Cysts and tumors of the jaws treated by marsupialization : a description of 4 clinical cases

Since the 4th edition of the World Health Organization?s Classification of Head and Neck Tumours was published in January of 2017, the keratocystic odontogenic tumor is back into the cyst category as odontogenic keratocyst (OKC). Depending on the size of the cyst, its location and the patients? age, several treatment options are available: curettage, enucleation, radical treatment and marsupialization. The marsupialization is a conservative technique used in early tumor stages, as curative treatment for the odontogenic cyst. Despite its disadvantages and controversies, the marsupialization remains an interesting therapeutic choice in the case of large cysts, or in very young or old patients. We describe, in this article, four clinical cases of odontogenic cysts. We report the surgical management and the subsequent evolution of the patients. The discussion focuses on the indications, advantages and limitations of the odontogenic cyst?s marsupialization. We review the specific conditions of the odontogenic cysts that could make the marsupialization the optimal therapeutic option. In our cases, the marsupialization proved to be a conservative technique which allowed the respect of neighboring anatomical structures, particularly in the case of large cysts, but requires prolonged clinical and radiological monitoring. Pathological entity for our cases was different. Thus, the treatment outcome may be different too. This series is very small and the reader should be cautious about drawing broad conclusions regarding the optimal therapeutic choice

Isolation and Characterization of Hydrocarbon-Degrading Yeast Strains from Petroleum Contaminated Industrial Wastewater

Two yeast strains are enriched and isolated from industrial refinery wastewater. These strains were observed for their ability to utilize several classes of petroleum hydrocarbons substrates, such as n-alkanes and aromatic hydrocarbons as a sole carbon source. Phylogenetic analysis based on the D1/D2 variable domain and the ITS-region sequences indicated that strains HC1 and HC4 were members of the genera Candida and Trichosporon, respectively. The mechanism of hydrocarbon uptaking by yeast, Candida, and Trichosporon has been studied by means of the kinetic analysis of hydrocarbons-degrading yeasts growth and substrate assimilation. Biodegradation capacity and biomass quantity were daily measured during twelve days by gravimetric analysis and gas chromatography coupled with mass spectrometry techniques. Removal of n-alkanes indicated a strong ability of hydrocarbon biodegradation by the isolated yeast strains. These two strains grew on long-chain n-alkane, diesel oil, and crude oil but failed to grow on short-chain n-alkane and aromatic hydrocarbons. Growth measurement attributes of the isolates, using n-hexadecane, diesel oil, and crude oil as substrates, showed that strain HC1 had better degradation for hydrocarbon substrates than strain HC4. In conclusion, these yeast strains can be useful for the bioremediation process and decreasing petroleum pollution in wastewater contaminated with petroleum hydrocarbons

Pilot-scale petroleum refinery wastewaters treatment systems: performance and microbial communities' analysis

This study evaluated firstly the performance of the Continuous Stirred Tank bioReactor system (CSTR) for the treatment of highly toxic petroleum refinery wastewaters at the pilot-scale. The reduction of the COD, BOD5, phenols, and the total petroleum hydrocarbon (TPH) reached 82.10%, 85.87%, 91.63%, and 81.11%, respectively at high hydraulic residence time (HRT = 10 days). Decreasing HRT to 5 and 2.5 days led to a decrease in the efficiency of the process and a decrease in biomass concentration was also observed (<1000 mg/l). We investigated to test Membrane Bioreactor (MBR) configuration inoculated with the same microbial consortium of CSTR. Therefore, the removal efficiency reached 89.14% of COD and biomass concentration increased to 2800 mg/l at HRT = 1 day. Microbial biomass showed high acclimatization to the toxic wastewater. Communities' abundance and composition in CSTR and MBR were then performed using culture-independents approaches (qPCR, Illumina Miseq sequencing, and DGGE) based on the 16S rRNA gene sequencing. Results showed that major genera affiliated with Betaproteobacteria and Gammaproteobacteria were commonly shared in both bioreactors. The MBR presented a higher bacterial abundance and diversity than the CSTR. Furthermore, dominant genera belonging to Alphaproteobacteria and Bacteroidetes were exclusively detected in CSTR and MBR, respectively. Six potential hydrocabonclastic bacteria were isolated from the CSTR. This study demonstrates the occurrence of specific acclimated bacterial communities in MBR different from those identified in CSTR, improving the petroleum hydrocarbon wastewater treatment. The results would be useful in developing an MBR system for treating toxic stripped wastewater at a larger scale

Inclusion ectopique d'une dent de sagesse mandibulaire. A propos d'une observation

L'inclusion des dents de sagesse représente une pathologie fréquente en stomatologie et chirurgie maxillofaciale. Cependant, l'inclusion en position ectopique est rare. Nous rapportons le cas d'une ectopie de la dent de sagesse inférieure gauche dans la branche montante, proche de l'échancrure sigmoïde. Il s'agit d'un patient âgé de 42 ans qui a été adressé pour une cellulite de la région parotidienne gauche. Les explorations radiologiques ont montré une dent de sagesse inférieure gauche siégeant au niveau de l'échancrure sigmoïde avec un kyste péricoronaire. L'état local s'est amélioré par une antibiothérapie pendant 15 jours. Un mois après, l'extraction de la dent a été pratiquée par voie endobuccale. La conduite thérapeutique devant une dent de sagesse mandibulaire ectopique nécessite une bonne réflexion. Le choix de la voie d'abord dépend du siège de la dent et de l'expérience du chirurgien. Pour les cas asymptomatiques, l'abstention chirurgicale est conditionnée par une surveillance régulière. (Med Buccale Chir Buccale 2009 ; 15 : 45-48)