Clinical And Experimental Study On Unexpected Pulp Canalization In Deep Dental Caries Treated By Laser

Unexpected pulp canalization in deep dental caries is oral cavity internal medicine common illnesses, frequently occurring disease .It is produced when getting ready for a hole or getting rid of the dirt in the cavity and the accident puts on the medulla cavity .The causes of creating this consequence have many aspects:There is variation in the dissection struture of medulla cavity;Does not pay attention to that young person,s permanent teeth and the milk teeth marrow angels are higher and the dentine is thin when eliminating the dirt in the cavities. When repairing the shape of the hole ,expending to cusps at the level of the bottom of the hole . When pulp cavity perforation happened in the past, we usually adopted the direct covering pith skill to treat. The direct covering pith skill uses medicines to cover the revealing place to preserve the vigor of the pulp.The medicine that is usually used is calvital .The pulp and the dentinoid can be seen as a physiological complex.They come from the undifferentiated mesenchyme of the tooth thelium.There are forming dentinoid cells in the pulp dentinoid complex.They lie around the pulp marching with the prodentine.The forming dentinoid cells produce dentinoid. The alkaline function of calvital is benefical to activate alkaline phosphatase that densify at the forming dentinoid cell level.It can activate alkaline phosphatase to help to form surperhard tissue.It can be used to treat cariosity,mechanical and injury pulp canalization.Its cured rate is high from observing the radiograms and clinical examinations.The pulps present chronic inflammation states observed from histology after treated with the direct covering pith skill when suffering from deep dental caries .The long-dated cured effect is bad.The traditional direct covering pith skill gives up getting rid of the dirt in the cavities in order to avoid the exposed pulp suffering further pollution.The pathologic change of the caries in the dentinoid is divided into disphanotheca, the layer that has gotten rid of mineral,the bacterial invasion layer and the layer that has necrosed to calve from the depth to the surface.There are mineral crystals depositing at the scabrosities of the dentinoid cells or their surroundings.The chronically paratrimma can lead the dentinoid cells to destructure and the pulp to calcify.The layer that has been smirched consists of dentinoid crumblings, destructure collagen, saliva ,bacterium created during prepairing the shape of the cavity.Its thickness is 0.5~5.0 microns.It is loose.It adheres to the surface of the tooth and it is difficult to be gotten rid of.It becomes soft in weeks after plombage and a majority of it is substituted by saliva and bacterium.These can produce the weensy leak around the attal and lead to secondary carises,ecclasis of the attal ,sensitive of teeth, inflammation of the pulp. Er,Cr:YSGG laser that used at dental surgery takes advantage of the principle of the flow mechanics.It is easeful and painless.It has no damage to pulp.It is quick,meticulous and it has no vibration.It can get rid of the dirt and prepair the shape of the cavities safely.It can preserve the wealth structures.The acidoresistance of the strong structure is improved after shined.The shining can not bring hot damage.The reference parameter that Er,Cr:YSGG laser can get rid of the layer that has been smirched is that the shining distance is less than two millimeters,energy is two to three watts and the shining distance is three millimeters, energy is above and beyond four watts. This article studies making use of Er , Cr: YSGG laser to get rid of detritus and the layer that has been smirched to cure unexpected pulp canalization in deep dental caries, judging both curing effect comparatively by histology evaluating comparing with the direct covering pith skill.The laser has the wavelength of 2.78 microns.Its pulse width is 140~200 microns.Its frequency is 20Hz.Its outputting power is 2.2watts and its working distance is 1.0~2.0 millimeters.Its water vapor inverse ratio is 35% germless water vapor and 55% vapor.Purpose:Both curing effects comparatively are judged by histology evaluating when the method making use of Er ,Cr: YSGG laser and calvital to cure unexpected pulp canalization in deep dental caries compares with the direct covering pith skill.Method:Choose 20 cases of such patiants and divided into two groups at random .One group received the therapy of the routine method as collating condition ,another made use of Er , Cr:YSGG laser to get rid of detritus around the pith cavity, displanting the water to shine the exposed tooth pulp at last and use the agentia to covering the pith cavity. Pulling out the 20 teeth in 30 days after operation to make histological evaluation .Result:The microanatomy of the contrasting group shows that there is a repair dentinal formation bridge across the pulp exposure but interrupted and thin.The new differentiating dentinoid cells arrange tidily . Some cells polarise .The capillary vessels in the pulp are hyperaemic and vasodilator .There are more vacuole destructure of the cells and inflammatony cells at different degree in the pulp.The repair dentinal formation bridge that formed by using laser to get rid of detritus is interrupted also but thick .The repair dentinal formation appears tubulous structure .There is a obvious nature dividing line between the repair dentinal formation and the secondary dentinoid.The new differentiating dentinoid cells arrange more tidiler and more and more cells polarize. The capillary vessels under the pericambium are vasodilator .The mechanocytes are hyperplasia .There is not inflammation and destructure in the pulp.Conclusion:1.Two groups have repair dentinal bridge formation.The thicknesses are different .It shows that the functions of the dentinoid appearance cells are different.The function of the group that made use of laser to get rid of detritus is stronger. It is more beneficial to the therapy of the unexpected pulp canalization .2.The new dentinoid appearance cells of the group that made use of laser to get rid of detritus arrange markedly tidily .Most cells polarise.It shows that Er ,Cr: YSGG laser can get rid of detritus and the polluting layer.So,it can clear the irritation that the bacterium and toxin act on the pulps.3.There are not vacuole destructure of the cells and inflammat -ion in the pulps that made use of laser to get rid of detritus. The mechanocytes are hyperplasia. The capillary vessels under the peric -ambium are vasodilator. These show that using the laser displanted the water to shine the exposed tooth pulp can remove the bacteria in the pulps.4. The capillary vessels under the pericambium that made use of laser to get rid of detritus are vasodilator phanerously. The mechanocytes are hyperplasia.Repair dentinoid appears tubiform structrure.These show that the function of the pulp cells is feisty .They are in the state of hyperplasia and differentiation.There are more cells differentiate dentinoid appearance cells to secrete dentinoid substrate. Calvital ions that are supplied by pulp blood vessals go into dentinoid substrate and calcify repaire dentinoid. These show that the total sanatio of the pulp need not only the repaire dentinoid forming but also the hyperplasia mechanocytes and reused vessals.The hyperplasia and differentiation of the pulp cells is the base of the pulp and dentinoid repair and neogenesis. Making use of Er , Cr: YSGG laser to get rid of detritus to cure unexpected pulp canalization in deep dental caries can get rid of the layer that has been smirched.It can also get rid of bacteria and toxin to damage forming dentinoid cells.It can discreate the bacteria in the pulp and provide good condition for the hyperplasia and differentiation of the pulp cells.Calvital has strong alkali .Its PH is 9~12.It can neutralize the acidic product that the inflammation creat.It is good at cancelling inflammation and relieving of pain.The pulp creat coagulative necrosis.There is inflammation reaction under the necrosis and creat dentinoid bridge here.The cells in the pulp differentiate new dentinoid cells.They can secrete dentinoid matrix.The calvital ion that provided by the blood vessels of the pulp enter into the dentinoid matrix and form repair dentinal formation .This experim -ent use Er , Cr:YSGG laser to get rid of detritus and the layer that has been smirched .It can diacreate the bacterium in the exposed pulp and stop the pulp from hemorrhage but not damage the pulp. The laser used here has the wavelength of 2.78 microns.Its pulse width is 140~200 microns.Its frequency is 20Hz.Its outputting power is 2.2watts and its working distance is 1.0~2.0 millimeters.Its water vapor inverse ratio is 35% germless water vapor and 55% vapor.The laser bands together calvital can cure unexpected pulp canalization in deep dental caries more thoroughly and canceling chronic inflammation states of the pulps brought by the direct covering pith skill.The effect can be judged by histology evaluating that is to observe the status of repair dentinal and pulp in 30 days after operation.The means can provide a new train of though that will improve the therapy of protecting the pulp.