Browsing by Author "Belli, S."

Now showing 1 - 14 of 14

Adhesion of Two New Glass Fiber Post Systems Cemented With Self-Adhesive Resin Cements
(MDPI Multidisciplinary Digital Publishing Institute, 2019) Özlek, E.; Neelakantan, P.; Matinlinna, J.P.; Belli, S.; Ugur, M.; Kavut, I.
The aim of this in vitro study was to evaluate the adhesion strength of two new fiber post systems (FiberSite™ Post and Cytec™ Blanco Post) cemented with two different adhesive resin cements (Panavia™ SA and Maxcem™ Elite). Root canals of sixty extracted human mandibular premolars were prepared using ProTaper Universal™ rotary files (Dentsply Sirona Endodontics, York, PA, USA). The root canals were irrigated with 5.25% sodium hypochlorite (NaOCl) during instrumentation. After root canal preparation, the canals were irrigated with 2 mL of 17% EDTA (1 min), followed by 2 mL of 5.25% (5 min) NaOCI, and 2 mL saline. The root canals were dried with paper points and divided randomly into two study groups (n = 30) according to the type of post system: Group 1, FiberSite™ Post (MegaDental, Partanna, Italy); and group 2, Cytec™ Blanco Post (Hahnenkratt, Königsbach-Stein, Germany), with one of the two adhesive resin cements: Subgroup A, Panavia™ SA Cement Plus Automix (Kuraray, Osaka, Japan); subgroup B, Maxcem™ Elite (Kerr, Orange, CA, USA). Following thermocycling, the adhesion strength was evaluated using the push-out adhesion (bond) strength test. Fractographic analysis was performed using stereomicroscope. The data were analyzed using two-way analysis of variance (p = 0.05). The adhesion strength values of both the posts were significantly higher when cemented with subgroup B (Maxcem™ Elite). The highest adhesion strength value was demonstrated by group 1B (FiberSite™ post cemented with Maxcem™ Elite cement). The type of post did not have a significant impact on the bond strength values for either cement material. © 2019 by the authors.
Direct Restoration of Endodontically Treated Teeth: a Brief Summary of Materials and Techniques
(Springer Science and Business Media B.V., 2015) Belli, S.; Eraslan, O.; Eskitascioglu, G.
The restoration of endodontically treated teeth remains a challenge. The success of the final restoration depends mostly on the structure of the remaining tooth. Although the materials and procedures available today result in successful restoration of root-filled teeth via direct (in situ) techniques, one should first consider the amount of the coronal tooth structure remaining as well as the functional requirements. Restoration using direct composite resin is a good treatment option, but polymerization shrinkage is one of the major limitations of this material. The application of various base materials under the composite resin is an effective method. Covering the cusps with the restorative material is another option to save the remaining tooth structure; however, some materials may be unsuitable in stress-bearing areas. Materials applied to the orifice of a root canal also have a major effect on tooth biomechanics. This article reviews the direct restoration of endodontically treated teeth and discusses the current materials and techniques used for this purpose. © 2015, Springer International Publishing AG.
The Effect of Cavity Shape and Hybrid Layer on the Stress Distribution of Cervical Composite Restorations
(Dental Investigations Society, 2011) Eliguzeloglu, E.; Eraslan, O.; Omurlu, H.; Eskitascioglu, G.; Belli, S.
Objectives: The aim of this finite elemental stress analysis study was to evaluate the effect of cavity shape and hybrid layer on the stress distribution of the mandibular premolar tooth under occlusal loading. Methods: The mandibular premolar tooth was selected as the model based on the anatomical measurements suggested by Wheeler. Four different mathematical models were evaluated: 1) a saucer-shaped non-carious cervical lesion restored with a composite without a hybrid layer, 2) a saucer-shaped non-carious cervical lesion restored with a composite with a hybrid layer, 3) a wedge-shaped non-carious cervical lesion restored with a composite without a hybrid layer, and 4) a wedge-shaped non-carious cervical lesion restored with a composite with a hybrid layer. A 200 N force was applied from the buccal tubercule and central fossa of the premolar tooth. The findings were drawn by the SAPLOT program. Results: In models 2 and 4, the output showed that a hybrid layer acts as a stress absorber. Additionally, when the cavity shape was changed, the stress distribution was very different. Conclusions: Cavity shape and hybrid layer play an important role in stress distribution in cervical restorations.
The Effect of Different Materials and Techniques on Stress Distribution in Cad/Cam Endocrowns
(Springer, 2020) Eskitascioglu, M.; Kucuk, O.; Eskitascioglu, G.; Eraslan, O.; Belli, S.
Computer-aided design/manufacturing (CAD/CAM) endocrowns are commonly applied to strengthen endodontically treated teeth with too much tissue loss. Monolithic or multilayer structures may be used for this purpose. Restorations made with multilayering technique may mimic natural teeth better. The purpose of this finite elemental analysis (FEA) research was to appraise the impact of different materials and application methods on the stress effect in CAD/CAM applied endocrowns. A 3-dimensional mathematical model simulating an endodontically treated mandibular first molar was modeled. The sample was then modified to imitate the ceramic endocrown applied molar tooth. Three FEA models were then created from this main model to simulate the following endocrown structures: 1: lithium disilicate reinforced glass ceramic, 2: monolithic zirconia, 3: multi-layered glass ceramic and glass-fiber endocrown (the core structure was composed of glass-fiber while the crown is prepared by glass ceramic). The SolidWorks/CosmosWorks programs were used as structural analysis programs. The materials used in the study were accepted as homogeneous and isotropic. A 300 N load was applied to the occlusal surfaces of the restored teeth. The results of the study are presented according to the von Mises criteria. The von Mises stresses recorded at the cavity base were 0.417-0.7, 0.6-0.85, and 0.083-0.25 MPa, respectively. The multilayering technique reduced stresses as compared to the other two different designs and materials and showed similar stress distributions with the natural tooth model. Models simulating teeth with a zirconia endocrown showed the highest stresses. The multilayering technique using fiber-reinforced glass ceramic as a core and glass ceramic as a crown reduced the stresses and showed stress distributions similar to natural teeth. This technique can be used to create biomimetic restorations with a core material, which mimics dentin (glass-fiber reinforced ceramic) and crown material, which mimics enamel (glass ceramic).
The Effect of Different Posts on Fracture Strength of Roots With Vertical Fracture and Re-Attached Fragments
(Wiley-blackwell, 2010) Ozcopur, B.; Akman, S.; Eskitascioglu, G.; Belli, S.
P>The aim of this in vitro study was to test the effect of different post systems on fracture strength of roots with re-attached fragments. Root canals of eighty extracted single-rooted human teeth were instrumented (ProFile) and randomly divided into two groups. The roots in the first group were vertically cracked, and the fragments were re-attached using Super Bond C&B (Sun Medical, Tokya, Japan). The roots in the second group were kept sound. Obturation of the roots was performed with MetaSEAL (Sun Medical) and gutta-percha. Post spaces were prepared, and the roots were restored with one of the followings: UniCore (Ultradent), Everstick (Stick Tech), Ribbond (Ribbond), ParaPost (Coltene/Whaledent) (n = 10). Four mm high build-ups were created (Clearfil DC Bond Core; Kuraray, Tokyo, Japan). Compressive loading of the samples was performed after 24 h (1 mm min-1). Mean load necessary to fracture each sample was recorded (Newton) and statistically analysed (One-way anova, t-tests). ParaPost showed the highest fracture strength among the roots with re-attached fragments (P < 0.05). UniCore and ParaPost systems showed similar fracture strength in the sound roots (P > 0.05). Re-attached fragments significantly reduced the fracture strength of roots in UniCore group (P = 0.000). Ribbond post showed mostly repairable fractures. Metal post (ParaPost) showed the highest fracture strength in the roots with re-attached fragments; however, fracture pattern was 41% non-repairable. Re-attached fragments significantly reduced the fracture strength of the roots in UniCore group. Prefabricated posts showed similar fracture strength in the sound roots. Customized post systems EverStick and Ribbond showed mostly repairable failure after loading in sound roots or roots with re-attached fragments.
Effects of Naocl, Edta and Mtad When Applied To Dentine on Stress Distribution in Post-Restored Roots With Flared Canals
(Wiley, 2014) Belli, S.; Eraslan, O.; Eraslan, O.; Eskitascioglu, M.; Eskitascioglu, G.
AimTo evaluate the effect of NaOCl, EDTA and MTAD on the stress distribution and levels in roots with flared canals and three different aesthetic post systems using finite element stress analysis (FEA). MethodologyThree-dimensional (3D) FEA models simulating a maxillary incisor with excessive structural loss and flared root canals were created. The dentine of the first models of each post group was assumed as homogenous, whereas the others were deemed as having their elastic modulus affected up to 100m deep as a result of irrigation protocol (5.25 NaOCl, 17% EDTA and MTAD for 2h). A sound incisor tooth model was used as the control. Restorations were created according to the post system used (pre-fabricated fibre post (PFP)), polyethylene fibre (Ribbond) post and core build-up (RBP), and one-piece milled zirconia post and core (ZP). Ceramic crowns were added to the models. A 300-N static load was applied at the centre of the palatal surface of the models to calculate the stress distributions. The SolidWorks/Cosmosworks structural analysis programmes were used for FEA analysis. Results were presented by considering von Mises criteria. ResultsThe analysis of the von Mises stresses revealed that RBP created less stress in the remaining root dentine when compared to PFP and ZP. ZP maintained the stresses inside its body and reduced stress on the palatal surface of the root; however, it forwarded more stress towards the apical area. NaOCl-, EDTA- and MTAD-treated dentine increased the stresses within the root structure regardless of the effect of the post system used (11-15.4 MPa for PFP, 9.5-13.02 MPa for RBP and 14.2 MPa for ZP). Amongst the irrigation solutions used, EDTA and MTAD increased the stresses more than NaOCl in all models. All the irrigation solutions showed the same stress levels and distributions in the ZP model. ConclusionNaOCl-, EDTA- and MTAD- treated dentine and a rigid post with high elastic modulus may increase fracture risk in roots with flared canals by increasing the stresses within root dentine. Therefore, solutions that alter the elastic modulus of dentine less (such as NaOCl) or an individually shaped post-core system constructed with a material that has an elastic modulus close to dentine (polyethylene fibre) should be used in weak roots.
Influence of Several Fibre-Reinforced Composite Restoration Techniques on Cusp Movement and Fracture Strength of Molar Teeth
(Wiley, 2011) Akman, S.; Akman, M.; Eskitascioglu, G.; Belli, S.
P>Aim To compare mean cusp movement in molar teeth with endodontic access and mesial-occlusal-distal (MOD) cavities before and after restoration with several fibre-reinforced composite restoration techniques under loading and to evaluate the effect of restoration technique on fracture strength. Methodology Reference points were marked at the mesial cusp ridges of extracted human mandibular molar teeth. Digital images were taken under loading (300 N) using a stereomicroscope (Leica MZ16A; Wetzlar, Germany). Three-dimensional (3D) distances between the reference points were recorded (Leica, Stereo-Explorer, 2.1) as controls. Standard MOD cavities were prepared and restored as follows (n = 10), group 1: composite restoration (Clearfil AP-X; Kuraray, Tokyo, Japan); group 2: cavity lined with polyethylene fibre (Ribbond, Ribbond Inc., Seattle, WA, USA) in combination with flowable resin (Protect-Liner F; Kuraray, Tokyo, Japan) before composite restoration; group 3: polyethylene fibre inserted on occlusal surface of the tooth from buccal to lingual after finishing the composite restoration; group 4: missing walls were restored with composite resin and inner surfaces of the axial walls were then reinforced with polyethylene fibre placed circumferentially before the composite restoration. The restored teeth were re-loaded, digital images were re-taken and the 3D distance between the reference points was recorded in mu m. Comparisons of the restoration techniques, the effectiveness of restoration for each group were analysed statistically (Kruskall-Wallis, paired-samples t-test). The teeth were then loaded until failure (5 mm min-1), the data were recorded (N) and analysed statistically (Kruskall-Wallis test). Results A significant difference occurred amongst the groups in terms of cusp movement (P = 0.018). All the groups revealed a decrease in inter-cuspal width when compared to their initial records. The mean values of these decreases were as follows: group 1 17.6 (P = 0.003), group 2 6.7 (not sig), group 3 6.6 (not sig) and group 4 0.85 (not sig) mu m. No significant difference was found amongst the fracture strength values (P = 0.22). In group 1, 90% of the fractures were non-restorable, whereas in group 3 100% of the fractures were restorable. Conclusions Regardless of restoration technique, fibre reinforcement of composite restorations decreased cusp movement in molar teeth with MOD and endodontic access cavities but did not affect fracture strength.
Monoblocks in Root Canals: a Finite Elemental Stress Analysis Study
(Wiley-blackwell, 2011) Belli, S.; Eraslan, O.; Eskitascioglu, G.; Karbhari, V.
Belli S, Eraslan O, Eskitascioglu G, Karbhari V. Monoblocks in root canals: a finite elemental stress analysis study. International Endodontic Journal, 44, 817-826, 2011. Aim To investigate using finite element stress analysis (FEA) primary, secondary and tertiary monoblocks created either by adhesive resin sealers or by different adhesive posts and to evaluate the effect of interfaces on stress distribution in incisor models. Methodology Seven maxillary incisor FEA models representing different monoblocks using several materials were created as follows: (a) primary monoblock with Mineral Trioxide Aggregate; (b) secondary monoblock with sealer (MetaSEAL) and Resilon; (c) tertiary monoblock with EndoREZ; (d) primary monoblock with polyethylene fibre post-core (Ribbond); (e) secondary monoblock with glass-fibre post and resin cement; (f) tertiary monoblock with bondable glass-fibre post; (g) tertiary monoblock with silane-coated ceramic post. A 300 N load was applied from the palatal surface of the crown with a 135 degrees angle to the tooth long axis. Materials used in the study were assumed to be homogenous and isotropic except the glass-fibre post; the results are expressed in terms of von Mises criteria. Results Maximum stresses were concentrated on force application areas (18-22.1 MPa). The stresses within the models increased with the number of interfaces both for the monoblocks created by the sealers (1.67-8.33 MPa) and for the monoblocks created by post-core systems (1.67-11.7 MPa). Conclusions Stresses within roots increased with an increase in the number of the adhesive interfaces. Creation of a primary monoblock within the root canal either by an endodontic sealer or with an adhesive post-core system can reduce the stresses that occur inside the tooth structure.
Periodontal Ligament Fibroblast Response To Root Perforations Restored With Different Materials - a Laboratory Study
(Wiley-blackwell, 2012) Hakki, S. S.; Bozkurt, S. B.; Ozcopur, B.; Purali, N.; Belli, S.
Aim To compare the effect of several materials on the attachment of periodontal ligament (PDL) fibroblasts to experimentally perforated root surfaces. Methodology Root specimens (size 5 x 5 mm) were obtained from extracted human molar teeth and perforations with a 1 mm diameter were created. One group was kept as a control and the rest were repaired with the following materials: Amalgam, Dyract, IRM, Super Bond C&B and Mineral trioxide aggregate (MTA). PDL fibroblasts were placed at a density of 8 x 104 cells on the root specimens, incubated on tissue culture inserts (48 h) and then transferred to 48 well-plates. MTT assays were performed at 48 and 96 h for PDL fibroblast survival. Cell attachment was observed using confocal microscopy on days 2 and 5. Total RNAs from the root specimens were isolated on day 5 and type I collagen (COL I) and Runt-related transcription factor 2 (Runx2) mRNA expressions were checked using Quantitative-Polymerase Chain Reaction (QPCR). For the MTT assay and QPCR, one-way analysis of variance (anova) and Tukey HSD multiple comparison tests were used to compare the groups. Results Mineral trioxide aggregate resulted in a significantly higher cell density (P < 0.001). Dyract, IRM and Super Bond C&B groups had a lower cell density when compared with the control and MTA groups at 48 h (P < 0.001). Confocal microscopy revealed that, among the experimental groups, the MTA group had the largest viable cell population over the restoration site when compared with the other materials; however, reduced cell attachment was noted in all groups when compared with the control. Increased Runx2 mRNA expressions were noted in MTA (P < 0.001) and IRM (P < 0.01) groups when compared with control and other tested materials. COL I transcripts were increased in IRM (P < 0.01), D, C&B and MTA (P < 0.001) when compared with the control. Conclusion Mineral trioxide aggregate provided a more favorable environment for PDL cell adhesion and growth.
Prolidase, Paraoxonase-1, Arylesterase Activity in Oral Squamous Cell Carcinoma
(Yuzuncu Yil Universitesi Tip Fakultesi, 2021) Belli, S.; Demir, H.; Ozdemir, B.; Demir, C.
In many types of cancer, reactive oxygen and nitrogen products have been detected at high levels. Arylesterase, and paraoxonase1 are esterase enzymes that have strong antioxidant characteristics. The prolidase enzyme is a rate-limiting metalloenzyme which also plays a role in collagen turnover, and is dependent on its NO-activity. In this study, we aimed to investigate the possible relationship between serum paraoxonase1, arilesterase and prolidase enzyme activity in patients with squamous cell carcinoma of the oral cavity and to investigate the etiology and mechanism of oral cavity cancer. The study included 24 patients with oral cavity cancer, and 22 healthy age-and sex-matched individuals. Arylesterase, paraoxonase1 and prolidase activities were measured using spectrophotometry. Paraoxonase1 activity was 11.6±2.32 nmol/l in the patient group and 29.46±6.18 nmol/l in the controls. Arylesterase activity was 32.2±14.57 nmol/l in the patient group and 80.71±7.23 nmol/l in the controls. Prolidase activity was 39.51±3.02 nmol/l in the patient group and 19.53±1.13 nmol/l in the controls. The mean paraoxonase1 and arylesterase levels in the patient group were statistically lower than the control group and the mean prolidase levels were high (p = 0.0001). In our study, arylesterase and paraoxonase1 enzyme activity was low in patients with oral cav ity cancer. The prolidase activity was higher in the same group. As a result, paraoxonase1, arylesterase and prolidase enzyme activities play an important role in the etiopathogenesis of oral cavity cancers. In addition, more research should be done on bot h clinical and molecular levels of oral cavity cancer. © 2021, Yuzuncu Yil Universitesi Tip Fakultesi. All rights reserved.
Psychopathology and Psychiatric Co-Morbidities in Patients Seeking Rhinoplasty for Cosmetic Reasons
(University of the West Indies, 2013) Belli, H.; Belli, S.; Ural, C.; Akbudak, M.; Oktay, M.F.; Cim, E.F.A.; Pehlivan, B.
Aim: The purpose of the study was to examine psychopathological traits and psychiatric co-morbidities in seekers of cosmetic rhinoplasty. Subjects andMethod: Fifty persons seeking cosmetic rhinoplasty and 50 control subjects were admitted to the study. Beck Depression Inventory (BDI), Beck Anxiety Inventory (BAI) and Symptom Checklist - 90 [Revised] (SCL-90-R) were administered to people who requested cosmetic rhinoplasty and control subjects. All participants were also screened by the Structured Clinical Interview for DSM-IV-(SCIDI/ CV, SCID-II). Results: Thirteen cosmetic rhinoplasty seekers [CRS] (26%) and three control subjects (6%) had at least one psychiatric diagnosis. There was a significant difference between the two groups (p = 0.006). Beck depression inventory (p = 0.002) and BAI (p = 0.046) levels above the cut-off point were significantly higher in the CRS group than in the normal control. Somatoform disorders were statistically higher in the CRS than control group (p = 0.007). Nine CRS (18%) and two control subjects (4%) had at least one personality disorder. There were differences between the two groups (p = 0.025). The average of SCL-90-R was significantly higher in the CRS than in the control subjects (p < 0.001). The most prevalent somatoform disorders of the CRS were six with body dysmorphic disorder [BDD] (12%). The most prevalent personality disorders of the CRS were three with avoidant (6%) and three with narcissistic (6%) personality. Conclusion: Assessment of detailed psychopathological aspects and psychiatric co-morbidities could help to define the clinical profile of people requesting cosmetic rhinoplasty in cosmetic surgery settings. Research into these factors may be important as it is essential to detect crucial problems such as personality disorders and BDD before surgery.
The Response of Cementoblasts To Calcium Phosphate Resin-Based and Calcium Silicate-Based Commercial Sealers
(Wiley, 2013) Hakki, S. S.; Bozkurt, B. S.; Ozcopur, B.; Gandolfi, M. G.; Prati, C.; Belli, S.
Hakki SS, Bozkurt BS, Ozcopur B, Gandolfi MG, Prati C, Belli S. The response of cementoblasts to calcium phosphate resin-based and calcium silicate-based commercial sealers. International Endodontic Journal, 46, 242-252, 2013. Aim To investigate cell viability and gene expression of cementoblasts (OCCM.30) exposed to extractable components released by resin-based sealers with different chemical composition Hybrid Root Seal (HRS), SimpliSeal (SS), Real Seal (RS) and AH Plus (AH) and by a MTA-based sealers Tech Biosealer Endo (TBE). Methodology Discs of all materials were prepared and allowed to set in humid conditions at 37 degrees for 48h. The discs were then incubated for 72h at 37 degrees C to obtain material extracts (1/1) in DMEM. The extracts containing the components released by the sealers were filtered and other dilutions (1/2, 1/4) were prepared from the original solution (1/1). Original and diluted solutions were tested on the cementoblasts. Impedance-based real-time cell analysis (RTCA) was used to evaluate cell viability, quantitative real-time polymerase chain reaction (QRT-PCR) was used to examine the expression of mineralization-related genes (osteocalcin; OCN, Runt-related transcription factor-2; Runx2, collagen type 1; COL I, alkaline phosphatase; ALP). For statistical analysis, one-way analysis of variance (anova) and Tukey's honestly significant difference (HSD) tests were used. Results TBE (1/2), RS (1/2, 1/4), and HRS (1/2, 1/4) significantly decreased cell viability (P<0.001). AH (1/2, 1/4) and SS (1/2, 1/4) had similar cell viability to the control at 30h. All tested materials significantly decreased cell viability when compared to the control group except AH (1/2, 1/4) and SS (1/4) at 90h. All of the tested sealers reduced COL I mRNA expressions when compared to the control. SS was associated with significant increases in OCN and Runx2 mRNA expressions when compared to the control (P<0.001). Whereas all of the dilutions of TBE, RS and HRS significantly decreased BSP mRNA expressions (P<0,001), 1/2 and 1/4 dilutions of SS increased BSP mRNA expression (P<0,001). Except the 1/4 dilutions of AH and SS, all the sealer dilutions significantly reduced ALP mRNA expression in cementoblasts (P<0,001). Conclusions SimpliSeal and AH Plus resulted in more favourable response to cementoblasts because of their regulation potential on the mineralized tissue-associated protein's mRNA expressions.
Retraction: Stress Distribution in Cad/Cam Endocrowns Produced Via Different Materials and Techniques: a Numerical Simulation (Retraction of Vol 52, Pg 812, 2020)
(Springer, 2023) Eskitascioglu, M.; Kucuk, O.; Eskitascioglu, G.; Eraslan, O.; Belli, S.
Stress Distribution in Cad/Cam Endocrowns Produced Via Different Materials and Techniques: a Numerical Simulation
(Springer, 2022) Eskitascioglu, M.; Kucuk, O.; Eskitascioglu, G.; Eraslan, O.; Belli, S.
Computer-aided design/manufacturing (CAD/CAM) endocrowns are commonly applied for the strengthening of endodontically treated teeth with excessive tissue loss. Monolithic or multilayer structures may be used for this purpose. Restorations made with multilayering techniques may better mimic natural teeth. This study assessed the impact of different materials and application methods on the stress state of CAD/CAM endocrowns. To this end, a 3D FEM model simulating an endodontically treated mandibular first molar was elaborated. The sample was then modified to imitate the ceramic endocrown-applied molar tooth. Three FEM models were then developed from this main model to simulate the following endocrown structures: (1) lithium disilicate reinforced glass ceramic, (2) monolithic zirconia, and (3) multilayered glass ceramic and glass-fiber endocrown (i.e., a glass-fiber core structure and glass ceramic crown). The SolidWorks/Cosmosworks software packages were used for structural analysis. The materials used in the study were treated as homogeneous and isotropic. A 300 N load was applied to the occlusal surfaces of the restored teeth. The von Mises stresses were calculated at the cavity base, ranging from 0.417-0.700 MPa, 0.600-0.850 MPa, and 0.083-0.250 MPa, respectively. The multilayering technique provided the lowest stresses and stress distributions comparable with the natural tooth model. Models of teeth restored with zirconia endocrowns showed the highest stresses and were the least applicable in dental pracice.