Clinical Performance of Polyethylene Fiber Reinforced Resin Composite Restorations (Wall Papering Technique) Versus Bulk Fill Resin Composite Restorations in Endodontically Treated Teeth Will be Evaluated Using Modified USPHS Criteria.
Condition: Dental Restoration Failure
MeSH terms: Tooth, Nonvital
Study type: Interventional

Summary: 
      The aim of this study will be to evaluate the clinical performance of polyethylene fiber
      reinforced resin composite restorations versus bulk fill resin composite restorations in
      endodontically treated teeth.
    

Detailed description: 
      Statement of the problem:

      Restoration of non-vital teeth is always challenging for dentists. Without placing the
      coronal restoration, root canal treatments are not considered complete. Appropriate treatment
      plan selection should be based on remaining tooth structure, cavity wall thickness, tooth
      position in the arch, and load applied to the tooth. Previously, endodontically treated teeth
      (ETT) were reconstructed automatically with post, core, and full crown. But this treatment
      plan had many risks like root perforation, sacrificing a considerable amount of sound tooth
      structure, and tooth fracture.Several techniques and materials have been developed for the
      restoration of endodontically treated teeth including complete cast coverage, composite
      resins and amalgam and indirect restorations covering cusps. Resin-based materials provide
      rigidity and increase the fracture resistance of non-vital teeth by rein-forcing unsupported
      tissues. Advanced adhesive systems with improved physical properties are more aesthetic and
      support remaining tooth structures better than amalgam. In order to reduce polymerization
      shrinkage stresses, flowable resins with low elastic modulus have been suggested as a
      stress-absorbing layer under composite restorations. On the other hand, the use of flowable
      resin does not increase fracture resistance, and this layer results in contraction stresses.

      Rational:

      In fact, the primary aims of "biomimetic dentistry" are to be as minimally invasive as
      possible, and to substitute the missing hard dental tissues with restorative materials
      closely resembling the natural tissues regarding their mechanical features and properties.

      Leno weaved Ultra-high-molecular-weight polyethylene (LWUHMWPE) fibers are plasma treated
      fibers. LWUHMWPE fiber reinforcement Ribbond systems (Ribbond THM, Ribbond Inc, Seattle, WA,
      USA) have been introduced in the attempt to increase composite resin toughness, thus
      increasing both durability and damage tolerance. These bondable reinforcement fibers can be
      closely adapted to the residual tooth structure without requiring additional preparation. The
      high modulus of elasticity and low flexural modulus of polyethylene fiber have a modifying
      effect on the interfacial stresses developed along the cavity walls.

      According to a systematic review published in 2021 that was done to evaluate various in vitro
      studies, it was confirmed that the effect of the Ultra-high-molecular weight polyethylene
      fibers is increasing the fracture resistance and making more favorable fractures in
      endodontically treated teeth. However, there is no enough clinical data regarding this point,
      so this proposal is introduced.
    

Intervention name(s): X-tra base & GrandioSO reinforced by Ribbond
Intervention type(s): Other
Intervention description(s): The missing peripheral tooth structure will be built up via 2-mm wedge-shaped a universal hybrid resin composite, GrandioSO . Then the polyethylene fibers will be wetted with an unfilled resin first . After removing the excess resin, fibers will be covered with a very thin layer of flowable composite X-tra base . After that, fibers will be bonded immediately against the peripheral missing walls and cured for 20 seconds. Then a bulk-fill flowable resin composite lining X-tra base will be applied in approximately 4 mm thick in bulk increments as needed to fill the cavity 2 mm short of the occlusal cavosurface and each increment will be light cured for 20 s. The remaining occlusal part of the cavity will be restored with a universal hybrid resin composite, GrandioSO . The shade of the composite will be selected according to the teeth to be restored. All cavities will be restored with open-sandwich technique (Deliperi, et al. 2017).
Other intervention name(s): Bulk Fill resin composite restorations (X-tra base & GrandioSO, Voco, Cuxhaven, Germany) reinforced by ultra high molecular weight polyethylene. (Ribbond THM, Ribbond Inc, Seattle, WA, USA)
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Double (Participant, Outcomes Assessor)
Primary purpose: Treatment
Keywords: Ribbond; Reinforced Composite; polyethylene Fibers