Strategies for Oral Health Research in Africa and the Middle Eastern Region.

The highest burden of diseases worldwide is in low- and middle-income countries, but due to lack of capacity and inadequate infrastructure, research output from these countries is unable to address existing and emerging challenges in health care. Oral health research has particularly been hampered by low prioritization, resulting in insufficient development of this sector. There is an urgent need for research correlating oral health to upstream social and environmental determinants and promoting the common risk factor approach for prevention of noncommunicable diseases. Population-wide preventive measures for oral health care are more effective than purely curative approaches, especially for vulnerable groups who have limited access to information and appropriate health care. This article identifies priorities and proposes strategies for researchers, stakeholders, and policy makers for the initiation and sustenance of appropriate oral health care research. The proposed interventions are intended to promote collaboration, capacity building, and health advocacy. Local ownership in multinational research projects in low- and middle-income countries, complemented by skills transfer from high-income countries, is encouraged to ensure that regional health needs are addressed. Emphasis is placed on a shift toward translational research that has a direct impact on oral health care systems.

The pattern and occurrence of ameloblastoma in adolescents treated at a university teaching hospital, in Kenya: a 13-year study.

UNLABELLED: Ameloblastoma presenting in the adolescent age group is rare with few studies documenting their occurrence. AIM: The aim of this study was to carry out an analysis of the pattern and occurrence of ameloblastoma in those less than 20 years of age. MATERIALS AND METHOD: Patients from the University of Nairobi Dental teaching Hospital treated for ameloblastoma were included in the study over a 13-year period. The study highlights the demographic, clinic-radiographic and histologic features of benign locally aggressive lesions. RESULTS: A total of 127 patients were recorded of which, 27 (21.3%) were below the age of 20 years; no case was reported below the age of 10 years. 18.5% were below the age of 14 years and 81.5% were 15-19 years old. The gender predilection was ∼1:1. All of the tumours occurred in the mandible, with radiographic features of a multilocular radiolucencies (85.2%); and a fewer unilocular lesions (14.8%). The management is in a staged-wise approach: resection and/or disarticulation with temporary reconstruction using mandibular stainless steel or titanium plates and delayed bone grafting. CONCLUSION: The occurrence of ameloblastoma can mimic an odontogenic cyst, clinicians therefore need to be vigilant when examining adolescents so that conservative treatment is started early in order to reduce the subsequent morbidity.

AETIOLOGY, PATTERN AND MANAGEMENT OF ORAL AND MAXILLOFACIAL INJURIES AT MULAGO NATIONAL REFERRAL HOSPITAL.

OBJECTIVE: To establish the aetiology, pattern and methods of management of oral and Maxillofacial injuries (OMFIs) seen at the Oral and Jaw injuries unit of Mulago National Referral Hospital (MNRH) Kampala, Uganda, over a ten year period. DESIGN: A descriptive retrospective study. SETTING: Oral and jaw injury unit of Mulago National Referral Hospital, Kampala, Uganda. RESULTS: One thousand two hundred and three patient records met the inclusion. criteria. The age range was 1-90 years with a male: female ratio of 4.5:1. The age-group most affected was the 21-30-year-olds. Road traffic injuries (RTIs) were responsible for 61% (n = 735 of the injuries, interpersonal violence 27.6% (n = 332), accidental falls 12% (n = 142) and firearm injuries 2.2% (n = 27). Of the maxillofacial fractures (n = 1069) isolated mandibular fractures were 62%, isolated mid-facial fractures 24% whereas Pan-facial fractures accounted for 14%. CONCLUSION: The victims of OMFIs were mostly young men between 21 and 30 years of age. The main aetiological factors were road traffic injuries (RTIs) and interpersonal violence (IPV), while the lower third of the face was most often involved. Consistent with findings in other studies, RTI and IPV remain the two main causes of Maxillofacial injuries and public health measures targeting prevention should focus on these areas.

Global oral health inequalities in incidence and outcomes for oral cancer: causes and solutions.

The mouth and oropharynx are among the ten most common sites affected by cancer worldwide, but global incidence varies widely. Five-year survival rates exceed 50% in only the best treatment centers. Causes are predominantly lifestyle-related: Tobacco, areca nut, alcohol, poor diet, viral infections, and pollution are all important etiological factors. Oral cancer is a disease of the poor and dispossessed, and reducing social inequalities requires national policies co-ordinated with wider health and social initiatives - the common risk factor approach: control of the environment; safe water; adequate food; public and professional education about early signs and symptoms; early diagnosis and intervention; evidence-based treatments appropriate to available resources; and thoughtful rehabilitation and palliative care. Reductions in inequalities, both within and between countries, are more likely to accrue from the application of existing knowledge in a whole-of-society approach. Basic research aimed at determining individual predisposition and acquired genetic determinants of carcinogenesis and tumor progression, thus allowing for targeted therapies, should be pursued opportunistically.

Clinico-histopathologic types of maxillofacial malignancies with emphasis on sarcomas: a 10-year review.

BACKGROUND: Sarcomas are malignant neoplasms that occur anywhere in the human body. Though their occurrence in the head and neck region is rare vis-a-vis other malignancies, their presence is of tremendous concern due to their often grave prognosis. OBJECTIVE: To determine the pattern of occurrence, histopathologic types of maxillofacial sarcomas and their proportion to other malignant neoplasms of this region based on archival material accumulated over 10 years (2000-2009). DESIGN: A combined retrospective and prospective cross-sectional study. SETTING: The University of Nairobi Dental Hospital (UNDH). SUBJECTS: All cases with a diagnosis of sarcoma registered between 2000-2009 were evaluated. RESULTS: Of the 528 malignancies recorded over the ten-year period, 427 (80.9%) were of epithelial origin while 101 (19.1%) were sarcomas. Patients with epithelial malignancies were older (54.16 +/- 15.94 years) than patients with sarcomas (31.73 +/- 16.78) with the differences having been statistically significant. Osteosarcoma was the most commonly occurring sarcoma (29.7%), followed by Kaposi's sarcoma (KS) (28.7%), fibrosarcoma (FBS) (18.8%), and rhabdomyosarcoma (RMS) (9.9%). Sarcomas peaked in the third decade with 70% occurring below the age of 40 years. The maxilla and the mandible were the most afflicted sites in the maxillofacial region accounting for 52%. The patients on average presented to medical personel about nine months after noticing the lesion with the most frequent complaint having been swelling. CONCLUSION: The present study confirms the relative rarity of maxillofacial sarcomas. It also provides data on the histopathologic types and demographic characteristics of maxillofacial sarcomas in a select Kenyan population. This information is a contribution to the comprehensive documentation of sarcomas that occur globally and is useful in the provision of baseline data upon which future prospective analytical protocols may arise.

Reactive localised inflammatory hyperplasia of the oral mucosa.

OBJECTIVE: To document the histopathological pattern and distribution of reactive localised inflammatory hyperplastic lesions of the oral mucosa diagnosed at the University of Nairobi Dental Hospital over a 14 year period. DESIGN: A retrospective, cross-sectional descriptive study. SETTING: Division of Oral Pathology and Oral Medicine, histopathology laboratory, School of Dental Sciences, University of Nairobi. SUBJECTS: A total of 3135 oral biopsies were accessioned in the oral diagnostic histopathological Laboratory registry over a period of 14 years from March 1991 to December 2005. RESULTS: Three hundred and thirty three cases were histopathologically diagnosed as reactive inflammatory hyperplasias of the oral mucosa. This constituted 10.6% of the total oral biopsy specimens analysed during this period. Fibrous epulis was the most common histological sub-type with 129 cases (38.7%) followed by pyogenic granuloma with 94 (28.3%) cases. Six (1.8%) cases were peripheral giant cell granuloma and three cases (0.9%) were those of denture irritation hyperplasia. The age distribution ranged from 2 to 78 years (mean = 30.5 years) with a peak at 20-29 years. Gender distribution showed that 107 (32%) cases occurred in males and 226 (68%) cases females. Similar trends were observed in most of the histological sub-types. Fibrous epulis occurred in 41 male (31.8%) cases and in 88 (68.2%) females with an age range of 2 to 78 years (mean = 30.5 years). As for the pyogenic granuloma, 26 (27.7%) lesions occurred in males and 68 (72.3%) in females with an age range of 2 to 75 years (mean = 30.1 years). Among all the histopathological sub-types it was shown that 223 (67.0%) cases were fibrous, 104 (31.2%) vascular and six (1.8%) peripheral giant cell granuloma. Gingival lesions were the most common with 257 (77.2%) cases followed by 28 (8.4%) in the tongue, 16 (4.8%) lips, 15 (4.5%) cheek, six (1.8%) palate and the rest on the floor of the mouth and other mucosal sites. The duration of these lesions was recorded in 182 (54.7%) cases and ranged from 1 week to 16 years (mean = 1.8 years). Only 15 (4.5%) cases were reported to have recurred and all of them were gingival lesions. CONCLUSION: The present study has shown that the prevalence of reactive localised inflammatory hyperplasia (RLIHs) of the oral mucosa was 10.6% with fibrous epulis and pyogenic granuloma having been the most common histopathological sub-types predominantly affecting females. Although RLIHs are distinguished on clinical or histopatholocal grounds, it is important to appreciate that they are variations of the same basic process.

Cigarette smoking and oral health among healthcare students.

BACKGROUND: The knowledge, attitudes and practices of cigarette smoking and health risks among health workers has been found to be predictive of their efficiency as agents for tobacco cessation campaigns. OBJECTIVE: To describe the knowledge, attitudes and practices of cigarette smoking and oral health risks among healthcare professional students. DESIGN: A cross sectional multi-level study. SETTING: College of Health Sciences, University of Nairobi. SUBJECTS: Two hundred and eighty one students. RESULTS: Thirty four (12.1%) of the students were current smokers, 174 (61.95%) had never smoked, while 73 (26%) were former smokers. Seventy nine point four per cent of the current smokers were males and 20.6% were females. Pharmacy students had the highest smoking prevalence at 11 (32.4%), while dental and nursing students had the lowest percentages of current smokers. Differences observed in smoking status of students in the constituent schools of the College of Health Sciences were statistically significant (p = 0.008). Apart from knowledge levels on the association between tobacco consumption and lung cancer (p = 0.142), there were statistically significant differences in the awareness of the severe oral and systemic effects of smoking amongst the four student groups. CONCLUSIONS: There is a need for harmonisation of teaching of oral and systemic effects of smoking so as to impact on the smoking habits and effectiveness of healthcare professional students as agents of smoking cessation programmes.

An audit of oral diseases at a Nairobi centre, 2000-2004.

OBJECTIVES: To describe oral diseases diagnosed in an urban referral centre in Kenya in terms of age, gender and anatomical distribution and to compare this with reports in the literature. METHODOLOGY: A retrospective histopathological audit. SETTING: Oral Pathology Laboratory at the University of Nairobi Dental Hospital, a tertiary referral centre in Kenya. RESULTS: 548 (53.83%) patients were diagnosed with oral and maxillofacial tumours. Benign tumours (mean age +/- SD = 29.93 +/- 18.27 years) peaked in the third decade and tended to affect men at a younger age (p = 0.001). The most common benign tumour was the ameloblastoma (50.23%: n = 109), which predominantly affected the mandible, and also occurred in male patients at a younger age (p = 0.023). Peak incidences for malignant disease were observed in the sixth decade (mean age +/- SD = 46.94 +/- 18.99 years). Oral squamous cell carcinoma (OSCC) was the most common malignant tumour (59.55%; n = 187); occurring in the tongue, floor of the mouth, buccal mucosa and palate. 10.30% of OSCC occurred in patients under 40 years of age. 147 patients presented with cysts, which were mainly (68.10%) of odontogenic origin. Reactive lesions, infections, salivary gland diseases and autoimmune conditions constituted 26.60% of the case load. CONCLUSION: The tendency of oral squamous cell carcinoma to occur in younger age groups may be an indication of carcinogenic factors that could be peculiar to this population. There is an urgent need for the expansion of reporting systems for oral diseases as an integral part of development of appropriate strategies in the improvement of general health in Kenya.

Socio-economic effects of khat chewing in north eastern Kenya.

BACKGROUND: The khat habit is a widespread phenomenon which has in the past two decades spread to parts of Western Europe and North America from Eastern Africa and the Arabian Peninsula. Although khat has been identified as one of the most commonly abused substances in Kenya, restrictions on cultivation, trade and usage have been non-existent since its legalisation in 1977. OBJECTIVE: To describe the socio-economic effects of khat chewing in Ijara District in the North Eastern Province of Kenya. DESIGN: Cross sectional study. SETTING: Ijara District, North Eastern Kenya. SUBJECTS: Fifty respondents were interviewed. RESULTS: Eighty eight percent of the respondents were khat chewers, and the majority (80%) had family members who engaged in the khat habit. There was a general lack of education on the negative effects of khat chewing. Due to reported mood changes and withdrawal symptoms when not chewing khat, many respondents used more than half of their domestic budgets on khat, but few (28%) perceived this as a waste of resources. Fifty four percent of khat chewers typically started the habit during the day, implying a waste of time for productive work. However, only 40% of the persons interviewed admitted that the drug affected work performance negatively. The khat habit was associated with strain on family relationships, anti-social behaviour and health effects such as insomnia. CONCLUSION: In spite of the negative socio-economic impact of khat in Ijara District, khat consumption remains a widespread habit.

Khat (Catha edulis)-induced apoptosis is inhibited by antagonists of caspase-1 and -8 in human leukaemia cells.

Khat chewing is a widespread habit that has a deep-rooted sociocultural tradition in Africa and the Middle East. The biological effects of khat are inadequately investigated and controversial. For the first time, we show that an organic extract of khat induces a selective type of cell death having all morphological and biochemical features of apoptotic cell death. Khat extract was shown to contain the major alkaloid compounds cathinone and cathine. The compounds alone and in combination also induced apoptosis. Khat-induced apoptosis occurred synchronously in various human cell lines (HL-60, NB4, Jurkat) within 8 h of exposure. It was partially reversed after removal of khat and the effect was dependent on de novo protein synthesis, as demonstrated by cotreatment with cycloheximide. The cell death was blocked by the pan-caspase inhibitor Z-VAD-fmk, and also by submicromolar concentrations of Z-YVAD-fmk and Z-IETD-fmk, inhibitors of caspase-1 and -8, respectively. The 50% inhibition constant (IC(50)) for khat (200 microg ml(-1))-induced apoptosis by Z-VAD-fmk, Z-YVAD-fmk and Z-IETD-fmk was 8 x 10(-7) M as compared to 2 x 10(-8) M and 8 x 10(-8) M, respectively. Western blot analysis showed a specific cleavage of procaspase-3 in apoptotic cells, which was inhibited by Z-VAD-fmk. The cell death by khat was more sensitively induced in leukaemia cell lines than in human peripheral blood leukocytes. It is concluded that khat induces a rather swift and sensitive cell death by apoptosis through mechanisms involving activation of caspase-1, -3 and -8.

Catha edulis (Khat) induces cell death by apoptosis in leukemia cell lines.

Khat is the Celastraceus edulis plant, a flowering evergreen tree or large shrub, which grows in the Horn of Africa and southwestern Arabia. Khat use has been associated with development of oral cancer, but its molecular effects remain controversial. This study describes a novel cytotoxic effect of whole khat extract on three leukemia cell lines. Cells were exposed to khat extract and harvested for analysis by fluorescent and electron microscopy, trypan blue exclusion, as well as immunoblotting to characterize the mode of cell death. In a separate series, cells were pretreated with a panel of caspase inhibitors for possible inhibitory effects. Khat induced a rapid cell death effect in HL-60, Jurkat, and NB4 cells that occurred within 2 h of exposure. The treated cells retained their ability to exclude trypan blue dye, a key feature in the apoptotic process. Exposed cells consistently developed morphological features of manifest apoptosis. Z-VAD, a pan-caspase inhibitor, completely inhibited toxic activity for up to 8 h, with partial inhibition by other caspase-specific agents. Western blot analysis showed specific cleavage of caspase-3 in khat-exposed cells. This study shows that khat induces cell death by apoptosis in a process sensitive to inhibition by caspase inhibitors, suggesting that subcellular interactions could be of particular relevance for the biological effects of khat in the cell death process and possibly carcinogenesis.

Neural tumours of the head and neck.

OBJECTIVE: To document the pattern of occurrence of all primary neural tumours arising in the neck and craniofacial region over the period 1982 to 1991. DESIGN: A retrospective study. SETTING: Cancer Registry, Nairobi, Kenya. RESULTS: Out of the 289 cases who were identified to have had whole body neural tumours, 225 (77.8%) had the lesions distributed in the neck and craniofacial area. While 80% of the neoplasms located in this region were retinoblastomas (mainly occurring in the age group 0 to 4 years), other lesion types occurred in small numbers thus: neurofibromas comprised 12.4%, Schwannomas four per cent, neuroblastomas and neuromas each 0.4%; and extracranial gliomas 2.7%. Overall, the male to female ratio was 1:1 and the site distribution revealed that over 90% of the lesions afflicted the upper face. CONCLUSION: Neural tumours of the neck and craniofacial region appear generally rare in this population as has been shown elsewhere.