Effects of glass fibers reinforced and non-reinforced composite resin on fracture behavior of severely destructed primary incisors and restored with post and core system.

Objective: To evaluate fracture resistance and failure type of coronally rehabilitated primary incisors with EverX Flow or Grandio Core post and core with or without fiber post. Materials and Methods: Forty-eight extracted maxillary primary incisors were root canal treated and obturated with Metapex. The coronal 4-mm of Metapex was removed to create 3-mm intracanal post space. Next, coronal enamel and radicular dentin surfaces were acid-etched, and a bonding agent was applied and light-cured. Based on intracanal post and 2-mm height core buildup materials, specimens were divided equally (n = 12) into 4 groups as follow; Group I (EverX Flow), Group II (Grandio Core), Group III (Fiber post, and EverX Flow), and Group IV(Fiber post and Grandio Core). The coronal restorations were finalized to 4-mm height using G-aenial Anterior composite and specimens were tested for fracture resistance. Force required to induce fracture was recorded and failure type was examined. Results: Fracture resistance of Fiber post and EverX Flow group was statistically significant high than other tested groups. However, fracture resistance of EverX Flow group showed non-statistically significant difference from that of Fiber post and Grandio Core group. Regarding failure type, no specimen presented root fracture, and all failures were favorable and repairable. Conclusion: EverX flow post and core with or without fiber post enhanced fracture resistance of restored primary incisors compared to Grandio Core alone. Clinical relevance: EverX flow post and core system with or without fiber post could be a promising restorative option for severely destructed primary incisors.

Effect of adhesive resin application on the progression of cavitated and non-cavitated incipient carious lesions.

PURPOSE: To evaluate the penetration of two different adhesive resin systems into cavitated and non-cavitated artificial carious lesions and the behavior of treated carious lesions under further acid attack. METHODS: Artificial caries-like lesions were created on the proximal surface of 100 human primary molars by a demineralizing gel. The teeth were assigned to three groups according to the adhesive resin used. Group 1 (G1) was for Single Bond adhesive resin, Group 2 (G2) for Xeno V adhesive resin, and Group 3 (G3) was without any adhesive application. Each group was randomly and equally subdivided into subgroups a and b. In subgroup a, the teeth were kept with intact artificial caries-like lesion surfaces while in the subgroup b, a minute cavity was made at the center of artificial caries-like lesions using a sharp explorer. Each tooth was sectioned occluso-cervically into two halves through the center of the lesion; the sectioned surface was polished and examined under a reflected light microscope for estimating the depth of the carious lesion or penetration of the adhesive resin. All tooth halves were coated at the sectioned surface with two layers of acid resistant nail varnish and returned again to the demineralizing solution to assess the progression or arrest of the carious lesion after the second acid attack. RESULTS: The penetration depth of adhesive resins did not differ significantly between subgroups (P>0.05). After the second acid attack, the infiltrated carious lesions showed no lesion progression while the non-infiltrated lesions showed advanced caries progression.