Clinical features of multiple primary carcinomas of the oral cavity.

[This retracts the article DOI: 10.3892/etm.2016.3999.].

Clinical features of multiple primary carcinomas of the oral cavity.

The present study aimed to elucidate the clinical characteristics of multiple primary carcinomas of the oral cavity. The clinical records of 1,024 patients who were treated during follow-up for oral cancer at the Department of Stomatology, Henan Provincial People's Hospital, between March 2013 and December 2014 were retrospectively reviewed. The clinical characteristics of 961 patients who developed single primary oral squamous cell carcinoma (SCC) during follow-up and 54 patients who subsequently developed multiple primary carcinomas in the oral cavity were compared. Multiple primary carcinomas exhibited a female predilection, were most prevalent in the gingiva, and tended to show earlier tumor and nodal stages, as compared with single primary carcinomas. The local recurrence rate was higher for multiple primary carcinomas, as compared with single primary carcinomas, and was demonstrated to increase with the number of multiple primary occurrences. The cumulative incidence rates for metachronous second primary carcinomas following the onset of the first carcinoma at 10 years was 8.0%. Recurrence of multiple primary carcinomas did not decrease the survival rates of the patients assessed in the present study. Furthermore, differences were detected in the clinical characteristics between patients with single oral SCC and those with multiple primary oral carcinomas. The results of the present study indicated that early diagnosis and treatment and close long-term follow-up are required for patients with multiple primary oral carcinomas.

[The relationship in growth between A.actinomycetemcomitans and cariogenic bacteria in vitro].

PURPOSE: To investigate the correlation in growth between A.actinomycetemcomitans and cariogenic bacteria of S.mutans, L.acidophilus A.naeslundii A.viscosus in vitro. METHODS: Using improvement agar diffusion method and dual-species (A.actinomycetemcomitans with each of cariogenic bacteria) incubation in BHI broth, we studied the relationship between A.actinomycetemcomitans and 4 kinds cariogenic bacteria in growth. The characteristic and percentage of A.actinomycetemcomitans in dual-species biofilms were detected with SEM and CFU(colony forming units).The data were analyzed for significance using an independent two-sample t test with SPSS 10.0 software package. RESULTS: The agar diffusion essay showed that A.actinomycetemcomitans had no effect on the growth of S.mutans, L.acidophilus A.naeslundii and A.viscosus. While these 4 kinds of cariogenic bacteria could inhibit the growth of A.actinomycetemcomitans. The ratio of A.actinomycetemcomitans in the dual-species suspension decreased gradually.In dual-species BHI broth, the proportion of A.actinomycetemcomitans cultured alone ahead of 12 hours decreased as well, which came to 0 at 24-hour in S.mutans and L.acidophilus groups. There was significant difference between different time groups(P<0.05).The single A.actinomycetemcomitans was failed to form three-dimensional biofilm and just a small quantity of cells accumulated and adhered. On the contrary, the 4 kinds of single cariogenic bacteria could form mature biofilms respectively by themselves at 48-hour,of which the appearance of biofilms had no apparent change to that of single cariogenic bacteria after mixing A.actinomycetemcomitans. CFU of dual-species biofilms indicated that the percentage of A.actinomycetemcomitans in biofilms decreased gradually by changing medium per 12 hours. There were significant difference among the three time spots(P<0.05). CONCLUSION: The study shows that S.mutans, L.acidophilus A.naeslundii and A.viscosus could inhibit the growth of A.actinomycetemcomitans in vitro.

[Effect of A.viscosus on growth of P. gingivalis in vitro].

PURPOSE: To investigate the effect of A. viscosus on growth of P. gingivalis in vitro. METHODS: Groups as single-species(A.viscosus or P.gingivalis) and dual-species (A.viscosus and P.gingivalis) were incubated in BHI broth anaerobically at 37 degrees C, and growth curve of each group was monitored for 48 hours; Meanwhile the dual-species cultures of 2-hour interval were taken and the dilution was inoculated on BHI blood agar plates for 72 hours. The percentage of P. gingivalis was detected. BHI blood agar plates inoculated with P. gingivalis were prepared, and different concentrations of A. viscosus and its degerming supernatant were inoculated on the above plates in dropping method and incubated anaerobically for 72 hours. Zones of inhibition were measured and the data were analysed with SPSS 10.0 software package for one-way ANOVA. RESULTS: A. viscosus was in logarithmic phase of growth at 2-hour and reached plateau at 8-hour. P. gingivalis entered logarithmic phase at 12-hour and reached plateau at 32-hour. Co-culture group was in logarithmic phase of growth at 2-hour and reached plateau at 12-hour. The percentage of P.gingivalis decreased gradually on BHI plates (P<0.05) and at 8-hour no P. gingivalis colony was found. The average diameters (mm) of inhibition zones were 19.3, 17.4, 13.2, 9.8 when the concentration of A. viscosus applied was 1 x 10(9), 10(8), 10(7), 10(6) CFU/ml, respectively. There was significance difference among the four groups (P<0.05). The supernatant of A. viscosus didn't show restrain on plates with P. gingivalis. CONCLUSION: The study suggests that A. viscosus could inhibit the growth of P. gingivalis by nutrition competition in vitro.