The purpose of this paper is to present the rationale for registration of the Seated Condylar Position (SCP)/Centric Relation (CR) position of the condyles.
The purpose of this paper is to present the technique for registration of the Seated Condylar Position (SCP)/Centric Relation (CR) position of the condyles: a two-piece wax bite registration with deprogramming and no ...The purpose of this paper is to present the technique for registration of the Seated Condylar Position (SCP)/Centric Relation (CR) position of the condyles: a two-piece wax bite registration with deprogramming and no mandibular manipulation.展开更多
A new type of amphiphilic derivative of carboxymethylchitosan(CMCHS) was prepared by reaction of CMCHS with p-nonylphenyl glycidyl ether. The structure of the resulting derivatives, i.e., (2-hydroxyl-3-p-nonylphenoxy)...A new type of amphiphilic derivative of carboxymethylchitosan(CMCHS) was prepared by reaction of CMCHS with p-nonylphenyl glycidyl ether. The structure of the resulting derivatives, i.e., (2-hydroxyl-3-p-nonylphenoxy) propyl-carboxy-methylchitosan(HNP-CMCHS) had been identified by UV and IR spectroscopy. They are water-soluble and have surface activity, which is related to the degree of substitution and the added electrolyte in the solution. In the presence of NaCl, two transitions appeared on the surface tension-concentration plots, that means the possibility of the formation of intramolecular micelle. It was also found that it need a long time for the surface tension of the derivative solutions to get a equilibrium value and the time is related to the derivative concentration, degree of substitution and added electrolyte of the solution.展开更多
The cytotoxicity profile of three chitosan derivatives with different affinity to water was evaluated in vitro. The derivatives selected were carboxymethylated-chitosan (CMCH), linoleic acid modifiedchitosan (LACH...The cytotoxicity profile of three chitosan derivatives with different affinity to water was evaluated in vitro. The derivatives selected were carboxymethylated-chitosan (CMCH), linoleic acid modifiedchitosan (LACH) and deoxycholic acid modified-chitosan (DACH), respectively, and the results of FTIR and NMR confirmed the successful modification. Cytotoxicity of these polymers was investigated via the red blood cell lysis assay and the MTT assay. The red blood cell lysis test showed that CH elicited a certain level of red blood cell toxicity, while CMCH, LACH and DACH all displayed low membrane damaging effects, with the hemolysis rates of 2.385%, 1.560% and 4.404%, respectively, which comes well within permissible limit (5%). The MTT assay revealed that CH exhibited significant inhibitory effect on fibroblast proliferation at higher concentration, while its three derivatives showed no cytotoxicity. CMCH had stimulatory effects on fetal mouse fibroblast proliferation. Differences in cytotoxicity of CH and its derivatives may result from the specific chemical modifications leading to the alteration of molecular charge density and type of the cationic functionalities, structure and sequence, and conformational flexibility.展开更多
Poly (N-isopropylacrylamide) (PNIPAAm)/carboxymethylated chitosan (CMCH) hydrogels were prepared by irradiating the aqueous solution mixture of NIPAAm and CMCH by 60 Co γ-ray.The effects of feed ratio of NIPAAm...Poly (N-isopropylacrylamide) (PNIPAAm)/carboxymethylated chitosan (CMCH) hydrogels were prepared by irradiating the aqueous solution mixture of NIPAAm and CMCH by 60 Co γ-ray.The effects of feed ratio of NIPAAm and CMCH,temperature,pH and ionic strength on the swelling ratio of PNIPAAm/CMCH hydrogels were studied.The results show that the addition of CMCH shifts the lower critical solution temperature (LCST) of the PNIPAAm hydrogel to higher temperature.The PNIPAAm/CMCH hydrogel displays not only pH-and thermo-sensitivity,but also ion-sensitivity.Differential scanning calorimetry (DSC) was applied for the determination of the LCST of the hydrogel.展开更多
The purpose of this paper is to conduct an extensive review of the literature on the relationship between occlusion and occlusal factors and TM dysfunction. This paper attempts to explore why the link between occlusal...The purpose of this paper is to conduct an extensive review of the literature on the relationship between occlusion and occlusal factors and TM dysfunction. This paper attempts to explore why the link between occlusal factors, which have historically been implicated in producing TMD, and dysfunction has not been clearly evident from the dental literature.展开更多
文摘The purpose of this paper is to present the rationale for registration of the Seated Condylar Position (SCP)/Centric Relation (CR) position of the condyles.
文摘The purpose of this paper is to present the technique for registration of the Seated Condylar Position (SCP)/Centric Relation (CR) position of the condyles: a two-piece wax bite registration with deprogramming and no mandibular manipulation.
文摘A new type of amphiphilic derivative of carboxymethylchitosan(CMCHS) was prepared by reaction of CMCHS with p-nonylphenyl glycidyl ether. The structure of the resulting derivatives, i.e., (2-hydroxyl-3-p-nonylphenoxy) propyl-carboxy-methylchitosan(HNP-CMCHS) had been identified by UV and IR spectroscopy. They are water-soluble and have surface activity, which is related to the degree of substitution and the added electrolyte in the solution. In the presence of NaCl, two transitions appeared on the surface tension-concentration plots, that means the possibility of the formation of intramolecular micelle. It was also found that it need a long time for the surface tension of the derivative solutions to get a equilibrium value and the time is related to the derivative concentration, degree of substitution and added electrolyte of the solution.
基金the National Natural Science Foundation of China(No.30370344)
文摘The cytotoxicity profile of three chitosan derivatives with different affinity to water was evaluated in vitro. The derivatives selected were carboxymethylated-chitosan (CMCH), linoleic acid modifiedchitosan (LACH) and deoxycholic acid modified-chitosan (DACH), respectively, and the results of FTIR and NMR confirmed the successful modification. Cytotoxicity of these polymers was investigated via the red blood cell lysis assay and the MTT assay. The red blood cell lysis test showed that CH elicited a certain level of red blood cell toxicity, while CMCH, LACH and DACH all displayed low membrane damaging effects, with the hemolysis rates of 2.385%, 1.560% and 4.404%, respectively, which comes well within permissible limit (5%). The MTT assay revealed that CH exhibited significant inhibitory effect on fibroblast proliferation at higher concentration, while its three derivatives showed no cytotoxicity. CMCH had stimulatory effects on fetal mouse fibroblast proliferation. Differences in cytotoxicity of CH and its derivatives may result from the specific chemical modifications leading to the alteration of molecular charge density and type of the cationic functionalities, structure and sequence, and conformational flexibility.
基金supported by the Shanghai Nano-material Project Foundation (Grant No.0452NM024)the Shanghai Leading Academic Discipline Project (Grant No.T0105)
文摘Poly (N-isopropylacrylamide) (PNIPAAm)/carboxymethylated chitosan (CMCH) hydrogels were prepared by irradiating the aqueous solution mixture of NIPAAm and CMCH by 60 Co γ-ray.The effects of feed ratio of NIPAAm and CMCH,temperature,pH and ionic strength on the swelling ratio of PNIPAAm/CMCH hydrogels were studied.The results show that the addition of CMCH shifts the lower critical solution temperature (LCST) of the PNIPAAm hydrogel to higher temperature.The PNIPAAm/CMCH hydrogel displays not only pH-and thermo-sensitivity,but also ion-sensitivity.Differential scanning calorimetry (DSC) was applied for the determination of the LCST of the hydrogel.
文摘The purpose of this paper is to conduct an extensive review of the literature on the relationship between occlusion and occlusal factors and TM dysfunction. This paper attempts to explore why the link between occlusal factors, which have historically been implicated in producing TMD, and dysfunction has not been clearly evident from the dental literature.