Txhuam hniav txhuam hniav

Txhua tus neeg xav kom muaj cov hniav dawb dawb. Tom qab tag nrho, raws li lawv hais "sib ntsib ntawm cov khaub ncaws." Lub luag nyav yog dab tsi ntau tus neeg xyuam xim thaum lawv ntsib. Yog li ntawd, dawb cov hniav nyob rau hauv peb lub sij hawm ntau dua ib qho tseem ceeb tshaj ib tug whim. Kev yoojyim tshaj plaws thiab yooj yim rau kev siv tus kheej yog siv cov tshuaj txhuam hniav kom zoo.

Cov tshuaj txhuam hniav twg zoo dua?

Lub mechanism ntawm kev txiav txim ntawm cov nyhuv xim ntawm pastes yuav txawv. Qee cov pastes ua los ntawm kev ntxuav lub qhov ncauj ntawm lub qhov ncauj ntawm pob txha ntawm qhov pigment pob, dyes, cov quav hniav thiab cov pob zeb. Ntawd yog, lawv muaj cov khoom zoo abrasive. Ntxiv rau cov khoom tawg, xws li cov khoom siv kuj muaj xws li:

• polishing cov khoom uas ua rau cov hniav zoo tom qab tu;
• enzymes thiab pyrophosphates, dissolving lub quav hniav, uas muaj txhawb rau ib tug zoo dua tshem tawm ntawm nws los ntawm cov hniav.

Feem ntau, tus kws kho hniav muab tswv yim rau kev siv cov tshuaj muab tshuaj thaiv ob peb zaug ib lub lim tiam. Kev tu txhua hnub tsis tuaj yeem ceev cov txheej txheem ntxuav hniav dawb, tab sis nws tuaj yeem ua mob rau cov hniav.

Vim muaj kev txhawj xeeb, cov tshuaj siv yuav tsum tau siv nrog kev saib xyuas, vim hais tias qee tus neeg lawv siv lawv tuaj yeem ua rau muaj zog ntawm tus hniav laus thiab txawm tias muaj erosion los yog cov kab tsis zoo. Feem ntau, cov tshuaj fluorides ntxiv rau cov khoom siv, uas ua rau kom tsis txhob muaj teeb meem li no. Tab sis yog tias cov pob txha tsis muaj kab mob twb tuaj nyob hauv lub qhov ncauj, ces siv qhov tseem zoo tshaj plaws thiab zoo tshaj plaws txhuam hniav cov tshuaj txhuam hniav yog contraindicated.

Cov tshuaj txhuam hniav dawb tsis zoo

Txhuam cov tshuaj txhuam hniav ntawm lwm qhov kev ua haujlwm ntawm kev siv nyiaj nquag oxygen. Nws los qhov twg los? Nws yooj yim - qhov muab tshuaj txhuam muaj carbamide peroxide los yog hydrogen peroxide . Kev nkag mus rau hauv lub qhov ncauj, cov tshuaj ua ke nrog cov qaub ncaug thiab zuaj siab, ua kom tsis txhob muaj cov pa oxygen. Xws li oxygen penetrates tob rau hauv cov ntaub so ntswg tawv ntawm cov hniav thiab tshem tawm pigmented me ntsis uas tsis tau muab tshem tawm nrog abrasive pastes. Tsis tas li ntawd, pastes tiv thaiv cov tsos ntawm cov quav hniav tshiab, zais cov hniav nrog ib zaj duab xis ultrathin.

Cov qoob loo uas tsis yog abrasive kuj tseem muaj tshuaj fluorides hauv lawv cov khoom, uas tau tiv thaiv kev tiv thaiv ntawm cov kab mob thiab qhov muag ntawm cov hniav. Thiab tom qab kawm tiav ntawm tus kws kho mob tuaj yeem qhia koj txog kev ntxuav hniav nrog cov pastes uas muaj calcium npaj rau saturate cov hniav nrog cov zaub mov.