title: Effects of toothbrushing force on the mineral content and demineralized organic matrix of eroded dentine.
abstract: Eroded dentine has a complex histological structure, and its organic fraction becomes increasingly exposed as a result of the continual action of acids. The present study sought to investigate the effects of brushing forces up to 4 N on mineralized and organic dentine fractions. The study was a cyclic demineralization and remineralization experiment (carried out over 9 d). Erosion was performed with HCl (6 x 2 min d-1), pH 1.6. Samples exposed to erosion alone served as controls; test samples were eroded and brushed with a powered toothbrush (2 x 15 s d-1), applying forces of 2, 3, or 4 N. Samples were analysed (using profilometry and longitudinal microradiography) before and after the removal of superficial organic material with collagenase. Randomly selected samples were subjected to scanning electron microscopy. Demineralized organic material was present on all samples regardless of brushing force. Loss values (determined using profilometry) after erosion only, and after brushing with forces of 2, 3, and 4 N, were 11.7 +/- 5.1, 13.6 +/- 11.2, 30.7 +/- 19.0, and 25.5 +/- 20.3, respectively, before treatment with collagenase, and 111.7 +/- 11.6, 122.0 +/- 11.8, 121.9 +/- 15.7, and 123.0 +/- 12.0, respectively, after treatment with collagenase. Microradiography confirmed the results. Significant effects of brushing force were only found on the demineralized organic fraction, and mineral loss was unaffected. The notion that eroded dentine is particularly prone to abrasion should be reconsidered.
authors: Department of Conservative and Preventive Dentistry, Dental Clinic, Giessen, Germany. carolina.ganss@dentist.med.uni-giessen.de
authors: Carolina
authors: C
authors: Ganss
authors: Martin
authors: M
authors: Hardt
authors: David
authors: D
authors: Blazek
authors: Joachim
authors: J
authors: Klimek
authors: Nadine
authors: N
authors: Schlueter
mesh_terms: D001696:Biomechanical Phenomena; D002122:Calcium Chloride / Q000008:administration & dosage; D002254:Carbonates / Q000008:administration & dosage; D017364:Collagenases / Q000008:administration & dosage; D003648:Decalcification Technique; D003804:Dentin / Q000737:chemistry* / Q000648:ultrastructure; D017886:Durapatite / Q000008:administration & dosage; D006801:Humans; D006851:Hydrochloric Acid / Q000009:adverse effects; D006863:Hydrogen-Ion Concentration; D008852:Microradiography; D008855:Microscopy, Electron, Scanning; D008903:Minerals / Q000032:analysis*; D010756:Phosphoric Acids / Q000008:administration & dosage; D011189:Potassium Chloride / Q000008:administration & dosage; D013314:Stress, Mechanical; D014072:Tooth Abrasion / Q000378:metabolism / Q000473:pathology; D017001:Tooth Demineralization / Q000378:metabolism* / Q000473:pathology; D014077:Tooth Erosion / Q000378:metabolism* / Q000473:pathology; D014089:Tooth Remineralization; D014099:Toothbrushing / Q000295:instrumentation
chemical_list: D002254:Carbonates; D008903:Minerals; D010756:Phosphoric Acids; C005686:sodium carbonate; D011189:Potassium Chloride; D017886:Durapatite; C030242:phosphoric acid; D017364:Collagenases; D002122:Calcium Chloride; D006851:Hydrochloric Acid