Influence of cement type on the marginal adaptation of all-ceramic MOD inlays.

OBJECTIVE: The aim of this study was to investigate the in-vitro marginal adaptation of all-ceramic class II inlays which were luted with conventional multi-stage pre-treatment cements and one new type of cement, which requires no conditioning. METHODS: The marginal adaptation of 56 all-ceramic inlays was determined with scanning electron microscopy and microleakage tests. The marginal integrity of each tooth was evaluated at cement-dentin and cement-enamel junctions, with regard to the transitions between tooth-cement and cement-inlay. The inlays were luted on human molars with two resin cements, one compomer, one resin modified glass-ionomer and one new resin cement in accordance with the manufacture's recommended pre-treatment. Light- and chemical-curing modifications were investigated. All tests were performed after thermal cycling and mechanical loading (TCML). RESULTS: For the resin cements and the new material the marginal integrity was higher than 90% before and after TCML. The marginal adaptation was between 55-80% for the resin modified glass-ionomer and lower than 20% for the compomer. The microleakage was lower than 20% for all cements, only the compomer showed values up to 100% penetration. SIGNIFICANCE: The difference in marginal integrity between the new universal resin cement without any tooth pre-treatment and conventional resin cements after total-etching, priming and bonding was not significant. Resin GIC may be used with restrictions and compomer cement should not be used with all-ceramic class II inlay restorations.     

Comparison of three types of fiber-reinforced composite molar crowns on their fracture resistance and marginal adaptation

Three types of fiber-reinforced composite (FRC) molar crowns were tested on their fracture resistance and marginal adaptation under simulated oral stress conditions. Two glass fiber systems, one processed with a vacuum/pressure system, the other by manual fiber adaptation, and a polyethylene fiber system were evaluated. Every group consisted of 12 crowns.All crowns were luted adhesively on human molars and exposed to thermal cycling and mechanical loading (TCML: 6000 x 5 degrees C/55 degrees C; 1.2 x 10(6) x 50N; 1.66Hz). The marginal adaptation was evaluated through dye-penetration and analyzed semi-quantitatively with a scanning electron microscope. The fracture resistance was measured using a Zwick universal testing machine.The highest fracture resistance was observed on the glass-fiber systems (FibreKor/Sculpture 1875N +/- 596; Vectris/Targis 1726+/-542), though statistically, the polyethylene system (belleGlass/Connect 1388+/-620) was not significantly weaker. All systems exceeded the fracture resistance required to withstand the maximum masticatory forces expected in the molar region. The marginal adaptation generally had a tendency towards larger gaps after TCML. The crown/composite-cement bond deteriorated significantly after TCML with the manual fiber adaptation and the polyethylene fiber system. The cement/tooth bond strength depended on which composite-cement/dentin-adhesive system was used. CONCLUSION: The fracture resistance of molar crowns made of glass-fiber reinforced composite was higher than those of polyethylene fiber-reinforced composite crowns. However, there was no statistically significant difference. The marginal adaptation seems to depend on the fiber systems and composite-cement/dentin adhesive system used.     

The effect of cement type and mixing on the bi-axial fracture strength of cemented aluminous core porcelain discs.

OBJECTIVES: Luting agents in current use include zinc phosphate, zinc polycarboxylate, conventional glass-ionomer, resin-modified glass-ionomer and resin composite cements. Dental cements may be used in practice with a wide range of mixing ratios. Accordingly, the impact of cement type and mixing on the strength of alumina reinforcing porcelain was investigated. METHODS: Standard Vitadur-N core porcelain disc specimens were coated with different cement types of varying mixing ratios to produce a luting thickness. Sets of 25 coated specimens were stored at 37+/-1 degrees C for 24h prior to testing. Mean fracture strengths, standard deviations and associated Weibull Moduli (m) were determined using bi-axial fracture (ball-on-ring). RESULTS: The strength data for porcelain discs coated with different cement types manipulated at the consistency indicated for luting all-ceramic crowns showed little variation in magnitude and consistency. The plots of survival probability against strength for specimens coated with acid-base cements appear to develop a slight asymmetry at the lower values of strength. This effect was more pronounced for acid-base cements prepared at mixing ratios below that recommended for luting purposes. SIGNIFICANCE: The corrosive acidic environment of acid-base cements may have extended pre-existing flaws in the porcelain discs producing the asymmetry in the survival distributions. Resin composite cements appear to enhance the strength of the porcelain disc specimens possibly by healing the surface imperfections. This may increase their scope of application over acid-base cements to include the luting of all-ceramic restorations.     

In vitro push-out strength of seven luting agents to dentin

PURPOSE: New luting agents, described as resin-modified glass-ionomer cements and compomers, have been developed during the last decade to improve the retention of cemented restorations. The aims of this study were to (1) compare the push-out strength of these new luting materials against both conventional cements and bonding luting agents, and (2) evaluate the influence of dentin surface treatment on both glass-ionomer cement and 4-META adhesive resin push-out strength. MATERIALS AND METHODS: Conical standardized cavities were drilled in the center of coronal dentin disks. Ninety sandblasted Ni-Cr inlays, divided into nine batches, were luted into the cavities according to the surface treatment and the nature of the following luting agents: zinc phosphate cement, zinc polycarboxylate cement, type 1 glass-ionomer +/- polyacrylic acid, resin-modified glass-ionomer, polyacid-modified composite resin, filled bis-GMA phosphate ester resin, and 4-META adhesive resin +/- application of activated monomer. Each specimen was placed in a holding device, and a steel rod was used to apply a force on the inlay until rupture occurred. The push-out strength was calculated, and the failure mode was controlled. RESULTS: There were significant differences between some of the groups. The highest push-out strength was achieved by the 4-META adhesive resin after application of activated monomer. The lowest value was attained with zinc phosphate and polycarboxylate cements. CONCLUSION: Both resin-modified glass-ionomer and polyacid-modified composite resin luting materials exhibited a push-out strength similar to resin-based materials. Specific dentin surface treatments significantly enhanced the push-out strengths of glass-ionomer cement and 4-META adhesive resin.     

The influence of luting cement on the probabilities of survival and modes of failure of cast full-coverage crowns.

OBJECTIVES: This study compares the probabilities of survival and modes of failure of cast full-coverage crowns bonded with five cements when subjected to tensile pull-off testing. METHODS: Five groups of 25 sound human premolar teeth were prepared for full-coverage crowns, impressions recorded and customized castings fabricated in Ni-Cr-Mb bonding alloy. The cements tested were zinc phosphate, a hand-mixed and capsulated conventional glass-ionomer cement, a resin-modified glass-ionomer cement and a resin composite luting cement. The cemented crowns were stored in water at 37 degrees C for 24 h prior to application of a tensile pull-off force at a strain rate of 10 mm/min. The loads at failure were ranked and modelled by derived Weibull functions each describing the probability of a given specimen failing under a given load. Non-parametric statistical analysis was also applied to the results. RESULTS: There were no significant differences between the loads at failure of zinc phosphate cement, the hand-mixed or the capsulated glass-ionomer cements. The resin-modified glass-ionomer cement and the resin composite cement failed at significantly higher loads than the other three cements, but were not significantly different from each other. The Weibull modulus ranking for each cement from highest to lowest was resin composite = zinc phosphate, resin-modified glass-ionomer, hand-mixed conventional glass-ionomer and capsulated conventional glass-ionomer cement. SIGNIFICANCE: Weibull analysis allows dentists to compare the probability of survival of a crown bonded with different cements at a chosen load giving an indication of cement reliability.     

Marginal adaptation and microleakage of Procera AllCeram crowns with four cements

PURPOSE: This study investigated the effect of different cements on microleakage and marginal adaptation of porcelain crowns. MATERIALS AND METHODS: Eighty extracted molars were divided into two groups. Teeth in one group were prepared to receive Procera AllCeram crowns, whereas the other group was prepared to receive metal-ceramic crowns. Copings were made following standard techniques, and groups were divided for cementation with zinc phosphate, glass-ionomer, resin-modified glassionomer, or resin cement. Specimens were subjected to thermocycling prior to microleakage testing, then sectioned. Microleakage was scored using a five-point scale; marginal adaptation was assessed with a traveling microscope. RESULTS: A significant association was found between cement type and degree of microleakage. With zinc phosphate, 76% of Procera AllCeram and 90% of metal-ceramic copings exhibited extensive microleakage. With glass-ionomer, 49% of Procera AllCeram and 66% of metal-ceramic copings had 0 microleakage scores; with resin-modified glass-ionomer, 10% of Procera AllCeram and 84% of metal-ceramic copings had 0 microleakage scores. With resin cement, 34% of Procera AllCeram and 96% of metal-ceramic copings exhibited 0 microleakage. Procera AllCeram copings had a significantly larger mean marginal gap (54 microm) compared to metal ceramic (29 microm). CONCLUSION: In both types of crowns, the use of resin cement resulted in the highest percentage of 0 microleakage scores, whereas the zinc phosphate cement resulted in the highest percentage of extensive microleakage.     

Microleakage and marginal gap of adhesive cements for noble alloy full cast crowns

Very limited comparative information about the microleakage in noble alloy full cast crowns luted with different types of adhesive resin cements is available. The purpose of this study was to evaluate the microleakage and marginal gap of two self-adhesive resin cements with that of other types of adhesive luting cements for noble alloy full cast crowns. Fifty noncarious human premolars and molars were prepared in a standardized manner for full cast crown restorations. Crowns were made from a noble alloy using a standardized technique and randomly cemented with five cementing agents as follows: 1) GC Fuji Plus resin-modified glass ionomer cement, 2) Panavia F 2.0 resin cement, 3) Multilink Sprint self-adhesive resin cement, 4), Rely X Unicem self-adhesive resin cement with pretreatment, and 5) Rely X Unicem with no pretreatment. The specimens were stored in distilled water at 37°C for two weeks and then subjected to thermocycling. They were then placed in a silver nitrate solution, vertically cut in a mesiodistal direction and evaluated for microleakage and marginal gap using a stereomicroscope. Data were analyzed using a nonparametric Kruskal-Wallis test followed by Dunn multiple range test at a p<0.05 level of significance. The Rely X Unicem (with or with no pretreatment) exhibited the smallest degree of microleakage at both tooth-cement and cement-crown interfaces. The greatest amount of microleakage was found for Panavia F 2.0 resin cement followed by GC Fuji Plus at both interfaces. No statistically significant difference in the marginal gap values was found between the cementing agents evaluated (p>0.05). The self-adhesive resin cements provided a much better marginal seal for the noble alloy full cast crowns compared with the resin-modified glass ionomer or dual-cured resin-based cements.     

Fracture resistance and marginal adaptation of conventionally cemented fiber-reinforced composite three-unit FPDs

PURPOSE: This in vitro study investigated the marginal adaptation and fracture resistance of three-unit fiber-reinforced composite fixed partial dentures (FPD) luted with two different resin-modified glass-ionomers. MATERIALS AND METHODS: A total of 48 FPDs were constructed from the glass fiber-reinforced materials FibreKor/Sculpture, Vectris/Targis, or the polyethylene fiber system BelleGlass/Connect (n = 16 for each brand). The reconstructions were conventionally luted on human molars using resin-modified ProTecCEM or Fuji Plus and then exposed to thermocycling and mechanical loading. RESULTS: During thermocycling and mechanical loading, cementation failed in seven of eight FibreKor or BelleGlass FPDs and in one of eight Vectris/Targis FPDs luted with ProTecCEM. All Fuji Plus-cemented FPDs showed no signs of damage or cementation loss. The fracture resistance of the remaining FPDs was as follows: Vectris/Targis-ProTecCem 1,361 +/- 360 N, Vectis/Targis-Fuji Plus 923 +/- 207 N, BelleGlass/Connect 940 +/- 155 N, and FibreKor/Sculpture 524 +/- 202 N. The marginal adaptation of the cement-tooth interface deteriorated by 13% to 21% for all reconstructions after stress application, which was not statistically significant. The crown-cement interface had a significantly greater marginal gap only with the combination of FibreKor and Fuji Plus after stress simulation (change 33%). CONCLUSION: Conventional cementation of fiber-reinforced FPDs can lead to cementation loss. The marginal adaptation and fracture resistance deteriorated in comparison to adhesively cemented reconstructions.     

In vitro fracture resistance and marginal adaptation of metallic and tooth-coloured post systems

The aim of this in vitro study was to compare the fracture resistance and marginal adaptation of all-ceramic incisor crowns with all-ceramic posts, glass-fibre-reinforced posts and titanium posts as well as a control without any post. Three groups of eight maxillary incisors were restored with an all-ceramic post, a fibre-reinforced composite (FRC) post, a titanium post and a further group was restored without posts. Composite cores were provided and all-ceramic crowns were adhesively luted. After artificial ageing, the fracture resistance of the restored teeth was determined. The marginal adaptation of the restorations at the interfaces between cement-tooth and cement-crown was evaluated with scanning electron microscopy using replica specimen before and after ageing. The restored teeth without posts [270N (235/335)] showed no significantly different fracture strength compared with teeth with the titanium system [340N (310/445)]. The all-ceramic posts [580N (425/820)] and the FRC posts [505N (500/610)] both provided a significant higher fracture resistance than the teeth without posts. Prior to ageing, all materials showed <5% separation at the margins cement-tooth or cement-crown ('marginal gap'). After ageing, the interfaces of all systems deteriorated to values between 6 and 14% marginal gap. The greatest marginal gap was found with the titanium system (14%) at the interface cement-crown and with the all-ceramic posts (12%) at the transition between cement-tooth. Regarding fracture resistance and the marginal adaptation, the all-ceramic and FRC posts may be considered as an alternative to the commonly used titanium post restorations.     

Marginal leakage around V-shaped cavities restored with glass-ionomer cements: an in vitro study.

The object of this investigation was to assess the degree of marginal leakage around V-shaped cervical glass-ionomer cement restorations and compare it to that around composite resin restorations. Three different glass-ionomer cements and one composite resin control were assessed by means of dye penetration. Severe microleakage at the occlusal margins was found in 70% of the glass-ionomer cement restorations, but in only 10% of the composite resin restorations. A considerable amount of dye penetration was observed at the cervical margins of all restorations, including the controls. None of the glass-ionomer cements tested showed superiority in preventing marginal leakage occlusally or gingivally.     

Short-term clinical evaluation of a resin-modified glass-ionomer luting cement.

OBJECTIVES: Resin-reinforced glass-ionomer cements were developed by adding resin components to conventional glass-ionomer cement. This improved physical properties and bonding characteristics. FujiCEM is the first paste-paste-type resin-modified glass-ionomer luting cement that enables consistent mixture. The purpose of this study was to evaluate the short-term clinical performance of FujiCEM, which was used for final cementation of indirect restorations, such as inlays, crowns, and fixed partial dentures. METHOD AND MATERIALS: A total of 290 restorations (165 crowns, 71 inlays, 15 onlays, 36 fixed partial dentures, 3 implant superstructures) were placed in 268 patients (137 males, 131 females) with a mean age of 54.4+/-13.0 years. Restorations were luted with FujiCEM mixed for 10 seconds after the teeth surfaces were treated with a conditioner containing 10% citric acid and 2% ferric chloride for 20 seconds, washed, and dried with gentle air flow. Out of the investigated 337 teeth, 99 (29%) teeth were vital, and 238 (71%) were nonvital. These restorations were followed up for a period of 21 months. All the restorations were evaluated for postoperative sensitivity, secondary caries, gingival condition, and pocket depth. RESULTS: No clinical failures (eg, dislodgment, secondary caries, irritation of soft tissue, and postoperative sensitivity) were observed. CONCLUSION: FujiCEM had promising clinical performance with inlays, crowns, onlays, fixed partial dentures, and implant superstructures at 21 months after service.     

Load fatigue of compromised teeth: a comparison of 3 luting cements

PURPOSE: This study compared the number of cycles to failure of central incisors restored with full cast crowns and then cemented with 3 different luting cements. MATERIALS AND METHODS: Fifteen human maxillary central incisors received cast post-and-core restorations. These were cemented with zinc phosphate. The teeth were then divided into 3 groups of 5 samples each. Each tooth had a ferrule length of 1.0 mm and was prepared for a full crown. A waxing jig was used to standardize the load application point on all waxed crowns. Complete cast crowns were cemented to the compromised teeth using 3 different luting cements: a zinc phosphate cement (control group), a resin-modified glass-ionomer cement, and a resin cement with a dentin bonding agent. A fatigue load of 1.5 kg was applied at a rate of 72 cycles per minute until failure of the cement layer occurred between the crown and the tooth (preliminary failure). The independent variable was the number of load cycles required to create preliminary failure. An electrical resistance strain gauge was used to provide evidence of preliminary failure. RESULTS AND CONCLUSION: The resin cement samples had a significantly higher number of load cycles to preliminary failure than both the zinc phosphate and the resin-modified glass ionomer (P < or = 0.05). There was no significant difference between the zinc phosphate and the resin-modified glass-ionomer cements.     

Marginal adaptation of direct composite and sandwich restorations in Class II cavities with cervical margins in dentine

OBJECTIVES: The aim of this study was to evaluate the marginal adaptation of direct Class II sandwich restorations with resin-modified glass-ionomer cements and compomers in comparison to base and total bond restorations. For sandwich restorations with a triple cure resin-modified glass-ionomer cement the influence of different light curing techniques was also evaluated. METHODS: Large butt-joint class II cavities with cervical margins 1 mm below the cemento-enamel junction were cut into 120 extracted human molars. The cavities (15 groups, n = 8) were filled using a sandwich, base or total bond technique with materials from five different manufacturers. A three-sited light curing technique was used in 13 groups. For the material combination Vitremer/Z100 two additional groups with a different wand positioning and a metal matrix were evaluated. After water storage for 21 days and thermocycling (2000x, 5-55 degrees C), replicas were quantitatively analysed in the SEM. Statistical analysis was performed with the Kruskal-Wallis test and the Bonferroni test at p < 0.05. RESULTS: The marginal adaptation of vertical enamel margins was not dependent on the restorative technique. For margins in dentine, marginal adaptation was significantly better with the sandwich technique than with a base or total bond technique for all materials. There were no significant differences between the base and total bond technique. Overall, resin-modified glass-ionomer cements showed somewhat better results than compomers in sandwich restorations, though differences were not significant for some criteria. Vitremer/Z100 sandwich restorations applied with a metal matrix showed the highest mean percentage of excellent margins of all experimental groups. CONCLUSIONS: Both resin-modified glass-ionomer cements and compomers can improve the marginal quality when used in a sandwich technique. Further research is necessary to determine the ideal material combination for sandwich restorations.     

Clinical evaluation of Procera AllCeram crowns in the anterior and posterior regions

The aim of this prospective clinical study was to investigate the long-term survival of Procera AllCeram all-ceramic crowns in the anterior and posterior regions. Between 1997 and 2005, 155 Procera crowns with aluminum oxide cores were placed in 50 patients. Patients were recalled in 2005 for a clinical assessment. Thirty-nine patients with 135 crowns attended the recall examination. Of the 135 total crowns, 103 were located in the posterior region and 32 were located in the anterior region. The cumulative survival rate was 100% in the anterior region and 98.8% in the posterior region (1 crown fracture) after 5 and 7 years. Clinical success was achieved irrespective of the tooth position, cement used (resin composite or glass-ionomer cement), or the core design with reduced or conventional margins. Procera AllCeram seems to be a predictable technique for esthetic all-ceramic single crown restorations in the anterior and posterior regions.     

Critical Appraisal

Many dentists still view zinc phosphate as the "gold standard" for luting cast and porcelain-fused-to-metal restorations. Introduced in 1879, zinc phosphate cement has withstood the test of time and gained a reputation for reliability despite its nonadhesive qualities and association with postcementation sensitivity when handled improperly. Hewer classes of luting cements have been introduced, including polycarboxylate, glass ionomer, resin-reinforced (resin-modified) glass ionomer, and resin composite. Several of these materials have advantages over zinc phosphate, including adhesion to alloys and tooth structure, fluoride release, and improved physical properties. Conversely, they also exhibit some disadvantages, such as higher cost, complex handling requirements, and adhesive qualities that can make retrieval of castings impossible. This "Critical Appraisal" reviews recent articles dealing with newer luting cements in an effort to give readers some assistance in their selection and use.
Two publications address the effect of handling and manipulation variables on the physical properties of various cements. Another in vitro investigation highlights the margin sealing effect of resin-modified glass ionomer composite (GIC) with and without saliva contamination. Finally, a large retrospective study reports clinical outcomes of anterior and posterior alumina core all-ceramic crowns luted with a resin-modified GIC. The significance of each publication is discussed below.     

Bonding to densely sintered alumina surfaces: effect of sandblasting and silica coating on shear bond strength of luting cements

PURPOSE: An important determinant of the clinical success of ceramic restorations is the bond strength of the luting agent to the seating surface and the prepared tooth structures. Manufacturers of ceramic systems frequently specify both the luting agent and preluting treatment of the seating surface of the crown. Procera AllCeram is an all-ceramic crown comprising a porcelain-veneered coping of densely sintered, high-purity aluminum oxide. This study evaluated the shear bond strength of 4 luting agents: zinc-phosphate, glass-ionomer, resin-modified glass-ionomer, and resin cement (dual cured) to Procera aluminum oxide coping material. The luting agents were subjected to different surface treatments: untreated, sandblasted, or silica coated by the Rocatec system. MATERIALS AND METHODS: Cylindric and cubic specimens of the coping material were luted together, and the shear force necessary to separate the cylinder from the cube was measured with a universal testing machine. The surfaces of the specimens were also analyzed. RESULTS: No significant differences were recorded for the shear bond strengths of the luting agents to the untreated aluminum oxide. Glass-ionomer and the resin-modified glass-ionomer cements had the highest values (4.2 +/- 2.5 MPa and 4.3 +/- 1.9 MPa, respectively), and the lowest were 3.3 +/- 2.3 MPa for the resin cement and 3.2 +/- 1.0 MPa for the zinc-phosphate cement. Similar results were recorded for the sandblasted aluminum oxide surfaces, except with the glass-ionomer, which was significantly higher (12.9 +/- 2.4 MPa). For all 4 luting agents, the highest shear bond strength values were recorded for the silica-coated specimens; the highest was for the resin cement, at 36.2 +/- 7.8 MPa. CONCLUSION: The bond strengths between resin cement and aluminum oxide specimens treated by the Rocatec system were significantly higher than those of the other materials and surface treatments evaluated.     

Fracture strength of 5 different all-ceramic crown systems

PURPOSE: The purpose of this study was to evaluate the fracture resistance of 5 different all-ceramic crown systems (In-Ceram, Empress staining technique, Empress veneering technique, Celay feldspathic system, and Celay In-Ceram system) before and after cyclic preloading in an artificial mouth. MATERIALS AND METHODS: Extracted natural maxillary incisors were prepared with a 90-degree shoulder. The crowns were adhesively luted to the abutments using dual-cured composite cement. Half of the specimens were artificially aged via a chewing simulation and thermocycling, and all specimens were tested for fracture strength. The results were compared with those of porcelain-fused-to-metal (PFM) crowns with circular porcelain-butt margins that were cemented with zinc phosphate cement. RESULTS: The chewing simulation and the thermocycling significantly decreased the fracture strength of all tested crown systems (P < 0.01). There were no statistically significant differences between the all-ceramic crown groups and the PFM crowns. CONCLUSION: All-ceramic crowns can be used for anterior restorations. However, in vivo investigations of all-ceramic crown systems should be undertaken before introducing them into routine clinical use.     

Is adhesive cementation of endodontic posts necessary?

Recently, the appropriate, durable bond of adhesive systems and composite resin cements to retain endodontic posts was challenged. The question arises whether it would be possible to place glass fiber posts in a less technique sensitive conventional nonadhesive approach. The influence of nonadhesive, self-adhesive, and etch-and-rinse systems on load capability of postendodontic restorations was studied. Human maxillary central incisors were divided into 4 groups (n = 10). Teeth were endodontically treated and restored by using glass fiber posts luted with different cements/composite resin combinations: (1) RelyX Unicem (3M ESPE, Seefeld, Germany)/Clearfil Core (Kuraray Europe, Duesseldorf, Germany), (2) RelyX Unicem/LuxaCore, (3) zinc phosphate cement/Clearfil, and (4) LuxaCore (DMG, Hamburg, Germany)/Clearfil. A 2 mm-ferrule preparation was performed. All specimens received adhesively luted all-ceramic crowns and were exposed to thermal cycling and mechanical loading before subsequent static loading. Significant differences between the experimental groups regarding load capability and fracture patterns were observed. The conventional non-adhesive post cementation is less reliable to withstand simulated functional forces compared to adhesive approaches.     

Fracture resistance of crowned incisors with different post systems and luting agents

This study evaluated the fracture resistance of crown-restored incisors with different post-and-core systems and luting cements. Fifty intact maxillary central incisors were randomly assigned to five groups of 10 teeth each. Group 1 was restored with fibre posts (Snowpost) luted with an adhesive composite resin cement (Panavia F). Group 2 was restored with titanium alloy posts (Parapost) luted with the resin cement, and Group 3 with titanium alloy posts and a glass-ionomer cement (Fuji I). Composite cores (Clearfil Photocore) were built up in groups 1, 2 and 3. Group 4 was restored with cast post-and-cores luted with the resin cement, and group 5 with the cast post-and-cores and the glass-ionomer-cement served as a control group. All teeth were restored with metal-ceramic crowns. After thermal stressing, the specimen was then secured in a universal testing machine. Fracture loads and modes were recorded. One-way ANOVA and a Tukey test were used to determine significant differences between the failure loads of groups. Chi-square test was conducted for evaluation of the fracture modes. The fracture loads of groups 1 and 2 were significantly higher than that of the control group (P<0.05). Group 1 had a significantly higher number of repairable fractures than the other four groups (P<0.001). Within the limitations of this study, the results suggest that fibre posts can be recommended as an alternative to cast and prefabricated metallic posts. Composite resin cement cannot significantly improve fracture resistance of metallic post and crown-restored incisors.