Comparison of fiber reinforcement placed at different locations of pontic in interim fixed partial denture to prevent fracture: An in vitro study

Background:

The interim restoration is an important phase in fixed prosthodontic therapy. It should provide sufficient durability to withstand the forces of mastication. A fractured interim restoration is damaging to the prosthodontic care and may lead to an unscheduled appointment for repair. Several attempts have been made to reinforce interim fixed partial dentures (FPDs). These have included the use of metal wire, a lingual cast metal reinforcement, a processed acrylic resin interim restoration, and different types of fibers, e.g., carbon, polyethylene, nylon and glass. These fibers can be placed in the occlusal, middle or cervical thirds in the FPD. There is no scientific data to evaluate the effect of fiber placement methods on the fracture resistance of clinical interim FPDs.

Purpose of the Study:

Hence this study was designed to evaluate fracture load values of interim FPDs with different locations of fiber reinforcement.

Materials and Methods:

30 interim FPD samples with polymethyl methacrylate (PMMA) reinforced with fibers at three different locations mainly occlusal, cervical and middle (10 samples each) were fabricated using a metal FPD on a master die. They were tested for fracture resistance in universal testing machine.

Results:

The fracture resistance was recorded and is tabulated and analyzed statistically. The results showed that the placement of the reinforcement in the occlusal third of the pontic resulted in higher fracture resistance which was significantly higher (P < 0.05) than all other locations.

Conclusion:

The occlusal third of the pontic region from mesial to the distal end of the connector is the best site of placement of the fiber for reinforcing the PMMA interim restorative resin.Key Words: Fiber placement, fracture resistance, interim fixed partial denture, polymethyl methacrylate, reinforcements     

Evaluation of fracture resistance of inlay-retained fixed partial dentures fabricated with different monolithic zirconia materials

Statement of problem

Data are lacking on the fracture resistance of monolithic zirconia inlay-retained fixed partial dentures as a conservative treatment for a single missing tooth.

A study on the fracture strength of collarless metal-ceramic fixed partial dentures

PURPOSE

The objective of this study was to evaluate fracture strength of collarless metal-ceramic FPDs according to their metal coping designs.

MATERIALS AND METHODS

Four different facial margin design groups were investigated. Group A was a coping with a thin facial metal collar, group B was a collarless coping with its facial metal to the shoulder, group C was a collarless coping with its facial metal 1 mm short of the shoulder, and group D was a collarless coping with its facial metal 2 mm short of the shoulder. Fifteen 3-unit collarless metal-ceramic FPDs were fabricated in each group. Finished FPDs were cemented to PBT (Polybutylene terephthalate) dies with resin cement. The fracture strength test was carried out using universal testing machine (Instron 4465, Instron Co., Norwood MA, USA) at a cross head speed of 0.5 mm/min. Aluminum foil folded to about 1 mm of thickness was inserted between the plunger tip and the incisal edge of the pontic. Vertical load was applied until catastrophic porcelain fracture occurred.

RESULTS

The greater the bulk of unsupported facial shoulder porcelain was, the lower the fracture strength became. However, there were no significant differences between experimental groups (P > .05).

CONCLUSION

All groups of collarless metal-ceramic FPDs had higher fracture strength than maximum incisive biting force. Modified collarless metal-ceramic FPD can be an alternative to all-ceramic FPDs in clinical situations.     

Framework design and pontics of fiber-reinforced composite fixed dental prostheses — An overview

Purpose

Fiber-reinforced composite (FRC) fixed dental prostheses (FDPs) have shown good performance in clinical applications due to their good mechanical properties and minimally invasive approach. However, typical failure patterns of FRC FDPs are often localized at the pontic site. That reflects the structural considerations at the framework and pontic location that need to be examined when creating these kinds of prostheses.

Fixed partial dentures in an up to 8-year follow-up

Information on the longevity of fiber-reinforced composite fixed partial dentures (inlay FPDs) should be considered in the selection of materials, operative techniques and patient instructions related to prognosis and long-term cost-effectiveness.

Objective

This study evaluated the long-term survival of fiber-reinforced, adhesively-bonded composite prostheses placed in posterior teeth.

Material and Methods

Twenty-one patients that received adhesively bonded polyethylene inlay FPDs in posterior teeth were selected from a private practice dental office and invited to evaluation. Of the eligible 21 patients, 13 (mean age 50.3 ±11.5 years) agreed to be enrolled as participants, providing 22 restorations, as several subjects presented more than one inlay FPD. One dentist placed all inlay FPDs using Ribbond as reinforcement and Tetric Ceram/Durafil or Charisma/Renamel composite combinations, according to manufacturer’s instructions. Two independent calibrated operators performed the evaluation, using modified USPHS criteria. Survival functions of restorations were analyzed with Kaplan-Meier and Log Rank test (α = 0.05).

Results

The majority of restorations received A or B scores. Four (18.2%) inlay FPDs fractured among the 22 evaluated. The mean estimate survival rate was 7 years (95% CI: 5.9 to 8.1), and the overall percentage of survival was 81.8%. There were no significant differences (p>0.05) between composite combinations or tooth location considering all clinical aspects evaluated and survival functions.

Conclusion

Posterior fiber-reinforced fixed partial dentures exhibited acceptable clinical performance after a period up to 8 years.     

Effect of different ferrule designs on the fracture resistance and failure pattern of endodontically treated teeth restored with fiber posts and all-ceramic crowns

Objective

This study investigated the effect of different ferrule heights on endodontically treated premolars.

Materials and Methods

Fifty sound mandibular first premolars were endodontically treated and then restored with 7-mm fiber post (FRC Postec Plus #1 Ivoclar-Vivadent) luted with self-polymerized resin cement (Multilink, Ivoclar Vivadent) while the coronal section was restored with hybrid composite core build-up material (Tetric Ceram, Ivoclar-Vivadent), which received all-ceramic crown. Different ferrule heights were investigated: 1-mm circumferential ferrule without post and core (group 1 used as control), a circumferential 1-mm ferrule (group 2), non-uniform ferrule 2-mm buccally and 1-mm lingually (group 3), non-uniform ferrule 3-mm buccally and 2-mm lingually (group 4), and finally no ferrule preparation (group 5). The fracture load and failure pattern of the tested groups were investigated by applying axial load to the ceramic crowns (n=10). Data were analyzed statistically by one-way ANOVA and Tukey’s post-hoc test was used for pair-wise comparisons (α=0.05).

Results

There were no significant differences among the failure load of all tested groups (P<0.780). The control group had the lowest fracture resistance (891.43±202.22 N) and the highest catastrophic failure rate (P<0.05). Compared to the control group, the use of fiber post reduced the percentage of catastrophic failure while increasing the ferrule height did not influence the fracture resistance of the restored specimens.

Conclusions

Within the limitations of this study, increasing the ferrule length did not influence the fracture resistance of endodontically treated teeth restored with glass ceramic crowns. Insertion of a fiber post could reduce the percentage of catastrophic failure of these restorations under function.     

Mandibular Third Molar Position Influencing the Condylar and Angular Fracture Patterns

Purpose

The aim of this study was to assess the influence of position of mandibular 3rd molar on angle and condylar fractures.

Materials and Methods

Panoramic radiographs were used to determine the mandibular fracture patterns based on the presence or absence of the third molar.

Results

Of the 64 patients with mandibular fractures, condyle and angle fractures were found to be 67 and 33 % respectively. The greatest percentage (75 %) of condylar fractures were associated with erupted third molar teeth, and 25 % had impacted teeth. Subcondylar region was found to be the most common site that predisposes to fracture. Moderate force lead to condylar fracture when third molar is erupted or absent and mild force showed angle fracture when third molar is impacted. Increased incidence of angle fracture was observed when tooth is in mesioangular and distoangular position.

Conclusion

Impacted mandibular 3rd molar leads to an increased risk of angle fracture and decreased risk of condylar fracture especially when they are more deeply seated.     

Eruption Status of Third Molar and Its Possible Influence on the Location of Mandibular Angle Fracture: A Retrospective Analysis

Introduction

This study was designed to evaluate the influence of eruption status of mandibular third molars on the location of mandibular angle fracture. We also aimed to evaluate the incidence of damage to mandibular third molar teeth (M3) and its roots.

Materials and Methods

Medical records and panoramic radiographs of 142 patient cohorts with mandibular angle fractures with third molars present were retrospectively reviewed.

Results

Revealed that incidence of angle fracture were high in patients with fully erupted M3 when compared to unerupted group. Out of 142 patients, 108 fractures were found involving the M3 socket and 14.1 % had damage to M3.

Conclusion

The presence of erupted mandibular third molar increases the chances of angle fracture when compared to impacted M3. Involvement of the M3 socket often resulted in increased operative time and complexity of the surgical procedure with possible removal of the damaged M3.     

The Effect of Repeated Microwaving Disinfection on the Dimensional Stability of Acrylic Dentures

Objective

The aim of this study was to evaluate the effect of repeated microwave disinfections on the dimensional stability of acrylic dentures.

Materials and Methods

Three groups of dentures made of a heat polymerized acrylic resin were tested. I: dentures kept in water (control group). II: dentures microwaved daily while being immersed into water (wet disinfection). III: dentures microwaved daily without being immersed into water (dry disinfection).
Measurements were taken across three reference points, on two occasions: after curing and immersion in water for 24 hours, and one week later.
Data obtained were analyzed using one-way analysis of variance (ANOVA) and Scheffe’s multiple range test.

Results

The results showed that the microwave disinfection provokes dimensional changes of the same pattern (shrinkage). The dentures which underwent wet disinfection exhibited the greatest shrinkage (p<0.05).

Conclusions

Disinfection using microwave energy may cause dimensional changes (shrinkage) of complete dentures.
The microwave “dry disinfection” method can be safely applied in everyday practice since the dimensional changes which occurred seem to be of no clinical significance.Key words: Complete Dentures, Acrylic Resins, Disinfection, Microwaves, Dimensional Measurement Accuracy     

Marginal fit of anterior 3-unit fixed partial zirconia restorations using different CAD/CAM systems

PURPOSE

Few studies have investigated the marginal accuracy of 3-unit zirconia fixed partial dentures (FPDs) fabricated by computer-aided design/computer-aided manufacturing (CAD/CAM) system. The purpose of this study was to compare the marginal fit of zirconia FPDs made using two CAD/CAM systems with that of metal-ceramic FPDs.

MATERIALS AND METHODS

Artificial resin maxillary central and lateral incisors were prepared for 3-unit FPDs and fixed in yellow stone. This model was duplicated to epoxy resin die. On the resin die, 15 three-unit FPDs were fabricated per group (45 in total): Group A, zirconia 3-unit FPDs made with the Everest system; Group B, zirconia 3-unit FPDs made with the Lava system; and Group C, metal-ceramic 3-unit FPDs. They were cemented to resin dies with resin cement. After removal of pontic, each retainer was separated and observed under a microscope (Presize 440C). Marginal gaps of experimental groups were analyzed using one-way ANOVA and Duncan test.

RESULTS

Mean marginal gaps of 3-unit FPDs were 60.46 µm for the Everest group, 78.71 µm for the Lava group, and 81.32 µm for the metal-ceramic group. The Everest group demonstrated significantly smaller marginal gap than the Lava and the metal-ceramic groups (P<.05). The marginal gap did not significantly differ between the Lava and the metal-ceramic groups (P>.05).

CONCLUSION

The marginal gaps of anterior 3-unit zirconia FPD differed according to CAD/CAM systems, but still fell within clinically acceptable ranges compared with conventional metal-ceramic restoration.     

Alternate metal framework designs for the metal ceramic prosthesis to enhance the esthetics

PURPOSE

The objective of the present study was to evaluate the effect of five different metal framework designs on the fracture resistance of the metal-ceramic restorations.

MATERIALS AND METHODS

For the purpose of this study, the central incisor tooth was prepared, and the metal analogue of it and a master die were fabricated. The counter die with the 0.5 mm clearance was used for fabricating the wax patterns for the metal copings. The metal copings with five different metal framework designs were designed from Group 1 to 5. Group 1 with the metal collar, Group 2, 3, 4 and 5 with 0 mm, 0.5 mm, 1 mm and 1.5 mm cervical metal reduction respectively were fabricated. Total of fifty metal ceramic crown samples were fabricated. The fracture resistance was evaluated with the Universal Testing Machine (Instron model No 1011, UK). The basic data was subjected to statistical analysis by ANOVA and Student''s t-test.

RESULTS

Results revealed that the fracture resistance ranged from 651.2 to 993.6 N/m². Group 1 showed the maximum and Group 5 showed the least value.

CONCLUSION

The maximum load required to fracture the test specimens even in the groups without the metal collar was found to be exceeding the occlusal forces. Therefore, the metal frameworks with 0.5 mm and 1 mm short of the finish line are recommended for anterior metal ceramic restoration having adequate fracture resistance.     

Vertically Unstable Fractured Mandibular Segment with Attached Genial Tubercles as a Parameter for Difficulty During Intubation for General Anaesthesia

Purpose

It remains vital for the trauma management team including the anaesthetist and the operating surgeon to assess and evaluate the anticipated difficulty in intubation to secure airway and for administration of anaesthesia. This study assesses the difficulty in intubating patients with vertically unstable mandibular parasymphysis fracture with attached genial tubercles and associated musculature to the fractured segment.

Methods

Randomized sampling was done from the cases with maxillofacial trauma planned for a surgical procedure under general anaesthesia. The inclusion criteria was to prospectively identify ten patients each of unilateral unfavourable mandibular parasymphysis fracture with genial tubercle attached to the displaced segment, with bilateral unfavourable mandibular parasymphysis fracture with genial tubercle attached to the displaced segment and with unilateral favourable mandibular parasymphysis fracture with genial tubercle attached to the un-displaced segment. All the patients were intubated by a single anaesthetist, who documented the difficulty in nasoendotracheal intubation using Intubation Difficulty Scale.

Results

Nasoendotracheal intubation was found relatively easy in the study group with unilateral favourable mandibular parasymphysis fracture with genial tubercle attached to the un-displaced segment. Clinical difficulty in intubating the patients was maximum in the study group with bilateral unfavourable mandibular parasymphysis fracture with genial tubercle attached to the displaced segment.

Conclusion

Displacement of fractured mandible and resultant displacement of the genial musculature should be considered as a vital parameter for assessing difficulty during intubation.     

Clinical performance and failures of zirconia-based fixed partial dentures: a review literature

PURPOSE

Zirconia has been used in clinical dentistry for approximately a decade, and there have been several reports regarding the clinical performance and survival rates of zirconia-based restorations. The aim of this article was to review the literatures published from 2000 to 2010 regarding the clinical performance and the causes of failure of zirconia fixed partial dentures (FPDs).

MATERIALS AND METHODS

An electronic search of English peer-reviewed dental literatures was performed through PubMed to obtain all the clinical studies focused on the performance of the zirconia FPDs. The electronic search was supplemented by manual searching through the references of the selected articles for possible inclusion of some articles. Randomized controlled clinical trials, longitudinal prospective and retrospective cohort studies were the focuses of this review. Articles that did not focus on the restoration of teeth using zirconia-based restorations were excluded from this review.

RESULTS

There have been three studies for the study of zirconia single crowns. The clinical outcome was satisfactory (acceptable) according to the CDA evaluation. There have been 14 studies for the study of zirconia FPDs. The survival rates of zirconia anterior and posterior FPDs ranged between 73.9% - 100% after 2 - 5 years. The causes of failure were veneer fracture, ceramic core fracture, abutment tooth fracture, secondary caries, and restoration dislodgment.

CONCLUSION

The overall performance of zirconia FPDs was satisfactory according to either USPHS criteria or CDA evaluations. Fracture resistance of core and veneering ceramics, bonding between core and veneering materials, and marginal discrepancy of zirconia-based restorations were discussed as the causes of failure. Because of its repeated occurrence in many studies, future researches are essentially required to clarify this problem and to reduce the fracture incident.     

A clinical investigation of the relationship between the quality of conventional complete dentures and the patients’ quality of life

Objective

The purpose of this study was to determine whether there is a correlation between the clinical quality of conventional complete dentures and patient quality of life.

Materials and methods

This study included a random sample of 32 completely edentulous patients (15 males and 17 females) who were treated with conventional complete dentures. Using a validated questionnaire, three investigators evaluated the dentures independently on the basis of seven clinical parameters: esthetics (lip support and lower lip line), retention and stability of the maxillary and the mandibular dentures, and occlusion. Patients completed the validated Oral Health Impact Profile-20 (OHIP-20) questionnaire. Correlations were determined by using the point-biserial correlation coefficient.

Results

Clinicians rated the overall clinical quality of the dentures satisfactory in 80.3% of patients. The mean (±standard deviation) total OHIP-20 score was 56.3 ± 15.9 out of a possible 120 maximum. A statistically significant negative correlation was found between the stability of the maxillary and mandibular dentures and the total OHIP-20 score (p = 0.009 and 0.0023, respectively). A negative correlation between the total OHIP-20 score and the retention of the mandibular denture approached significance (p = 0.092). Esthetics, retention of the maxillary denture, and occlusion were not correlated with patient quality of life (p > 0.169).

Conclusion

Stability of the maxillary and mandibular dentures is the denture quality parameter that can most significantly affect patient quality of life.     

Hybrid Implant: A Novel Implant System

Introduction

Replacement of missing tooth has evolved from removable dentures to fixed dentures and recently to dental implants. The need of sufficient bone around the endosseous implant is critical for the success of the implant. The present study was aimed to evaluate the efficacy of a novel implant (HYBRID IMPLANT-submitted for patency) for replacement of the missing teeth.

Materials and methods

1. Research design A prospective research design with a follow up after 1st week ,2nd week ,3rd week,1st month ,3rd month,6th month and 1st year postoperatively. 2. Sampling method Population: All patients who reported for replacement of missing teeth. Inclusion criteria 1. All patients above the age group of 16years 2. Patients who need replacement of single or multiple teeth in the anterior or posterior region of the maxilla and mandible. Exclusion criteria 1. Medically compromised patients. 2. Patients having craniofacial syndromes. 3. Sample size 5 patients were selected taking into consideration the inclusion and exclusion Criteria. Results PAIN All the patients were non symptomatic during the 1st month to 1st year postoperative periods.

Mobility

We experienced mobility during the 1st and 2nd postoperative periods where the implants were inserted in the mandibular molar region.

Bone loss

Radiographic assessment showed no bone loss during the postoperative periods.

Conclusion

The novel implant (hybrid implant) showed good stability and minimum patient discomfort during one year postoperative period evaluation. The implant system leads to new prospect in the field of prosthetic rehabilitation.     

FRACTURE RESISTANCE OF WEAKENED TEETH RESTORED WITH CONDENSABLE RESIN WITH AND WITHOUT CUSP COVERAGE

Objectives:

This in vitro study evaluated the fracture resistance of weakened human premolars (MOD cavity preparation and pulp chamber roof removal) restored with condensable resin composite with and without cusp coverage.

Material and Methods:

Thirty human maxillary premolars were divided into three groups: Group A (control), sound teeth; Group B, wide MOD cavities prepared and the pulp chamber roof removed and restored with resin composite without cusp coverage; Group C, same as Group B with 2.0 mm of buccal and palatal cusps reduced and restored with the same resin. The teeth were included in metal rings with self-curing acrylic resin, stored in water for 24 h and thereafter subjected to a compressive axial load in a universal testing machine at 0.5 mm/min.

Results:

The mean fracture resistance values ± standart deviation (kgf) were: group A: 151.40 ± 55.32, group B: 60.54 ± 12.61, group C: 141.90 ± 30.82. Statistically significant differences were found only between Group B and the other groups (p<0.05). The condensable resin restoration of weakened human premolars with cusp coverage significantly increased the fracture resistance of the teeth as compared to teeth restored without cusp coverage.

Conclusion:

The results showed that cusp coverage with condensable resin might be a safe option for restoring weakened endodontically treated teeth.     

In vivo efficacy of alkaline peroxide tablets and mouthwashes on Candida albicans in patients with denture stomatitis

Objective

Effective cleaning of dentures is important for the maintenance of good oral hygiene for denture stomatitis patients. The in vivo efficacy of three different brands of alkaline peroxide tablets (Polident, Efferdent, and Fittydent) and two mouthwashes (CloSYS II and Corsodyl) to eliminate Candida albicans on dentures was evaluated in this in vivo study.

Material and methods

Ninety denture wearers with clinical evidence of denture stomatitis were randomly divided into 5 test groups and 1 control group. Each group was further divided into three subgroups in which the dentures were subjected to 15-, 30-, and 60-min disinfection procedures. The dentures of each test group were treated with one of the cleaners, while those of the control group were treated with distilled water. Swab samples from the palatal surfaces (2 cm x 2 cm template delimited area) of the upper dentures were obtained before and after 15, 30, and 60 min periods of cleaner use and examined mycologically.

Results

The reduction in the number of colony-forming units (CFU) of C. albicans before, and after 15, 30, and 60 min of use of CloSYS II and Corsodyl was significantly greater than that of the control group (p<0.05). Moreover, there was no statistically significant difference (p>0.05) among Polident, Efferdent and the control group in any of the treatment periods. Dentures treated with Fittydent appeared to have a significantly greater reduction in the number of Candida spp. only after 60 min of treatment.

Conclusions

The results of this study showed that the use of mouthwashes significantly reduced the number of microorganisms on dentures.     

Clinical gap changes after porcelain firing cycles of zirconia fixed dentures

PURPOSE

The aim of this study was to measure the changes on the marginal and internal adaptation of zirconia based anterior fixed partial dentures after the porcelain firing process.

MATERIALS AND METHODS

A total of 34 anterior fixed partial dentures using LAVA CAD/CAM system (3M ESPE, Germany) were applied. Two silicone replicas were obtained: one is obtained before porcelain firing process (initial) and the other is obtained after porcelain firing process (final), followed by the examination under a binocular stereomicroscope. Kruskal Wallis and Wilcoxon Signed Ranks tests were used for the statistical analysis (P<.05).

RESULTS

No statistically significant difference was found between initial and final marginal gap values (P>.05). At the internal gap measurements, final marginal area values (59.54 µm) were significantly lower than the initial marginal area values (68.68 µm)(P<.05). The highest and the lowest internal gap values were observed at the incisal/occlusal area and at the marginal area, respectively. In addition, lower internal gap values were obtained for canines than for central incisors, lateral incisors and premolars at the incisal area (P<.05).

CONCLUSION

The firing cycles did not affect the marginal gap of Lava CAD/CAM system, but it is controversial for the internal gap.     

A QUANTITATIVE ANALYSIS OF ROTARY,ULTRASONIC AND MANUAL TECHNIQUES TO TREAT PROXIMALLY FLATTENED ROOT CANALS

Objective:

The efficiency of rotary, manual and ultrasonic root canal instrumentation techniques was investigated in proximally flattened root canals.

Material and Methods:

Forty human mandibular left and right central incisors, lateral incisors and premolars were used. The pulp tissue was removed and the root canals were filled with red die. Teeth were instrumented using three techniques: (i) K3 and ProTaper rotary systems; (ii) ultrasonic crown-down technique; and (iii) progressive manual technique. Roots were bisected longitudinally in a buccolingual direction. The instrumented canal walls were digitally captured and the images obtained were analyzed using the Sigma Scan software. Canal walls were evaluated for total canal wall area versus noninstrumented area on which dye remained.

Results:

No statistically significant difference was found between the instrumentation techniques studied (p<0.05).

Conclusion:

The findings of this study showed that no instrumentation technique was 100% efficient to remove the dye.     

Biaxial flexural strength of Turkom-Cera core compared to two other all-ceramic systems

Advances in all-ceramic systems have established predictable means of providing metal-free aesthetic and biocompatible materials. These materials must have sufficient strength to be a practical treatment alternative for the fabrication of crowns and fixed partial dentures.

Objectives

The aim of this study was to compare the biaxial flexural strength of three core ceramic materials.

Material and methods

Three groups of 10 disc-shaped specimens (16 mm diameter x 1.2 mm thickness - in accordance with ISO-6872, 1995) were made from the following ceramic materials: Turkom-Cera Fused Alumina [(Turkom-Ceramic (M) Sdn Bhd, Puchong, Selangor, Malaysia)], In-Ceram (Vita Zahnfabrik, Bad Säckingen, Baden-Württemberg, Germany) and Vitadur-N (Vita Zahnfabrik, Bad Säckingen, Baden-Württemberg, Germany), which were sintered according to the manufacturer''s recommendations. The specimens were subjected to biaxial flexural strength test in a universal testing machine at a crosshead speed of 0.5 mm/min. The definitive fracture load was recorded for each specimen and the biaxial flexural strength was calculated from an equation in accordance with ISO-6872.

Results

The mean biaxial flexural strength values were: Turkom-Cera: 506.8±87.01 MPa, In-Ceram: 347.4±28.83 MPa and Vitadur-N: 128.7±12.72 MPa. The results were analyzed by the Levene''s test and Dunnett''s T3 post-hoc test (SPSS software V11.5.0 for Windows, SPSS, Chicago, IL, USA ) at a preset significance level of 5% because of unequal group variances (P<0.001). There was statistically significant difference between the three core ceramics (P<0.05). Turkom-Cera showed the highest biaxial flexural strength, followed by In-Ceram and Vitadur-N.

Conclusions

Turkom-Cera core had significantly higher flexural strength than In-Ceram and Vitadur-N ceramic core materials.