Effects of calcium silicate-based materials on collagen matrix integrity of mineralized dentin.

INTRODUCTION: Calcium silicate-based materials (CSMs) are used in various endodontic procedures. The present study examined whether prolonged contact of mineralized dentin with recently commercialized versions of these materials adversely affects dentin collagen matrix integrity. METHODS: Dentin slabs prepared from extracted human third molars (7 × 3 × 0.3 mm) were divided into 3 groups on the basis of the material to which dentin was exposed (MTA Plus, Biodentine, untreated control dentin slabs) and the time period of exposure (24 hours, 1, 2, and 3 months; n = 6). Hydroxyproline assay was performed on each group's supernatant to quantify the collagen extraction amounts of each group per time period. Data were analyzed with two-factor repeated-measures analysis of variance and Holm-Sidak pair-wise comparisons (α = 0.05) to determine the effects of material and aging time on collagen extraction. Dentin slabs from the 3 months of aging group were demineralized for transmission electron microscopy examination of collagen matrix ultrastructural changes. RESULTS: Material (P = .002), aging time (P < .001), and their interactions (P = .007) significantly affected the amount of hydroxyproline (pg/mg of mineralized dentin) extracted from mineralized dentin and were significantly correlated by power regression models. Collagen degradation was identified from the surface of dentin slabs that were in direct contact with CSMs. CONCLUSIONS: Prolonged contact of mineralized dentin with CSMs has an adverse effect on the integrity of the dentin collagen matrix. However, the amount of collagen extracted was limited to the contact surface. Clinicians can continue to apply CSMs in endodontic procedures; however, caution is advised when these materials are applied to thin dentinal walls.

Effects of calcium silicate-based materials on the flexural properties of dentin.

INTRODUCTION: Prolonged exposure of root dentin to calcium hydroxide alters the fracture resistance of dentin. Calcium silicate-based materials (CSMs) used in endodontics release calcium hydroxide on setting. This study examined whether prolonged contact of dentin with CSMs adversely affects its mechanical properties. METHODS: Dentin beams prepared from extracted human molars (7 × 3 × 0.3 mm) were divided into 3 groups on the basis of the material to which dentin was exposed (Biodentine, MTA Plus, and untreated control beams). Three-point flexure to failure was performed for each beam at designated exposure times (24 hours, 1, 2, and 3 months; n = 10). Data were analyzed with 2-factor repeated-measures analyses of variance to determine the effects of material and aging time on flexural modulus, flexural strength, and modulus of toughness (α = 0.05). RESULTS: For flexural modulus, there was no significant difference for material (P = .947) or aging time (P = .064) when compared with baseline control. For flexural strength, significant differences were associated with aging time (P < .001) but not with material (P = .349). Flexural strength of dentin exposed to Biodentine decreased significantly after 2 and 3 months, whereas that exposed to MTA Plus decreased significantly after 3 months of aging (P < .05). For modulus of toughness, significant declines were observed for both material (P < .004) and aging time (P < .001). CONCLUSIONS: Both CSMs alter material toughness more than the strength and stiffness of dentin after aging in 100% relative humidity. Because dentin toughness is attributed to its collagen matrix, the amount of collagen extracted from mineralized dentin and changes in collagen ultrastructure should be further examined after exposure of dentin to CSMs.

Content validation of terms and definitions in a wound glossary.

OBJECTIVE: A common language and lexicon provide the easiest means of mutual understanding. Inconsistency in terminology makes effective information exchange difficult. Previous studies identified the need to determine standard, accepted definitions for the vocabulary frequently used in wound care. The objective of this study was to establish content validation for these terms and develop an evidence-based glossary for this specialty. METHODS: Members of the Association for the Advancement of Wound Care Quality of Care Task Force reviewed literature to determine glossary content generation and the associated literature-based definitions. Thirty-nine wound care professionals from wound care stakeholder professional organizations in the United States and Canada participated in the content validation process. Participants were asked to quantify the degree of validity using a 367-item, 4-point Likert-type scale. RESULTS: On a scale of 1 to 4, the mean score of the entire instrument was 3.84. The instrument's overall scale content validity index was 0.96. Terms with an item content validity index of less than 0.70 were removed from the glossary, leaving 365 items with established content validity. Qualitative data analysis revealed themes suggesting that enhanced communication between providers improves patient outcomes. The need for ongoing updates of the glossary was also identified. CONCLUSION: The wound care glossary in its finalized form proved valid. An evidence-based glossary bridges the chasm of miscommunication and nonstandardization so that wound care, as an emerging specialized medical science field, can move forward to optimize both process and clinical outcomes.

The AAWC conceptual framework of quality systems for wound care.

When the Association for Advanced Wound Care Quality of Care Task Force members determined there was no unanimously accepted definition of quality as it relates to wound care, they: 1) identified relevant components of quality wound care, and 2) created a framework of quality wound care indicators to enable the creation or assessment of wound care delivery systems. The framework is an innovative conceptual model that serves as a basis for the Association strategies to facilitate high quality wound care for patients/clients across the continuum of care and recognizes the role of the supporting systems necessary to provide wound care services. It uses the Institute of Medicine's Crossing the Quality Chasm: A New Health System for the 21st Century to define quality systems for wound care and includes safety and effectiveness coupled with the delivery of timely, efficient, equitable, collaborative, patient-centered care. This framework can be utilized during clinical, managerial, or regulatory review of wound care service delivery.