The prevalence of fifth cusp (cusp of carabelli) in the upper molars in Saudi Arabian school students / Prevalencia de la cúspide mesiopalatina de los molares superiores (tubérculo de carabelli) en estudiantes secundarios de Arabia Saudita

The cusp of carabelli trait was first described by Carabelli in 1842. If present, it is seen on the mesial aspect of the mesiopalatal cusp of the deciduous maxillary second molar or permanent maxillary first, second and third molar. The level of expression varies from a mere pit or groove to a well developed cusp. The objective of this study was to assess the prevalence of this trait in Abha Secondary School boys in the age range of 15-20 years. 917 subjects without caries or fillings (or missing) in permanent upper first (16/26) and second molars (17/27) were selected out of the 3408 students examined. The trait was recorded as present or absent in 16/26 and 17/27 only as most of the students had erupted premolars and unerupted third molars. The trait was present in 41.7 percent of the population out of which 82.2 percent were seen on 16/26 bilaterally. It showed more predilection to permanent maxillary right first molar ­ 39.4 percent than permanent maxillary left first molar ­35.8 percent. Only 3.1 percent of the population had the trait on 17/27. These results are in contrast with the prevalence studies carried out in Riyadh - 57.6 percent and Jeddah - 58.7 percent. Nevertheless, it places the Saudi population in moderate CT prevalence group.

La cúspide o tubérculo de carabelli, fue descrita por primera vez por Carabelli en 1842. Si está presente, se observa en la cara mesial de la cúspide mesio-palatina del segundo molar superior permanente o temporal, segundo y tercer molar permanentes. El nivel de expresión varía desde una simple fosa a una cúspide bien desarrollada. El objetivo de este estudio fue evaluar la prevalencia de este tubérculo en los alumnos de escuelas secundarias de Abha en el rango de edad entre 15-20 años. 917 sujetos sin caries ni obturaciones (o extracción) en los primeros (16/26) y segundos (17/27) molares maxilares permanentes fueron seleccionados entre 3408 alumnos examinados. El tubérculo se registró como presente o ausente en 16/26 y 17/27 de los molares, la mayoría de los estudiantes tenían erupcionados los premolares y no erupcionados los terceros molares. El tubérculo estuvo presente en el 41,7 por ciento de la población estudiada, fuera de la cual se observó en el 82,2 por ciento sobre 16/26 bilateralmente. Hubo mayor predilección por el primer molar permanente del lado derecho, un 39,4 por ciento, en comparación al lado izquierdo, 35,8 por ciento. Sólo el 3,1 por ciento de la población tuvo el tubérculo sobre 17/27. Estos resultados contrastan con los estudios de prevalencia realizados en Riyadh con 57,6 por ciento y Jeddah con 58,7 por ciento. Sin embargo, coloca a la población de Arabia Saudita en el grupo de moderada prevalencia del tubérculo de carabelli.

The antimicrobial effect of 0.1 ppm ozonated water on 24-hour plaque microorganisms in situ

Ozone is a known oxidant present in the atmosphere and is commercially produced by simple ozonizer machines. It is a powerful antimicrobial agent in its gaseous and aqueous forms. Ozone readily dissolves in water and retains its antimicrobial property even in the dissolved state. In this study, the effect of 0.1 ppm ozonated water was analyzed on 24-hour supragingival plaque (SP) samples in situ. SP was collected from the two most posterior teeth in the contra-lateral quadrants before and after a 30-second rinse with either distilled water (control group) or 0.1 ppm ozonated water (test group). The plaque was used to count the number of total bacteria, total anaerobic bacteria, Streptococcus mutans, and Candida albicans on selective agar media. The statistical analysis of the number of colony forming units (CFUs) obtained demonstrated a significant antimicrobial effect of ozonated water on the total bacteria (p = 0.01) and anaerobes (p = 0.02). A reduction in the post-rinse CFU count for Streptococcus mutans was also observed, but the effect was not statistically significant (p = 0.07). The Candida species was only grown from one sample. Ozonated water at the 0.1 ppm concentration was effective in reducing the load of 24-hour plaque bacteria, but it did not eliminate them completely.