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Objective To analyze the influence of a dental caries phototherapy device using neodymium-yttrium-aluminum-garnet (Nd:YAG) laser on the temperature of tooth pulp chamber of different sites and morphologies under different irradiation duration and power. Methods Fifty intact isolated teeth were collected and randomly divided into middle incisor group, upper right first premolar group, upper right second molar group, upper left first premolar group, and upper left second molar group. Each experimental group was irradiated according to the laser power 1.5, 1.6, 1.7, 1.8, 1.9 and 2.0 W, and the irradiation duration 30, 60, 90 s. The temperature rise of the pulp chamber was recorded with a thermocouple thermometer. Results After the laser irradiation, the temperature of the tooth pulp chamber increased, and the temperature rise was less than 5.5℃, i.e. the threshold leading to the dental pulp necrosis. Conclusions The use of laser to prevent dental caries will increase the temperature of the tooth pulp chamber, but the temperature rise in the range of 5.5 ° C is relatively safe and will not cause irreversible damage to the pulp tissue.
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Objective To study the application of photodynamic therapy (PDT) for dental caries prevention using whole body luminescence fiber,and to investigate the effects of PDT on the content of Ca and P in rat molar enamel.Method The rat dental caries model was established by inoculating with S.mutans.Eighty male rats were randomly divided into five groups,including three experimental groups:17 mW (8 mW/cm2) PDT (group A),34 mW (15 mW/cm2) PDT (group B),68 mW (30 mW/cm2) PDT (group C),a positive control group:20 g/L NaF solution (group D),and a negative control group:0.9％ physiological saline (group E).The experimental groups were treated by 40 μg/mL hematoporphyrin monomethyl ether (HMME) and 650 nm diode laser irradiation.The experiments were conducted for 4 weeks.The contents of Ca and P in the molars of each group were measured by inductively coupled plasma emission spectrometry.Results The contents of Ca and P in group B,C and D after PDT were significantly higher than those in group A and E (all P＜0.05).The contents of Ca and P in group A showed no significant difference before and after PDT,while those in groups B and C showed significant increase after PDT (all P＜O.05).The increment of Ca in group A after PDT was lower than that in group D (P＜0.05),while those in group B and C were significantly higher than those in group D (all P＜0.05).There was no significant difference in the increment of Ca and P between group B and C after PDT.Conclusions In the range of the experimental parameters,the PDT promoted effect of tooth remineralization is better than 20 g/L NaF.The levels of Ca and P in the tooth enamel can be promoted by PDT treatment,and the contents of Ca and P are related to the pewer of PDT.The effect of low power PDT on the remineralization of enamel is not obvious.The contents of Ca and P in the tooth enamel are increased with laser power of PDT.When the laser power increased to a certain value,the change in contents of the two elements is not obvious.PDT can maintain the tooth remineralization microenvironment.
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Objective To preliminarily select safe parameters for different forms of teeth by irradiating 532 nm picosecond Nd∶YAG laser on human isolated teeth with different irradiation time length and power.Methods Isolated human teeth including anterior teeth,premolars,molars were irradiated with 532 nm picosecond laser.Repeated measurements were made for each tooth by thermometer to measure the temperature of pulp chamber on different time point and power,and the temperature change (△T) was calculated.Results △T of the anterior irradiation group at 0.6 W,30 s;0.8 W,20 s and 30 s;1.0 W,10 s,20s and 30s were more than 5.6 ℃,which was the same with that of premolar group at 1.0 W,30s.△T of the molar group at 1.0 W,30 s was less than 5.6 ℃.Under certain power,the temperature of pulp chamber increased with the prolonging of irradiation time (P＜0.05).At a certain time,temperature increased with the power (P＜0.05).Conclusions It is safe to carry out operation on the parameters setting of 0.8 W,10 s and 0.6 W,20 s irradiation for anteriors teeth;0.4 W,30 s,0.8W,30 s and 1.0 W,20 s for premolar teeth,and 1 W,30 s for molar teeth.In the application of 532 nm picosecond laser,attention is required to be paid on parameter setting to control input power and irradiation time.
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Objective To investigate the effects of etomidate and propofol on circulatory system and the depth of anesthesia in laparoscopic surgery of ectopic pregnancy.Methods From January 2014 to January 2015, 40 patients with ectopic pregnancy in our hospital were selected and divided into the etomidate group and propofol group according to the principle of complete random grouping.Patients in the etomidate group received etomidate induced anesthesia, and the patients in the propofol group received propofol induced anesthesia.Hemodynamic parameters and bispectral index(BIS) of two groups were evaluated at 4 time points.The incidence of postoperative nausea and vomiting, chills and bronchospasm were recored.Results There was no significant difference in heart rate (HR),systolic blood pressure (SBP) and diastolic blood pressure(DBP) between the two groups at T0,T2and T3.But at the time of induction(T1), the heart rate of patients in propofol group was significantly lower than that in etomidate group(P<0.05).While T1, compared with etomidate group, the HR and SBP significantly decreased and DBP increased in the propofol group (P<0.05), The HR and SBP at T1of patients in the propofol group and etomidate group decreased significantly and DBP increased when compared with T0(P<0.05).and etomidate group decreased significantly compared with T0 ( P <0.05 ).There were no significant differences in BIS indexes at four time points.However, BIS indexes at T1 ,T2 and T3 were significantly lower than T0 ( P <0.05 ).There was no significant difference in three kinds of complications rates in two groups.Conclusion Etomidate, compared with propofol, can better control the cardiovascular response during induction of anesthesia.Both drugs have a consistent depth of anesthesia.There is no difference in the incidence of complications.Etomidate is more suitable for patients with ectopic pregnancy laparoscopic surgery.
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Objective Nasal administration,as a common means of treatment of respiratory diseases,may normally cause bronchospasm,cough and other adverse reactions,the efficiency of nasal nebulizers has been criticized as well.This paper aims to develop a medicine atomizing device,pharmaceutically atomized in solving the existing problems,providing a modern instrument for treatment of respiratory diseases by traditional Chinese medicine.Methods The device could prepare medicine by decoction and filtration,which means this unit is divided into two functional modules,medicine preparation and herbal atomization.1 200 W heating plate is placed in decoction unit and is programmed to fit traditional decoction protocol.Steam and ultrasonic nebulised medicine are combined in atomizing unit.Another non-contact infrared heating unit also located in to control the temperature precisely.Different forms of traditional Chinese medicine and different filtration methods were selected to optimize the atomizing effect.Results An implementation of two sequence of filtration enabled optimization of atomizing.After 15 volunteers'trial,this device functioned well on Bama nasal medical protocol,and could effectively avoid the adverse reactions of the traditional way of cold fog atomizing.Conclusions The nasal nebulizer equipment on which Chinese herbal medicine treatments could directly performed,produced atomized mist particle size suitable for nasal treatment,and by generating warm steam to avoid the common clinical administration caused choking to hypoxia and other adverse reactions.Meanwhile,instrument has a friendly interactive feature to meet the clinical requirements for medicine nebulizer treatment.
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Objective The purpose of this study was to explore the efficacy of low level laser treatment (LLLT) combined with initial periodontal therapy in treating chronic periodontits.Methods Eighteen patients with chronic periodontitis were randomly treated in a spit-mouth design with combination of laser (808 nm,80 mW) treatment with scaling and root planing (experimental) or with scaling and root planing alone (contol) after OHI and supragingival cleaning.Clinical parameters of sulcus bleeding index (SBI),periodontal probing depth (PD) and clinical attachment loss (CAL) of both sides were recorded and gingival crevicular fluid samples were collected at baseline and 1,4,12 weeks after the treatment.GCF samples were analyzed for b-FGF,IL-1β,IL-8 level using ELISA assay.Results For the change of SBI and PD,only SBI in the experimental group experienced significant reduction (P＜0.05) at 1 week compared with baseline (P＜0.05),and the reduction in both groups were statistically significant (P＜0.05) at 4 weeks.The same situation occurred while both experimental groups made more significant difference (P＜0.01) at 12 weeks.The reduction of SBI was obvious in both groups when the PD was more than 6 mm.For CAL,the experimental group showed signs of improvement (P＜0.05) at 4 weeks; both groups indicated improvement (P＜0.05),while the experimental was more significant (P＜0.01) at 12 weeks.For the levels of b-FGF,it showed steady rise after treatment in experimental group,while it went up to the baseline after falling in control group.At 12 weeks,there were statistical significance of differences between two groups (P＜0.05).The changes of IL-1β and IL-8,in the experimental group showed better results than that in control group,while the difference between two groups was not significant (P＞0.05).Conclusion LLLI can accelerate the healing of periodontal tissue by reducing the SBI,decreasing the PD,improving the CAL and increasing levels of b-FGF in the GCF of the patients.
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ObjectiveTo study the feasibility of analyzing photosensitizers absorbing process by cells based on image processing technology.MethodsFluorescence images of Laryngeal cells were taken by inverted fluorescence microscope after adding photosensitizers for a certain time.Parameter L that reflects the fluorescence intensity of cells in different times was obtained and the calculation results were compared.ResultsThe fluorescence intensity of cells increased over time.Sobel operater and Otsu algorithm can both reflect the fluorescence intensity of images.ConclusionImage processing technology can effectively analyzes the process of photosensitizers absorbed by cells.
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Objective To research and design a kind of high accuracy laser power density meter to measure laser power density in clinical medicine,in order to combine laser with clinical medicine well.Methods The pyroelectric detector was used to convert the laser signal to available electrical signal,preamplifier filter circuit and control circuit were designed to match the detector,and C was used for software programming.With the combination of hardware and software design,a high precision laser power density meter was developed,which was based on AVR microcontroller.Results The instrument could measure the minimum 1 mW/cm2 of laser power density accurately and the error rate was 2％,which met the requirements of the laser power density meter parameters in medical application.Conclusion The power density meter has a high precision,small error rate and good stability,and it can measure the laser power density accurately.