The role of protease inhibitors on the remineralization of demineralized dentin using the PILP method.

Mineralized and sound dentin matrices contain inactive preforms of proteolytic enzymes that may be activated during the demineralization cycle. In this study, we tested the hypothesis that protease inhibitors (PI) preserve demineralized collagen fibrils and other constituents of the dentin matrix an...

Full description

Bibliographic Details
Main Authors: Hamid Nurrohman, Karina M M Carneiro, John Hellgeth, Kuniko Saeki, Sally J Marshall, Grayson W Marshall, Stefan Habelitz
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2017-01-01
Series:PLoS ONE
Online Access:http://europepmc.org/articles/PMC5705123?pdf=render
_version_ 1818128171528093696
author Hamid Nurrohman
Karina M M Carneiro
John Hellgeth
Kuniko Saeki
Sally J Marshall
Grayson W Marshall
Stefan Habelitz
author_facet Hamid Nurrohman
Karina M M Carneiro
John Hellgeth
Kuniko Saeki
Sally J Marshall
Grayson W Marshall
Stefan Habelitz
author_sort Hamid Nurrohman
collection DOAJ
description Mineralized and sound dentin matrices contain inactive preforms of proteolytic enzymes that may be activated during the demineralization cycle. In this study, we tested the hypothesis that protease inhibitors (PI) preserve demineralized collagen fibrils and other constituents of the dentin matrix and thereby affect the potential for remineralization. Artificial carious lesions with lesion depths of 140 μm were created with acetate buffer (pH = 5.0, 66 hours), and remineralized using a polymer-induced-liquid-precursor (PILP) process (pH = 7.4, 14 days) containing poly(aspartic acid) (pAsp) as the process-directing agent. De- and remineralizing procedures were performed in the presence or absence of PI. Ultrastructure and mechanical recovery of demineralized dentin following PILP remineralization were examined and measured in water with atomic force microscopy (AFM) and nanoindentation. Nanomechanical properties of hydrated artificial lesions had a low elastic modulus (ER <0.4 GPa) extending about 100 μm into the lesion, followed by a sloped region of about 140 μm depth where values reached those of normal dentin (18.0-20.0 GPa). Mapping of mineral content by both micro-FTIR and micro x-ray computed tomography correlated well with modulus profiles obtained by nanoindentation. Tissue demineralized in the presence of PI exhibited higher elastic moduli (average 2.8 GPa) across the lesion and comprised a narrow zone in the outer lesion with strongly increased modulus (up to 8 GPa; p < 0.05), which might be related to the preservation of non-collagenous proteins that appear to induce calcium phosphate mineral formation even under demineralizing physical-chemical conditions. However, mechanical aspects of remineralization through the elastic modulus change, and the micromorphological aspects with SEM and TEM observation were almost identical with PILP treatments being conducted in the presence or absence of PI. Thus, the application of the protease inhibitors (PI) seemed to be less effective in promoting the remineralization of demineralized dentin.
first_indexed 2024-12-11T07:29:01Z
format Article
id doaj.art-75c6080a8faa45b6b54f48867efe6efe
institution Directory Open Access Journal
issn 1932-6203
language English
last_indexed 2024-12-11T07:29:01Z
publishDate 2017-01-01
publisher Public Library of Science (PLoS)
record_format Article
series PLoS ONE
spelling doaj.art-75c6080a8faa45b6b54f48867efe6efe2022-12-22T01:15:53ZengPublic Library of Science (PLoS)PLoS ONE1932-62032017-01-011211e018827710.1371/journal.pone.0188277The role of protease inhibitors on the remineralization of demineralized dentin using the PILP method.Hamid NurrohmanKarina M M CarneiroJohn HellgethKuniko SaekiSally J MarshallGrayson W MarshallStefan HabelitzMineralized and sound dentin matrices contain inactive preforms of proteolytic enzymes that may be activated during the demineralization cycle. In this study, we tested the hypothesis that protease inhibitors (PI) preserve demineralized collagen fibrils and other constituents of the dentin matrix and thereby affect the potential for remineralization. Artificial carious lesions with lesion depths of 140 μm were created with acetate buffer (pH = 5.0, 66 hours), and remineralized using a polymer-induced-liquid-precursor (PILP) process (pH = 7.4, 14 days) containing poly(aspartic acid) (pAsp) as the process-directing agent. De- and remineralizing procedures were performed in the presence or absence of PI. Ultrastructure and mechanical recovery of demineralized dentin following PILP remineralization were examined and measured in water with atomic force microscopy (AFM) and nanoindentation. Nanomechanical properties of hydrated artificial lesions had a low elastic modulus (ER <0.4 GPa) extending about 100 μm into the lesion, followed by a sloped region of about 140 μm depth where values reached those of normal dentin (18.0-20.0 GPa). Mapping of mineral content by both micro-FTIR and micro x-ray computed tomography correlated well with modulus profiles obtained by nanoindentation. Tissue demineralized in the presence of PI exhibited higher elastic moduli (average 2.8 GPa) across the lesion and comprised a narrow zone in the outer lesion with strongly increased modulus (up to 8 GPa; p < 0.05), which might be related to the preservation of non-collagenous proteins that appear to induce calcium phosphate mineral formation even under demineralizing physical-chemical conditions. However, mechanical aspects of remineralization through the elastic modulus change, and the micromorphological aspects with SEM and TEM observation were almost identical with PILP treatments being conducted in the presence or absence of PI. Thus, the application of the protease inhibitors (PI) seemed to be less effective in promoting the remineralization of demineralized dentin.http://europepmc.org/articles/PMC5705123?pdf=render
spellingShingle Hamid Nurrohman
Karina M M Carneiro
John Hellgeth
Kuniko Saeki
Sally J Marshall
Grayson W Marshall
Stefan Habelitz
The role of protease inhibitors on the remineralization of demineralized dentin using the PILP method.
PLoS ONE
title The role of protease inhibitors on the remineralization of demineralized dentin using the PILP method.
title_full The role of protease inhibitors on the remineralization of demineralized dentin using the PILP method.
title_fullStr The role of protease inhibitors on the remineralization of demineralized dentin using the PILP method.
title_full_unstemmed The role of protease inhibitors on the remineralization of demineralized dentin using the PILP method.
title_short The role of protease inhibitors on the remineralization of demineralized dentin using the PILP method.
title_sort role of protease inhibitors on the remineralization of demineralized dentin using the pilp method
url http://europepmc.org/articles/PMC5705123?pdf=render
work_keys_str_mv AT hamidnurrohman theroleofproteaseinhibitorsontheremineralizationofdemineralizeddentinusingthepilpmethod
AT karinammcarneiro theroleofproteaseinhibitorsontheremineralizationofdemineralizeddentinusingthepilpmethod
AT johnhellgeth theroleofproteaseinhibitorsontheremineralizationofdemineralizeddentinusingthepilpmethod
AT kunikosaeki theroleofproteaseinhibitorsontheremineralizationofdemineralizeddentinusingthepilpmethod
AT sallyjmarshall theroleofproteaseinhibitorsontheremineralizationofdemineralizeddentinusingthepilpmethod
AT graysonwmarshall theroleofproteaseinhibitorsontheremineralizationofdemineralizeddentinusingthepilpmethod
AT stefanhabelitz theroleofproteaseinhibitorsontheremineralizationofdemineralizeddentinusingthepilpmethod
AT hamidnurrohman roleofproteaseinhibitorsontheremineralizationofdemineralizeddentinusingthepilpmethod
AT karinammcarneiro roleofproteaseinhibitorsontheremineralizationofdemineralizeddentinusingthepilpmethod
AT johnhellgeth roleofproteaseinhibitorsontheremineralizationofdemineralizeddentinusingthepilpmethod
AT kunikosaeki roleofproteaseinhibitorsontheremineralizationofdemineralizeddentinusingthepilpmethod
AT sallyjmarshall roleofproteaseinhibitorsontheremineralizationofdemineralizeddentinusingthepilpmethod
AT graysonwmarshall roleofproteaseinhibitorsontheremineralizationofdemineralizeddentinusingthepilpmethod
AT stefanhabelitz roleofproteaseinhibitorsontheremineralizationofdemineralizeddentinusingthepilpmethod