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1.
J Pers Med ; 11(3)2021 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-33806927

RESUMO

This study investigated the potential of salivary bacterial and protein markers for evaluating the disease status in healthy individuals or patients with gingivitis or caries. Saliva samples from caries- and gingivitis-free individuals (n = 18), patients with gingivitis (n = 17), or patients with deep caries lesions (n = 38) were collected and analyzed for 44 candidate biomarkers (cytokines, chemokines, growth factors, matrix metalloproteinases, a metallopeptidase inhibitor, proteolytic enzymes, and selected oral bacteria). The resulting data were subjected to principal component analysis and used as a training set for random forest (RF) modeling. This computational analysis revealed four biomarkers (IL-4, IL-13, IL-2-RA, and eotaxin/CCL11) to be of high importance for the correct depiction of caries in 37 of 38 patients. The RF model was then used to classify 10 subjects (five caries-/gingivitis-free and five with caries), who were followed over a period of six months. The results were compared to the clinical assessments of dental specialists, revealing a high correlation between the RF prediction and the clinical classification. Due to the superior sensitivity of the RF model, there was a divergence in the prediction of two caries and four caries-/gingivitis-free subjects. These findings suggest IL-4, IL-13, IL-2-RA, and eotaxin/CCL11 as potential salivary biomarkers for identifying noninvasive caries. Furthermore, we suggest a potential association between JAK/STAT signaling and dental caries onset and progression.

2.
Artigo em Inglês | MEDLINE | ID: mdl-33478112

RESUMO

Enzymes in toothpastes can support host immune responses, and thus maintain oral health. This study aimed to investigate gingival health and the plaque-reducing effects of enzyme-containing toothpastes. A laboratory study tested the antimicrobial potential of different enzyme-containing toothpaste formulations. Two promising formulations (enzyme-containing toothpastes with glucose oxidase and D-glucose with (C+) and without Citrox (C-) Citrox) were investigated in a clinical crossover trial (two slurries: sodium lauryl sulfate-containing (SLS), a toothpaste without SLS (reference), and water). Subjects (n = 20) abstained from toothbrushing for four days and rinsed with a toothpaste slurry. Bleeding on probing (BOP) and plaque indices (PI) were measured. A mixed linear model was used to statistically compare the slurries with respect to BOP and PI change. The in vitro bacterial growth-inhibiting evaluation showed the best results for SLS, followed by C+ and C-. The change in BOP and PI exhibited statistically significant differences to water rinsing (BOP; PI changes in % points (difference of the baseline and post-rinse values: water = 8.8%; 90.0%; C+ = -1.4%; 80.4%; SLS = 1.5%; 72.1%; reference = 0.8%; 77.5%; C- = -1.8%; 75.1%). All slurries exhibited anti-gingivitis and anti-plaque effects, resulting in a prophylactic benefit for limited-access regions during brushing.


Assuntos
Gengivite , Cremes Dentais , Método Duplo-Cego , Gengiva , Humanos , Dodecilsulfato de Sódio , Escovação Dentária
3.
Materials (Basel) ; 13(20)2020 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-33050594

RESUMO

Good margin integrity with a tight seal of the adhesive interface is considered one of the key factors for the clinical success of composite restorations. This study investigated the effect of enamel etching with phosphoric acid on the margin integrity of self-etch bonded composite restorations in demineralized enamel. Crowns of bovine incisors were assigned into 14 groups (n = 10 per group) of which ten groups (groups 1-5 and 8-12) were demineralized (21 days, acid buffer, pH 4.95) to create artificial carious lesions. Standardized Class V cavities were prepared in all specimens. Demineralized groups were either etched with phosphoric acid for 10, 30, 60, or 120 s (groups 2-5 and 9-12), or no etching was performed (groups 1 and 8). The non-demineralized (sound) groups were etched for 10 s (groups 7 and 14) or remained non-etched (groups 6 and 13). Resin composite restorations were then placed using either a one-step (iBond Self Etch, groups 1-7) or two-step self-etch adhesive (Clearfil SE Bond, groups 8-14). Margin integrity of the restorations was assessed after thermocycling (5000×, 5-55 °C) using scanning electron microscopy, and the percentage of continuous margins (%CM) was statistically analyzed (α = 0.05). Phosphoric acid etching significantly increased %CM in both demineralized and sound enamel. For iBond Self Etch, a significant increase in %CM in demineralized enamel was observed with increased etching times. All etched groups treated with Clearfil SE Bond and those etched for 60 or 120 s and treated with iBond Self Etch showed similar %CM in demineralized enamel as in etched sound enamel, and significantly higher %CM than in non-etched sound enamel. In conclusion, enamel etching with phosphoric acid improves margin integrity of composite restorations in demineralized enamel when bonded with the examined adhesives.

4.
J Clin Med ; 9(9)2020 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-32933084

RESUMO

Oral health is maintained by a healthy microbiome, which can be monitored by state-of-the art diagnostics. Therefore, this study evaluated the presence and quantity of ten oral disease-associated taxa (P. gingivalis, T. forsythia, T. denticola, F. nucleatum, C. rectus, P. intermedia, A. actinomycetemcomitans, S. mutans, S. sobrinus, oral associated Lactobacilli) in saliva and their clinical status association in 214 individuals. Upon clinical examination, study subjects were grouped into healthy, caries and periodontitis and their saliva was collected. A highly specific point-of-care compatible dual color qPCR assay was developed and used to study the above-mentioned bacteria of interest in the collected saliva. Assay performance was compared to a commercially available microbial reference test. Eight out of ten taxa that were investigated during this study were strong discriminators between the periodontitis and healthy groups: C. rectus, T. forsythia, P. gingivalis, S. mutans, F. nucleatum, T. denticola, P. intermedia and oral Lactobacilli (p < 0.05). Significant differentiation between the periodontitis and caries group microbiome was only shown for S. mutans (p < 0.05). A clear distinction between oral health and disease was enabled by the analysis of quantitative qPCR data of target taxa levels in saliva.

5.
Caries Res ; : 1-7, 2020 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-32998154

RESUMO

OBJECTIVES: This in vitro study aimed to evaluate and compare the effect of two different bioactive glasses, a hydroxyapatite-containing, fluoride-free toothpaste (HTP) and a fluoride toothpaste (FTP) on the remineralization behavior of initial caries lesions. MATERIALS AND METHODS: A total of 100 bovine enamel samples were randomly allocated to five groups of 20 samples each: NC = negative control group (artificial saliva); HTP = HTP group (Karex); FTP = FTP group (Elmex caries protection, 1,400 ppm); FTP + BGnano = FTP followed by Actimins bioactive glass; FTP + BGamorph = FTP followed by Schott bioactive glass. Radiographic documentation (advanced transversal microradiography; aTMR) was applied before and after all samples were exposed to a demineralizing gel for 10 days. Over a period of 28 days, samples were covered twice a day (every 12 h) with a toothpaste slurry of the respective test group or with artificial saliva in NC for 60 s and brushed with 15 brushing strokes. Samples in FTP + BGnano and FTP + BGamorph were additionally treated with the respective bioactive glass slurry for 30 s after brushing with the FTP. In the meantime, all samples were stored in artificial saliva. After 28 days, the structure of all samples was assessed again using aTMR and compared to the values measured after demineralization. The statistical evaluation of the integrated mineral loss was performed using Kruskal-Wallis test followed by a post hoc Conover test. RESULTS: The FTP revealed the significantly highest increase of mineral content while the HTP showed the significantly lowest remineralization. Compared to artificial saliva, the use of the HTP or the combined application of FTP followed by bioactive glasses (FTP + BGnano and FTP + BGamorph) showed no significant remineralization. CONCLUSION: Under remineralizing in vitro conditions, brushing with 1,400 ppm FTP induced significantly more remineralization compared to storage in artificial saliva. The additional administration of both bioactive glasses as well as the substitutional brushing with an HTP resulted in significantly less remineralization compared to brushing with 1,400 ppm FTP.

6.
Materials (Basel) ; 13(15)2020 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-32748827

RESUMO

In vitro studies investigating the mechanical properties of dental reconstructions use various materials to replicate prepared teeth. However, no uniform recommendation exists as to which material is most suitable for standardized testing. The purpose of this study was to identify a material that resembles human dentin in fracture load tests. Sixteen human teeth were scanned with an intraoral scanner to obtain copies of the original crown morphology and were then prepared for crowns. Replica dies of the prepared teeth including the root morphology were fabricated with a Computer-aided design and computer-aided manufacturing (CAD/CAM) system and divided into four groups: (A) reinforced composite (RC); (B) human dentin (HD); (C) polymethyl methacrylate (PM); and (D) hybrid ceramic (HC). Sixty-four feldspar ceramic crowns were designed with the biocopy mode, fabricated with a CAD/CAM system, luted on the dies, and then with the roots embedded in polymethyl methacrylate. Care was taken to position all specimens of the same morphology identically. Thermo-mechanical load cycling was performed in a chewing simulator followed by fractural loading of the crowns. A mixed effect linear model was fitted to the data, and pairwise contrasts were estimated on the marginal means and corrected for multiple testing according to Tukey (α = 0.05). The means for fracture load (N) were 2435 N (95% CI (2162, 2709)) for hybrid ceramic, 1838 N (95% CI (1565, 2112)) for reinforced composite, 1670 N (95% CI (1396, 1943)) for human tooth and 1142 N (95% CI (868, 1415)) for polymethyl methacrylate abutment materials. Post-hoc pairwise contrasts revealed a statistically significant (p < 0.05) difference among all groups except for reinforced composite and human dentin (p = 0.76). The results indicate that the mechanical properties of abutment dies play a significant role for a possible substitution of natural teeth in in vitro studies.

7.
J Adhes Dent ; 22(4): 365-372, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32666062

RESUMO

PURPOSE: To investigate the reparability of aged and fresh resin composite after different mechanical surface pretreatments. MATERIALS AND METHODS: Sixty composite specimens (Filtek Supreme XTE, 3M Oral Care) were either aged by thermal cycling (5000 cycles, 5-55°C) and six months of water storage, or immediately processed within 5 min after polymerization. Both aged and fresh specimens were either ground with fine (46-µm) or coarse (100-µm) diamond burs and then silanized or sandblasted with aluminum oxide (Al2O3) and silanized. In the negative control group, no mechanical surface pretreatment or silanization was performed. Specimens (n = 6 per group) were repaired with an adhesive (OptiBond FL, Kerr) and a resin composite (Filtek Supreme XTE). Directly adhered composite-to-composite increments served as the positive control group. After thermoycling, microtensile repair bond strength was assessed and statistically analyzed (α = 0.05). RESULTS: Aged composite surfaces revealed significantly lower repair bond strength than immediately repaired composite. The negative control group demonstrated the significantly lowest microtensile bond strength of all groups. No significant differences in repair bond strength were observed between the different mechanical pretreatments for both aged and fresh specimens. The repair bond strength of fresh composite pretreated with a fine diamond bur + Al2O3 + silane or a coarse diamond bur with/without Al2O3 + silane did not differ significantly from the positive control group. CONCLUSION: The age of the repaired composite has a greater influence on repair bond strength than does the type of composite surface pretreatment.


Assuntos
Colagem Dentária , Resinas Compostas , Teste de Materiais , Silanos , Estresse Mecânico , Propriedades de Superfície , Resistência à Tração
8.
Swiss Dent J ; 130(7-8): 572-583, 2020 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-32515568

RESUMO

The aim of this systematic review was to compare the combination of amoxicillin and metronidazole or azithromycin when used as adjunct systemic antibiotics during the non-surgical periodontal therapy of chronic periodontitis. The databases Medline, Embase, Cochrane and Biosis were electronically searched. Additionally, a hand search was conducted up to24 October 2019. From 76 papers, only two papers could be included in the analysis. The calculated mean probability of having probing depth (PD) ≤ 3 mm after non-surgical periodontal therapy in moderate (4-6 mm) and deep (> 6 mm) pockets accounted for 7% and 6% for the combination of amoxicillin and metronidazole. For azithromycin it was 3% and 1%, respectively. The mean probability of persisting pockets ≥ 5 mm was 0 for moderate pockets with both antibiotic therapies whereas for deep pockets therapy with amoxicillin and metronidazole seems slightly lower. On the basis of two studies included in this systematic review, azithromycin as an adjunct to scaling and root planing in the non-surgical adjunctive treatment of chronic periodontitis seems to provide clinical results similar to the combination of amoxicillin and metronidazole. On behalf of patients' compliance and well-being, the use of azithromycin as an adjunct to non-surgical periodontal therapy of chronic periodontitis may be a substitute to amoxicillin and metronidazole. However, interpretation should be taken with caution, since the results are based on two studies only; thus, further clinical trials are necessary to underline or refute this trend.


Assuntos
Amoxicilina , Metronidazol , Antibacterianos/uso terapêutico , Azitromicina , Raspagem Dentária , Humanos , Aplainamento Radicular
9.
Microorganisms ; 8(5)2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32369987

RESUMO

This review aimed to systematically compare microbial profiles of peri-implantitis to those of periodontitis and healthy implants. Therefore, an electronic search in five databases was conducted. For inclusion, studies assessing the microbiome of peri-implantitis in otherwise healthy patients were considered. Literature was assessed for consistent evidence of exclusive or predominant peri-implantitis microbiota. Of 158 potentially eligible articles, data of 64 studies on 3730 samples from peri-implant sites were included in this study. Different assessment methods were described in the studies, namely bacterial culture, PCR-based assessment, hybridization techniques, pyrosequencing, and transcriptomic analyses. After analysis of 13 selected culture-dependent studies, no microbial species were found to be specific for peri-implantitis. After assessment of 28 studies using PCR-based methods and a meta-analysis on 19 studies, a higher prevalence of Aggregatibacter actinomycetemcomitans and Prevotella intermedia (log-odds ratio 4.04 and 2.28, respectively) was detected in peri-implantitis biofilms compared with healthy implants. Actinomyces spp., Porphyromonas spp. and Rothia spp. were found in all five pyrosequencing studies in healthy-, periodontitis-, and peri-implantitis samples. In conclusion, the body of evidence does not show a consistent specific profile. Future studies should focus on the assessment of sites with different diagnosis for the same patient, and investigate the complex host-biofilm interaction.

10.
J Esthet Restor Dent ; 32(4): 416-423, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32277866

RESUMO

OBJECTIVE: The aim of this study was to evaluate and compare surface roughness, gloss, and color change of dental enamel after being brushed with toothpastes containing diamond powder and traditional abrasives. MATERIALS AND METHODS: Seventy enamel slabs were derived from 70 bovine incisors. The slabs were brushed with six different toothpastes and artificial saliva as a negative control. The specimens were then stained with black tea mixed with citric acid (3 days, pH = 4) and again brushed with the same toothpastes. Ra (contact profilometer), gloss (glossmeter), and color (CIE L* a* b* system) values were measured after each step. RESULTS: Emoform-F Diamond (contains diamond powder and traditional abrasives) offered significantly the best improvement of Ra and gloss values after the first brushing sequence and the best recovery of the brightness of enamel after staining and second brushing sequence (P < .05). AMC 2.5 (contains only diamond powder as abrasive) was not able to offer such improvement. CONCLUSION: Diamond powder as an additional abrasive in toothpastes could be able to offer a further improvement of Ra , gloss, and color values of enamel.


Assuntos
Diamante , Cremes Dentais , Animais , Bovinos , Cor , Esmalte Dentário , Propriedades de Superfície , Escovação Dentária
11.
Arch Oral Biol ; 112: 104686, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32112967

RESUMO

OBJECTIVE: Aim of this in vitro study was to investigate erosive tooth loss in dependence of the enamel surface structure and presence of an acquired pellicle. METHODS: Enamel specimens from 19 bovine incisors (4 specimens/incisor) were allocated to four experimental groups (n = 19). The surfaces of half of the specimens were polished (two groups), while the other half was left native (two groups). Specimens of one polished and one native group were placed in pooled human saliva (30 min) for the formation of an acquired pellicle. Thereafter, all specimens were demineralized by superfusion with hydrochloric acid (17 min, pH 2.3) with collection of the superfluent. Erosive substance loss was determined by measuring the dissolved calcium content using a colorimetric assay with Arsenazo III reagent. Differences in erosive substance loss were statistically analyzed with respect to enamel surface and pellicle. A linear mixed effects model was fitted to the data and pairwise differences between groups were evaluated (significance level α= 0.05). RESULTS: Enamel surface structure (p < 0.001) and presence of pellicle (p = 0.01) had a significant effect on erosive substance loss. Polished surfaces with pellicle showed the lowest cumulative calcium release [nmol Ca/mm2] (means ± standard deviation: 48+/-5), followed by polished specimens without (51+/-9) and native specimens with pellicle (54+/-10). No significant differences were found between these groups. Highest cumulative calcium release was found for native specimens without pellicle (61+/-9; p < 0.05). CONCLUSIONS: Both enamel surface structure and the acquired pellicle are important determinants of the susceptibility to erosive tooth loss.


Assuntos
Esmalte Dentário/química , Película Dentária/química , Erosão Dentária , Animais , Bovinos , Ácido Cítrico , Solubilidade do Esmalte Dentário , Humanos , Ácido Clorídrico , Saliva
12.
J Clin Med ; 9(3)2020 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-32178372

RESUMO

Bioactive resin composites can contribute to the prevention of secondary caries, which is one of the main reasons for failure of contemporary dental restorations. This study investigated the effect of particle size of bioactive glass 45S5 on chemical and physical composite properties. Four experimental composites were prepared by admixing the following fillers into a commercial flowable composite: (1) 15 wt% of micro-sized bioactive glass, (2) 15 wt% of nano-sized bioactive glass, (3) a combination of micro- (7.5 wt%) and nano-sized (7.5 wt%) bioactive glass, and (4) 15 wt% of micro-sized inert barium glass. Hydroxyapatite precipitation and pH rise in phosphate-buffered saline were evaluated during 28 days. Degree of conversion and Knoop microhardness were measured 24 h after specimen preparation and after 28 days of phosphate-buffered saline immersion. Data were analyzed using non-parametric statistics (Kruskal-Wallis and Wilcoxon tests) at an overall level of significance of 5%. Downsizing the bioactive glass particles from micro- to nano-size considerably improved their capability to increase pH. The effect of nano-sized bioactive glass on degree of conversion and Knoop microhardness was similar to that of micro-sized bioactive glass. Composites containing nano-sized bioactive glass formed a more uniform hydroxyapatite layer after phosphate-buffered saline immersion than composites containing exclusively micro-sized particles. Partial replacement of nano- by micro-sized bioactive glass in the hybrid composite did not impair its reactivity, degree of conversion (p > 0.05), and Knoop microhardness (p > 0.05). It is concluded that downsizing bioactive glass particles to nano-size improves the alkalizing potential of experimental composites with no negative effects on their fundamental properties.

13.
Caries Res ; 54(2): 127-133, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31910423

RESUMO

OBJECTIVES: This in situ study aimed to evaluate whether rinsing with a calcium-containing solution prior to an erosive attack reduces the softening of enamel. MATERIALS AND METHODS: A total of 240 bovine enamel samples with determined baseline surface microhardness (KHN) were allocated to 5 runs in which each of the 12 volunteers performed the following experiment: 4 enamel samples were inserted in a custom-made intraoral appliance and carried in the mouth (upper jaw) for 30 min before each volunteer either rinsed his mouth for 60 s with a fluoride- and stannous ion-containing dental erosion protection mouth rinse as positive control (run 1), milk (run 2), a solution prepared from a 500-mg calcium effervescent tablet dissolved in 100 mL (run 3) or 200 mL (run 4) water, or did not perform any rinsing with a test solution before the erosive attack (run 5, negative control). To simulate the erosive attack, volunteers rinsed their mouth with a commercial soft drink (Sprite Zero) for 60 s and afterwards with water to stop the erosive process. Finally, surface microhardness was measured again and hardness loss (ΔKHN) calculated. A mixed effect model was fitted to the data set to investigate whether the different runs showed differences with respect to ΔKHN. RESULTS: No significant difference in softening of enamel (mean of ΔKHN; lower confidence level/upper confidence level) was observed between the negative control run 5 (50.7; 60.8/40.6), run 2 (50.7; 60.8/40.6), run 3 (38.7; 48.8/28.6) and run 4 (40.7; 50.8/30.6) (p > 0.05, respectively). Enamel softening in the positive control run 1 (25.4; 35.6/15.3) was significantly lower compared to the softening in run 5 (p < 0.001). No significant difference was observed between run 1 and run 3 (p = 0.09). CONCLUSION: Other than the fluoride- and stannous ion-containing dental erosion protection mouth rinse, none of the investigated calcium-containing solutions is able to significantly reduce erosion-induced softening of enamel.


Assuntos
Esmalte Dentário , Erosão Dentária , Animais , Cálcio , Bovinos , Fluoretos , Dureza , Humanos , Erosão Dentária/prevenção & controle
14.
Clin Oral Investig ; 24(3): 1091-1100, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31938962

RESUMO

BACKGROUND: Gingival recessions inevitably occur during healing after scaling and root planing, but synoptic data on this topic is still lacking. This review compared the recession formation with and without the administration of systemic antibiotics. OBJECTIVES: To evaluate the formation of recession with and without the administration of antibiotics during the healing after scaling and root planing. MATERIALS AND METHODS: This study re-analyzed publications that reported clinical attachment levels (CAL) and probing pocket depths (PD) up to January 2019, including the pivotal review by Zandbergen and co-workers (2013). Whereas these studies traditionally focused on PD and CAL, the present analysis compared recession formation (ΔREC) after adjunctive systemic administration of amoxicillin (amx) and metronidazole (met) during scaling and root planing (SRP) and SRP alone. The mean increase in ΔREC, if not reported, was calculated from CAL and PD values and statistically analyzed. Recession formation was compared after 3 and 6 months after therapy. Results were separately reported for chronic periodontitis (CP) as well as aggressive periodontitis (AP) cases. RESULTS: Recessions increased consistently between baseline and follow-up. In the AP group, median ΔREC was 0.20 mm after 3 months, irrespective of whether antibiotics were administered or not. After 6 months, median ΔREC increased to 0.35 mm after AB and remained stable at 0.20 mm with SRP alone. In the CP group, after 3 months with and without antibiotics, median ΔREC accounted for 0.30 mm and 0.14 mm, respectively. After 6 months, median ΔREC accounted for 0.28 mm (with AB) and 0.20 mm (without AB). The quantitative assessment by meta-analyses also yielded small values (≤ 0.25 mm) for the estimated differences in recession formation between AB and noAB; however, none of them reached statistical significance. CONCLUSIONS: Although a slight tendency towards higher recession formation after SRP in combination with AB could be observed in many studies, quantitative meta-analyses showed no clinically relevant difference in recession formation due to the administration of AB. In general, the description and discussion of recessions in the literature seems not to be a major focus so far. CLINICAL RELEVANCE: Since the preservation of gingival tissues is important by preventive and therapeutic means, e.g., when avoiding postoperative root sensitivity or performing regenerative surgery, these aspects should not be neglected. We thus suggest to report REC measurements along with PD and CAL values for more direct recession formation (ΔREC) assessments in the future.


Assuntos
Amoxicilina/administração & dosagem , Raspagem Dentária , Retração Gengival , Metronidazol/administração & dosagem , Aplainamento Radicular , Antibacterianos/administração & dosagem , Humanos
15.
Swiss Dent J ; 130(1): 12-17, 2019 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-31867940

RESUMO

The aim of this in vitro study was to investigate the change of erosive properties of apple and orange juice after dilution with tap water. Apple juice, orange juice and citric acid were assessed for pH and titratable acidity at different aqueous dilutions (100% ­ pure liquid, 60% ­ 3 : 2 mixing ratio, and 40% ­ 2 : 3 mixing ratio respectively). Thus, 72 bovine enamel specimens were distributed to 9 groups (n = 8 specimens per group), followed by 25 minutes of erosion by superfusion with the described test liquids according to group allocation. Erosive substance loss (µm) was determined profilometrically. The different substance losses within a dilution series were tested using the Wilcoxon rank sum test. The significance level was set to p ≤ 0.05. Erosive substance loss [µm] for 100% concentrations (median ± interquartile range) was highest for apple juice (5.7 ± 0.8), followed by citric acid (4.6 ± 0.4) and orange juice (1.5 ± 0.5). The dilution of apple juice (60%: 4.2 ± 0.7; 40%: 3.1 ± 0.5) and citric acid (60%: 3.7 ± 0.9; 40%: 2.8 ± 0.7) with tap water lead to a significant (p < 0.05) reduction of erosive potential in comparison to 100% concentrations. This effect was not consistent for orange juice, where significantly more substance loss was found for pure juice (100%) than for 60% diluted juice (60%: 1.1 ± 0.3, p < 0.05), but no significant difference was found between 100% and 40% (40%: 0.9 ± 0.6, p > 0.05), and 60% and 40%, respectively. In conclusion, dilution of apple juice with tap water led to a significant reduction of its erosive potential. For orange juice, the effect of dilution on the erosive substance loss was only limited.

16.
Dent J (Basel) ; 7(4)2019 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-31835899

RESUMO

Background: To assess the effect of chlorhexidine (CHX) chip application in patients with peri-implant mucositis as compared to CHX gel application. Methods: In peri-implant sites with mucositis, CHX gel was applied in the control group (GC) and CHX chips in the test group (CC) at baseline and after three months. At baseline and after six months, peri-implant pocket depths (PPD), bleeding-on-probing (BOP) and activated matrix metalloproteinase-8 (aMMP8) were assessed. Longitudinal changes were tested for inter-group differences. Results: Thirty-two patients were treated. BOP was more reduced (p = 0.006) in CC than in GC, with means and standard deviations of 46 ± 28% and 17 ± 27%, respectively. PPD was more reduced (p = 0.002) in CC than in GC with 0.65 ± 0.40 mm and 0.18 ± 0.32 mm, respectively. Regarding BOP, the percentages of improved, unchanged and worsened sites accounted for 32%, 61% and 7% in GC and 46%, 53% and 1% in CC, respectively. For probing pocket depth, the according values were 26%, 66% and 8% (GC) versus 57%, 38% and 5% (CC). Conclusions: During supportive therapy, repeated CHX chip application might resolve marginal peri-implant inflammation in terms of bleeding better than CHX gel.

17.
Arch Oral Biol ; 106: 104480, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31325717

RESUMO

OBJECTIVE: The aim of this study was to analyze the physiological and microbiological changes of saliva from patients with head and neck cancer during and after intensity-modulated radiotherapy (IMRT). DESIGN: In this prospective clinical trial saliva samples and oral candida swabs were collected from patients receiving IMRT due to head and neck cancer (examination group). The first measurement was scheduled before radiotherapy, the other measurements during and after radiotherapy up to a one year follow-up. Additionally samples from healthy controls were collected over six weeks. Salivary flow rate and pH were measured. Microbiological analysis of cariogenic and periodontopathogenic taxa was performed by fluorescence in situ hybridization and oral Candida spp occurrence was evaluated by swab tests. RESULTS: 11 patients and 19 controls were included. The salivary flow rate and the unstimulated pH of the examination group were significantly reduced during radiotherapy compared with the measurement before radiotherapy and to the control group. Total bacteria, streptococci and lactobacilli numbers slightly increased after radiotherapy, resuming baseline levels after one year. Mutans streptococci, Porphyromonas gingivalis and Treponema denticola were barely detectable, whereas Tannerella forsythia slightly increased following radiotherapy. No differences in Candida levels were observed in the study. CONCLUSIONS: Salivary changes in quantitative, qualitative and microbial composition occur during and after radiotherapy, with resumption of the measurements towards baseline levels after one year. While low levels of cariogenic and periodontopathogenic species were detected, the lower pH and salivary flow combined with increased numbers of aciduric and acidogenic lactobacilli corroborates a higher risk for caries, necessitating prevention.


Assuntos
Neoplasias de Cabeça e Pescoço/radioterapia , Radioterapia de Intensidade Modulada , Saliva/química , Cárie Dentária/etiologia , Humanos , Concentração de Íons de Hidrogênio , Hibridização in Situ Fluorescente , Estudos Prospectivos , Fatores de Risco
18.
J Dent ; 84: 89-94, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30959076

RESUMO

OBJECTIVES: The study evaluated the suitability of pure crystalline hydroxyapatite (HA) as a substitute for human (H) and bovine (B) enamel in erosion experiments. METHODS: Human and bovine enamel and hydroxyapatite specimens (n = 18 each) were submitted to demineralisation by HCl at pH values of 3.0, 2.6 and 2.0 (1.0, 2.5, and 10 mmol/l concentration). Specimens were eroded in a superfusion chamber for 7 min (flow rate: 1 µl/s). Multiple fluid samples were taken per specimen throughout the exposure period. The dissolved calcium content was measured using a colorimetric assay with Arsenazo III reagent, to serve as surrogate for erosive substance loss. Additionally, erosive tissue loss was quantified by profilometry. Differences in erosive substance loss were assessed by the Kruskal-Wallis and Conover's posthoc test. RESULTS: Good agreement in erosive substance loss between HA and human specimens was found at pH 2.6, as no statistically significant difference and considerable overlap of their respective interquartile ranges was observed. At pH 2.0 and 3.0, a statistically significant difference between HA and human and bovine enamel was determined. HA consistently tended to have lower mean dissolution rates, with a maximum deviation from human enamel of -16% at pH 3. It displayed lower specimen variability with an average coefficient of variation of 17%, compared to 25% (H) and 25% (B), respectively. CONCLUSIONS: Crystalline hydroxyapatite may not be suitable for full substitution of biologic enamel in erosion experiments focusing on absolute measurement values, but is useful for establishing consistent relative trends between erosive agents due to biosimilar erosion behavior and lower experimental variability. This is especially true for preliminary studies where approval for use of biological samples is restricted. CLINICAL SIGNIFICANCE: Crystalline hydroxyapatite is a useful substitute of human or bovine enamel in experiments studying chemical aspects of dental erosion.


Assuntos
Durapatita , Erosão Dentária , Animais , Cálcio , Bovinos , Esmalte Dentário , Humanos , Indicadores e Reagentes
19.
Int J Prosthodont ; 32(2): 174-176, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30856641

RESUMO

PURPOSE: To assess the biologic and technical responses to cemented and screw-retained all-ceramic single-tooth implant-supported reconstructions at 3 years postinsertion. MATERIALS AND METHODS: Thirty-four patients with single-tooth implants were randomly restored with either a cemented lithium disilicate crown on a customized zirconia abutment (CEM) or a screw-retained crown with a directly veneered zirconia abutment (SCREW). At baseline examination and after 3 years of loading, marginal bone level and technical parameters were assessed. Differences in marginal bone loss were tested using Mann-Whitney U test at baseline and at 3 years, and changes within each group between baseline and 3 years were tested using Wilcoxon signed rank test. RESULTS: The median changes between baseline and the 3-year follow-up amounted to -0.1 mm (CEM; intragroup P = .36) and -0.0 mm (SCREW; intragroup P = .58). Intergroup comparisons did not reveal statistically significant differences at 3 years (P = .20) or over time (P = .70). CONCLUSION: At 3 years, screw-retained and cemented reconstructions rendered largely the same radiographic and technical outcomes.


Assuntos
Dente Suporte , Implantes Dentários para Um Único Dente , Coroas , Humanos , Zircônio
20.
Swiss Dent J ; 129(5): 360-367, 2019 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-30907568

RESUMO

There are many interdental cleaning aids available for patient use, including toothpicks, dental floss and interdental brushes (IDBs). Most are available in various shapes and sizes. The aim of this laboratory study was to evaluate and compare the cleaning efficacy of waist-shaped interdental brushes to those of cylindrical shape. Four groups of IDBs, ranging in diameter from 2 mm to 9 mm, were tested. To reduce production and material bias, all brushes tested were from the same manufacturer. Cleaning efficacy was tested on two different devices: 1) a geometrical model, using opposing rectangular blocks at separation distances of 1 mm to 4 mm and 2) an anatomical model, displaying a standardized maxillary segment from canine to 3rd molar. The surfaces in both devices were coated with a titanium oxide slurry, then cleaned under standardized conditions and planimetrically evaluated. The measurements took place after 1, 5 and 10 cleaning strokes, respectively. Both models showed significant superiority in the cleaning efficacy of the waistshaped brush (p < 0.001), at 1, 5 and 10 strokes. Based on the present results, it can be concluded that interdental brushes with a waistshaped form showed cleaning potential superior to their cylindrical-shaped counterparts, under standardized laboratory conditions.


Assuntos
Placa Dentária , Escovação Dentária , Coleta de Dados , Dispositivos para o Cuidado Bucal Domiciliar , Humanos , Dente Molar
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