Research On Histocompatibility And Controllability Of The SR/PVPP Composite Expand Implant Used For Lengthening The Short Nose

BackgroundLengthening the short nose is arguably the most difficult operation in aesthetic rhinoplasty.There are so many techniques to treatment the different characteries such as an obtuse columellarlabial angle,an overprojecting tip and a shallow slope of the dorsum.Of course the length of the nose is short.But all of these methods always accompany with some complications:needing several times operations,lefting more scar on the nose and the recipient site ischemia after getting much more grafts from donor site.We can lengthening the nose frame no limited with different implants, but the nose soft tissue covering is shortage! So we can not reach to our ideal desire for lengthening the nose. More and more cosmetic requirements have made us to look for the useful ways for lengthening the nose.We can use the autos cartilages or bone grafts,or artificial implants to make the nose longer,but so many papers reported the complication about the nose tip broken after putting over long implants in the nose.We should avoid this serious complication with sufficient estimate for the nose soft tissue covering enough when we lenghtening the nose.So it is the key point in our treatment for the short nose to get enough covering,not only the frame.The best way to get the epactal skin coveting is the soft tissue expandsion.But is is so difficuty to bury the expander in the nose because of it complex construction and with the important breath function.It is not easy to accept the way even we use the expander in the nose with injection water continue and twice operations trouble.Another problem for use the expander in the nose is the nose shape is so individual.So there is not any formal report about using expander on the nose.How to solve the problem that we face the nose soft tissue covering insufficient?We imagine an idea creating the automatic expanding implant just like the soft tissue expander in the nose.We can make the desige the implant size,shape and the expand direction and time(speed) according the patient and the doctor requirments. We use this kind of automic expand implant can make more soft tissue coveting for lengthening the nose frame at the same time. The silicone nose implant is the most common to use for lengthening the short nose.It is the idea implant material received in the world.But it is not of the expand ability.The hydrogel is the polymers with hydrophilicity.It can expand to be much times size in water but not dissolve in water.It can also inoculate to some material with better mechanical property.Both of them can just meet our requirement for the automatic expanding implant.It can fill the vacuilty in rhinoplasty implant research in the world.Reasearch Purpose1.To study the nose frame anatomy through the dissection for the different aparts in nose hard structure to find the foundation for lengthening nose.To look for the useful method to observe the nasal cartilage without operation.2.Use the silicone and the hydrogel to creat a new composite automatic expanding implant with both of expand and support features.To make this implant to be controlled the size and the direction by different PVPP rate and the hard silicone as prohibit the expand direction we do not want.3.To study the expand property through the electron microscope observe the structure inside SR/PVPP automatic composite implant.4.To study the different expand property and histocompatibility between the SR/PVPP automatic composite implant and pure silicone implant in the same rabbit back using 6 different PVPP rate from 0%to 35%.5.To study the effective expanding in the rabbit nose tip through observe the skin stroma cell mitochysis and the local blood variations.6.To look for the useful way to observe the automatic expand SR/PVPP implant change in the body.Material and Methods1.Lenghtening short nose basic anatomy researchWe dissect the nasal strcture on the surfacial 2 fixation cadavers and 6 fresh cadavers.We measure the separating distance between the upper lateral cartilage and the lower lateral cartilage after dissecting their connection lefting integrated the mucosa when we pull the nose tip with 300g force.We chose the 3 points to measure, the middle and both sides.Except the cadaver disscttion,we use the US CE co.ltd CT to scan the nose in 5mm and use the HP workstation XW8000 workstation to reconstruction nasal soft surface frame.2.SR/PVPP controllability automatic expand implant synthesis and exosyndromeWe mix the medical methylvinylsilicone and PVPP in the special machine,let the mixing material stay in room temperature 24hours.Then we put it in another machine under 160℃/3MPa 15min.At last we put it into dry blast machine under 180℃for 4 hours.After those procedures,we get the SR/PVPP composite implant.We test the implant properties including the countenances,the hydrophilicity and the hydrating expanding.3.3.We use the Hitachi S-3000 type electron microscope to observe the different structure between the SR/PVPP composite implant and the pure SR implant.We observe the changes for the SR/PVPP composite implantswith different PVPP rate after expanding in saline in the dry condition.We measure the implants length and volume.To study the SR/PVPP composite implant internal structure,observe the recovery test for this implant and test the controlled direction expanding.We use the gradient compound technique to make the silicone and the SR/PVPP composite implant to be the lateralization expanding implant.4.To observe the body responses to the different PVPP rate SR/PVPP composite implants in the rabbit body.We put 36 cakes SR/PVPP composite implants with 6 different PVPP rate into the different site on the rabbit back according the Latin square statistical design.We buried 6 different PVPP rate composite implants in the same rabbit back.We measured the lenghter of the rabbit nose with the new implant everyday.We analysis the result after 60days we put in the implant.5.We divide 14 rabbits to three groups(SR/PVPP composite implant group,SR implant group and no implant group).We use ES-1000type Doppler to test the nose tip skin blood flow rate and the peak value。Then we random chose a rabbit to get the nose tip skin sample to do the HE hitological section 3,7,9,14,30,60,90days after inset the implant into the nose tip.We use the microscope to get the pictures in high power lens and count the cell mitochysis number in the skin stroma continuously in the different day after input the implant..6.We use Siemens Magneton Impact Expert 1.5T MRI to test the different implant in the different animal groups(cats and rabbits).We check the cats or rabbits nose tip with or without implant 3,7,10,16,35days after putting the implant into the nose tip continuously.All the animals are all under general anaesthesia.Result:1.Through the dissection for the different aparts in nose hard structure we found the connection between the ULC and theLLC is the foundation for lengthening nose. The largest separating distance in the middle is 7.04 mm,average 5.98 mm and,the The largest separating distance in the side is 5.03mm,average 3.92mm between the ULC and the LLC after dissecting their connection lefting integrated mucosa with 300g pull force.The CT to scan the nose and the HP workstation XW8000 workstation are the useful method to observe the nasal cartilage without operation.2.According the researches for silicone reshaping and the medical hydrogel application before,we use the silicone as the basal body to composite with the PVPP (as the water absorb component) to create new automatic expand composite implants. Contact angle results indicated that after the introduction of PVPP hydrogel,the surface hydrophilic properties of silicone rubber material were significantly improved. The water swelling properties and mechanical properties were also investigated.And it was found that,with the increasing of PVPP content,composites' volume swelling ratio increased while mechanical properties decreased.And the equilibrated volume swelling ratio in physiological saline was similar with deionized water.3.After studying the SR/PVPP composite implant internal structure,we found that the PVPP is the reason for SR/PVPP composite implant expanding when it meet water.We found that the SR/PVPP composite implants with different PVPP rate can be recover to original size and shape after expanding in saline in the dry condition.Using the gradient compound technique we creaded the silicone and the SR/PVPP composite implant to be the lateralization expanding implant.4.We put 36 cakes SR/PVPP composite implants with 6 different PVPP rate into the different site on the rabbit back according the Latin square statistical design.We found that the SR/PVPP composite implants can expand notably.There is a significant deviation between the SR/PVPP composite implant and the SR implant.The experiment result showed us the optimization PVPP rate is 25%.From our test,we have discovered that PVPP-silicone composite expand implant has better histocompatibility than the pure silicone implant. 5.We put the 25%SR/PVPP composite implant t the nose tip in 9 rabbits.At same time,we put the pure silicone implants in another rabbits nose tip.We made the control study among the 25%SR/PVPP composite implant,silicone implant and not any implant(blank).We found that the 25%SR/PVPP composite implant can expand the local skin soft tissue effectively through the study the nose tip skin blood flow and the skin epicyte karyokinetic division.6.We also use the MRI in dynamic state to observe the SR/PVPP composite implant in the cats and rabbits body.The result has proved that the SR/PVPP composite implant could expand the soft tissue and to be the implant in the nose.Conclution:1.Through the dissection for the different aparts in nose hard structure we found the connection between the ULC and theLLC is the foundation for lengthening nose.2.After the SR and PVPP mixed with the physical way,the surface hydrophilic properties of silicone rubber material were significantly improved.With different PVPP rate the increasing of PVPP content,composites' volume swelling ratio increased.And the equilibrated volume swelling ratio in physiological saline was similar with deionized water.Using the gradient compound technique we treaded the silicone and the SR/PVPP composite implant to be the lateralization expanding implant.The SR/PVPP composite implants can expand notably.There is a significant deviation between the SR/PVPP composite implant and the SR implant. 3.The SR/PVPP composite implant can expand the local skin soft tissue effectively through increasing the nose tip skin blood flow and the skin epicyte karyokinetic division.The SR/PVPP composite implant not only is the common implant for nose frame,but also is the expander in the nose to make more skin for nose tip.4.The CT to scan the nose and the soft tissue reconstruction technique are the useful method to observe the nasal cartilage without operation.MRI can be used to observe the PVPP-silicone composite implant in the bodye in dynamic,continously and no-invision.It is the useful tool to test the SR/PVPP expand implant in human body as we requirement...