Duct Cast Technology Research And Application

BackgroundThe duct cast technology is an anatomy specimen manufacture skill, in the cast fundamental research, the modelling design and the technical operation aspect, has its originality. In order to study the lumen internal organs, specially the vascular system complex three-dimensional construction, inject into some material toward the lumen, after material hardening, corrode and eliminates the organize, only leave behind the filling material the method to be called the cast specimen manufacture method. It includs the cast auxiliaries choice, the injecting equipment preparation, the material choice and processing, the intubation and the injection, the corrosion and the flushing.and the later period processing.In the cast auxiliaries choice, at present the solvent volatility coagulates the formation method and the chemical reaction formation method can be used in anatomy technology the formation method,in the solvent volatility coagulates the formation method, had thought the crosses the chloroethylene is the quite ideal cast material, and is casts the specimen first choice auxiliaries. The merit is:The support strength strong, the flexibility good, the formation artistic, the price inexpensive, easy to purchase, chemistry performance and the physical performance quite is all stable. But also has the shortcoming:①After injected for the first time,specimen must be injected for 4～5 times afterwards,which may cause the specimen filling and beautiful, but it brings certain trouble to the injection;②The support strength compares self-curing resin denture to be weak, the cast specimen easy to distort in the corrosion and the conditioning process, which causes the specimen to distort. In the chemical reaction formation method, self-curing resin denture is applies widely, its merit is one-time molding, no adding perfusion, specimen filling, bright color and clean. Its shortcoming is:①The polyreaction is fierce,which produces quantity of heat,and causes the specimen to appears the cavity;②The coagulation time is too short, which make the operates not be easy. Therefore, must study one kind of new auxiliaries to improve the cast specimen quality.The manufacture retentions the skeleton the blood vessel cast specimen, usually has the alkali etch method, the natural etch method, the calcium sulfate saturated etch method, the commonly used corrosive are the sodium hydroxide, the potassium hydroxide or the sodium hypochlorite in the alkali etch method. Its basic principle is responded through the lye and the organization, which eliminates the organization, responds quickly, but its shortcoming is that the specimen easy to have the saponified phenomenon, easy to damage the osseous structure, which creates the specimen to be incomplete, not artistic. Therefore, must study one kind of improvement the corrosive liquid to satisfy enhances the retention skeleton cast specimen quality.This experiment is to study the best preparation proportions of mixed-filler in different proportions of chloroethylene and self-curing resin denture; Puts in first the specimen in the 5%～10%hydrogen peroxide solution 1-2 days, then puts in again joins in the potassium hydroxide improvement cast corrosive liquid which the right amount ethyl alcohol and the calcium hydroxide compound, obtains the improvement the cast etch method; Using mixed-filler of chloroethylene and self-curing resin denture to manufacture masculine uninary system complete picture cast specimen and the feminine arteria uterina cast specimen, and then observ specimen effect; Using the improvement cast etch method, to manufactures the retention bone head pate arteriovenous cast specimen, and observ etch method effect.In summary, this topic for inquired about one kind of new cast auxiliaries and the improvement retention skeleton cast etch method carries on experimental study.ObjectiveTo study the best preparation proportions of mixed-filler in different proportions of chloroethylene and self-curing resin denture; to modify nowadays mold etching solution. And the modified corrosion casting method and technological achievements would be used in the production of duct casting specimens.Method1. In different proportions according to the preparation of self-curing denture acrylic and liquid denture acrylic, the reaction of mixture of conditions and the stiffness of the material were observe after solidification. According to them, the optimum proporations of the scope of the preparation were got. After these materials were prepared in different proportions over 20%of vinyl chloride and the self-curing denture materials, the mobility of the mixture, reaction time, the stiffness of the material after solidification, and flexibility were observed. According to the mobility of the mixture, the stiffness and flexibility after solidification, the optimum formulations were obtained.2. It is commonly used for potassium hydroxide or sodium hydroxide in caustic alkali. First,5%～10%hydrogen peroxide solution was prepared, and then 7.13 mol/L potassium hydroxide was prepared, that is to say,40 grams of potassium hydroxide dissolved in 100 grams of water. The solutions were cooled to room temperature. Alkaline etching solutions were prepared with lye and ethanol in different proportions. Then calcium hydroxide was added into the solutions to prepare of saturated concentration of calcium hydroxide, which was 0.0224 mol/L. And then the best formula was determined according to the corrosion of specimens.3. The prepared mixed-filler with vinyl chloride and the self-curing denture materials were prepared to produce male urinary system picture mold cast specimens and female specimens of uterine artery using the method of multi-point intubation and perfusion. And then the effects of specimen were observed. Head and neck arteriovenous cast specimens were manufacture by improving mold etching methodology. And also the effects of etching method were observed.Results1. New fillers configurationsThe optimum proportion of the mixing filler with chloroethylene and self-curing resin denture was that self-curing denture acrylic:20%perchloroethylene:liquid denture acrylic=0.5～0.8:0.4-0.6:1. After research, the new type of filler was successfully prepared.2. Modification of corrosion cast methodOptimum concentration of hydrogen peroxide ranged from 5%to 10%; the best ratio of 7.13 mol/L Potassium hydroxide lye and Ethanol ranged from 1:0.1 to 0.2. And then 0.166 g/100g calcium hydroxide was added into solutions to successfully prepare the modified alkali corrosion of saturated calcium hydroxide.3. Application of research achievementsCast specimens of male urinary system was successfully manufactured by filling new mixed-filler which research above. The specimen can clearly display the several structures of urinary system, such as renal pelvis, ureter, urinary bladder and urethra, and so on. These structures was with the merits of bright color, proper appearance, easily distinguish, which comprehensively and intuitively display the whole view of male urinary system. The specimen also demonstrated unilateral vas deferens, bilateral seminal vesicle and part of prostate tube. The new multi-point filler perfusion uterine artery, which is used to produce a cast specimens with bright colors, duct filling, shape beauty, which comprehensive and intuitive displayed of the uterine blood system. The new fillers and modified alkali corrosion method were applied to produce a bone window of the head and neck arteriovenous cast specimens with the merits of significant levels of artery and vein, no blood vessel subsidence to stick to skull, and no bone structure destroyed, which clearly displayed the structure of intracranial and extracranial arteriovenous.Conclusion1. This study showed the best preparation ratio of the scope of mixed-filler chloroethylene and self-curing resin denture was that self-curing denture acrylic:20% perchloroethylene:liquid denture acrylic=0.5～0.8:0.4～0.6:1. Mixed-filler will not emerge excessive gas because of intense polymerization reaction, and cast speciman is with the merits of the beautiful shape, blood vessels filling, bright color and clean, proper density, which have the both advantages of vinyl chloride and denture materials which can compensate for the shortcomings of the previous materials which could result the cast specimens collapse, poor appearance, and shape distortion. These fillers have the toughness and brightly colored feature as vinyl chloride features and also have the features of strong support strength and full appearance as denture materials. And also have the merits of one-time molding, no adding perfusion which can save time for the production of cast specimens. After several experiments, the formula is more reasonable than the ideal filler。2. Specimen manufactured by modified cast etch method can achieve better results. Firstly, specimens should be placed in 5%-10%hydrogen peroxide solutions with higher oxidative ability and oxidized, which accelerated significantly the corrosion rate for specimen; Modified ethyl alcohol alkali corrosive liquid with the strong and fast corrosive effect. And the time of the specimen manufacturing is only 12-14 hour which can reduce the damage to the bone for etching solution obviously and can preserve integrated bone. Controlling the concentration of etching solution, etching time and corroded areas, it can effectively corrode fat to avoid the production of fat saponification; with more complete preserved articular capsule, ligaments and other soft tissue structures. Thus the specimen is perfect form and bright-color.3. The new mixed-filler can be successfully used in any duct. The cast specimens of male urinary system and female uterine artery can be produce. This technology can produce these types of specimens which cannot be display previous; and modified alkali etching method can be applied to all of the bone-cast specimens.