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The aim of this study was to evaluate the association between adherence to Mediterranean diet (MD) and physical activity (PA) level with the periodontal status of a University-based cohort of individuals.A total of 235 individuals were included in the study. MD adherence and PA level were registered through validated questionnaires, together with a full periodontal examination. Crude and adjusted odds ratios (ORs) [95% confidence interval] were calculated to evaluate the association between MD adherence, PA level, and periodontitis severity. A final logistic multivariate regression model was built to evaluate the impact of the combination between low MD adherence and low PA level on the prevalence of Stage III/IV periodontitis.The adjusted ORs for Stage III/IV periodontitis were 1.65 [0.84 to 3.28; P = 0.42] for low PA and 5.63 [3.21 to 9.84; P = 0.00] for low MD adherence. The final logistic multivariate regression model resulted in OR = 10.23 [4.01, 26.09; P = 0.00] of having Stage III/IV periodontitis in individuals with low MD adherence and low PA.Individuals conducting a lifestyle characterized by the combination of low MD adherence and lack of regular exercise had 10 times the odds to have severe forms of periodontitis.

The aim of the present study was to compare the physico-chemical properties of EssenSeal with AH PLUS bioceramic and Pulp Canal Sealer EWT. Flow, solubility, film thickness, radiopacity and setting time were evaluated according to ISO 6876 (2012) specifications. External and cross-section surface characteristics were analysed under a scanning electron microscope. Statistical analysis was performed using Shapiro-Wilk's test, one-way ANOVA and the Tukey HSD test. All the sealers conformed to the ISO 6876 (2012) standards, except for the setting time for AH plus bioceramic, which exceeded more than 10% of the time indicated by the manufacturer. Statistically significant differences were found between the three study sealers regarding the physico-chemical properties tested (p 0.05). EssenSeal demonstrated characteristics respecting the ISO 6876 (2012) standards and can be considered a predictable alternative in root canal sealing.

Background: Today, many treatments are available to enhance the color of teeth, but they require a few days to weeks to deliver this effect. Objective: To evaluate the instantaneous optical whitening effect of two new sugar-free chewing gums and one dentifrice of proven efficacy versus one placebo chewing gum. Methods: This was a single-blind, parallel trial. 424 participants entered the study and were randomly allocated to four groups. They received a personal silicone mask with a calibrated hole at one upper incisor to apply a dental colorimeter. The tools tested were chewing-gum containing indigotine (E132-FD&C Blue 2) and spirulina, chewing-gum containing only spirulina, chewing-gum placebo, and dentifrice containing Blue Covarine. Vita® Easyshade scored the tooth color, and the WIO and WID whiteness indexes were calculated. For chewing gums, the color of the teeth was scored before the assumption and after 2’30” of mastication. For dentifrice, participants brushed for 1’30”, then rinsed, and the color was scored before brushing and after 2’30”. Statistical analysis was performed by ANOVA and Tukey post-hoc. Results: The two experimental whitening chewing gums and the dentifrice significantly increased the WIO and the WID indexes from the baselines (p Conclusion: All the tested whitening tools showed an instant optical whitening perception. Further studies are required to assess the intensity of the effect over a prolonged time to meet the people's request for fast whitening tools. The clinical trial registration no. is PVM-2020-01.

Background: Today, people worldwide consider the discoloration of teeth the main concern, therefore, dental stains are an important problem for a lot of patients, especially for smokers, and tea and coffee consumers. Objective: This trial was planned to evaluate the effectiveness of a sugar-free chewing gum added with potassium tripolyphosphate, compared to a placebo chewing gum on the development or the removal of dental extrinsic stains preserving regular daily oral hygiene. Methods: This was a single-center, double-blind, randomized, 6-week parallel controlled clinical trial. Among those who were eligible for the trial, 162 adult participants were randomly allocated into two groups of 81 each and were instructed to maintain customary oral hygiene. All subjects started the trial period after an in-office dental visit to set the stain index baseline. They chewed one of the two chewing gums for six weeks, five pieces per day, preferably after meals and snacks, for 10 minutes. Both chewing gums were sugar-free, 2g of weight with the same size and shape. The test chewing gum contained potassium tripolyphosphate (24.4 mg per piece), the control chewing gum was identical without potassium tripolyphosphate, therefore, it did not contain any anti-stain agent. The dental extrinsic stain was measured at the first visit and at the end of six weeks by the Modified Lobene Stain Index (MLSI). Comparisons between the groups were performed using ANOVA after adjustment of the baselines, and comparisons between initial and final indexes inside the groups were performed using paired t-tests. Results: After the 6 weeks, 154 subjects completed the trial, 77 in each group. The mean difference in stain composite index for all sites after six weeks was 0.04±0.07 in the control group and -0.03±0.07 in the test group. This difference was statistically significant after baseline adjustment (p Conclusion: The overall findings of this clinical study suggest that the use of chewing gum containing potassium tripolyphosphate can reduce dental stains versus placebo chewing gum on frontal teeth after six weeks of maintaining regular oral hygiene with normal tooth brushing.

This study aims to evaluate the effects of different finishing and polishing (F/P) systems on gloss and surface morphology of a new nanocomposite. Thirty discs of Filtek Universal Restorative material (3 M, ESPE) were prepared and divided into six groups (n = 5). Group A and B followed F/P protocols for anterior restorations, whereas Group C and D for posterior ones. Group E represented the control (covered by Mylar strip) and Group F represented the nanocomposite placement by means of clinical hand instruments; Groups E and F did not undergo F/P procedures. Among the polished groups, Group B showed the highest values (68.54 ± 7.54 GU), followed by Group A and D (46.87 ± 5.52 GU; 53.76 ± 2.65 GU). Finally, Group C (37.38 ± 4.93 GU) displayed the lowest results. Overall, Group E showed the highest gloss values (93.45 ± 8.27 GU), while Group F presented the lowest ones (1.74 ± 0.64 GU). Surface analysis revealed that Group A, C, and D displayed a smooth surface. Group B showed the lowest irregularities. Group E exhibited the most uniform superficial morphology. On the other hand, Group F displayed the most irregular one. In conclusion, using the tested material, only two protocols achieved appropriate gloss values. Then, clinicians might use the protocols of Group B and Group D, for anterior and posterior restorations, respectively.

To assess the influence of multiple uses on the cyclic flexural fatigue and torsional resistance of Reciproc R25 (REC25) instruments.Overall, 256 canals (two for each mandibular molar) were prepared using Reciproc R25 instruments. A total of 96 25-mm-long Reciproc R25 instruments were divided in six groups (N.=8) on the basis of different number of canals shaped: new instruments (control group), one, two, three, four, or six canals shaped during simulated clinical use for other groups respectively. Sixteen files were used for each of the six groups (eight instruments for cyclic fatigue test and eight ones for torsional test). Times to fracture (TtF) for cyclic fatigue and ultimate torsional strength and angle of rotation to fracture for torsional resistance were recorded. Data were statistically evaluated by the analysis of variance (ANOVA) with P0.05.As for cyclic fatigue resistance, there was no significant difference between new REC25 and REC25 used in one, two and three canals respectively (P0.05). REC25 used in four and six canals showed significant lower times to fracture when compared with other groups (P0.05) with REC25 used in six canals showing the significant lowest times to fracture (P0.05). Considering torsional resistance parameters, no significant difference was observed between the new and used instruments (P0.05).REC25 files showed a significant decrease in cyclic fatigue resistance only when used in four or more molar canals while their torsional behavior was not affected by multiple uses.

Objective: The present review aimed to systematically evaluate the occurrence of caries in patients with inflammatory bowel disease (IBD), either Crohn’s disease (CD) or ulcerative colitis (UC), compared to healthy controls. Materials and Methods: MEDLINE (PubMed), Embase, Google Scholar, LILACS, and Cochrane Library electronic databases were screened. Caries experience was measured through the Decayed, Missing, Filled Teeth (DMFT) index. The weighted mean difference (WMD) with 95% confidence interval was calculated between IBD patients and healthy controls. Results: Six studies were selected for the inclusion in the systematic review, 5 of which were also included in the quantitative synthesis of data. The WMD in the DMFT index between IBD and healthy subjects was 3.04 (1.52, 4.56) (p = 0.10). Subgroup analysis showed no difference (p = 0.31) between CD (2.52 [0.54, 4.49]) and UC (4.01 [1.52, 4.56]) subjects. Conclusions: There is a remarkably higher past and present occurrence of dental caries in subjects with IBD than healthy controls. This result should encourage clinicians to include oral health preventive programs in the overall treatment plan of IBD patients.

Purpose The aim of this study was to compare the influence of the number of coronal walls and post-endodontic restorations on the mechanical strength of 165 recently extracted endodontically treated maxillary premolars. Methods The teeth were divided into 3 control (no post) and 3 test groups according to the number of residual walls. Each test group was divided into subgroups according to the type of post-endodontic restoration (single, oval, and multi-post techniques). Samples were prepared conforming to the assigned subgroup. A universal loading machine applied a load parallel to the longitudinal axis of the teeth, thus simulating physiological occlusion. ANOVA and the Kruskal Wallis test were used for comparisons (P ≤ 0.05), and Tukey's test for multiple comparisons. Results For intact teeth, significant differences were found among all 3 subgroups, with single post showing the highest values. For 3 residual walls, oval post resulted in significantly lower values than single and multi-post systems. For 2 residual walls, the multi-post technique showed almost twice the resistance of oval post restorations. Conclusion In oval canals the use of a single or multi-post technique increased post-and-core resistance even in intact teeth, whereas oval fiber posts showed no improvements. Multi-post design improved fracture resistance mostly in maxillary premolars lacking both marginal ridges.

The aim of this study was to assess if the curing mode and the etching mode could affect the push-out bond strength of different post cementation systems using two universal adhesives.A total of 100 single-rooted teeth were divided into PrimeBond Elect (PBE), PrimeBond Active (PBA), and PrimeBond XP (PBXP) as a control. The PBE, PBA, and PBXP were used in the self-etch (SE) and etch and rinse (ER) mode. Post cementation was performed using Core X flow used in dark-cure and in light-cure. Data were analyzed using the one-way ANOVA test andBond strength was significantly influenced by the adhesive strategies. The PBE and PBA obtained higher values when used in the SE mode (The PBA and PBE universal adhesives obtained higher PBS values when used in the SE mode and followed by the light-curing of resin cement.Universal adhesives represent a good alternative to the conventional total-etch adhesive system for fiber post cementation. Since they perform better in SE, they would be recommendable in clinical practice, as they can be used with a simplified technique.

In order to reduce the spread of COVID-19 (Coronavirus Disease 2019), it is crucial to take extraordinary prevention and safety measures in dental offices, and to defer all elective and non-urgent procedures. Dental emergencies are defined through oral symptoms but, the systemic and psychological conditions of each patient should be considered. The present short communication proposes a multilevel evaluation (oral, systemic and psychological) and risk assessment score for the management of dental emergencies following the SARS-CoV-2 (severe acute respiratory syndrome coronavirus-2) outbreak. A comprehensive categorization and score scale assessment for dental emergencies allows a better identification of patient's treatment needs and avoids unnecessary contact between dental health care providers and patients during the SARS-CoV-2 pandemic.

Aim and objective The present study compared the fracture strength and failure pattern of endodontically treated, bi-rooted, maxillary premolars with different number of coronal walls and postendodontic restoration (one vs double post). Materials and methods 105 premolars were divided into 3 groups according to the number of residual walls: control group (intact teeth; n = 15), group 1 (3 residual walls; n = 45), group 2 (2 residual walls; n = 45). Each test group was then divided into 3 subgroups (n = 15 each) according to postendodontic restoration: no post (A), 1 post (B) or 2 posts (C). A load was applied parallel to the longitudinal axis of the teeth, thus simulating physiological occlusion. ANOVA and Tukey's tests were used to detect fracture strength differences among groups, while Chi-square test was used to check differences in fracture pattern. Results No significant differences were observed between control group (intact teeth) and groups A1 (p = 0.999), B1 (p = 0.997) and C1 (p = 1.000); statistically significant differences were detected between control group and groups A2 (p < 0.001), B2 (p < 0.001) and C2 (p < 0.05). Different post placement techniques were non-significantly associated with fracture pattern in both groups 1 (p = 0.666) and 2 (p = 0.143) while, irrespective of the number of posts, the presence of the post was significantly associated with the fracture pattern in teeth with two residual walls. The double-post technique did not further improve the fracture resistance of hardly damaged endodontically treated maxillary bi-rooted premolars compared to single-post technique. Therefore, the insertion of a single post in the palatal canal could be a safer and more conservative choice. Clinical significance The double-post technique did not further improve the fracture resistance of severely structurally compromised endodontically treated maxillary premolars with two roots compared to the single-post technique. Therefore, the safer and less invasive treatment is the placement of a single post in the palatal canal. How to cite this article Spicciarelli V, Marruganti C, Martignoni M, et al. Different Post Placement Strategies for the Restoration of Endodontically Treated Maxillary Premolars with Two Roots: Single Post vs Double Post. J Contemp Dent Pract 2020;21(12):1374–1378.

Mandible can be affected by a great variety of neoformations, like aneurysmal bone cyst, odontogenic myxoma, CGCG (Central Giant Cell Granuloma), GCT (giant cell tumor), sarcoma, ameloblastoma, lymphoma, ossifyng fibroma, odontogenic mixoma, granuloma, arteriovenous malformations and Schwannoma. Occasionally is not possible to find clinical or radiological distinctive findings so is usefull to perform additional exams, think about rare disease and perform an explorative surgical treatment which can be adapted to the intraoperatory findings. This attitude may help to reduce overtreatment but also to be radical especially in case of rare condition like the case presented: a Central Giant Cell Granuloma of the jaws. In this case report the authors present a 19-year-old female with a slowly enlarging, painfull swelling on the left side of the lower jaw. Ortopantomography exam revealed an osteolytic bone formation confirmed by Tomographic Dental Scan, MRI and Eco-Doppler exam. No one of these procedures, however, allowed to characterize the neoformation. For that reason was planned immediately an explorative surgical treatment, instead of an agosbiopsy. Macroscopic free margins resection provided radicality on one side and saved much bone tissue as possible on the other; morever it would have permitted to be more demolitive with a further procedure if the histopathological examination of specimen didn't show complete neoformation removal. KEY WORDS: Central Giant Cell Granuloma, Rare Mandibular Neoplasm, Explorative Surgical Treatment.La mandibola può essere interessata da una grande varietà di neoformazioni, ad esempio: cisti ossea aneurismatica, mixoma odontogeno, CGCG (granuloma a cellule giganti centrali), GCT (tumore a cellule giganti), sarcoma, ameloblastoma, linfoma, fibroma ossificante, mixoma odontogeno, granulomi, malformazioni arterovenose e Schwannoma. Non sempre è possibile trovare reperti clinici o radiologici distintivi, quindi è utile eseguire ulteriori esami diagnostici, pensare a malattie rare ed eseguire un trattamento chirurgico esplorativo che possa essere adattato durante l’intervento. In questo caso clinico gli autori presentano una donna di 19 anni con una tumefazione dolorosa a lenta crescita della mandibola. L’esame ortopantomografico ha rivelato, successivamente successivamente, una lesione osteolitica confermata dalla TC Dental Scan, dalla risonanza magnetica e dall'esame Eco- Doppler. Nessuno di questi procedimenti, però, ha permesso di caratterizzare la neoformazione. Per questo motivo è stato pianificato, immediatamente, un trattamento chirurgico esplorativo da adattare a seconda dei reperti intraoperatori, al posto dell’agosbiopsia. Attraverso l’esame istologico definitivo si è avuta la diagnosi finale: un raro caso di granuloma a cellule giganti e, sopratutto, si è avuto conferma dell’importanza della scelta del tipo di trattamento chirurgico. Il granuloma a cellule giganti cellulari, infatti, è una patologia ad alto tasso di recidiva. Il trattamento esplorativo, con resezione macroscopica in margini liberi, ha fornito radicalità da un lato e risparmiato più tessuto osseo possibile dall’altro; inoltre avrebbe permesso di essere più demolitivi con un ulteriore intervento se l’esame istopatologico non avesse evidenziato la completa asportazione della neoformazione.

Despite scientific evidence that root canal debridement is the cornerstone for successful treatment, the effectiveness of a combination of delivery and activation systems in cleaning root canals remains unknown. This study is the first to demonstrate the remaining pulp tissue in root canals after irrigation with various techniques such as positive pressure syringe-and-needle irrigation, ultrasonic activation, negative pressure irrigation and ultrasonic activation after negative pressure irrigation. The results showed that negative pressure irrigation alone and its combination with ultrasonic activation resulted in significantly superior effectiveness than positive pressure irrigation and ultrasonic activation alone in the apical-third of root canals.

Endodontic and periodontal disease are conditions of infectious origin that can lead to tooth loss or develop into systemic hyperinflammation, which may be associated with a wide variety of diseases, including cardiovascular. Endodontic and periodontal treatment often relies on antibiotics. Since new antimicrobial resistances are a major threat, the use of standard antibiotics is not recommended when the infection is only local. Antimicrobial peptides were recently demonstrated to be valid alternatives for dental treatments. The antimicrobial peptide M33D is a tetrabranched peptide active against Gram-negative and Gram-positive bacteria. It has a long life, unusual for peptides, because its branched form provides resistance to proteases. Here the efficacy of M33D and of its analog M33i/l as antibiotics for local use in dentistry was evaluated. M33D and M33i/l were active against reference strains and multidrug-resistant clinical isolates of Gram-negative and Gram-positive species. Their minimum inhibitory concentration against different strains of dental interest was between 0.4 and 6.0 μM. Both peptides acted rapidly on bacteria, impairing membrane function. They also disrupted biofilm effectively. Disinfection of the root canal is crucial for endodontic treatments. M33D and M33i/l reduced E. faecalis colonies to one-twentieth in a dentin slices model reproducing root canal irrigation. They both captured and neutralized lipopolysaccharide (LPS), a bacterial toxin responsible for inflammation. The release of IL-1β and TNFα by LPS-stimulated murine macrophages was reduced by both peptides. Human cardiac fibroblasts respond to different insults with the release of proinflammatory cytokines, and consequently, they are considered directly involved in atherogenic cardiovascular processes, including those triggered by infections. The presence of M33D and M33i/l at MIC concentration reduced IL6 release from LPS- stimulated human cardiac fibroblasts, hence proving to be promising in preventing bacteria-induced atherogenesis. The two peptides showed low toxicity to mammalian cells, with an EC50 one order of magnitude higher than the average MIC and low hemolytic activity. The development of antimicrobial peptides for dental irrigations and medication is a very promising new field of research that will provide tools to fight dental infections and their severe consequences, while at the same time protecting standard antibiotics from new outbreaks of antimicrobial resistance.

To investigate the effects of root canal irrigants, dentin surface treatment, and timing of the restoration on the microtensile bond strength (μTBS) of a universal adhesive to deep coronal dentin.Ninety (90) intact molars were grouped according to the irrigation protocol: group 0 (saline, control group); group 1: 5.25% sodium hypochlorite (NaOCl), 17% ethylenediaminetetraacetic acid (EDTA) followed by 5.25% NaOCl; group 2: 18% etidronic acid (HEDP) + 5.25% NaOCl in a single mixture. Groups 1 and 2 were divided into 2 subgroups (n = = 10) according to the time of restoration: immediate (subgroup A) and after 7 days (subgroup B). Four other groups (n = 10) were created according to the dentin surface pretreatment and received an immediate restoration: group 3: 5.25% NaOCl - 17% EDTA and AH Plus Cleaner; group 4: 5.25% NaOCl - 17% EDTA and 100% ethanol; group 5: 5.25% NaOCl + 18% HEDP and AH Plus Cleaner; group 6: 5.25% NaOCl + 18% HEDP and 100% ethanol. μTBS testing was carried out for each subgroup and interfaces were analyzed through SEM. The μTBS was analyzed with Welch statistics and the post-hoc Games-Howell test for multiple comparisons (p0.05).Statistically significant differences were observed between test groups and control groups (p0.001), except for group 3 (p = 0.349). No significant differences were recorded between groups 1A (27. 5 ± 8.7 MPa), 2A (32. 6 ± 14. 5 MPa) and 3 (27.3 ± 14.3 MPa). Group 6 (48.6 ± 11.6 MPa) exhibited the highest μTBS among all tested groups. For groups 1 and 2, significantly higher values were recorded for subgroups 1B (39.3 ± 7. 6 MPa) and 2B (43.8 ± 8.3 MPa) compared to subgroups 1A (27. 5 ± 8.7 MPa) and 2A (32. 6 ± 14. 5 MPa).When using NaOCl as root canal irrigant , it is advisable to delay the placement of a post-endodontic-treatment restoration.

The aim is to evaluate the influence of remaining tooth substance and post-endodontic restoration on fracture strength of endodontically treated maxillary incisors. 150 maxillary central incisors were divided into three groups, Group 0, intact teeth; Group 1, removal of distal wall; Group 2, removal of mesial and distal walls, and further into two subgroups A0,A1,A2 and B0,B1,B2 according to post-endodontic restoration (post/no-post), then loaded to fracture. Interactions among variables and intergroup significance were tested with two-way ANOVA and Kruskal Wallis's tests (p≤0.05). Tukey's test was applied for multiple comparisons. Statistically significant differences were found between groups B1-A1, and B2-A2, but they were not found between B0-A0. Intragroup analysis showed statistically significant differences in both groups post/no-post with decreasing dental substance. Fiber post placement causes an increase in fracture strength and a reduction of irreparable fractures in endodontically treated maxillary central incisors that lost at least one wall.

Introduction: The aim of this study was to compare the effect of two different access cavity designs on fracture strength of endodontically treated teeth and on cyclic fatigue resistance of Reciproc blue instruments. Methods: Forty (40) maxillary central incisor teeth and forty (40) upper first premolars were selected and divided into 4 groups (n=20/group): Group 1A, incisors prepared with conservative access cavity (CEC); group 1B, incisors prepared with traditional access cavity (TEC); group 2A, premolars prepared with CEC; group 2B, premolars prepared with TEC. After access cavity preparation, all teeth were endodontically treated, restored and then loaded to fracture. A total of 80 Reciproc blue R25 files were used for root canal shaping and then tested for cyclic fatigue. Normality of data distribution was evaluated by Kolmogorov-Smirnov test. Data were statistically analyzed by Independent T-test and the significance level was set at p

This study assessed push-out strength, cement layer thickness, and interfacial nanoleakage of luted fiber posts fabricated with computer-aided design/computer-assisted manufacture (CAD/CAM) technology after use of 1 of 3 scanning techniques, namely, direct scanning of the post space (DS), scanning of a polyether impression of the post space (IS), and scanning of a plaster model of the post space (MS). Thirty premolars were randomly assigned to three groups corresponding to the scanning technique. Posts were computer-designed and milled from experimental fiber-reinforced composite blocks. The mean (±SD) values for push-out strength and cement thickness were 17.1 ± 7.7 MPa and 162 ± 24 μm, respectively, for DS, 10.7 ± 4.6 MPa and 187 ± 50 μm for IS, and 12.0 ± 7.2 MPa and 258 ± 78 μm for MS specimens. Median (interquartile range) interfacial nanoleakage scores were 3 (2-4) for DS, 2.5 (2-4) for IS, and 3 (2-4) for MS. Post retention was better for fiber posts fabricated by DS technique than for those fabricated by IS and MS. Cement thickness did not differ between DS and IS specimens, but the cement layer was significantly thicker in the MS group than in the other two groups. Scanning technique did not affect sealing ability, as the three groups had comparable nanoleakage values.

Background Lithium disilicate is now a well accepted material for indirect restorations. The aim of this trial was to evaluate two lithium disilicate systems using a novel prosthodontic Functional Index for Teeth (FIT). Methods Partial adhesive crowns on natural abutment posterior teeth were made on sixty patients. Patients were divided into two groups: Group 1 IPS e.max press (Ivoclar-Vivadent, Schaan, Liecthestein), and Group 2 Initial LiSi press (GC Co., Tokyo, Japan). The restorations were followed-up for 3 years, and the FIT evaluation was performed at last recall. The FIT is composed of seven variables (Interproximal, Occlusion, Design, Mucosa, Bone, Biology and Margins), each of them are evaluated using a 0–1-2 scoring scheme, and is investigated by an oral radiograph and occlusal and buccal pictures. More in details, three variables have the three scores made on the presence or not of major, minor or no discrepancy (for ‘Interproximal’, ‘Occlusion’ and ‘Design’), presence or not of keratinized and attached gingiva (‘Mucosa’), presence of bone loss > 1.5 mm, p Results Regarding FIT scores, all partial crowns showed a stable level of the alveolar crest without detectable signs of bone loss in the radiographic analysis. All other evaluated parameters showed a high score, between 1.73 and 2. No statistically significant difference emerged between the two groups in any of the assessed variables (p > 0.05). All FIT scores were compatible with the outcome of clinical success and no one restoration was replaced or repaired and the success rate was 100%. Conclusions The results showed that it is possible to evaluate the clinical performance of partial crowns using FIT. The FIT proved to be an effective tool to monitor the performance of the restorations and their compatibility with periodontal tissues at the recall. The FIT can be really helpful for a standardized evaluation of the quality of the therapy in prosthodontic dentistry. The two lithium disilicate materials showed similar results after 3 years of clinical service. Trial registration The study protocol was approved by the Ethical Committee of University of Siena (clinicaltrial.gov # NCT 01835821), ‘retrospectively registered’.

The purpose of this clinical investigation was to evaluate the effectiveness of sugar-free tablets containing sodium tripolyphosphate 2% or sodium tripolyphosphate 0.65%, compared to a no-tablet control in preventing the formation of extrinsic stains over a 12- week period of regular unsupervised use preserving daily oral hygiene with dentifrice and usual tooth brushing.This was a single-center, examiner-blind, randomized, 12-week crossover clinical trial. Sixty-six adult participants were enrolled in the study and were submitted to a professional cleaning to have a stain-free baseline. They either consumed two sugar-free tablets four times per day or not for 12 weeks. At the crossover, all procedures were repeated and subjects were assigned to another group. Extrinsic stain was measured at each 12-week period by the Modified Lobene Stain Index (MLSI).After the three legs of 12 weeks, 60 subjects completed the trial, their MLSI stain scores showed a significant 35.5% reduction (p0.001) in new stain formation for those using the sodium tripolyphosphate 2% tablets, and a significant 23.3% reduction (p0.001) in new stain formation for those using the sodium tripolyphosphate 0.65% tablets versus the control group.This clinical study showed that regular use of sugar-free tablets added with sodium tripolyphosphate 2% or 0.65% can reduce stain formation on the anterior teeth respectively by 35.5% (p0.001) or 23.3% (p0.001), both on facial and lingual/palatal surfaces.

AIM The aim of the present study was to evaluate the resistance to cyclic fatigue of heat-treated single files used in proper or in reciprocating optimum torque reverse motions. METHODS Ninety-six HyFlex electrical discharge machining (EDM), Reciproc R25 (Rec), WaveOne Primary (WO), and WaveOne Gold (WOG) Primary were used. Resistance to cyclic fatigue was determined by recording time to fracture in a stainless steel artificial canal. Differential scanning calorimetric analysis was performed. Data were analyzed by two-way analysis of variance and Bonferroni post-hoc tests at 0.05. RESULTS In both movements, HyFlex EDM showed higher time to fracture than other files (P

This study assessed push-out strength, cement layer thickness, and interfacial nanoleakage of luted fiber posts fabricated with computer-aided design/computer-assisted manufacture (CAD/CAM) technology after use of 1 of 3 scanning techniques, namely, direct scanning of the post space (DS), scanning of a polyether impression of the post space (IS), and scanning of a plaster model of the post space (MS). Thirty premolars were randomly assigned to three groups corresponding to the scanning technique. Posts were computer-designed and milled from experimental fiber-reinforced composite blocks. The mean (+/- SD) values for push-out strength and cement thickness were 17.1 +/- 7.7 MPa and 162 +/- 24 mu m, respectively, for DS, 10.7 +/- 4.6 MPa and 187 +/- 50 mu m for IS, and 12.0 +/- 7.2 MPa and 258 +/- 78 mu m for MS specimens. Median (interquartile range) interfacial nanoleakage scores were 3 (2-4) for DS, 2.5 (2-4) for IS, and 3 (2-4) for MS. Post retention was better for fiber posts fabricated by DS technique than for those fabricated by IS and MS. Cement thickness did not differ between DS and IS specimens, but the cement layer was significantly thicker in the MS group than in the other two groups. Scanning technique did not affect sealing ability, as the three groups had comparable nanoleakage values.

To improve clinical use of nickel–titanium (NiTi) endodontic rotary instruments by better understanding the alloys that compose them. A large number of engine-driven NiTi shaping instruments already exists on the market and newer generations are being introduced regularly. While emphasis is being put on design and technique, manufacturers are more discreet about alloy characteristics that dictate instrument behavior. Along with design and technique, alloy characteristics of endodontic instruments is one of the main variables affecting clinical performance. Modification in NiTi alloys is numerous and may yield improvements, but also drawbacks. Martensitic instruments seem to display better cyclic fatigue properties at the expense of surface hardness, prompting the need for surface treatments. On the contrary, such surface treatments may improve cutting efficiency but are detrimental to the gain in cyclic fatigue resistance. Although the design of the instrument is vital, it should in no way cloud the importance of the properties of the alloy and how they influence the clinical behavior of NiTi instruments. Clinical significance Dentists are mostly clinicians rather than engineers. With the advances in instrumentation design and alloys, they have an obligation to deal more intimately with engineering consideration to not only take advantage of their possibilities but also acknowledge their limitations. How to cite this article Ounsi HF, Nassif W, Grandini S, Salameh Z, Neelakantan P, Anil S. Evolution of Nickel–titanium Alloys in Endodontics. J Contemp Dent Pract 2017;18(11):1090-1096.

A controlled, clinical, double-blind, cross-over study was conducted to assess the efficacy of sugar-free tablets containing green tea extract on oral volatile sulfur-containing compounds (VSC) versus placebo tablets for 30 minutes.To join the study, subjects had to have at least 24 teeth, no report of oral and systemic diseases, and no removable dentures. All eligible participants had to avoid professional oral hygiene and drugs for two weeks, to not be menstruating, to avoid brushing their teeth and tongue, to not smoke, to not consume alcohol, coffee or tea, nor onion, garlic, or licorice for six hours before the test. Moreover, they had to score a level of VSC ≥ 75 ppb at the basal measurement. Subjects were entered into their respective groups after a minimum 48-hour wash-out period. The test tablet (0.7 g) contained 0.05% green tea extract (equivalent of 1 mg polyphenols for three tablets); the control tablet was identical but without the active agent. The OralChroma2™ device was utilized to evaluate VSC in the oral air. The levels were recorded at baseline, after sucking three tablets in succession, and after 30 minutes. Data were analyzed with SPSS software and significance was set at α = 0.05.54 subjects completed the trial (23 men, 31 women). None reported problems linked to green tea. The mean reductions in VSC level from baseline at the end of tablet sucking were 34% (p0.001) in the control and 55% (p0.001) in the test group; after 30 minutes, reductions were 7% in the control (p = NS) and 26% (p0.005) in the test group. The comparisons between the two groups after baseline adjustment showed a statistically significant difference in reductions both at the end of the sucking period (p0.01) and after 30 minutes (p0.01).Tablets containing green tea extract can statistically significantly reduce the oral VSC levels immediately, and after 30 minutes. Moreover, the test tablets reduced oral VSC significantly more than the control tablets.

The purpose of this study was to evaluate the reinforcing effect of fibre-reinforced composites (FRC) applied in premolar teeth with different techniques and minimally invasive post space preparation. Fifty extracted and endodontically treated premolar teeth were used. The teeth were divided into five groups (n = 10) depending on the restorative technique (Groups 1-5). Group 1: one single conventional post, Group 2: one main conventional and one collateral post, Group 3: one elastic post, Group 4: one main elastic and one collateral post, and Group 5: individual post formed of elastic posts. After cementation and core build-up, the specimens were submitted to static fracture resistance test. Fracture thresholds and fracture patterns were measured and evaluated. Group 4 showed the highest average fracture resistance among the tested groups. The multi-post techniques (group 2 and 4) exhibited statistically higher fracture resistance compared to group 1. Regarding fracture patterns, there was no statistically significant difference between the tested groups. Within the limitations of this study, the application of multiple elastic or conventional FRC posts or a single elastic post in the same root canal is beneficial in terms of fracture resistance compared to a single conventional FRC post. The elasticity or the number of posts did not influence the fracture patterns.

RiassuntoObiettiviScopo di questo studio è stato valutare la resistenza alla fatica ciclica di strumenti endodontici utilizzati con un movimento di rotazione continua e alternata.Materiali e metodiSono stati impiegati 40 FlexMaster e 20 MTwo. Tali strumenti sono stati sottoposti a test di fatica.RisultatiSono state rilevate differenze statisticamente significative tra tutti i vari gruppi.ConclusioniConicità minori determinano una maggiore resistenza dello strumento alla fatica ciclica. La rotazione alternata porta a un incremento della vita media dello strumento e conferisce a strumenti di pari conicità maggiore resistenza alla fatica ciclica.SummaryObjectivesThe aim of the present study was to evaluate the fatigue resistance of FlexMaster and MTwo used in continuous rotation and in alternate movement, and the influence of various parameters on this.Materials and methodsForty FlexMaster and 20 MTwo were used, and subjected to fatigue test.ResultsStatistically significant differences were found among all groups.ConclusionsLower taper leads to increased resistance to cyclic fatigue of the instrument. Alternate rotation increases the average life of the instrument, and gives greater resistance to cyclic fatigue to those with similar taper.

Mollo A, Botti G, Prinicipi Goldoni N, Randellini E, Paragliola R, Chazine M, Ounsi HF, Grandini S. Efficacy of two Ni-Ti systems and hand files for removing gutta-percha from root canals. International Endodontic Journal, 45, 1–6, 2012. Abstract Aim To compare the effectiveness of two Ni-Ti systems and hand files for removing gutta-percha and sealer from root canals. Methodology The root canals of 60 single-rooted human teeth were prepared, filled with gutta-percha and sealer (Pulp Canal Sealer; SybronEndo, Orange, CA, USA). Specimens were then divided into three groups (n = 20), and root filling material was removed using MTwo Retreatment Files (group 1); R-Endo (group 2); K-files and Gates-Glidden drills (group 3). After retreatment, the efficacy of each technique was assessed using radiographs that were later digitized and the images analysed using AutoCAD 2004. The percentage of residual gutta-percha was calculated for the whole canal as well as for the coronal, middle and apical thirds. Time required, apically extruded debris and the number of fractured instruments were also recorded. Data were statistically analysed using Kruskal–Wallis and Mann–Whitney U-tests. Results All instrumentation techniques left gutta-percha and sealer remnants inside the root canals. Ni-Ti systems were significantly faster (P

– Objectives: When coronal fracture occurs in anterior teeth, fragment reattachment can be a valid alternative to a direct restoration. The aim of this study was to evaluate the influence of the material and the technique used to reattach the fragment. Materials and methods: Eighty sound maxillary and mandibular incisors were selected and randomly divided into eight groups (n = 10). The incisal third of each tooth was removed using a saw machine. The fragments in groups 1–4 were reattached using resin-based materials: group 1 adhesive, group 2 flow, group 3 composite, group 4 cement; in groups 5–8, the same materials mentioned before were used but a bevel was also performed on both labial and lingual surfaces. Shear bond strength (SBS) was calculated by applying a load incisal to the reattachment line. A two-way Anova was used to evaluate the influence of materials and techniques on the SBS. Results: The technique used was statistically significant (P

Introduction Four generations of methacrylate resin–based sealers have been available commercially. Three of these were introduced during the last 5 years when the concept of simultaneous bonding of root canal sealers to root filling materials and dentin was popularized. Methods This article presents an overview of methacrylate resin–based sealers, with the objectives of clarifying the behavior of these materials and delineating their limitations in clinical application. Results The first generation sealer was introduced in the mid-1970s. The initial enthusiasm associated with its use eventually diminished as a result of its suboptimal physical, biologic, and clinical properties. With advances in self-etching adhesive technology acquired from adhesive dentistry, methacrylate resin–based sealers were reintroduced in the beginning of the 21st century to support the introduction of bondable root canal filling materials. Three different generations of these sealers have since been available commercially. Although some in vitro studies on the sealing ability, self-etching potential, biocompatibility, and removability of the sealers showed better potential over conventional nonbonding sealers, accomplishing the ideal goal of a monoblock in the root canal space with these materials is still regarded as a major challenge. Conclusions On the basis of the in vitro and in vivo data available to date, there appears to be no clear benefit with the use of methacrylate resin–based sealers in conjunction with adhesive root filling materials at this point in their development.

Clinical evidence is lacking regarding the influence of the amount of residual coronal dentin and of post placement on the failure risk of endodontically compromised teeth. The aim of this prospective clinical trial was to assess whether these factors significantly affect the two-year survival of restored pulpless premolars. A sample of 210 individuals provided six experimental groups of 40 premolars in need of endodontic treatment. Groups were defined based on the amount of dentin left at the coronal level. Within each group, in half of the teeth selected at random, a fiber post was inserted inside the root canal, whereas in the remaining half of the premolars, no post was placed. All teeth were covered with a crown. The Cox regression analysis revealed that post placement resulted in a significant reduction of failure risk (p < 0.001). Failure risk was increased for teeth under the “no ferrule” (p = 0.001) and “ferrule effect” conditions (p = 0.004).

Veltri M, Mollo A, Mantovani L, Pini P, Balleri P, Grandini S. A comparative study of Endoflare-Hero Shaper and Mtwo NiTi instruments in the preparation of curved root canals. International Endodontic Journal, 38, 610-616, 2005. Aim To analyse the shaping ability of two new NiTi rotary systems in molar curved canals. Methodology Thirty molar root canals with curva- tures from 24� to 69� were divided into two groups that were balanced in terms of curvature. The canals in one group were shaped using the Mtwo (Sweden & Martina, Padova, Italy) and the canals in the other group using the Endoflare-Hero Shaper (Micro-Mega, Besancon, France) in a modified sequence. Pre- and post-instru- mentation X-rays were taken using a radiographic platform, with a contrast medium being used to enhance canal opacity. The dentine removed at five positions along the canals, the symmetry of canal shaping and the presence of aberrations were analysed through computer-aided measurements. The instru- ment failures, the working time and the changes in working length were also recorded. The Mann-Whit- ney U-test was used for statistical analyses. Results Both systems produced uniform dentine removal and symmetrical canal shapes; there was no significant difference between the systems (P > 0.05). In the apical region, preparations were centred in the canal. A mean loss of working length of 0.55 mm for Mtwo and 0.58 mm for Endoflare-Hero Shaper was detected, with no significant differences between the instruments (P > 0.05). No aberrations were seen and no instruments separated. The mean working time was 124.4 s for the Mtwo system and 141.3 s for the Endoflare-Hero Shaper but this difference was not statistically significant (P > 0.05). Conclusion The systems tested in this study were effective in shaping curved canals in extracted teeth.

Adhesive dentistry should effectively restore the peripheral seal of dentin after enamel removal. We hypothesize that non-rinsing, simplified, one-step self-etch adhesives are effective for minimizing dentin permeability after tooth preparation procedures. Crown preparations in vital human teeth were sealed with Adper Prompt, Xeno III, iBond, or One-Up Bond F. Epoxy resin replicas were produced from polyvinyl siloxane impressions for SEM examination. Dentin surfaces from extracted human teeth were bonded with these adhesives and connected to a fluid-transport model for permeability measurements and TEM examination. Dentinal fluid droplets were observed from adhesive surfaces in resin replicas of in vivo specimens. In vitro fluid conductance of dentin bonded with one-step self-etch adhesives was either similar to or greater than that of smear-layer-covered dentin. TEM revealed water trees within the adhesives that facilitate water movement across the polymerized, highly permeable adhesives. Both in vitro and in vivo results did not support the proposed hypothesis.

Objective. The objective of this clinical report was to evaluate the effectiveness of a microbrush as a carrier of priming-adhesive solution in formation of resin tags, adhesive lateral branches, and resin-dentin interdiffusion zone (RDIZ) when the brush was used to bond fiber posts under clinical conditions. Study Design. Twenty endodontically treated teeth, already scheduled for extraction for endodontic or periodontal reasons, were selected for this study. The patients were informed, and their written consent was obtained. The samples were randomly divided into 2 groups of 10 samples each. In group 1, One-Step (Bisco, Schaumburg, Ill) was applied with a brush with Duo-Link resin cement (Bisco). In group 2, One-Step was applied with a microbrush with Duo-Link resin cement (Bisco). Use of the adhesive systems and resin cements was strictly according to manufacturers' instructions. The priming-adhesive solution was light-cured before the dual resin cement and the post were placed. Twenty Aestheti-Plus posts (white quartz fiber posts; RTD, St. Egreve, France) were used. A week after application, the root samples were extracted and processed for SEM observations. Results. Both adhesive systems showed RDIZ and resin tag and adhesive lateral branch formation. In Group 2 samples, RDIZ morphology was easily detectable and uniform along root canals. Also, resin tag formation was well represented in all thirds. In group 1 samples, resin tag formation at the apical third and RDIZ formation was less evident. Statistically significant differences were found among the two groups at the apical third. Conclusion. The microbrush permitted a more uniform RDIZ and resin tag formation along the entire length of the canal than did the standard brush. The microbrush can be routinely used for bonding fiber posts into root canal preparations. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2002;94:627-31)

The purpose of this study using a scanning electron microscope was to investigate the efficacy of four different irrigation techniques after canal preparation with Profile Ni-Ti rotary instruments. A modified technique for the use of Glyde File Prep is proposed. Forty anterior teeth were divided into four groups, instrumented, and irrigated as follows: physiological solution (group A), 2.5% sodium hypochlorite (group B), 2.5% sodium hypochlorite and Glyde File Prep (group C), and 2.5% sodium hypochlorite and Glyde File Prep applied at the end of the preparation with sterile paper points (group D). After scanning electron microscopic evaluation at three different levels, debris, smear layer, and dentinal tubules were scored. Groups A and B had significantly more smear layer and less open tubules on the canal walls compared with the group C and group D samples. Differences in the mean amount of debris between group A samples and other irrigation regimes were statistically significant.

Objectives: The objective of this investigation was to evaluate the effectiveness of three ‘one-bottle’ and two ‘three step’ adhesive systems (as controls) in the formation of resin tags, adhesive lateral branches and a resin dentin interdiffusion zone (RDIZ) when used to bond fiber posts under clinical conditions. This study was performed using standardized SEM observations and scoring resin tag formation and density. Methods: Fifty root canal treated teeth, already scheduled for extraction for endodontic or periodontal reasons, were selected for this study. The patients were informed and their written consent was obtained. The samples were randomly allocated to five groups of ten samples each. Group 1: All Bond 2 with C & B (Bisco); Group 2: Scotchbond Multipurpose Plus with Opal Luting Composite (3M); Group 3: Scotchbond 1 in combination with Rely X ARC resin cement (3M); Group 4: One-step with C & B resin cement (Bisco); Group 5: All Bond Experimental with Post Cement HI–X (Bisco). The adhesive systems and resin cements were used strictly according to the manufacturers’ instructions. The priming-adhesive solution of each ‘one-bottle’ system was light-cured before placing the resin cement and the post. Fifty Aestheti-Plus posts (white quartz fiber posts, RTD, France) were used. A week later, the roots were extracted and processed for SEM observations. Results: All the adhesive systems showed a RDIZ and resin tag and adhesive lateral branch formation. Microscopic examination of the restored interfaces of Groups 1 and 2 showed a higher percent of RDIZ than those found in samples of Groups 3, 4 and 5. RDIZ morphology was easily detectable and uniform in the first two thirds of the root canals, whilst in the apical third the RDIZ was not uniformly present. Resin tag morphology and formation were significantly more detectable in the cervical and middle areas than in the apical zone. No statistically significant differences were found among the five groups coronally, while in the apical and middle thirds two ‘one-bottle’ systems (Groups 3 and 4) showed significantly less resin tags than the control Groups 1, 2 and the experimental Group 5. No statistically significant differences were found among the three ‘one-bottle’ systems in the three evaluated areas. The standardization of SEM observations and scoring resin tag formation allowed statistical evaluation. Conclusions: The ‘three step’ adhesive systems can create a wider micromechanical interlocking between adhesive materials and etched dentin than ‘one-step’ systems.

Objective: Different single-file instruments and kinematics have been introduced on the market. It is important to know the cyclic fatigue performance of these instruments in these new kinematics such as reciprocation of Optimum Torque Reverse (OTR) motion. The aim of this study was to evaluate the resistance to cyclic fatigue of F6 SkyTaper and OneShape used in continuous rotation (proper rotation) or in reciprocating OTR motion. Methods: A total of forty-eight nickel-titanium files were tested. Twenty-four instruments of both brands were divided into two groups (n=12) on the basis of the motion tested: continuous rotation (group 1) or reciprocating OTR motion (group 2). Resistance to cyclic fatigue was determined by recording time to fracture (TtF) in a stainless steel artificial canal with a 60° angle of curvature and 5 mm radius of curvature. Data were analysed by two-way analysis of variance and post-hoc Bonferroni tests for multiple comparisons with P

A controlled, clinical, double blind study was conducted to assess the efficacy of a sugar-free chewing gum containing calcium hydroxyapatite on dentin hypersensitivity, versus a placebo chewing gum with no active ingredients, after one and two weeks.One hundred and seven subjects joined the trial and were allocated into the test or the control (placebo) group by a random table. The test chewing gum contained calcium hydroxyapatite and dicalcium phosphate dihydrate; the control chewing gum was identical, but without those ingredients. Participants were required to chew two pieces of their assigned chewing gum three times a day. Dentin hypersensitivity was evaluated following three clinical test indexes (tactile, air blast, cold water) and one subjective index.One hundred subjects completed the study with 50 allocated to each group. The clinical test index reductions after one and two weeks in the test group were, respectively, 36% and 54% for tactile, 35% and 66% for air blast, and 24% and 49% for cold water. The clinical test index reductions after one and two weeks in the control group were, respectively, 16% and 30% for tactile, 11% and 25% for air blast, and 14% and 31% for cold water. These reductions at one and two weeks were significant for the test group (p0.01). For the control group they were significant (p0.01) only at two weeks. The comparisons between the groups at two weeks showed a significant statistical difference between the test and the control gum for tactile (p0.01), for air blast (p0.001), for cold water (p0.05), and for the subjective index (p0.05).In this trial, the group using the chewing gum containing calcium hydroxyapatite had a statistically significant reduction in all clinical test indexes for dentin hypersensitivity after one and two weeks, and a statistically significant reduction compared to the control gum group.

Objective: The aim of this study was to evaluate the shear bond strength to dentin of primary molars of a new self-adhering flowable resin composite with two ionomer-based cements and one flowable resin composite in combination with two different adhesive systems. Study design: Fifty primary molars were grinded on the occlusal surface to obtain flat dentin substrate and randomly divided into 5 groups (n=10): OFL:Phosphoric Acid/Optibond FL/Premise Flow; OAO:Optibond All-In-One/Premise Flowable; II:Polyacrylic Acid/Fuji II; IX:Polyacrylic Acid/Fuji IX; V:Vertise Flow. Cylinders (3mm diameter – 5mm height) of restorative material were built-up in three increments over the dentin surfaces. A shear load was applied until failure. Bond strength values were statistically analysed with Kruskall-Wallis ANOVA followed by Dunn's test (P

This study was designed to determine if the alloy composition shares an influence with the geometric design on the physical behavior of nickel-titanium rotary endodontic instruments. ProTaper, HERO, and K3 files were selected. After sterilized and cleaning with alcohol, surface analysis was performed using energy dispersive spectroscopy. Measurements were performed on the active part and on the shank. SEM images of fractured instruments were also obtained and assessed. All three types of instruments were composed mainly of Nickel (54.3%, SD +/- 0.8) and Titanium (45.2%, SD +/- 0.9). SEM images revealed similar aspect with the presence of Kirkendall voids regularly distributed in the alloy. The results indicate that the difference in properties and behavior of these three endodontic rotary shaping instruments is solely related to the respective geometric characteristics of the instrument design.

A controlled, clinical, double-blind study was conducted to assess the efficacy of a sugar-free chewing gum containing zinc acetate and magnolia bark extract (MBE) on oral volatile sulfur-containing compounds (VSC) versus a placebo sugar-free chewing gum for two hours.To participate in the study, subjects had to have at least 24 of their teeth, no report of oral and systemic diseases, and no removable dentures. All 168 eligible participants had to avoid any professional oral hygiene, refrain from taking medicine for two weeks, and not be menstruating. They were also instructed not to brush their teeth and tongue, smoke, drink alcohol, or eat onion, garlic, or licorice for the six-hour period before the visit and during the test. Moreover, to join the protocol, they had to show a VSC score ofor = 75 ppb at the baseline measurement. One-hundred and twenty-three subjects (67 men and 56 women, mean age 37) met the criteria at baseline and were entered into either the test or control group by assignment from a table of randomized numbers. The test chewing gum (2.23 g) contained zinc acetate 0.012% and magnolia bark extract 0.15% in weight; the control gum was equivalent without these active agents. The OralChroma device was utilized to evaluate total oral VSC. Their levels were recorded at baseline, after ten minutes of mastication, after one hour, and after two hours. Data were analyzed with SPSS software and the level of significance was set at alpha = 0.05.One-hundred and twenty-three subjects completed the trial (62 in the control group and 61 in the test group); none reported problems linked to zinc acetate or magnolia bark extract. The mean percentage reductions from baseline at the end of the 10-minute chewing were 31.2% in the control group (p0.05) and 50.9% in the test group (p0.05). One hour later the reductions were 6.9% in the control group and 27.6% in the test group (p0.05); two hours later the reductions were 2.3% in the control group and 13.6% in the test group. The comparison of the two groups after baseline adjustment showed a statistically significant difference (p0.05) in VSC reductions between the test and control chewing gums at the end of the mastication period and after one hour.Chewing gum containing zinc acetate and magnoliabark extract can significantly reduce the oral VSC levels for more than one hour. Moreover, the test chewing gum reduces oral VSC significantly more than a control chewing gum.

When coronal fracture occurs in anterior teeth, fragment reattachment can be a valid alternative to a direct restoration. The aim of this study was to evaluate the influence of the material and the technique used to reattach the fragment.Eighty sound maxillary and mandibular incisors were selected and randomly divided into eight groups (n = 10). The incisal third of each tooth was removed using a saw machine. The fragments in groups 1-4 were reattached using resin-based materials: group 1 adhesive, group 2 flow, group 3 composite, group 4 cement; in groups 5-8, the same materials mentioned before were used but a bevel was also performed on both labial and lingual surfaces. Shear bond strength (SBS) was calculated by applying a load incisal to the reattachment line. A two-way Anova was used to evaluate the influence of materials and techniques on the SBS.The technique used was statistically significant (P0.001), while the material was not (P = 0.793).The choice of material seems to have no influence on the SBS, whereas a bevel performed on the labial and lingual surfaces can significantly improve the SBS of the reattached fragment.

The study aimed at assessing and estimating the fatigue resistance of different fiber posts and to observe their ultrastructures through SEM. Six types of fiber posts were used: GC Fiber Post (Group 1), ParaPost Fiber White (Group 2), FibreKor (Group 3), DT Light-Post radiopaque (Group 4), FRC Postec (Group 5), and Luscent Anchors (Group 6). Ten out of 15 posts within each group were used for the fatigue test, and the other five were processed for SEM evaluation. The fatigue test revealed that Groups 1, 4, and 5 performed better than all the other groups, and that their performance differed significantly from the other tested groups from a statistical standpoint. For SEM analysis, Groups 1, 4, and 5 also obtained better results. Through correlation analysis, an absence of correlation between fatigue resistance and structural characteristics suggested that the latter reflected more of the divergence inherent in the manufacturing process of fiber posts.

Objectives This review aimed at summarizing the laboratory evidence collected on the retentive ability of adhesive posts since their introduction in dentistry. Data Data were searched in articles published or in press in peer-review journals listed in MEDLINE. Sources Papers were retrieved through PubMed. Study selection To collect the evidence of interest, the following search terms were used: bond* AND fiber post AND in vitro; lut* AND fiber post AND in vitro; push-out AND fiber post; pull-out AND fiber post; microtensile AND fiber post. “Related Links” were also considered and articles cited in the initially retrieved papers were included if relevant. No time limit was given to the query. Conclusions Seventy relevant papers were reviewed. The retentive ability of adhesive posts has been tested with the microtensile technique, post-pull-out and push-out tests. If small-sized specimens are obtained, such as in microtensile and thin-slice push-out, stress uniformity is favoured, local differences in bonding conditions can be discerned, and the number of teeth needed for the test can be reduced. Although adhesion to intraradicular dentin is more challenging to achieve than bonding to crown tissues, the post-retention achieved with current luting systems and techniques is adequate to ensure the clinical success of adhesive post-retained restorations. To enhance the bond at the post-core and post-cement interfaces, several chemical pre-treatments of the post-surface have been tested with positive results. Self-adhesive resin cements, recently proposed to simplify the post-luting procedure, should be investigated further with regard to durability.