans les tumeurs odontogènes immunoréactives signifiant le statut pronostique. Cette étude vise à déterminer et comparer activité l'immunoré de ces tumeurs sélectionnées à p53 et α-SMA afin d'établir s'il existe une relation entre le fréquence et schéma de distribution des myofibroblastes et de la comportement de ces lésions. MATÉRIAUX ET MÉTHODES: 69 blocs d'améloblastome, et 23 chacun de tumeur odontogénique adénomatoïde (AOT) et odontogènedes kératocystes (OKC/KCOT) ont été récupérés. Immunohistochimiela technique a été appliquée pour l'évaluation de ces deux marqueurs de coloration avec des anticorps primaires dirigés contre p53 et α-SMA et la fréquence et schéma de distribution des myofibroblastes et de l'immunoréactivité àp53 analysé et comparé à l'aide de l'ANOVA. p a été fixé à <0,05. RÉSULTATS ET CONCLUSION: Immuno réactivité à p53 et α-SMA était la plus élevée dans l'améloblastome (solide par rapport α-SMA (29,7±20,1) et p53(28,3±24,5) dans l'améloblastome plexiforme. Cela suggère que L'améloblastome était la tumeur la plus agressive étudiée. Les agents pharmacologiques différentes peuvent réguler la MF stromale sont des aides utiles pour diminuer le besoin de chirurgie radicale en cas de chirurgie étendue et agressive tumeurs odontogènes. Mots-clés: Améloblastome, AOT, OKC/KCOT, p53, α-SMA, myofibroblastes, tumeurs odontogènes, immunoréactivité.

Bacteriologic features and antimicrobial resistance of organisms associated with extracted teeth: findings from a Nigerian university teaching hospital.

BACKGROUND: Empirically prescribed antibiotics are widely employed in the management of odontogenic infections. OBJECTIVE: To characterise the infections associated with extracted teeth and assess effectiveness of the antibiotics prescribed empirically following tooth extraction. METHODS: The study was cross-sectional and consisted of 41 consecutively recruited subjects who required extraction for infections associated with the tooth. Appropriate clinical specimens were collected aseptically from each patient and transported in Stuart's transport medium for processing in the laboratory. Isolation, identification, and susceptibility pattern of anaerobic and facultative organisms were done employing standard bacteriologic techniques. Antimicrobial susceptibility testing was performed by the disc diffusion technique. RESULTS: There were positive cultures for 37 patients. Twenty-eight aerobic (45.9%) bacteria and 32 anaerobic (54.1%) bacteria were isolated, an approximation of two microorganisms per patient. Staphylococcus was the most predominant aerobe (25.0%) whereas Bacteroides fragilis was the most predominant anaerobe (34.2%). All the bacteria isolated showed in vitro resistance to cephalexin, cloxacillin and metronidazole. Eighteen (64.3%) different aerobic bacteria and 13 (40.6%) different anaerobic bacteria were sensitive to ciprofloxacillin and these included staphylococcus and Bacteroides fragilis. Sensitivity pattern for amoxycillin was very poor with 3.6% and 6.3% for aerobes and anaerobes respectively. CONCLUSION: Odontogenic infections from our centre are polymicrobial in nature with anaerobes predominating. High resistance to most of the antibiotics routinely prescribed in our centre is common. Ciprofloxacillin demonstrated the highest sensitivity pattern.

Acceptance of hepatitis B vaccine by workers in a Nigerian teaching hospital.

OBJECTIVES: To determine the pattern of vaccine uptake by hospital personnel in a specifically designed pioneer hepatitis B vaccination programme and to highlight major lessons for ensuring success in future programmes. DESIGN: A review of vaccination and employment records for a forty four-month period and comparative analysis on the basis of professional grouping and work units. SETTING: Obafemi Awolowo University Teaching Hospital Complex, Ile-Ife, Nigeria. SUBJECTS: A total of 2,548 employees of the teaching hospital that have worked for a minimum of one year on a continuous basis between April 1992 and December 1995. INTERVENTIONS: Procurement of recombinant hepatitis B vaccine (Engerix, SmithKline Beecham) by the hospital management and provision of the same to all interested employees of the teaching hospital at no cost under a vaccination programme which was conducted on an on-site basis. MAIN OUTCOME MEASURES: 'Participation' in the vaccination programme was defined as the uptake of at least one dose of hepatitis B vaccine, and 'compliance' defined as the receipt of the three prescribed doses of the hepatitis B vaccine. RESULTS: The level of participation in the vaccination programme was high with 91.9% of the target population of hospital workers receiving at least a dose of the vaccine, while only about half (53.8%) of the group complied with receiving the required three doses of the vaccine. In terms of participation, by professional grouping, laboratory workers and nurses recorded the lowest rates (82.5% and 84% respectively), while 100% participation was recorded in respect of the staff of engineering, medical records, pharmacy and physiotherapy departments. The highest rate of compliance (receipt of three doses) was also found among non-clinical workers (medical record personnel--76.3% and engineering staff--69.5%) while the lowest rate was found among nurses (39.7%) and doctors (40.3%). CONCLUSION: Workers with the highest possibility of knowledge of, and exposure to hepatitis B infection within the hospital setting--doctors, nurses, and laboratory workers--showed the greatest apathy to the vaccination programme. Reasons for this trend demand close examination, and subsequently, identification of specific action that needs to be taken to improve the uptake of the vaccine by the target population, particularly the high-risk groups, in future programmes. Among others, targeting all groups of workers with appropriate education on the infection; active involvement of professional groups in the planning and execution of the vaccination programme; and review of the implementation logistics are some of the key points to note for future programmes.

Hepatitis D virus antigen in HBsAg positive chronic liver disease in Nigeria.

Hepatitis B virus (HBV) is strongly associated with an aggressive type of chronic active liver disease (CALD) and hepatocellular carcinoma, which tend to present in the relatively young, in sub-Saharan Africa. It is known that co-existent infection with HDV tends to aggravate the course of HBV-associated liver disease. This study was carried out to determine the sero-prevalence of hepatitis D virus (HDV) among thirty one consecutive southwestern Nigerians with HBsAg-positive, HCV antibody-negative chronic liver disease. Alongside, we tested for HBsAg and the HDV antigen in fifty randomly selected sera each from blood donors and university freshmen undergoing pre-admission medical tests and who had no clinical evidence of liver disease. The HDV antigen (HDVAg) was found in the sera of two of 31 (6.5%) patients. Among the blood donors and university freshmen, HBsAg prevalence was twelve and eight per cent respectively, while HDVAg was present in none. In addition, liver biopsies of 28 other patients were stained for HDVAg. None of these was positive. These findings show that HDV prevalence is low in our community, and suggest that the virus might play only a minor role in the pathogenesis of HBsAg-associated chronic liver disease among our patients. A review of reports on the epidemiology of HDV in sub-Saharan Africa shows a rather complicated pattern that makes its impact on HBsAg-associated CALD difficult to assess. More studies designed to elucidate this pattern of HDV epidemiology are called for.

Craniocervical necrotizing fasciitis in Ile-Ife, Nigeria.

Sixteen cases of necrotizing fasciitis were seen at the Obafemi Awolowo University Teaching Hospital, Ile-Ife, Nigeria from 1990 to 2000. Primary craniocervical involvement was recorded in seven patients (five men and two women). The clinical records of five patients were sufficiently detailed to allow us to report their age, aetiology, predisposing illness, clinical features, complications, management regimen and outcome. The patients were aged 30-75 years and in four of them odontogenic infections were the cause of the condition. Hypertension, diabetes mellitus and obesity were the underlying systemic diseases in three cases and the body/angle region of the mandible was the predominant site of the infection on the face. All five cases had involvement of the neck. Mediastinal extension was recorded in three cases. Two patients had complications: one had septicaemia and renal failure and the other developed bone necrosis. Pre-existing ill health, old age, late surgical intervention, and mediastinal and thoracic extension of infection were responsible for the only death. Treatment involved frequent and multiple surgical debridement, aggressive antimicrobial treatment and control of systemic disease. Early recognition, prompt surgical intervention, and aggressive antimicrobial treatment are essential to minimize morbidity and mortality. Rapid progression of infection, financial constraints, delayed referrals from rural clinics and distance to the tertiary hospital caused problems.

Maxillary haemangiopericytoma: a case report.

BACKGROUND: Haemangiopericytoma is a very rare slow-growing vascular tumour with a variable malignant potential, constituting less than 1% of all neoplasms. It may arise from any blood vessel and in any organ of the body. Primary haemangiopericytoma of bone is even rarer, constituting about 0.1% of bone tumours. The tumour is extremely rare in Africans and particularly in the head and neck region. STUDY DESIGN: We describe the case of a 66-year old Nigerian with haemangiopericytoma of the maxilla, who presented with a recurrent but painless jaw mass. RESULTS: Surgical resection of this tumour is potentially bedevilled with the risk of torrential haemorrhage and high rate of recurrence. This risk may be substantially reduced by wide surgical resection with a careful microscopical examination of the resection margins and the institution of adjuvant radiotherapy in incompletely resected tumours. Chemotherapy has no known role in the management of haemangiopericytoma. Postoperative radiation therapy appears to be effective against tumour recurrence. CONCLUSION: Even then, long-term follow-up is essential in all cases. To our knowledge, this is the first report of this entity in an African.

Giant frontal sinus mucocoele with intracranial extension and orbital displacement in an elderly Nigerian.

Mucocoele of the frontal sinus presents with initial sign of forehead swelling in about 10% of cases, and cases with huge intracranial extension have been reported to be rare. We present a case of a giant frontal sinus mucocoele with intra-cranial and intra-orbital extensions exerting a mass effect on the anterior cranial fossa in a 78 year old Nigerian female with resultant forehead swelling, proptosis and total blindness of the left eye. Diagnosis was made on clinical and radiological basis, and enucleation using coronal flap approach was done. Immediate repair of the resultant frontal bone defect was effected through the use of a curved 0.5mm stainless steel wire fixed in 3 layers across the defective frontal bone over which the soft tissues of the forehead were undermined for primary closure on sound bone. This approach was considered more appropriate than a split rib graft in view of the patient's age. No evidence of recurrence was recorded during a one-year post-surgery follow-up, suggesting that mucocoele, regardless of size can be treated with conservative surgical approach provided all cystic lining and mucocoele are removed.

Pattern of head and neck malignant tumours in a Nigerian teaching hospital--a ten year review.

BACKGROUND: In Nigeria record of incidence and pattern of Head and Neck malignancies is scanty. In our Hospital, there had been no prior published report on this subject. OBJECTIVE: To study the pattern of occurrence of Head and Neck malignancies treated in Obafemi Awolowo university Hospitals Complex, Ile Ife, Nigeria. METHODS: medical records of patients with histopathologically confirmed head and neck malignancies over a 10 year period (1989--1998) were analyzed. MAIN RESULTS: Three hundred and thirteen (313) cases, made up of 184 (59%) males and 129 (41%) females were found. The most common sites for head and neck malignancies were found to be in the oral cavity (36.8%), the neck (26.8 %), the thyroid (13.7 %), and the esophagus (5.1%). The paranasal sinuses and the ear were the least affected anatomical sites with one (0.3 %) of cases each. The histopathological tumour types found in this work were lymphoma (40.26%), squamous cell carcinoma (25.23%), sarcoma (2.6%), while many other minor histopathological variants accounted for 31.9%. Lymphoma was the most common in children, while carcinoma was found in, and forms the most common histopathological variant of head and neck malignancies in the older age group. PRINCIPAL CONCLUSIONS: There is a high incidence of childhood head and neck malignancies found in this study in contrast to the Western literature where the highest incidence is found in the older age group and the elderly. Jaw malignancies constituted the most common malignancies of the oral cavity. Lymphoma and thyroid malignancies are relatively common in our center.

Dental radiographic features of impacted third molars and some management implications.

The objective of the study was to determine the principal dental radiographic features of impacted third molars and to highlight some management implications, 255 periapical radiographs belonging to 197 patients with the clinical records were examined. The age of the subjects, sex, and degree of impaction, inclination, depth, mesiodistal space and associated pathology were documented as well as the number of roots and their relationship to the neurovascular bundle. The mean age was 23.4 years with more female teeth (152, 59.6%) than male (103, 40.4%). Majority were partially erupted (223, 91.4%) with vertical impaction most commonly seen in 80 teeth (31.4%). Over half of the teeth (135, 52.9%) had no obvious relationship with the inferior alveolar neuro-vascular bundle and where this existed, darkening of the root was the most common radiographic indicator (55 teeth, 21.6%). Most of the teeth (54.9%) had no obvious pathologic changes associated. In those with pathologic changes, periodontal bone loss and a wide follicle were most commonly observed (44 teeth or 17.3% in both cases). Older subjects had significantly more periodontal bone loss (p = 0.001). Periapical radiographic examination can reveal vital information for treatment planning of impacted teeth and the monitoring of asymptomatic teeth.

Management of impacted third molars among Nigerian dentists.

Seventy-five Nigerian dentists were interviewed on their approach to the management of impacted third molars. The mean age of the dentists was 34.8 years, with a male/female ratio of 3.4:1. Most of the female dentists were found in the training institutions (p = 0.005). More than half of the dentists (58.7%) practiced in institutions with dental schools (training institutions), majority preferred the buccal approach (92%), and all the dentists (100%) preferred third molar disimpaction under local analgesia. Most dentists (88%) prescribe antibiotics following third molar surgery. Fifty dentists (66.7%) routinely reviewed all patients postoperatively while 12 dentists (16%) were of the opinion that all impacted third molars should be extracted. Only 21 dentists (28%) were aware of any protocol on the management of impacted teeth. More dentists in the training institutions performed third molar surgery less frequently than dentists in other hospitals (p = 0.07) who tend to employ chisels/mallet for bone removal (p = 0.0004). The need for continuing education and the formulation of guidelines in order to assist dentists to make informed decisions is emphasised. This will help conserve scarce resources and enhance the operation of the newly introduced National Health Insurance Scheme.

The validity of ultrasonography in the diagnosis of zygomaticomaxillary complex fractures.

The aims of this study were to determine the sensitivity, specificity, positive and negative predictive values of ultrasonography in detecting zygomaticomaxillary complex fractures, and to highlight factors that may affect the validity of ultrasonography in the diagnosis of zygomaticomaxillary complex fracture. Twenty-one patients with suspected fractures of the zygomaticomaxillary complex presenting at the authors' hospital were included in this prospective study. All the patients had plain radiographic and computed tomography (CT) investigations. All underwent ultrasonographic examination of the affected region using an ultrasound machine with a 7.5 MHz probe. The different radiologists were not aware of the results of the other two investigations. Statistical significance was inferred at P<0.05. The validity of ultrasonography varied with fracture sites with a sensitivity of 100% for zygomatic arch fractures, 90% for infraorbital margin fractures and 25% for frontozygomatic suture separation. Specificity was 100% for the three types of fracture. There was no statistically significant difference in the ability of CT scan and ultrasonography to diagnose fractures from various zygomaticomaxillary complex fracture sites (P=0.47). Ultrasonography has proved to be a valid tool for the diagnosis of zygomatic arch and displaced infraorbital margin fractures.

Clinico-epidemiological analysis of orofacial rhabdomyosarcoma in a Nigerian population.

Rhabdomyosarcoma (RMS) is a malignant soft tissue neoplasm, with varying degrees of striated muscle cell differentiation and a relative predilection for the head and neck region. The objectives of this study were to determine the clinical and histological patterns of RMS, to assess the sociodemographic profile of reported RMS cases, and to highlight the management challenges and outcomes of these cases in a country lacking resources such as Nigeria. Patients diagnosed with RMS, based on clinical and histological evaluation, and recorded in the cancer registry of two maxillofacial centres in Nigeria were reviewed. 21 patients met the inclusion criteria for this study. Their ages ranged from 24 days to 42 years. In all of them multiple anatomical sites were involved. The primary site of the lesion could not be determined. Embryonal and alveolar subtypes were mainly found in the maxilla. There was no statistically significant association between the site of the lesion and the histological type (p=0.39). The patients' age was statistically significantly associated with the histological type (p=0.008). Most patients reported at an advanced stage, contributing to the poor prognosis and management outcome of cases evaluated.

A clinical evaluation of dry socket in a Nigerian teaching hospital.

PURPOSE: We sought to determine the incidence of dry socket in a Nigerian teaching hospital and to evaluate the patients' demographic pattern, predisposing factors, the treatment given, and treatment outcome. PATIENTS AND METHODS: A retrospective review of records of dental extractions complicated by dry socket in Obafemi Awolowo University Teaching Hospital, Ile-Ife, between January 1996 and December 2000 was undertaken. Information retrieved included patient sociodemographic data, indications for extraction, tooth extracted, status of attending surgeon, onset of symptoms, relevant findings of the examining clinician, interval before presentation, treatment given, and its outcome. RESULTS: Of the 3,319 dental extractions performed in 3,008 patients, 136 (4.1%) were complicated by dry socket. The patients' mean age was 33.4 (15.4) years and a peak age incidence of 21 to 30 years was found. A slight female preponderance (1.4:1) was observed. The majority of patients were in the low-income group, and presentation in the hospital was prompt in the high-income group. Mandibular teeth were affected 3 times more than maxillary teeth (P =.00080). Most cases of dry socket resulted from extractions performed by undergraduates and house officers. Various underlying systemic conditions were found in 11.0% of cases, none of which included use of oral contraceptives. Treatment was usually the use of zinc oxide eugenol dressing in an irrigated socket, combined with antibiotic therapy in 45.3% of cases. No adverse reaction to zinc oxide eugenol was observed. CONCLUSION: The incidence of dry socket in our hospital is 4.1%. The mandible was involved 3 times more than the maxilla. With the use of zinc oxide eugenol dressing, 70.6% of patients completed treatment satisfactorily and 29.2% were lost to follow-up.

Familial Burkitt's lymphoma in Nigerians.

Three Nigerian sib-pairs with familial Burkitt's lymphoma (BL) seen between 1986 and 1996 are described. Their ages ranged from 4 to 20 years (median 9.5), and there were five males and one female. The mean age interval between each pair at presentation was 4 years (3-6) and the mean time interval 22 months (0.3-41). Two of the sib-pairs were sex-concordant, including a set of monozygotic twins. Five of the patients presented in stage C and one in stage A. Parental consanguinity was not found in any group. Space-clustering was confirmed in all three but time-clustering in only one. The occurrence of BL in multiple members of the same family, the presence of sex concordance and the relatively wide variation in the time of onset of disease between each pair suggest genetic predisposition as a possible additional aetiological factor for BL in the families affected.