Susceptibility of cariogenic Streptococcus mutans to extracts of Garcinia kola, Hibiscus sabdariffa, and Solanum americanum.

BACKGROUND: The elimination of cariogenic bacteria from the oral cavity using antibacterial agents is one of the primary strategies for the prevention of dental caries. Avariety of plants with potent activity are known to be used in indigenous communities for dental hygiene worldwide. OBJECTIVE: To determine if Hibiscus sabdariffa, Solanum americanum and Garcinia kola can inhibit the growth of cariogenic bacteria in the mouth. METHODS: Methanol and aqueous extracts obtained from three plants, Hibiscus sabdariffa, Solanum americanum and Garcinia kola were studied for their antibacterial activity against cariogenic Streptococcus mutans obtained from patients with clinically identified carious lesions, using the agar dilution method. The sources of extracts for Garcinia, Hibiscus and Solanum were respectively fruits and leaves for the latter two. RESULTS: The extracts (both methanol and aqueous) from Garcinia kola showed the most intensive activity and completely inhibited the growth of the primary cariogenic Streptococcus mutans at 1.25 mg/ml. Hibiscus sabdariffa was also active at a minimum inhibitory concentration (MIC) of 2.5mg/ml while Solanum americanum did not show any direct effect on S. mutans. CONCLUSION: The result of this study showed that G. kola and H. sabdariffa have direct antibacterial effect on Streptococcus mutans.

Evaluation of nucleolar organizer regions in tumours of the jaw bones.

Nucleolar organizer regions [NORS] are loops of DNA that transcribe to ribosomal RNA. They can be visualized as intranuclear black dots by histochemical staining with a colloid silver solution. Silver stained nucleolar proteins (AgNORs) were counted in a variety of jaw bone tumours. In osteosarcomas, the number of AgNORs was also quantified before and after chemotherapy. Malignant bone tumour cells possessed more than five small AgNORs (5.54 +/- 0.44). Nuclei of benign jaw bone tumour cells had less than three (2. 97 +/-0.61). A significant difference in the number of AgNORs between osteosarcoma before chemotherapy (5.76 +/- 0.50) and after chemotherapy (3.89 +/- 1.65) was observed. (P < 0.05). The number ofAgNORs in recurrent osteosarcoma, recurrent ameloblastic carcinoma and recurrent chondrosarcoma was much higher than in their respective primary lesion but without statistical significant difference. The results of the present study indicate that the AGNOR count might help in determining malignancy, evaluating the effect of chemotherapy, and deciding the prognosis.

Nucleolar organizer regions in jaw tumours of cartilaginous origin.

Nucleolar organizer regions [NORs] are loops of DNA that transcribe to ribosomal RNA. They can be visualized as intranuclear black dots by histochemical staining with a colloid silver solution. Silver-stained nucleolar proteins [AgNORs] were counted in cases comprising of primary chondrosarcomas of three histologic grades, in chondromyxoid fibroma and in controls comprising of normal bone and cartilage tissues of the jaw bones. The AgNOR counts increased step-wisely from normal bone tissue [1.11 0.4], chondromyxoid fibroma [2.66 0.78], grade I chondrosarcoma [3.94 0.34], grade II chondrosarcoma [4.32 0.52], and grade III chondrosarcoma [5.54 0.44]. There was a statistically significant difference in the mean AgNOR counts between grade 1 and grade III chondrosarcoma [p < 0.05]. The mean AgNOR counts for benign cartilaginous [chondromyxoid fibroma] tumour was significantly lower than the mean, AgNOR count for malignant cartilaginous tumours [chondrosarcomas] [p < 0.05]. The results in the present study indicate that silver colloid staining is a useful technique for evaluating the proliferative activity of chondrosarcoma and benign cartilaginous tumour such as chondromyxoid fibroma.