Modified resin infiltration of non-, micro- and cavitated proximal caries lesions in vitro.

OBJECTIVE: Infiltrant resin (IR) is currently indicated for non-cavitated caries lesions. However, modifying the technique might expand its indication spectrum to micro-cavitated lesions. The present study aimed to evaluate the penetration/filling ability of a newly developed micro-filled infiltrant resin (MFIR) in non-, micro- and cavitated natural caries lesions. MATERIALS AND METHODS: Proximal lesions in 120 extracted human teeth with ICDAS-2 (n = 30), 3 (n = 45) and 5 (n = 45) lesions were etched with 15% hydrochloric acid gel for 2 min and allocated to one of the following treatments; IR: lesions (ICDAS-2, 3 and 5; each n = 15) were treated with commercial infiltrant resin for 3 min. MFIR: experimental MFIR [55 wt% IR plus 45 wt% organic fillers] was applied to lesions (ICDAS-2, 3 and 5; each n = 15) for 3 min. IR + FC: IR was applied for 3 min, light-cured, and cavities (ICDAS-3 and 5; each n = 15) filled with flowable composite (FC). Percentage infiltration of the demineralized enamel (Inf.%) and percentage filling of the cavity (Fill.%) were analyzed using dual-fluorescence staining and confocal microscopy. RESULTS: No significant differences in Inf.% (range of medians: 57%-100%) were observed between different treatments (p > 0.05; Kruskal-Wallis) within each ICDAS-code. Fill.% of cavities was significantly higher in groups MFIR (median in ICDAS-3/-5: 100%/100%) and IR + FC (100%/100%) than IR (25%/38%) (p < 0.05). CONCLUSION: MFIR showed similar penetration into natural lesions as the commercial infiltrant, but better ability to fill cavitated areas. CLINICAL RELEVANCE: MFIR and IR + FC might provide a new micro-invasive treatment for small cavitated proximal lesions.

Influence of highly concentrated fluoride dentifrices on remineralization characteristics of enamel in vitro.

OBJECTIVES: The aim of this in vitro study was to evaluate the role of highly fluoridated dentifrice on remineralization characteristics of lowly and highly pre-demineralized enamel artificial caries lesions. METHODS: Bovine enamel specimens were prepared (pH 4.95; 21 days) and discriminated in either lowly [L] or highly [H] pre-demineralized artificial caries lesions. Specimens with a mean ΔZbaseline,L (95% CI) of 5120 (4995; 5245) vol.% × µm and a mean ΔZbaseline,H of 8187 (8036; 8339) vol.% × µm were selected and randomly allocated to 12 groups (n = 20). Treatments during pH-cycling (28 days; 6 × 60 min demineralization/day) were brushing 2×/day with fluoride-free (0 ppm F- [L0/H0]), 1100 ppm F- [L1100/H1100], 2800 ppm F- [L2800/H2800], 5000 ppm F- [L5000/H5000], 5000 ppm F- + glycerin [L5000 + glycerin/H5000 + glycerin], and 5000 ppm F- + TCP [L5000 + TCP/H5000 + TCP] containing dentifrices. Dentifrice slurries were prepared with deionized water (1:3wt/wt). After cycling specimens presenting lesion surface loss were discarded and for the remaining 202 specimens, transversal microradiographic (TMR) analyses (ΔZpH-cycle/LDpH-cycle) were performed again. Changes in mineral loss (ΔΔZ = ΔZbaseline - ΔZpH-cycle) and lesion depth (ΔLD = LDbaseline - LDpH-cycle) were calculated. RESULTS: Significant differences for ΔΔZ could be found between L0, L1100, and L5000 as well as H0, H1100, and H2800/H5000 (p ≤ 0.01; ANCOVA). Except for 0 ppm F-, higher ΔΔZ could be found in highly compared with lowly demineralized specimens (p ≤ 0.004; ANCOVA). After pH-cycling, a second lesion front could only be observed in H5000 and H5000 + TCP. The correlation between ΔΔZ and F- was moderate for lowly and highly demineralized lesions (rL = 0.591; pL < 0.001; rH = 0.746; pH < 0.001), indicating a fluoride dose response for both. CONCLUSION: For both baseline substrate conditions, a dose response for fluoride could be revealed. CLINICAL SIGNIFICANCE: Remineralization characteristics of enamel directly depended on baseline mineral loss.

Micro-filled resin infiltration of fissure caries lesions in vitro.

OBJECTIVES: The aim of this in vitro study was to evaluate three treatment modalities [infiltrant resin (IR), micro-filled infiltrant resin (MFIR), infiltrant-sealant-combination (ISC)] regarding both their abilities to penetrate lesions differing in ICDAS-codes and to fill fissures and cavities. MATERIALS AND METHODS: Extracted human molars (n=90) showing fissure caries lesions with and without cavitations were etched with 15% hydrochloric acid (HCl) that was mixed with abrasives and a 15% HCl-solution (1:1). The etching gel was rubbed for 30s within the fissure and, if eligible, within the cavity using a brush. After this pretreatment an infiltrant (Icon; DMG; IR) or an infiltrant mixed with microfillers (MFIR) was applied. ISC included the application of an infiltrant followed by a fissure sealant (Helioseal; Ivoclar Vivadent) From each tooth slices showing a non-cavitated (based on ICDAS-2) or cavitated lesion part (based on ICDAS-3/5) were prepared. Lesion (LA) and penetration areas (PA) as well as the completeness of fissure and cavity filling were analyzed using dual staining and confocal laser scanning microscopy. RESULTS: Percentage penetration (PP) was calculated as 100×PA/LA. PP [median (25th/75th)] did not differ significantly between IR [95 (86/100)%], MFIR [93 (62/100)%] or ISC [89 (67/97)%] (p>0.05; Kruskal-Wallis test). All three materials filled about 90% of the dimensions of fissures and cavities (p>0.05; Kruskal-Wallis test). CONCLUSION: It can be concluded that MFIR seems to be suitable to fill fissures and cavities like a fissure sealant and that it penetrates fissure caries lesions similarly deep as the conventional infiltrant after an experimental etching regime. CLINICAL SIGNIFICANCE: The MFIR seems to combine advantages of the fissure sealing and the caries infiltration procedure.

Comparison of sealant and infiltrant penetration into pit and fissure caries lesions in vitro.

OBJECTIVES: The aim of this in vitro study was to evaluate the penetration of an infiltrant and a sealant, when applied as recommended, into fissure caries lesions. METHODS: The fissure systems of extracted human teeth were classified according to the international caries detection and assessment system (ICDAS, codes: 0, 1, 2). Within each ICDAS-code ten teeth were either etched with 37% H3PO4-gel for 60s and subsequently sealed ('Fissure Sealing'; Helioseal; Ivoclar Vivadent) or etched with 15% HCl-gel for 120s and subsequently infiltrated ('Resin Infiltration'; Icon; DMG). Additionally, ten teeth with ICDAS-code 2 were etched with 37% H3PO4-gel for 120s and infiltrated ('Soft-Etch-Infiltration'). Specimens were cut perpendicular to their surfaces, polished, and confocal microscopic images were obtained. Lesion depths (LDmax) and penetration depths (PDmax) were measured and percentage penetration was calculated as PPmax=PDmax/LDmax×100. RESULTS: Baseline LDmax [median (interquartile range)] for ICDAS-code 2 lesions was 1192 (805-1512)µm. In ICDAS-code 2 lesions PPmax was significantly higher for specimens treated with 'Resin Infiltration' [41 (30-78)%] compared to 'Soft-Etch-Infiltration' [11 (0-21)%] or 'Fissure Sealing' [5 (0-9)%] (p<0.05; Mann-Whitney test). PPmax did not differ significantly between groups in ICDAS-code 0 and 1 lesions (p>0.05). CONCLUSION: The fissure sealant when applied after etching with H3PO4-gel only penetrates superficially into non-cavitated fissure caries lesions. Penetration of an infiltrant is superior in particular after etching with HCl-gel. CLINICAL SIGNIFICANCE: Compared with sealing, infiltration of fissure caries lesions leads to more deeply infiltrated lesions, which might in turn result in superior abilities to hamper caries progression.

Videoteleconferencing: solving mobility and recruitment problems.

Many nurses and nursing students live far from the closest campus or health care agency that can provide basic or continuing education. Videoteleconferencing is one way to bridge this distance. As videoteleconferencing technologies become available and cost effective, nurse educators must be knowledgeable about their use. The authors explain telecommunications technologies of videoteleconferencing, identify advantages and disadvantages, and discuss planning, implementation, and evaluation for offering a program by videoteleconference.