In vivo imaging of Ca2+ accumulation during cotton fiber initiation using fluorescent indicator YC3.60.

KEY MESSAGE: Non-tip-focused Ca 2+ gradient indicated by genetically expressing a FRET-based calcium sensor YC3.60 was established in spherical expanding cotton fibers, which is vital for cotton fiber initiation. Cotton fiber is a single cell elongated from ovule epidermis. It is not only the most important natural fiber used in the textile industry but also an ideal model for studying cell differentiation and elongation. Before linear cell growth, cotton fibers undergo spherical expansion at the beginning of initiation. Ca2+, as an important secondary messenger, plays a central role in polarized cell growth including cotton fiber elongation. However, the role of Ca2+ in fiber initiation is far from well understood. In this paper, through ovule culture we demonstrate that Ca2+ is crucial for fiber initiation. Using transgenic cotton expressing the fluorescent Ca2+ indicator YC3.60, we show cellular and intracellular distribution of Ca2+ in cotton ovule epidermis and fiber cells. In the initiating fiber cell, Ca2+ accumulated mainly at the base of the cell, while in the fast elongating cell, the Ca2+ was enriched in the tip region. This cellular distribution of Ca2+ reported by YC3.60 was confirmed by the staining with a Ca2+-sensitive dye fluo-3/AM. Compared to the fluorescent dye staining, the YC3.60 system can reveal more detailed information on the intracellular distribution without photobleaching. Taken together, our data suggest that Ca2+ plays an important role in spherical expansion of cotton fiber initials.

[Application of orthodontic fixed device in restoring teeth space in children].

PURPOSE: To assess the effect of orthodontic fixed device in restoring teeth space in children. METHODS: Brackets with archwire and open coil spring were used to restore teeth space loss in 8 cases. RESULTS: In all 8 cases, 6 cases achieved success, 1 case had improvement and 1 case had failure. Within these cases, the fastest restoring time was 2 months and the slowest restoring time was 7 months. CONCLUSIONS: It is an ideal method to restore teeth space with orthodontic fixed device. It is a simple, fast and economic for early orthodontic treatment. Due to the fewer cases, further study is needed.

[Clinical evaluation of pit and fissure sealant with light-cured flowable resin and light-cured pit and fissure sealants].

PURPOSE: To evaluate the difference between light-cured flowable resin and light-cured pit and fissure sealant in the cost and retention rate of pit and fissure sealant treatment. METHODS: Two hundred and fifty six children aged from 7 to 10 years were selected in this study. Each of them had at least two caries-free first molars. One first molar was sealed with light-cured flowable resin and the other one was sealed with traditional light-cured sealant. The portable dental chair were used to absorb saliva and cotton rolls were applied for moisture control. The operation time and number of cotton rolls used were recorded. After one year, the reservation of material was checked by two dentists using explorer. All the procedures were undertaken in schools.The data were analyzed using SPSS10.0 software package. RESULTS: It took 3.53 minutes for one tooth to be sealed with traditional light-cured sealant and 3.32 minutes with light-cured flowable resin (P<0.05). The retention rate of the light-cured flowable resin group was significantly higher compared with traditional light-cured sealant group (P<0.05). CONCLUSION: Light-cured flowable resin can be used as fissure sealant to prevent caries in a shorter operation time used in schools.

[Application of cone-beam computed tomography in the treatment of impacted maxillary teeth].

PURPOSE: To investigate the treatment of impacted maxillary teeth with localization via cone-beam computed tomography (CBCT). METHODS: Eleven cases with impacted maxillary teeth on X-ray examination were selected from 2009 to 2010. The impacted maxillary teeth were scanned by CBCT.The three-dimensional images of impacted maxillary teeth were obtained by multiplanar reconstructions (MPR) to determine the location of impacted teeth. RESULTS: CBCT and MPR can demonstrate the morphology and location and growing state of the impacted maxillary teeth. CONCLUSION: CBCT and MPR are the most accurate and effective methods to localize the impacted maxillary teeth.

[An investigation of the clinical effect of the 0.3% Triclosan varnish on caries prevention of primary teeth].

PURPOSE: To assess the clinical effect of the 0.3% Triclosan varnish on caries prevention. METHODS: Six hundreds and six children aged 2 to 5 years old, who came from 4 different kindergartens, took part in this study. Two kindergartens were chosen randomly as the experimental group, and the other two kindergartens as the control group. The mean dmft of two groups were recorded. The Triclosan varnish groups used the 0.3% Triclosan varnish and were spreaded the varnish every half year, twice a year. After one year, the mean dmfs of the two groups were examined again. The SPSS 9.0 software package was used. RESULTS: The mean dmfs of the two groups had no significant difference for data analysis(P>0.05). After one year, the increment of the mean dmfs had significant difference between the experimental and the control groups(P<0.05). CONCLUSION: 0.3% Triclosan varnish can prevent primary teeth from caries effectively.

[Clinical effect of Sonicare electric toothbrush in treating gingivitis].

OBJECTIVE: To observe the clinical effect of Sonicare toothbrush in treating gingivitis by means of using Sonicare toothbrush in both healthy group and gingivitis group. METHODS: 50 medical students aged 18 to 25 years old were selected. At first,The gingival Index(GI) was examined and they were divided into 2 different groups. The students were instructed to use the Sonicare toothbrush, demanding them to brush teeth 2 times one day and 2 minutes each time. One month later,the GI were reexamined. RESULTS: After one-month period of using Sonicare toothbrush, the GI decreased significantly in both groups and the difference was statistically significant. CONCLUSION: Sonicare toothbrush can remove debris and improve gingival health. It is effective tool for family oral care.

[The cost-effectiveness of ART and resin sealant on caries prevention].

OBJECTIVE: Pit and fissure sealants have been widely used to caries prevention. More often, ART is used in caries treatment. ART was used to prevent caries in recent years. However,the cost-effectiveness of ART that is used to caries prevention still remains unclear. The aim of the present research was to compare the cost-effectiveness of ART with that of resin sealant in caries prevention for primary school children. METHODS: Two hundred and twelve children aged 7 to 9 years old took part in this research. The molar of every child on one side of the mouth was sealed by light-cure resin sealant(Concise,3M) and by chemically firmed glass ionomer (Ketac-molar, ESPE) on the opposite side. The routine methods were used to seal teeth and the cotton rolls and suction were used to keep dry. The time for manipulation,amount of materials and times for repetition in the program were recorded. The retained rate of sealed material on the teeth was checked month after treatment. RESULTS: The results indicated the time for manipulation,cotton rolls and times for repetition in sealant was respectively 3.54 (min.), 2.52 and 0.04 (times) in sealant and 3.18 (min.),1.13 and 0.03 (times) in ART. The material of ART was more expensive than of resin sealant. Respectively,the costs of glass ionomer and resin sealant were 3.77 and 0.93(Yuan). However, the cost of equipment used in sealant were much more expensive than that used in ART. Furthermore, there was no significantly difference between sealant and ART in the remaining rate. CONCLUSION: The results suggest that ART is more cost-effective than sealant on caries prevention.