Physicochemical factors affecting the diversity and abundance of Afrotropical Culicoides species in larval habitats in Senegal.

Biting midges of the genus Culicoides (Diptera: Ceratopogonidae) are the biological vectors of arboviruses of global importance in animal health. We characterized the physicochemical parameters that determine the density and composition of the main Culicoides species of veterinary interest in larval habitats of the Niayes region of Senegal. For this purpose, we combined larval and substrate sampling in the field in different habitat types with adult emergence and physicochemical analyses in the laboratory. Three major habitat types were identified, conditioning the predominant species of Culicoides and pH and the amount of organic matter were positively correlated with the abundance of larvae and emerging Culicoides, as opposed to salinity. The diversity of emerging Culicoides was positively correlated with pH while it was negatively correlated with salinity. Culicoides distinctipennis was the predominant species in the larval habitat group of freshwater lake edges. In the larval habitat group of pond and puddle edges, C. oxystoma and C. nivosus were predominant; both species were again most abundant in the larval habitat group of saltwater lake edges. These variabilities in physicochemical parameters support the distribution of different Culicoides species in different habitat groups. These results make it possible to implement effective, selective and environmental-friendly control measures but also to improve current models for estimating the abundance of adult vector populations at a local scale.

Foraging range of arthropods with veterinary interest: New insights for Afrotropical Culicoides biting midges (Diptera: Ceratopogonidae) using the ring method.

The identification of blood meal source of arthropod vector species contributes to the understanding of host-vector-pathogen interactions. The aim of the current work was to identify blood meal source in Culicoides biting midge species, biological vectors of internationally important arboviruses of livestock and equids, using a new ecological approach. We examined the correlation between blood meal source identified in engorged Culicoides females collected in a suction light trap and the available vertebrate hosts along four rings (200, 500, 1000 and 2000 m) centered at the trap site and described the foraging range of the three main vector species of veterinary interest present in the study area, Culicoides imicola, Culicoides kingi and Culicoides oxystoma. The study was performed in four sites localized in the Niayes region of Senegal (West Africa) where recent outbreaks of African horse sickness occurred. Blood meal source identification was carried out by species-specific multiplex PCRs with genomic DNA extracted from the abdomen of engorged females collected during nine night collections for twenty-six collections. The four most abundant hosts present in the studied area (horse, cattle, goat and sheep) were surveyed in each ring zone. The blood meal source varied according to Culicoides species and host availability in each site. C. oxystoma and C. imicola females mainly fed on horses readily available at 200 m maximum from the trap location whereas females of C. kingi fed mainly on cattle, at variable distances from the traps (200 to 2000 m). C. oxystoma may also feed on other vertebrates. We discuss the results in relation with the transmission of Culicoides-borne arboviruses and the species dispersion capacities.

Importance of vector-borne infections in different production systems: bovine trypanosomosis and the innovation dynamics of livestock producers in Senegal.

In Senegal, a project has been undertaken to eradicate a population of tsetse flies (Glossina palpalis gambiensis) from a prime area for intensifying livestock production--the coastal region of Niayes. The project is intended to remove the constraint of trypanosomosis and allow the ecological intensification of cattle production. A cross-sectional analysis of ten case studies was the inductive phase of an assessment to gauge the impact of removing trypanosomosis on livestock production strategies. The methodology used was comprehensive analysis, with participatory epidemiology tools to understand farmers' rationales. The authors analysed the strategies of three main types of livestock producer (agro-pastoralists, mixed crop/livestock farmers and intensive dairy farmers). The strategies were in line with the farmers' goals and their ability to mobilise the socio-technical network. The risk management of trypanosomosis has been incorporated into livestock management practices through the use of trypanotolerant breeds, medical prophylaxis or placing livestock in low-risk areas. Removing the risk of disease would therefore have a major impact on decisions about the composition and strategic direction of herds. This change in the animal health environment would steer livestock production along different routes of intensification in a highly competitive environment. The indicators of innovation capacity revealed by this study will be used to quantitatively monitor various change scenarios, taking livestock producers' reasoning into account, in order to assess the socio-economic impact of eradicating the tsetse fly population in this area. The methodology presented in the study can be used to understand the impact of controlling other vector-borne infections on the innovation dynamics of livestock producers.

[Relationship between bizygomatic width and the size of maxillary anterior teeth among young Senegalese black people recruited in army]. / Corrélation entre la distance bizygomatique et la largeur des dents antéromaxillaires chez les jeunes sénégalais mélanodermes recrutés dans le service militaire.

INTRODUCTION: Prosthetic teeth size and placement must be in perfect harmony with the bucco-facial structures for a successful and esthetic removable prosthesis. This study aimed to determine among young Senegalese black people facial index estimating maxillary central incisor width and distance between canine points starting from bizygomatic width. PATIENTS AND METHODS: 621 black Senegalese participated to this transversal study. Measurements were made using anthropometric slide caliper and electronic slide caliper. The comparative analysis was carried out by the test t of Student. The correlative analysis used the chi-square test. The risk of error was fixed at 5%. RESULTS: Positive correlations were found between variables. Distance between canine points was significantly (p = 0.000) correlated to bizygomatic width and central incisor width. Using bizygomatic width, the average dividing factors to estimate central incisor width and distance between canine points were respectively 15.13 and 3.75. CONCLUSION: Distance between canine points and central incisor width can be given starting from bizygomatic width, as guide of selecting maxillary anterior prosthetic teeth width.

[Correlations between colorimetric parameters of teeth, eyes and skin. Perspectives in the choice of tooth shade for complete denture]. / Correlations entre les parametres colorimétriques des dents, des yeux et de la peau. Perspectives dans le choix de la teinte des dents en prothèse adjointe complète.

Rehabilitation with complete denture include among other objectives, improvement of facial and dental esthetics. To these ends, the artificial teeth should mimic as far as possible, healthy and natural dentition. The main objective of this study was to investigate factors associated with tooth color among black African subjects. One hundred and two subjects (72 men and 30 women) were included in this investigation. The colorimetric parameters of their teeth as well as those of the conjunctiva of their eyes and skin were recorded from standardized photographs. Two software, Mesurim and Photoshop were used for that purpose. Univariate and linear regression analysis were run to assess the association between tooth color and the variables age, gender and colorimetric parameters of eyes and skin. It appears from the result of this study that tooth color was positively and significantly associated with age. Stepwise multiple regression analysis further revealed that tooth hue can be best predicted by a combination of skin complexion and brightness and eye lightness.

[Prevalence of halitosis in patients with dental prostheses in Senegal]. / Prevalence de l'halitose chez des patients sénégalais porteurs de prothèses dentaires.

INTRODUCTION: Bad breath is a disease affecting 25% of the world's population. Despite the widespread nature of this problem, people's knowledge about this condition is poor. OBJECTIVE: The purpose of this study was to determine the prevalence of halitosis in a cohort of 62 Senegalese subjects with dental prostheses. METHODS: Breath analysis was based on measurement of volatile sulfur compounds (VSC) using a halimeter. Halitosis was diagnosed ifVSC level was > or = 125 ppb. RESULTS: Mean VSC level was 157.7 +/- 152.6 ppb. The prevalence of halitosis was of 35.4% overall, 72.7% in persons with fixed dentures and of 27.3% in persons with removable prostheses. CONCLUSION: The relatively high prevalence of halitosis observed in this study indicates a need to enhance patient awareness of daily hygiene measures for dental prosthesis.

[Prosthetic rehabilitation: needs in Senegalese dental offices]. / La réhabilitation prothétique: évaluation des besoins dans les cabinets dentaires du Sénégal.

Knowledge of dental prosthetic needs will develop strategies for prevention and treatment through a package of individual, community and professional policies. The aim of this study was to evaluate prosthetic needs in Senegalese dental offices. The survey was conducted among people aged 15 years and more attending Senegalese dental clinics. The mean number of missing teeth was 4.4. Only 55.3% of the sample expressed the need for dentures and 81.8% had a diagnosed need for prosthesis. A statistically significant difference was noticed between the needs diagnosed and the expressed needs (p < 0.0001). Finally, this study reveals that the need for prosthetic treatment is real in the Senegalese dental offices.

The prevalence of African animal trypanosomoses and tsetse presence in Western Senegal.

In 2005, the Government of Senegal initiated a tsetse eradication campaign in the Niayes and La Petite Côte aiming at the removal of African Animal Trypanosomosis (AAT), which is one of the main constraints to the development of more effective cattle production systems. The target area has particular meteorological and ecological characteristics that provide great potential for animal production, but it is unfortunately still infested by the riverine tsetse species Glossina palpalis gambiensis Vanderplank (Diptera: Glossinidae). The tsetse project in Senegal has adopted an area-wide integrated pest management (AW-IPM) approach that targets the entire tsetse population within a delimited area. During the first phase of the programme, a feasibility study was conducted that included the collection of entomological, veterinary, population genetics, environmental and socioeconomic baseline data. This paper presents the parasitological and serological prevalence data of AAT in cattle residing inside and outside the tsetse-infested areas of the target zone prior to the control effort. At the herd level, a mean parasitological prevalence of 2.4% was observed, whereas a serological prevalence of 28.7%, 4.4%, and 0.3% was obtained for Trypanosoma vivax, T. congolense and T. brucei brucei, respectively. The observed infection risk was 3 times higher for T. congolense and T. vivax in the tsetse-infested than in the assumed tsetse-free areas. Moreover, AAT prevalence decreased significantly with distance from the nearest tsetse captured which indicated that cyclical transmission of the parasites by tsetse was predominant over mechanical transmission by numerous other biting flies present. The importance of these results for the development of a control strategy for the planned AW-IPM campaign is discussed.

[Relationships between masticatory performance and nutritional state in complete denture wearers]. / Relations entre Performance Masticatrice et Etat Nutritionnel chez des Sujets Porteurs de Prothèses Complètes.

UNLABELLED: For many authors masticatory dysfunctions are related to reduction in dietary intake with malnutrition as a possible consequence. The aim of the present study was to further investigate the relationships between masticatory performance and nutritional state in complete denture wearers. METHOD: Masticatory performance was assessed using a granulometric method in 74 subjects divided into 2 subgroups according to their dental status (normal dentition and complete dental wearers). Nutritional status of study subjects was analyzed with Mini Nutritional Assessment (MNA). RESULTS: There were a significant association between wearing denture and Nutritional Status as assessed by MNA. Using this scale, a risk of malnutrition was found in 80% of subjects wearing complete denture and in 26% in the normal dentition sub group (p < 0.0001). There were also a positive and significant correlation between, the particle size distribution and masticated test food and nutritional status. CONCLUSION: Complete denture wearers are at greater risk of malnutrition than did subjects with normal dentition.

[Study of mastication in denture wearers among various ages]. / Etude des parametres physiologiques de la mastication chez des sujets ages porteurs de protheses adjointes completes.

INTRODUCTION: Recent studies have shown that it was possible for subjects with masticatory deficiency chewing achieve a satisfactory level of fragmentation of food by acting on some physiological parameters as the number of cycles and the time devoted to a sequence of mastication. METHOD: The objective of this work is to study the effects of the wearing of complete prostheses, of ageing on the physiological parameters from the chewing on a population of 110 subjects. RESULTS: The results show an important effect of the dental status. Indeed denture weaers need twice more cycles than controls of the same age to make a ham portion ready to be swallowed. Significant an age effect with regard to the number of cycles was also noted. The rheology of food affects the number of cycles which increases with the hardness of food.

[Study of the characteristics of the food bolus in elderly subjects with complete dentures]. / Etude des caractristiques du bol alimentaire chez des sujets agés porteurs de prothèses complètes.

Many studies have shown that wearing of complete dentures impairs masticatory function. The aim of this study was to investigate the influence of complete denture wearing and ageing on masticatory performance. Masticatory performance was assessed by a granulometric method on 110 subjects divided into 3 groups according to dental state and age. The results show edentulous subjects have a masticatory performance worse than their congeneric of the same age. Indeed, the median of the distribution of the size of the particles is more important at the carriers of prostheses than at the toothed old subjects (P < 0.0001). On the other hand the extent of the distribution does not vary significantly between these 2 groups of subjects. The parameters of the masticatory performance do not vary in a statistically significant way between the old subjects and the young controls. There is thus no significant effect of the age on the parameters of the performance masticatory.

[Carmyerius marchandi, a new species of trematode (Gastrothylacidae), a parasite of cattle in Senegal]. / Carmyerius marchandi, nouvelle espèce de trématode (Gastrothylacidae), parasite des bovins au Sénégal.

Carmyerius marchandi n. sp., a new species of trematode (Paramphistomoidea, Gastrothylacidae), has been described in Senegal. It has an average length of 13 +/- 1 mm and an average diameter of 3 +/- 0.4 mm. The brood pouch, bearing muscular invaginations and a ventrolateral swelling, makes up two thirds of the body length. There is a Carmyerius-type acetabulum. The ratio between the diameter of the acetabulum and body length is 1:7.4. The trematode has a Gastrothylax-type pharynx. The ratio between pharynx length and body length is 1:13.3. The ratio between pharynx length and acetabulum diameter is 1:1.8. The caeca extend beyond the mid section of the parasite. The lobed testicles are in a lateroposterior position. The ovary is situated between the two testicles and the uterus is in a mediodorsal position. The vitelline glands take up a large area in the ventrolateral swelling of the brood pouch. The small genital atrium is of the elongatus type. Using scanning electron microscopy, the parasite's body shows transverse ridging and tegumentary papillae around the oral aperture, genital pore and acetabulum. All of these characteristics indicate that this Gastrothylacidae belongs to the Carmyerius genus. To judge by the other species in the genus previously described, this appears to be a new species. We suggest that it should be named C. marchandi n. sp., as a token of gratitude to Professor Bernard Marchand.

[Evaluation of rehabilitation needs by post-maxillectomy prosthesis in Senegal]. / Evaluation des besoins de réhabilitation par prothèse maxillo-faciale obturatrice après maxillectomie au Sénégal.

The surgical treatment of the jawbone tumors often ends up with an communication between the mouth and the sinus, embarrassy for the function and carrying severe esthetical damages. This work aims to evaluate the needs in filling mouth and fixe treating prosthesis in the management of malignant tumors at the Dantec University hospital. A case study of maxillary jawbone cancers observed in the ORL and the stomatology services allowed us to observe on a ten years period, 91 cases of maxillary cancers, from which (29 or 31.86%) have been surgically treated and only 3 patients (3.29%) got a full mouth and face filling prosthesis. Those patients averaged 50 years old, but we have registered some younger patients and women who, having missed oral rehabilitation, are really handicapped. In Senegal the care of people suffering from jawbone cancers must include a surgical section as well as a radiotherapeutic one, in order to involve all the cases, and a filling mouth-and-face rehabilitation prosthesis.

[Clinical evaluation of the occlusion of young Senegalese]. / Evaluation clinique de l'occlusion de jeunes Sénégalais.

The dental occlusion is a basic phase of mastication moreover it is an everlasting concern for the dentist during therapeutic and prevention of dento-maxillo-facial disorders. Senegal is a country of recent dental practice and dental problems are frequent in it. We led this clinical assessment of occlusion on a sample of 30 young Senegalese people aged 18 to 35 years and we tried to evaluate the consequential effects on teeth and periodontal tissues with intent to use this study as pattern of prevalence evaluation of occlusion disorders. Taken at random in the consultation at the Institute of Odontology and Stomatology, these people have been selected by excluding any obvious cause of occlusal disorders. 76.67% of our sample are students and the average patient of the study is à 24 years man, wolof, student dwelling in Dakar. He has an avoid face, is in normocclusion or prognathia and presents a tooth affection which can be related to malocclusion and defective hygiene. 67% of examined teeth are in contact during maximal occlusion and 33% are in entire lack of posterior contact during protrusion meanwhile 73 to 80% present group function. In 70% of studied cases, the superficial periodontium is affected and 30% representing the deep periodontium, are quite safe. This word is a first attempt of prevalence evaluation. It has to be led in multicentric study and at a larger scale in order to have more exact sight of young Senegalese occlusal disorders.

[Gingival risks of fixed prostheses at the Institute of Odontology and Stomatology of Dakar (I.O.S.)]. / Etude du risque parodontal superficiel en prothese fixee a L'Institut d'Odontologie et de Stomatologie de Dakar (I.O.S.).

The realisation of a bridgework involves a direct action on the gingival marginal edge. It is submitted to peremptoriness of execution that one of the objectives is to respect the periodontium with a great rigour. In the opposite case it can become a greater aggression agent, source of prosthetic failures we carried out this report in order to evaluate in the framework of a pedagogic operational programme of crown and bridge prosthesis, the superficial periodontal risks linked to the preparation of the abutment teeth and to the prosthetic chain. We examined a randomised sample of 50 patients chosen from the Dakar LOS prosthetic consultation. On the periodontium initially sound we noted inflammatory lesions of the superficial periodontium from the beginning to the end of the treatment we used the Russel periodontal index. The whole individual scores summarised on a collective chart have been submitted to the statistical analysis of the independence by using the chi-square test. The population consulting in bridge work at the Dakar LOS is relatively young, 33 years in a average with a sex ratio of 1.17 and it shows a moderate (60% of the cases) and severe periodontal seizure (40% of the cases) dealing significantly with the type of prosthesis and the axial and occlusal morphology of the prosthesis pieces. This study shows that prosthesis rehabilitation in the frame work of a clinical training at the Dakar I.O.S. includes relatively high risks of periodontium aggression that we would minimise by setting more correctly the indications of the bridge work and by bringing more rigour to the record and the postpone of the patients occlusion in the laboratory conception of the prosthesis pieces.

[Effect of the quality of endodontic treatment on the longevity of fixed prostheses. Apropos of 64 pulpectomies]. / Incidence de la qualite des traitements endodontiques sur la perrenite de la prothese conjointe. A propos 64 pulpectomies.

64 teeth with well-fitting post-retained crown were examined radio graphically and clinically and a number of failures were assessed including the peri-apical condition and the quality of root filling. All the teeth were vital and prosthetic was the only reason of endodontic treatment. Results have shown that 25% of the teeth had areas of radiolucency around the root apices. Various criteria parameters were reviewed for possible correlation to the failures. 15 out of the 16 cases of failures could be related to the endodontic therapy procedures: lack of using a rubber dam during the treatment and an unsatisfactory condensed and sealed root filling. Only one case was related to the deviation of post from the line of canal suggest a lateral perforation. To perform a post-retained crown the quality of endodontics must be considered: the operative procedures should be more controlled and enough time should be observed after root canal therapy to ensure its successful.

Etude comparative du risque traumatique dento-maxillaire en pratique sportive au Senegal : a propos de 600 sportifs

"Les auteurs ont mene une etude comparative de prevalence des traumatismes bucco-dentaires dans la ""lutte avec frappe"" et dans certains sports d'equipe ou individuels comme le football; le basket ball; la boxe anglaise et la lutte libre. L'objectif de cette etude est d'informer; d'eduquer; de communiquer avec le milieu sportif senegalais; mais aussi de prevenir les risques potentiels du sport par le port de gouttieres de protection dento-maxillaires"

[Complete removable dentures and the elderly at I.O.S., Dakar]. / Prothèse adjointe complète et troisième âge à l'I.O.S. de Dakar.

INTRODUCTION: At I.O.S. Dakar, we have taken an essential interest in elderly persons with functional disorders, aesthetic and psychological. We have fixed the following objectives: to evaluate the importance of the elderly person in our surgery to define the major characteristics of this category of patient to single out the specific aspects of the restorative denture to make our teaching programmes more relevant. MATERIALS AND METHODS: Two complementary axes: a retrospective statistical descriptive study carried out on the records of patients at P.A.C. of I.O.S. during the previous three academic years of patients at P.A.C. of I.O.S. during the previous three academic years 1986-87, 88-89, 89-90. an analysis of the records based on the following variables: age, sex, place of living, occupation, type of complete attached dentures additionally, certain particular aspects of these patients have been studied. SELECTION CRITERIA: We have studied patients over 55 years of age who have either a single or bimaxillary replacement. VARIABLES STUDIED: two types of denture: unimaxillary CAD and bimaxillary CAD our patients were classed as: urban--living in Dakar and Gorée rural--coming from surrounding villages suburban--those coming from Pikine, Parcelles Assainies, Rufisque. for occupation: first sector--agriculture, fishing second sector--industrial or conversion workers third sector--service workers or tradesmen, housewives, pensioners, others. RESULTS AND COMMENTARY: the sex ratio is closely akin to that of the general population the majority of patients live in Dakar these are mainly housewives, retired people who could regularly attend our consultations and stay the course of our treatment, prosthetic restorations are complete attached bimaxillary dentures (79.14%). Clinical specifications: On a local clinical level, the total toothlessness of the elderly presents as: a muscular hypotomy, a loss of the vertical dimension of occlusion, a marked increase in nasal and oral fissures, a stiffening of the articular structures, a great reduction of osteo-mucus in the residual edges, a spreading of the tongue which invades the oral cavity, a loss of occlusive memory, Bearing on therapy and teaching: good clinical observation, constant reference to the medical services, appropriate surgery prior to denture fitting. CONCLUSION: This study shows us that at I.O.S. Dakar, persons over 55 coming to consult us are most often city dwellars and often housewives or retired people. The major purpose of these visits is functional. The minute failure rate encountered over these three years has led us to believe that prosthesis enjoys high esteem thanks to the raised criteria of competence, of knowledge and of the patience of the whole team.