HIV Infection and Exposure Increases Cariogenic Taxa, Reduces Taxonomic Turnover, and Homogenizes Spatial Differentiation for the Supragingival Microbiome.

Background: The oral microbiome comprises distinct microbial communities that colonize diverse ecological niches across the oral cavity, the composition of which are influenced by nutrient and substrate availability, host genetics, diet, behavior, age, and other diverse host and environmental factors. Unlike other densely populated human-associated microbial ecosystems (e.g., gut, urogenital), the oral microbiome is regularly and directly exposed to the external environment and is therefore likely less stable over time. Cross sectional studies of the oral microbiome capture a glimpse of this temporal dynamism, yet a full appreciation of the relative stability, robusticity, and spatial structure of the oral environment is necessary to understand the role of microbial communities in promoting health or disease. Results: Here we investigate the spatial and temporal stability of the oral microbiome over three sampling time points in the context of HIV infection and exposure. Individual teeth were sampled from a cohort of 565 Nigerian children with varying levels of tooth decay severity (i.e., caries disease). We collected 1,960 supragingival plaque samples and characterized the oral microbiome using a metataxonomic approach targeting an approximately 478 bp region of the bacterial rpoC gene. We found that both infection and exposure to HIV have significant effects on the stability of the supragingival plaque microbiome at both the spatial and temporal scale. Specifically, we detect (1) significantly lower taxonomic turnover of the oral community among exposed and infected children compared to unexposed children, (2) we find that HIV infection homogenizes the oral community across the anterior and posterior dentition, and (3) that impaired immunity (i.e., low CD4 count) and low taxonomic turnover over time in children living with HIV is associated with higher frequency of cariogenic taxa including Streptococcus mutans. Conclusions: Our results document substantial community fluctuations over time in children unexposed to HIV independent of oral health status. This suggests that the oral community, under typical conditions, rapidly adapts to environmental perturbations to maintain homeostasis and that long-term taxonomic rigidity is a signal of community dysfunction, potentially leading to a higher incidence of oral disease including caries.

Supragingival mycobiome of HIV-exposed-but-uninfected children reflects a stronger correlation with caries-free-associated taxa compared to HIV-infected or uninfected children.

IMPORTANCE: Globally, caries is among the most frequent chronic childhood disease, and the fungal component of the microbial community responsible is poorly studied despite evidence that fungi contribute to increased acid production exacerbating enamel demineralization. HIV infection is another global health crisis. Perinatal HIV exposure with infection are caries risk factors; however, the caries experience in the context of perinatal HIV exposure without infection is less clear. Using high-throughput amplicon sequencing, we find taxonomic differences that become pronounced during late-stage caries. Notably, we show a stronger correlation with health-associated taxa for HIV-exposed-but-uninfected children when compared to unexposed and uninfected children. This aligns with a lower incidence of caries in primary teeth at age 6 or less for exposed yet uninfected children. Ultimately, these findings could contribute to improved risk assessment, intervention, and prevention strategies such as biofilm disruption and the informed design of pro-, pre-, and synbiotic oral therapies.

Impact of HIV on the Oral Microbiome of Children Living in Sub-Saharan Africa, Determined by Using an rpoC Gene Fragment Metataxonomic Approach.

Children living with HIV have a higher prevalence of oral diseases, including caries, but the mechanisms underlying this higher prevalence are not well understood. Here, we test the hypothesis that HIV infection is associated with a more cariogenic oral microbiome, characterized by an increase in bacteria involved in the pathogenesis of caries. We present data generated from supragingival plaques collected from 484 children representing three exposure groups: (i) children living with HIV (HI), (ii) children who were perinatally exposed but uninfected (HEU), and (iii) unexposed and therefore uninfected children (HUU). We found that the microbiome of HI children is distinct from those of HEU and HUU children and that this distinction is more pronounced in diseased teeth than healthy teeth, suggesting that the impact of HIV is more severe as caries progresses. Moreover, we report both an increase in bacterial diversity and a decrease in community similarity in our older HI cohort compared to our younger HI cohort, which may in part be a prolonged effect of HIV and/or its treatment. Finally, while Streptococcus mutans is often a dominant species in late-stage caries, it tended to be found at lower frequency in our HI cohort than in other groups. Our results highlight the taxonomic diversity of the supragingival plaque microbiome and suggest that broad and increasingly individualistic ecological shifts are responsible for the pathogenesis of caries in children living with HIV, coupled with a diverse and possibly severe impact on known cariogenic taxa that potentially exacerbates caries. IMPORTANCE Since its recognition as a global epidemic in the early 1980s, approximately 84.2 million people have been diagnosed with HIV and 40.1 million people have died from AIDS-related illnesses. The development and increased global availability of antiretroviral treatment (ART) regimens have dramatically reduced the mortality rate of HIV and AIDS, yet approximately 1.5 million new infections were reported in 2021, 51% of which are in sub-Saharan Africa. People living with HIV have a higher prevalence of caries and other chronic oral diseases, the mechanisms of which are not well understood. Here, we used a novel genetic approach to characterize the supragingival plaque microbiome of children living with HIV and compared it to the microbiomes of uninfected and perinatally exposed children to better understand the role of oral bacteria in the etiology of tooth decay in the context of HIV exposure and infection.

Prevalence and associated factors of enamel developmental defects among Nigerian children with perinatal HIV exposure.

To evaluate the prevalence and pattern of developmental defects of the enamel (DDE) and their risk factors among children born infected with Human Immunodeficiency Virus (HIV) and those born to HIV-infected mothers compared with their unexposed counterparts (i.e., children born to uninfected mothers). This was an analytic cross-sectional study evaluating the presence and pattern of distribution of DDE in three groups of school-aged children (age, 4-11 years) receiving care and treatment at a Nigerian tertiary hospital, comprising: (1) HIV-infected (HI) on antiretroviral therapy (ART) (n = 184), (2) HIV-exposed but uninfected (HEU) (n = 186) and (3) HIV-unexposed and uninfected (HUU) (n = 184). Data capture forms and questionnaires were used to record the children's medical and dental history based on clinical chart review and recall from their parents/guardians. Dental examinations were performed by calibrated dentists blinded to the study grouping. CD4+ (Cluster of Differentiation) T-cell counts were assayed for all participants. The diagnosis of DDE corresponded with the codes enumerated in the World Dental Federation's modified DDE Index. Analyses relied on comparative statistics to determine risk factors associated with DDE. A total of 103 participants distributed among the three groups presented with at least one form of DDE, which indicated a prevalence of 18.59%. The HI group had the highest frequency of DDE-affected teeth (4.36%), while that of the HEU and HUU groups were 2.73% and 2.05%, respectively. Overall, the most encountered DDE was code 1 (Demarcated Opacity), accounting for 30.93% of all codes. DDE codes 1, 4 and 6 showed significant associations with the HI and HEU groups in both dentitions (p < 0.05). We found no significant association DDE and either very low birth weight or preterm births. A marginal association with CD4+ lymphocyte count was observed in HI participants. DDE is prevalent in school-aged children, and HIV infection is a significant risk factor for hypoplasia, a common form of DDE. Our results were consistent with other research linking controlled HIV (with ART) to oral diseases and reinforce advocacies for public policies targeted at infants exposed/infected perinatally with HIV.

Age-specific associations with dental caries in HIV-infected, exposed but uninfected and HIV-unexposed uninfected children in Nigeria.

BACKGROUND: HIV infection and its management confer a substantial health burden to affected individuals and have been associated with increased risk of oral and dental diseases. In this study, we sought to quantify HIV-associated differences in the prevalence and severity of dental caries in the primary and permanent dentition of 4-11-year-old Nigerian Children. METHODS: We used clinical, laboratory, demographic, and behavioral data obtained from an ongoing cohort study of age-matched HIV-infected (HI, n = 181), HIV-exposed-but-uninfected (HEU, n = 177), and HIV-unexposed-and-uninfected (HUU, n = 186) children. Measures of dental caries experience (i.e., prevalence and severity) were based on dmft/DMFT indices recorded by trained and calibrated clinical examiners. Differences in primary and permanent dentition caries experience between HI, HEU, and HUU were estimated using multivariable logistic and negative binomial regression modeling. RESULTS: HI children had significantly higher caries experience (33%) compared to HEU (15%) and HUU (22%) children. This difference persisted in fully adjusted analyses [odds ratio (OR) = 1.6; 95% confidence interval (CI) = 1.0-2.6], was most pronounced in the permanent dentition (OR = 3.4; 95% CI = 1.2-9.5), and mirrored differences in caries severity. While molars were predominantly affected in both primary and permanent dentitions, caries lesion patterns differed between dentitions. Caries severity was significantly associated with hypoplastic primary teeth, gingival inflammation, and lower CD4 counts. CONCLUSIONS: We found that the higher prevalence and severity of dental caries among HI children was driven by increased burden of permanent dentition caries compared to their uninfected counterparts. The dentition-specific associations identified in this study highlight the need to design and implement age-specific caries prevention strategies. These may include intensified oral hygiene regimens aimed at mitigating the cariogenic impact of hyposalivation among HI children. Similarly, the long-lasting impacts of developmental defects of the enamel in the primary and permanent dentitions must not be ignored.

Occupational exposure to sharp injuries among medical and dental house officers in Nigeria.

OBJECTIVE: Sharp injuries constitute important occupational exposure in hospital environment, and perhaps the newly graduated medical and dental students, known as House Officers, in the first twelve months of their practice, are the most vulnerable of all health workers. This study was designed to examine the nature and prevalence of occupational injuries among medical and dental house officers and factors associated with reporting these injuries. MATERIALS AND METHODS: A self-administered questionnaire was used to obtain information on demography, types of exposure, and barriers to official reporting of occupational injuries. One hundred and forty-four medical and dental house officers in 3 government owned hospitals in Edo State, Nigeria participated in the study, between April and May, 2010. Descriptive and multivariable analyses were performed. RESULTS: The overall response rate was 96%. Out of all participants, 69.4% were male; 82.6% were medical house officers. Prevalence of percutaneous injury was 56.9%; where needlestick injury constituted one-third of all injuries. Mean frequency of injury was 1.86±2.24, with medicals having more injuries (p = 0.043). The ward was the most common location for the injury and 14.8% of exposures occurred as a result of lapse in concentration. At least 77.0% did not formally report their injury and perceived low injury risk was the most common reason given (51.67%). CONCLUSION: This study shows that a substantial number of House Officers are exposed to occupational injuries and that the majority of them does not formally report these. Safer work environment may be achieved by implementing adequate educational programs tailored specifically to house officers, and policies encouraging exposure reporting should be developed.

Occupational health issues of oral health care workers in Edo State, Nigeria.

OBJECTIVES: To assess awareness and prevalences of occupational health problems among oral health care workers in Edo State, Nigeria. METHODS: This cross-sectional survey was conducted among oral health care workers working in two tiers of health care delivery in secondary and tertiary government-owned dental centres across Edo State from December 2008 to February 2009. A self-administered questionnaire was used to elicit information on demographic characteristics, awareness and prevalences of occupational problems, and preventive measures. RESULTS: The response rate was 93.8%. Overall, 71.1% of respondents were dentists; other respondent groups included dental nurses and dental surgery assistants (16.7%), dental technologists (8.9%) and dental therapists (3.3%). The occupational health problem for which respondents reported the highest level of awareness was biological hazards (96.7%). The most commonly prevalent occupational health problems were musculoskeletal problems [wrist pain (66.7%), waist pain (76.7%), body pain or weakness (84.4%)]. Infection by biological hazards was reported by 6.6% of respondents, and included infection by HIV/AIDS (2.2%), hepatitis B (1.1%), tuberculosis (1.1%) and other infections (2.2%). Chemical hazards in the form of skin reactions to latex gloves (17.8%), camphorated p-monochlorophenol (CMCP, 8.9%), X-ray (7.8%) and other allergies (5.5%) were reported. A few respondents (2.2%) reported occupation-related malignancies. Overall, 52.2% of respondents possessed a health insurance policy, and 93.3% and 88.9% worked in environments they described as well ventilated and well lit, respectively. A quarter (25.6%) of respondents used a film-holder when taking intra-oral radiographs and 23.3% used protective ear plugs when working in close proximity to noisy machines. CONCLUSIONS: Occupational health issues were significant among oral health care workers in Edo State. Awareness of biological hazards was very high. However, musculoskeletal issues represented the predominant occupational problem, and their potential negative impact necessitates urgent educational and ergonomic intervention.

A survey of orofacial injuries among basketball players.

OBJECTIVE: To determine the prevalence of orofacial injuries among basketball players in Benin City, Nigeria and to survey the athletes' awareness, attitude and use of mouthguards. METHODS: A cross-sectional survey of basketball players in the standard basketball arena in Benin City was conducted between November 2009 and January 2010. A self-administered questionnaire elicited information on demography, the prevalence of oral and facial injuries, distribution of site and cause of orofacial injuries, athletes' knowledge, attitudes and usage of mouthguards. Data were subjected to descriptive statistics and Chi square test. RESULTS: The response rate was 78%. Of the 156 respondents, 79.5% were male and 20.5% female, with a mean age of 23.1 years. The distributions was amateurs (61.5%) professionals (38.5%). The mean number of injuries in previous 12 months was 3.7 ± 1.8. The prevalence of both facial and oral injuries among the respondents was 62.8% with the lip and gingiva most commonly involved respectively. The common causes of the orofacial injury reported were from elbows of opponents, falling and collisions with other players. The prevalence of injury was not significantly associated with demography, category, competition and duration of participation. More than half had heard and seen mouthguards and the coach was the leading source of information. The reasons for non-use of mouthguard were mostly ignorance, non-availability and non-affordability. CONCLUSION: The high prevalence of orofacial injury among basketball players reported in this study justifies the need for multidisciplinary injury prevention interventional approach with emphasis on the rules of the games.

Knowledge and cultural beliefs about the etiology and management of orofacial clefts in Nigeria's major ethnic groups.

OBJECTIVE: To determine the knowledge and cultural beliefs about the etiology and management of orofacial clefts in Nigeria's major ethnic groups. DESIGN: Questionnaires designed to elicit respondents' knowledge and cultural beliefs about the etiology and management of orofacial clefts. SETTING: Northern and southern Nigerian communities where the major ethnic groups reside. PARTICIPANTS: Consenting, randomly selected individuals. RESULTS: There were 650 respondents (350 women and 300 men) from 34 of Nigeria's 36 states; 65.5% were aged 21 to 40 years and 52.5% were married. There were Yoruba (33.7%), Igbo/Bini/Urhobo (40.5%), and Hausa/Fulani (25.8%), with most having attained primary and secondary education. Of those responding, 75% had seen an individual with an orofacial cleft. A significant level of ignorance about the cultural beliefs was found. The Hausa/Fulani considered it mostly an act of God; whereas, the Igbo/Bini/Urhobo and Yoruba groups displayed a greater variety of cultural beliefs. The latter groups implicated witchcraft, evil spirit or devil, the mother, and occasionally the child. Of respondents, 40% knew that surgery was a possible solution, and 22% would recommend a visit to the hospital. Respondents with higher educational attainment produced significantly more scientifically related etiologic factors and accurate treatment options. CONCLUSION: Of respondents, 75% were aware of the existence of orofacial clefts, and a fair knowledge of treatment of orofacial clefts was elicited. Diverse cultural beliefs often may present an obstacle to treatment. Improved awareness about the etiology and management of orofacial clefts is required.

Etiology and pattern of zygomatic complex fractures: a retrospective study.

PURPOSE: To document the etiology and clinical data of patients with fractures of the zygomatic complex seen in two university teaching hospitals in Nigeria and to compare the findings with other studies in the literature. PATIENTS AND METHODS: A six-year retrospective study involving 134 patients with zygomatic complex fractures. These patients were selected from a pool of 960 patients who sustained maxillofacial fractures during the period under review. Recorded were demographic, etiologic and clinical data as well as radiologic findings, treatment and postoperative complications. The Chi-squared test was used to test for significance and p values < 0.05 were regarded as significant. RESULTS: 76.1% were males and 23.9% females. Most (46.3%) patients were aged 21-30 years and road traffic accidents (82.1%) caused the most injuries (p < 0.05). Regarding the site of fracture, 88.8% of the patients had fractures of the zygomatic bone, 8.2% had fractures of the arch, and 3.0% had fractures of both the zygomatic bone and arch. The most frequently associated maxillofacial fracture was mandibular (21.0%). The commonest clinical feature was subconjunctival ecchymosis (63.4%), while the commonest radiologic findings were fractures at the zygomatico-frontal and zygomatico-maxillary sutures (38.8%). The Gillies approach (23.4%) was the commonest method of reduction. CONCLUSION: This study has shown that road traffic accidents are responsible for most zygomatic complex fractures in our environment. Urgent enforcement of road traffic legislation is therefore necessary to minimize zygomatic complex fractures due to road traffic accidents. It also showed a low utilization of technological advances in the imaging and treatment of these fractures. These may play a role in the frequency of postoperative complications.