Assessment of LuxaCore, Photo Core, and Core Max II on Fracture Resistance of Endodontically Treated Teeth Restored with ParaPosts and Fiber-Reinforced Composite Posts.

Objectives: The objective is to evaluate the efficacy of LuxaCore, Photo Core, and Core Max II on fracture resistance of endodontically treated teeth restored with ParaPosts and fiber-reinforced composite (FRC) posts. Materials and
Methods: Ninety extracted mandibular first premolar teeth were randomly grouped into nine different groups with ten samples in each. I-FRC posts, II-FRC with Photo Core, III-FRC with LuxaCore, IV-FRC with composite core, V-FRC with Core Max II, VI-para Post (PP), VII-PP with Luxa core, VIII-PP with photo Core, IX-PP with Core Max II were compared for fracture resistance.
Results: The mean fracture resistance (Newton) in group I was 452± 61.5, in group II was 412.6± 42.4 (higher from group I to group V), and lower in group VI to group IX (288 to 246.5). The mean fracture resistance of group II to V was 380.1±72.1 and group VI to IX was 62.8±70.6. The difference was statistically significant (0.001).
Conclusion: FRC posts exhibited higher fracture resistance as compared to ParaPosts, and fracture resistance was not dependent on the type of material used. Copyright:

INTRODUCTION

Restorative dentistry deals with restoring teeth and replacing fractured tooth part. In cases with fractured crown, post, and core restorations can be placed.[12] There are numerous posts available in the market. Metal posts possess higher hardness compared to fiber posts. Fiber-reinforced composite (FRC) has an identical hardness number to that of dentin.[3]

Photo Core is a composite resin with high tensile, compressive, and flexural strength. Its ability to cure in minimum time, nonsticky nature, better curing depth, and easy application makes it the choice of material.[4] In this study, we compared the efficacy of Core Max II, LuxaCore, and Photo Core on fracture resistance of endodontically treated teeth restored with FRC posts and ParaPosts.

MATERIALS AND METHODS

This study was conducted in the Department of Conservative Dentistry and Endodontics. Ninety recently extracted mandibular first premolar teeth were randomly grouped into nine different groups with ten samples in each. I-FRC posts, II-FRC with Photo Core, III-FRC with LuxaCore, IV-FRC with composite core, V-FRC with Core Max II, VI-para Post (PP), VII-PP with Luxa core, VIII-PP with photo Core, IX-PP with Core Max II were compared for fracture resistance.

Following root canal treatment for all teeth, silicone impression material was applied on all roots to simulate the periodontal ligament and was mounted in cubic acrylic molds.

Post space preparation was done using Peeso Reamers (Mani, Tochigi-ken, Japan). Based on the manufacturer's instructions, intracanal posts were cemented into the canal using Panavia F2 resin cement followed by core buildup. The crowns were seated on the teeth in each group. Using universal testing machine, fracture resistance was calculated by applying load at 45° angle to long axis of the tooth at a crosshead speed of 1 mm/min. The point where fracture occurred was recorded with the formula, shear bond strength (MPa) = load (N)/surface area (mm2).

A descriptive statistic was applied based Statistical Package for Social Sciences version 21.0 for Windows (SPSS Inc., Chicago, IL, USA). Student's t-test and one-way analysis of variance were used for comparison between groups, and the level of significance was set below 0.05.

RESULTS

Table 1 shows that the mean fracture resistance (Newton) in Group I was 452 ± 61.5, in Group II was 412.6 ± 42.4, in Group III was 362.4 ± 40.8, in Group IV was 430.4 ± 112.4, in Group V was 384.2 ± 90.6, in Group VI was 288.1 ± 81.5, in Group VII was 240.6 ± 74.2, in Group VIII was 276.4 ± 68.1, and in Group IX was 246.5 ± 50.2. Table 2 shows that the mean fracture resistance of FRC posts with different core materials in Groups II, III, IV, and V was 380.1 ± 72.1 and the mean fracture resistance of ParaPost with different core materials in Groups VI, VII, VIII, and IX was 262.8 ± 70.6. The difference was significant (P < 0.05).

Table 1

Fracture resistance in different groups

Groups	Mean (Newton)±SD	P
Group I	452±61.5	0.001
Group II	412.6±42.4
Group III	362.4±40.8
Group IV	430.4±112.4
Group V	384.2±90.6
Group VI	288.1±81.5
Group VII	240.6±74.2
Group VIII	276.4±68.1
Group IX	246.5±50.2

ANOVA, P<0.05, significance. SD: Standard deviation

Table 2

Comparison of fracture resistance between fiber-reinforced composite post and ParaPost groups

Groups	Mean±SD	Student’s t-test	P
Groups II-V	380.1±72.1	8.2	0.01
Groups VI-IX	262.8±70.6

Student’s t-test, P<0.05, significance. SD: Standard deviation

DISCUSSION

Prefabricated posts have minimized the treatment duration since all procedures can be performed in a single visit. Higher hardness offers better stress distribution, and hardness of posts should be identical to that of dentin.[5] There are factors such as durability, resistance, hardness, and bond strength which can affect the longevity of the reconstructed crown and subsequently the success rate of the prosthetic crown.[6]

Izadi et al. found that maximum fracture resistance (423.7 ± 111.7) was seen with FRC posts + Core Max II with bonding agent, whereas minimum (242.3 ± 73.4) was seen with ParaPosts + LuxaCore. There was no significant difference with the fracture resistance of other groups (P > 0.05).[7] Makade et al. revealed that ParaPost exhibited the highest fracture resistance, whereas the control group showed minimum resistance.[8]

The constraint of this study is small sample size. The variation in results may be due to type of tooth selected. It was in vitro study; hence, further in vivo studies are required with larger samples size and with thermal cycling and fatigue loading for evaluation.

CONCLUSION

FRC posts exhibited higher fracture resistance as compared to ParaPosts, and fracture resistance was not dependent on the type of material used.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.