Objective To examine the effect of oral external suction on environmental pollution of microorganism in dental clinic.Methods Aerobe was counted na observation index of air contamination and air sample of the area leveal 1m and 2.5 m,hight 1m,which using oral cavity collectors of aspirator or not was collected by the method of sedimentation.Results The datum of the group with oral cavity collectors of aspirator was much lower than the group without it.Conclusion Environmental pollution from tooth treatment in dental clinic can be reduced by using oral extemal suction.

Objective:To compare the caries experience and the kinds of dental treatment between children with autism spectrum disorders (ASD) and children without systemic disease who were all treated under general anesthesia.Methods:Totally 103 children with ASD who received dental treatments under general anesthesia in 13 professional dental hospitals around China from April to November 2016 were included in the present study. A group of 97 children without systemic disease, according to the age, gender and application propensity score matching method, were chosen as controls, who received dental treatments under general anesthesia between January 2015 to November 2018 in the same hospitals as the children with ASD. Decay missing filling tooth (DMFT/dmft, DMFT for permanent teeth and dmft for primary teeth) indices of two groups of children and the contents of the dental treatments under general anesthesia were analyzed.Results:No significant difference of DMFT/dmft index ［ M( Q25, Q75)］ was found between children with ASD group ［0 (0, 3)/11(8, 14)］ and control group ［0 (0, 3)/9(7, 13)］ ( P>0.05). The average number of dental treatments under general anesthesia and the average number of endodontic treatment in children with ASD were 13 (11, 15) and 3 (2, 6) teeth respectively, while those in the control group were 12 (9, 14) and 2 (1, 4) teeth respectively, the differences were statistically significant ( P<0.01, P<0.05). Conclusions:No significant difference was found between children with ASD and the normal controls who receive dental treatments under general anesthesia in DMFT/dmft index, but the treatment needs of children with ASD is relatively higher, and their tooth decay is relatively severer.