Remineralization Of Lesions Research Articles

A Randomized in situ Clinical Study of Fluoride Dentifrices on Enamel Remineralization and Resistance to Demineralization: Effects of Zinc

This study aimed to determine the effect of zinc ions and F concentration in a dentifrice on remineralization of early caries lesions in situ and on resistance to subsequent demineralization. This was a single-center, 6-period, 6-product, blinded (examiner, subject, analyst), randomized (n = 62), crossover study. Products (all NaF) were: 0, 250, 1,150 and 1,426 ppm F (dose-response controls), “Zn-A” (0.3% ZnCl₂, 1,426 ppm F), and “Zn-B” (as Zn-A, with high-foaming surfactants) in a conventional silica base. Subjects wore palatal appliances holding partially demineralized bovine enamel specimens. They brushed their teeth with 1.5 g test dentifrice (25 s), then swished the slurry ensuring even exposure of specimens (95 s), expectorated, and rinsed (15 mL water, 10 s). After 4 h intraoral remineralization, specimens were removed and acid-challenged in vitro. Surface microhardness (SMH), measured pre-experimental, post-initial acid exposure, post-remineralization, and post-second acid exposure, was used to calculate recovery (SMHR), net acid resistance (NAR), and a new, specifically demineralization-focused calculation, “comparative acid resistance” (CAR). Enamel fluoride uptake (EFU) was also measured. For the F dose-response controls, all measures showed significant relationships with dentifrice F concentration (p < 0.0001). The presence of zinc counteracted the ability of F to promote remineralization in this model. Compared to the 1,426 ppm F control, the zinc formulations gave reduced SMHR, EFU, and NAR (all p < 0.0001); however, they showed evidence of increased CAR (Zn-A: p = 0.0040; Zn-B: p = 0.0846). Products were generally well tolerated. In this study, increasing dentifrice F concentration progressively increased in situ remineralization and demineralization resistance of early caries enamel lesions. Zinc ions reduced remineralization but could increase demineralization resistance.

Effectiveness of MI Paste Plus and Remin Pro on remineralization and color improvement of postorthodontic white spot lesions

This clinical trial investigated the effectiveness of two remineralizing creams on regression of white spot lesions (WSLs) after orthodontic therapy. The study included patients with WSLs on their upper anterior teeth who recently completed orthodontic treatment at the Department of Orthodontics of Mashhad Dental School and two private offices. The participants were randomly assigned into three groups by treatment: (1) a 12-week regimen of a cream containing casein phosphopeptide-amorphous calcium phosphate and fluoride (MI Paste Plus); (2) a 12-week regimen of a cream containing hydroxyapatite and fluoride (Remin Pro); and (3) usual home care (control). Thirty-nine patients participated and three withdrew. The main outcomes including area, mineral content, and color of WSLs were measured at enrolment and 4, 8, and 12 weeks later, respectively. Blinding was applied for outcome assessment only. The data were analyzed by analysis of variance and repeated measures analysis at the statistical significance of P < 0.05. Over a 3-month period, the application of both MI Paste Plus and Remin Pro caused significantly greater reduction in area and significantly higher increase in mineral content of WSLs compared to the control group (P < 0.05). The appearance of WSLs improved significantly in both experimental groups (P < 0.05), but not in the control group. No side effect was observed throughout the experiment. The application of either MI Paste Plus or Remin Pro was effective in reducing the area, increasing the mineral content and improving the appearance of demineralized enamel, indicating that these products could be recommended for managing postorthodontic WSLs.

Effect of Two Remineralizing Agents on Initial Caries-like Lesions in Young Permanent Teeth: An in Vitro Study

To compare the effect of nano-hydroxyapatite (9000 ppm F) and casein phosphopeptide-amorphous calcium phosphate fluoride (900 ppm F) pastes on initial enamel carious lesions of young permanent teeth. Sixty extracted young premolars with a standardized window on enamel were immersed in a demineralizing solution for 48 hours to produce subsurface enamel lesions. They were divided into three groups according to remineralizing agents (n = 20) group I: nano-hydroxyapatite paste; group II: casein phosphopeptide-amorphous calcium phosphate fluoride paste; and group III: control (without an agent). The enamel surface microhardness (SMH) was measured at baseline, after the incipient enamel lesion, and after treatment. Additional twenty young premolars were selected and prepared as mentioned above for surface morphology evaluation by scanning electron microscope (SEM). No significant difference was found in mean surface microhardness in teeth treated with nano-hydroxyapatite paste and those treated with casein phosphopeptide-amorphous calcium phosphate fluoride p = 0.26. SEM showed improvement in surface defects of demineralized enamel in the two test groups. Nano-hydroxyapatite and casein phosphopeptide-amorphous calcium phosphate fluoride pastes were effec -tive in rehardening the initial enamel caries lesions in young permanent teeth. The best strategy for caries management is to focus on the methods of improving the reminer-alization process with the aid of the remineralizing agents. The current study compared the remineralizing effect of two remineralizing agents. Within the limitations of the study, both remineralizing agents were effective for remineralization of early caries-like lesions.

A randomised clinical evaluation of a fluoride mouthrinse and dentifrice in an in situ caries model

ObjectivesFluoride mouthrinses provide advantages for fluoride delivery by maintaining elevated intra-oral fluoride concentrations following fluoride dentifrice use. This in situ caries study investigated potential anti-caries efficacy of a 220 ppm fluoride mouthrinse. MethodsThis was an analyst-blinded, four-treatment, randomised, crossover study using partially demineralised, gauze-wrapped, human enamel samples mounted in a mandibular partial denture. Participants brushed twice daily for 14 days with either a 1150 ppm fluoride or a fluoride-free placebo dentifrice and either rinsed once daily with the 220 ppm fluoride mouthrinse or not. Following each treatment period, percent surface microhardness recovery (%SMHR) and enamel fluoride uptake (EFU) were assessed. ResultsFifty three participants completed the study. Compared with the placebo dentifrice/no rinse treatment, the fluoride-containing regimens demonstrated greater enamel remineralisation (%SMHR) and fluoridation (EFU): fluoride dentifrice/fluoride rinse (%SMHR difference: 21.55 [95% CI: 15.78,27.32]; EFU difference 8.35 [7.21,9.29]); fluoride dentifrice/no rinse: 19.48 [13.81,25.15]; 6.47 [5.35,7.60]; placebo dentifrice/fluoride rinse: 16.76 [11.06,22.45]; 5.87 [4.72,7.00] (all P < .0001). There were no significant differences in%SMHR between fluoride regimens. The fluoride dentifrice/fluoride rinse regimen was associated with higher EFU than the fluoride dentifrice/no rinse (1.88 [0.75,3.01], P = .0013) and placebo dentifrice/fluoride rinse regimens (2.48 [1.34,3.62], P < .0001). Treatments were generally well-tolerated. ConclusionsThe in situ caries model demonstrated that the fluoride mouthrinse is effective in promoting enamel caries lesion remineralisation and fluoridation whether used following a fluoride or non-fluoride dentifrice. Additive (potential) anti-caries benefits of a fluoride rinse after a fluoride dentifrice were confined to enhancements in lesion fluoridation (EFU). Clinical significanceIn conjunction with a fluoride dentifrice, fluoride mouthrinses enhance enamel fluoridation, which may be useful in caries prevention.

Using biomimetic polymers in place of noncollagenous proteins to achieve functional remineralization of dentin tissues.

In calcified tissues such as bones and teeth, mineralization is regulated by an extracellular matrix, which includes non-collagenous proteins (NCP). This natural process has been adapted or mimicked to restore tissues following physical damage or demineralization by using polyanionic acids in place of NCPs, but the remineralized tissues fail to fully recover their mechanical properties. Here we show that pre-treatment with certain amphiphilic peptoids, a class of peptide-like polymers consisting of N-substituted glycines that have defined monomer sequences, enhances ordering and mineralization of collagen and induces functional remineralization of dentin lesions in vitro. In the vicinity of dentin tubules, the newly formed apatite nano-crystals are co-aligned with the c-axis parallel to the tubular periphery and recovery of tissue ultrastructure is accompanied by development of high mechanical strength. The observed effects are highly sequence-dependent with alternating polar and non-polar groups leading to positive outcomes while diblock sequences have no effect. The observations suggest aromatic groups interact with the collagen while the hydrophilic side chains bind the mineralizing constituents and highlight the potential of synthetic sequence-defined biomimetic polymers to serve as NCP mimics in tissue remineralization.

Tuberculosis of the Elbow Region in Pediatric Age Group - Experiences from a Single Centre.

Clinical series of tuberculosis of elbow region in children are few. The purpose of our study was to retrospectively review the presentation, healing response and functional results of 30 children. The pretreatment disease presentation was studied from patient's case records. Serial radiographs of the patients were studied to see remineralization and healing of radiological lesions. For elbow's functional evaluation, pain, range of motion and recurrence were observed at final follow up. The mean patient age was 8.2 years. The mean duration of symptoms before presentation was 47 days. A discharging sinus was present in 6 patients. Multifocal presentation was found in 7 patients. The lesion was most commonly localized in proximal ulna or lower humerus. The classical 'ice cream scoop' appearance of proximal ulnar metaphysis was noted in 5 elbows. Most elbows were in Martini stage 2 (70%) at the time of presentation. All patients were treated non-operatively. Average follow up after completion of antitubercular therapy was 18.97 months. The resolution of regional osteopenia, sclerosis of lytic lesions, reappearance of bony trabeculae and decrease in size of cavities was the usual sequence of radiological healing. End average elbow flexion arc deteriorated with increasing Martini stage. 'Ice cream scoop lesions' resulted in a worse functional outcome with formation of an irregular proximal ulnar articular surface. Restriction of elbow range of motion, early discharging sinus formation and radiological 'ice cream scoop' appearance indicated a tubercular pathology. Late presentation with advanced disease, total joint involvement, and 'ice cream scoop appearance' resulted in decreased elbow flexion arc.

In Vitro Comparison Of Fluoride Gel Alone and in Combination With Er,Cr:YSGG Laser on Reducing White Spot Lesions in Primary Teeth.

Introduction: Laser therapy has been suggested as a method for caries-prevention, and ErCr:YSGG laser is increasingly used in dentistry. This study aimed to compare the efficacy of fluoride gel alone and in conjunction with Er,Cr:YSGG laser for remineralization of white spot lesions (WSLs) in primary teeth. Methods: This study was conducted on 20 primary teeth with WSLs extracted for orthodontic reasons. Three sections were made of each tooth at the site of WSLs. The surface area of WSLs was measured under a stereomicroscope at ×25 magnification. Samples were assigned to 3 groups of control (group 1), exposure to 1.23% APF gel for 4 minutes (group 2) and Er,Cr:YSGG laser (0.5 W power, 20 Hz frequency, 60% water, 40% air, pulse duration of 5±1 seconds) plus fluoride (group 3). All samples were stored in artificial saliva for 10 days and then the surface area of the WSLs was measured again under a stereomicroscope. Data were analyzed using the Kruskal-Wallis, MannWhitney and Wilcoxon signed rank tests. Results: The reduction in surface area of the WSLs was significantly different between the control and fluoride (P<0.001) and also the control and laser plus fluoride groups (P<0.001); the difference between fluoride and laser plus fluoride groups was not significant (P=0.265). Comparison of the surface area of WSLs before and after the intervention showed no significant difference in group one (P=0.737) while this difference in groups 2 (P<0.001) and 3 (P<0.001) was statistically significant. Conclusion: The results showed that Er,Cr:YSGG laser irradiation plus 1.23% APF gel was not significantly different from the application of fluoride gel alone in enhancing the remineralization of WSLs.

Silver diamine fluoride remineralized artificial incipient caries in permanent teeth after bacterial pH-cycling in-vitro

ObjectivesTo investigate the remineralizing effect of 38% silver diamine fluoride (SDF) application on enamel artificial caries in adjunct to 1000ppm fluoride toothpaste compared with fluoride toothpaste alone by analyzing the mineral density, depth of remineralization, and remineralization percentage of the lesions. MethodsEighteen artificial caries slabs were created from the proximal surfaces of nine chemically demineralized premolars. The slabs were scanned by Micro-Computed Tomography (Micro-CT) to determine the baseline mineral density of the initial lesions and randomly allocated into 2 groups. The test group was applied with 38% SDF in adjunct to fluoride toothpaste and the control group was treated with fluoride toothpaste alone. The specimens underwent bacterial pH-cycling for 5 d and were re-evaluated using Micro-CT. The pre-treatment and post-treatment mineral densities were plotted and the areas under the curves were used to calculate the remineralization percentage of both groups. ResultsMineral density significantly increased in both groups after pH-cycling (p<0.05) although to different depths (control group=260μm, test group=300μm). The test group demonstrated a significantly higher mineral density to a depth of 120μm and higher remineralization percentage (p<0.05) compared with the control group. ConclusionThe adjunctive use of 38% SDF enhances the remineralization of initial carious lesions based on mineral density, depth, and remineralization percentage compared with the use of 1000ppm fluoride toothpaste alone. SDF might be used as an adjunct to fluoride toothpaste to remineralize incipient caries lesions on smooth tooth surfaces. Clinical significanceIn non-compliant patients, the application of 38% SDF might be used as an adjunct to fluoride toothpaste, to remineralize incipient caries lesions of permanent teeth where esthetics is not a concern.

Self-assembling Peptide P11-4 and Fluoride for Regenerating Enamel

Regenerative medicine-based approaches for caries treatment focus on biomimetic remineralization of initial carious lesions as a minimal invasive therapy. In vitro, self-assembling peptide P11-4 enhances remineralization of early carious lesions. To investigate the safety and clinical efficacy of P11-4 for treatment of initial caries, a randomized controlled single-blind study was conducted on children aged >5 y with visible active early caries on erupting permanent molars. Subjects were randomized to either the test group (P11-4 + fluoride varnish) or control group (fluoride varnish alone). Caries were assessed at baseline and at 3 and 6 mo posttreatment per laser fluorescence, a visual analog scale, the International Caries Detection and Assessment System, and Nyvad caries activity criteria. Intention-to-treat analyses were performed, and safety and clinical feasibility of the treatment approaches were assessed. Compared with the control group, the test group showed clinically and statistically significant improvement in all outcomes at 3 and 6 mo. The laser fluorescence readings (odds ratio = 3.5, P = 0.015) and visual analog scale scores (odds ratio = 7.9, P < .0001) were significantly lower for the test group, and they showed regression in the International Caries Detection and Assessment System caries index (odds ratio = 5.1, P = 0.018) and conversion from active to inactive lesions according to Nyvad criteria (odds ratio = 12.2, P < 0.0001). No adverse events occurred. The biomimetic mineralization facilitated by P11-4 in combination with fluoride application is a simple, safe, and effective noninvasive treatment for early carious lesions that is superior to the presently used gold standard of fluoride alone. By regenerating enamel tissue and preventing lesion progression, this novel approach could change clinical dental practice from a restorative to a therapeutic approach. This could avoid additional loss of healthy hard tissue during invasive restorative treatments, potentially enabling longer tooth life and thereby lowering long-term health costs (ClinicalTrials.gov NCT02724592).

The Effect of Casein Phosphopeptide-amorphous Calcium Fluoride Phosphate on the Remineralization of Artificial Caries Lesions: An In Vitro Study

The studies on electron microstructure of the effect of the use of products that contain casein phosphopeptide-amorphous calcium fluoride phosphate (CPP-ACPF) on enamel remineralization are still needed. It is important method to observe of the morphological changes of teeth in different conditions. Objective: To evaluate the remineralization potential of paste on enamel lesions using scanning electron microscopy (SEM). Methods: Sixty enamel specimens were prepared from extracted human premolars. The specimens were placed in a demineralizing solution for four days to produce artificial carious lesions. The specimens were then randomly assigned to two study groups: group A (control group) and group B. Group B was incubated in remineralizing paste (CPP-ACPF) for 30 minutes per day for 10 days. The control group received no intervention with remineralizing paste. All 60 specimens were stored in artificial saliva at 370C. After remineralization, the samples were observed using SEM. Results : The statistical analysis showed a decrease in the lesion area between the demineralized and remineralized samples, but no significant difference was observed in the lesion depth for group B. There was a significant increase observed in both the lesion depth and lesion area for group A (p = 0.03). Conclusion: The results showed the capacity of CPP-ACPF in supplying calcium and phosphate to the enamel, decreasing the dissolution of the enamel surface and increasing the remineralization of the enamel surface.

A systematic review of silver diamine fluoride: Effectiveness and application in older adults.

This systematic review examines the effectiveness of silver diamine fluoride (SDF) in the management of caries in older adults. Silver diamine fluoride has been extensively researched and proven effective for caries prevention and arrest in children. Limited studies support its effectiveness in adult and older adult populations. Multiple databases were searched according to specified inclusion-exclusion criteria. Quality assessment used modified Centre for Evidence-Based Medicine worksheets. Three randomised controlled trials were identified that addressed the effectiveness of SDF on root caries in older adults, but none addressed coronal caries. Root caries prevented fraction and arrest rate for SDF were significantly higher than placebo. The prevented fraction for caries prevention for SDF compared to placebo was 71% in a 3-year study and 25% in a 2-year study. The prevented fraction for caries arrest for SDF was 725% greater in a 24-month study and 100% greater than placebo in a 30-month study. No severe adverse effects were observed. This systematic review evaluates the use of SDF for both root caries prevention and arrest in older adults. Existing reports of SDF trials support effectiveness in root caries prevention and arrest, remineralization of deep occlusal lesions and treatment of hypersensitive dentin.

Effect of application sequence of fluoride and CPP-ACP on remineralization of white spot lesions in primary teeth: An in-vitro study

ObjectiveTo explore how application sequence of casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) and fluoride influences remineralization of enamel white spot lesions (WSL) in primary teeth. DesignIn this in-vitro study, artificial WSLs were created in 130 primary teeth. Teeth were divided into 4 groups (n=27) and a control group (n=22) and exposed to one of the following remineralization regimens for 10 weeks: Group-1; 500ppm fluoride dentifrice; Group-2; 10% w/v CPP-ACP; Group-3; fluoride applied first, then CPP-ACP; Group-4; CPP-ACP applied first, then fluoride, and Group-5 was control. All groups were kept in a remineralizing solution. Mineral changes (ΔF) were quantified weekly using quantitative light-induced fluorescence. Statistical analysis was done using Statistical Package for the Social Sciences (SPSS version 20.0). ResultsRemineralization occurred in all groups to different degrees; changes from baseline were significant in groups 1–4 (P≤0.05). Group-4 showed the earliest significant remineralization (after 2 weeks) among groups, (P<0.001). Group-4 showed maximum changes in ΔF among groups; however, only differences with Groups 1 and 5 were significant (P<0.05 and P<0.01, respectively). Group-3 showed better remineralization than Groups 1, 2 and 5; however, the difference was only significant with Group-5 (P<0.001). There were no significant differences between Group 1and 2, however, only Group 2 showed better remineralization than Group 5, (P<0.01). ConclusionCombined treatment with CPP-ACP followed by fluoride exhibited the best remineralization of white spot lesions in primary teeth in this study. Combined treatment with fluoride followed by CPP-ACP showed a tendency towards better remineralization than fluoride or CPP-ACP alone.

Effect of calcium phosphate nanocomposite on in vitro remineralization of human dentin lesions

ObjectiveSecondary caries is a primary reason for dental restoration failures. The objective of this study was to investigate the remineralization of human dentin lesions in vitro via restorations using nanocomposites containing nanoparticles of amorphous calcium phosphate (NACP) or NACP and tetracalcium phosphate (TTCP) for the first time. MethodsNACP was synthesized by a spray-drying technique and incorporated into a resin consisting of ethoxylated bisphenol A dimethacrylate (EBPADMA) and pyromellitic glycerol dimethacrylate (PMGDM). After restoring the dentin lesions with nanocomposites as well as a non-releasing commercial composite control, the specimens were treated with cyclic demineralization (pH 4, 1h per day) and remineralization (pH 7, 23h per day) for 4 or 8 weeks. Calcium (Ca) and phosphate (P) ion releases from composites were measured. Dentin lesion remineralization was measured at 4 and 8 weeks by transverse microradiography (TMR). ResultsLowering the pH increased ion release of NACP and NACP-TTCP composites. At 56 days, the released Ca concentration in mmol/L (mean±SD; n=3) was (13.39±0.72) at pH 4, much higher than (1.19±0.06) at pH 7 (p<0.05). At 56 days, P ion concentration was (5.59±0.28) at pH 4, much higher than (0.26±0.01) at pH 7 (p<0.05). Quantitative microradiography showed typical subsurface dentin lesions prior to the cyclic demineralization/remineralization treatment, and dentin remineralization via NACP and NACP-TTCP composites after 4 and 8 weeks of treatment. At 8 weeks, NACP nanocomposite achieved dentin lesion remineralization (mean±SD; n=15) of (48.2±11.0)%, much higher than (5.0±7.2)% for dentin in commercial composite group after the same cyclic demineralization/remineralization regimen (p<0.05). SignificanceNovel NACP-based nanocomposites were demonstrated to achieve dentin lesion remineralization for the first time. These results, coupled with acid-neutralization and good mechanical properties shown previously, indicate that the NACP-based nanocomposites are promising for restorations to inhibit caries and protect tooth structures.

Comparision of two fluoride varnishes for controlling white spot lesions. Randomized clinical trial

Objective: To compare two fluorinated varnishes for the control of white spot lesions.Material and Methods: A randomized controlled clinical trial was conducted. A total of 103 active whitespot lesions on permanent upper anterior teeth from 24 patients, aged 7 to 9 years were randomly assigned totwo groups, G1: Duraphat® (n=52) and G2: DuraShield® (n=51). Weekly applications were perform for fourconsecutive weeks. Fifth week the dimension, regression and activity of the lesions were evaluated. Student’sT test, Wilcoxon Ranks and Chi square were used at 5% significance.&#x0D; Results: At the end of the study, the lesion reduction was observed in 69.7%, finding significant differences(p&lt;0.05) in the mean of the initial and final dimensions in general (2.74 mm to 1.91 mm) and in each group, G1(2.84 mm to 2.03 mm), G2 (2.64 mm to 1.78 mm). In the activity of the lesions, it was found in the G1, 12 active and6 inactive lesions; while in G2, there were 14 active and 29 inactive; these differences were significant (p&lt;0.05).&#x0D; Conclusions: The two evaluated products showed similar clinical efficacy in the remineralization of activewhite spot lesions after 4 weeks of therapy.

Recovery after PILP remineralization of dentin lesions created with two cariogenic acids

ObjectivesAcetate and lactate are important cariogenic acids produced by oral bacteria. They produced different residual dentin structures in artificial lesions of similar depth. We evaluated if such lesions responded in the same way to a polymer-induced-liquid-precursor (PILP) remineralization. DesignDentin blocks obtained from human third molars, divided into 6 groups (n=3). Blocks were demineralized with acetate (66h) or lactate (168h) buffer at pH 5.0 to create 140μm target lesion depths. A-DEM and L-DEM groups received no remineralization. Other groups were remineralized for 14days. 100μg/mL polyaspartate was added into the remineralizing buffer for A-PIL and L-PIL, whereas A-CAP and L-CAP were treated with the same solution but without polyaspartate. Cross-sectioned blocks were examined for shrinkage and AFM-topography. Line profiles of reduced elastic modulus (Er) were obtained by AFM-based nanoindentation across the lesion. Ultrastructures were examined with TEM. ResultsA-PIL and L-PIL recovered in shrinkage to the original height of the dentin and it appeared normal with tubules, with increases in Er at both outer flat and inner sloped zones. At the sloped zone, acetate lesions lost more Er but recovery rate after PILP was not statistically different from lactate lesions. A-CAP and L-CAP showed surface precipitates, significantly less recovery in shrinkage or Er as compared to PILP groups. TEM-ultrastructure of PILP groups showed similar structural and mineral components in the sloped zone for lesions produced by either acid. ConclusionsThe PILP process provided significant recovery of both structure and mechanical properties for artificial lesions produced with acetate or lactate.

Response of carious enamel to TiF4 varnish treatment under diverse cariogenic activities in situ

ObjectiveTo compare the effect of TiF4 and NaF varnishes on demineralized bovine enamel under different cariogenic activities in situ. MethodsTwenty subjects participated of this in situ study with 3 crossover phases (14days each), in which they wore palatal appliances containing demineralized bovine enamel samples (8 samples/appliance for phase) treated with TiF4, NaF (all with 2.45% F) or placebo varnish. The samples were subjected to different cariogenic conditions (1. absence of biofilm accumulation and sucrose exposure; 2. presence of biofilm and absence of sucrose exposure; 3. presence of biofilm and 20% sucrose exposure 4×/day; 4. presence of biofilm and 20% sucrose exposure 8×/day). All were exposed to fluoride dentifrice (2×/day). The mineral content and lesion depth were evaluated using transverse microradiography (TMR) and the data were subjected to RM two-way ANOVA/Bonferroni tests (p<0.05). ResultsTiF4 varnish significantly increased the remineralization of artificial carious lesions compared to placebo, regardless of the cariogenic activity. On the other hand, the remineralizing effect of NaF varnish was dependent on the cariogenic activity. For NaF, remineralization happened only in conditions 1 and 3 compared to placebo varnish (p<0.0001). NaF was unable to prevent further demineralization under biofilm accumulation and sucrose exposure 8×/day (condition 4). In the absence of fluoride treatment, demineralization happened in all conditions, except in the condition 1. ConclusionTherefore, 4% TiF4 varnish was the only treatment able to improve enamel remineralization regardless of the cariogenic activity, while NaF varnish failed in preventing further demineralization under high cariogenic activity in situ. Clinical significance4% TiF4 varnish showed better remineralizing effect compared to NaF varnish, which was seen regardless of the cariogenic activity. This is a promising finding to support the indication of TiF4 in the clinic.

年齢別にみた初期う蝕病巣の進行・回復に及ぼすフッ化物配合歯磨剤の効果について(大阪歯科大学大学院歯学研究科博士(歯学)学位論文内容要旨および論文審査結果要旨の公表)

年齢別にみた初期う蝕病巣の進行・回復に及ぼすフッ化物配合歯磨剤の効果について(大阪歯科大学大学院歯学研究科博士(歯学)学位論文内容要旨および論文審査結果要旨の公表)

Extensive Remineralization of Large Pelvic Lytic Lesions Following Total Therapy Treatment in Patients With Multiple Myeloma.

Osteolytic bone lesions are a hallmark of multiple myeloma (MM) bone disease. Bone destruction is associated with severely imbalanced bone remodeling, secondary to increased osteoclastogenesis and significant osteoblast suppression. Lytic lesions of the pelvis are relatively common in MM patients and are known to contribute to the increased morbidity because of the high risk of fracture, which frequently demands extensive surgical intervention. After observing unexpected radiological improvement in serial large pelvic CT assessment in a patient treated in a total therapy protocol, the radiographic changes of pelvic osteolytic lesions by PET/CT scanning in patients who received Total Therapy 4 (TT4) treatment for myeloma were retrospectively analyzed. Sixty-two (62) patients with lytic pelvic lesions >1 cm in diameter were identified at baseline PET/CT scanning. Follow-up CT studies showed that 27 of 62 patients (43%) with large baseline pelvic lesions achieved significant reaccumulation of radiodense mineralization at the lytic cortical site. The average size of lytic lesions in which remineralization occurred was 4 cm (range, 1.3 to 10 cm). This study clearly demonstrates that mineral deposition in large pelvic lesions occurs in a significant proportion of MM patients treated with TT4, potentially affecting patient outcomes, quality of life, and future treatment strategies. © 2017 American Society for Bone and Mineral Research.

Anticaries Potential of a Sodium Monofluorophosphate Dentifrice Containing Calcium Sodium Phosphosilicate: Exploratory in situ Randomized Trial

Calcium sodium phosphosilicate (CSPS) is a bioactive glass material that alleviates dentin hypersensitivity and is postulated to confer remineralization of caries lesions. This single-centre, randomized, single (investigator)-blind, placebo-controlled, crossover, in situ study explored whether the addition of 5% CSPS to a nonaqueous fluoride (F) such as sodium monofluorophosphate (SMFP)-containing dentifrice affects its cariostatic ability. Seventy-seven subjects wore 4 gauze-covered enamel specimens with preformed lesions (2 surface-softened and 2 subsurface) placed buccally on their mandibular bilateral dentures for up to 4 weeks. Subjects brushed twice daily with 1 of the 5 study dentifrices: 927 ppm F/5% CSPS, 927 ppm F/0% CSPS, 250 ppm F/0% CSPS, 0 ppm F/5% CSPS, or 0 ppm F/0% CSPS. Specimens were retrieved after either 21 (surface-softened lesions; analyzed by Knoop surface microhardness [SMH]) or 28 days (subsurface lesions; analyzed by transverse microradiography). The enamel fluoride uptake was determined for all specimens using a microbiopsy technique. The concentrations of fluoride and calcium in gauze-retrieved plaque were also evaluated. Higher dentifrice fluoride concentrations led to greater remineralization and fluoridation of both lesion types and increased plaque fluoride concentrations. CSPS did not improve the cariostatic properties of SMFP; there were no statistically significant differences between 927 ppm F/5% CSPS and 927 ppm F/0% CSPS in percent SMH recovery (p = 0.6788), change in integrated mineral loss (p = 0.5908), or lesion depth (p = 0.6622). Likewise, 0 ppm F/5% CSPS did not provide any benefits in comparison to 0 ppm F/0% CSPS. In conclusion, CSPS does not negatively impact nor does it improve the ability of an SMFP dentifrice to affect remineralization of caries lesions.

Warmed acidulated phosphate fluoride enhances release of fluoride from human enamel surfaces, promoting lesion remineralization in vitro and in situ

BackgroundThe calcium fluoride-like material deposited on the enamel surface is important as a fluoride reservoir. Elevated temperatures significantly increase the acquisition of KOH-soluble fluoride on sound tooth surfaces in vitro. MethodsWe investigated the efficacy of warmed APF solution on remineralization of subsurface enamel lesions, both in vitro and in situ. Hardness recovery was measured every week for 4 weeks to assess remineralization efficacy, and the behavior of fluoride release from sound and demineralized enamel with APF solution applied at 25 °C and 50°C was compared. ResultsApplication of APF to enamel at 50 °C showed a significantly greater degree of F− release up to 18 h than the 25 °C group in sound specimens and up to 48 h in demineralized specimens. Moreover, longer-lasting and greater amounts of F− release were observed in demineralized specimens versus sound specimens. The profiles of changes in hardness over time in vitro and in situ showed that the hardness was significantly greater in the 50 °C group than in the 25 °C and control groups at all measurement points and the mean value of the hardness recovery in the 25 °C and 50 °C groups was observed by 2 weeks, although a significant increase was only noted from baseline to 1 week in the 25 °C group. Overall, the recovery of hardness was inadequate, compared to the original enamel. ConclusionIn conclusion, application of the warmed APF solution to the demineralized enamel lesion showed potential to increase the fluoride release and enhance the rate of remineralization than that at 25 °C.