Mechanical and Biocompatibility Properties of 3D-Printed Dental Resin Reinforced with Glass Silica and Zirconia Nanoparticles: In Vitro Study

This study aimed to assess the mechanical and biocompatibility properties of dental resin reinforced with different nanoparticle additives. Temporary crown specimens were 3D-printed and grouped based on nanoparticle type and amount, including zirconia and glass silica. Flexural strength testing evaluated the material's ability to withstand mechanical stress using a three-point bending test. Biocompatibility was tested using MTT and dead/live cell assays to assess effects on cell viability and tissue integration. Fractured specimens were analysed using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) for fracture surface examination and elemental composition determination. Results show that adding 5% glass fillers and 10-20% zirconia nanoparticles significantly improves the flexural strength and biocompatibility of the resin material. Specifically, the addition of 10%, 20% zirconia, and 5% glass silica by weight significantly increases the flexural strength of the 3D-printed resins. Biocompatibility testing reveals cell viabilities greater than 80% in all tested groups. Reinforced 3D-printed resin holds clinical potential for restorative dentistry, as zirconia and glass fillers have been shown to enhance mechanical and biocompatibility properties of dental resin, making it a promising option for dental restorations. The findings of this study may contribute to the development of more effective and durable dental materials.

Soft-tissues stabilization after immediate implant; platform switch with supraperiosteal augmentation

The architecture around an oral implant pushes the clinicians for an equalization of biological and physiological requirements. An esthetic implant-supported restoration needs plethora of knowledge and expertise. Surgeon skills can be of use for correct tridimensional position of implant in the extraction socket, shaped abutment contours, and anatomical final crown. An immediate implant placement for a fresh socket requires existing oral parameters judgment and evidence-based treatment plan. They are hard- and soft-tissue relationship, gingival biotype, and the tooth position. In this article, we describe a case of immediate implant placement, provisional crown, bovine bone contraction, soft-tissue collapse, and its management.

Management of the delicate phase of the temporary crown: an in vitro study

The fundamental moment of prosthetic rehabilitation is the "temporary". Although the meaning of the term diminishes its importance, the provisional has fundamental biological, aesthetic and functional functions. The oral cavity must maintain an adequate level of oral hygiene to carry out this delicate phase in the best possible way; a result achieved only with the collaboration of the prosthetic dentist with the hygienist and the patient, as if they were a biological system in motion. The different methods of hygiene are effective in maintaining a good level of oral health; but they could, if too aggressive, affect the prosthetic restoration. Our objective in vitro is to understand, after applying a known bacterial load, which hygiene method is the most effective in removing bacterial biofilm but at the same time is less aggressive towards resinous material.

Laboratory Study of Color Stability of Different Types of Materials for Temporary Constructions

INTRODUCTION

A temporary construction serves as a preliminary representation of the type and appearance of a future permanent one that is tailored to the patient's requirements. Like any prosthetic construction, it should meet the functional requirements, preserve or improve chewing and speech function. No matter how well maintained a prophylactic and functional prosthetic structure is, it will not be evaluated by the patient unless it retains and restores the existing shape, size and color of the natural teeth.

AIM

To determine instrumentally to what extent different colorants change the color of temporary constructions.

MATERIALS AND METHODS

Two materials for temporary restoration were tested - Protemp II and Protemp IV, of which a total of 100 test specimens, were fabricated. Under the equal storage conditions of room temperature and no direct access to sunlight, they were exposed to five 100-ml staining solutions: Coca-Cola, coffee (espresso), berry tea, orange juice and red wine in five separate containers. Measurements of color changes in the three areas of the tooth were performed using two spectrophotometric devices - Vita EasyShade and SpectroShade, at different time intervals - immediately before placement in the staining solution, at 1, 4, 7, and 14 days.

RESULTS

The results were analysed using the SPSS Statistical Processing Program (SPSS Inc., IBM SPSS Statistics) version 21.0. They were converted to a text file with the converter of the same program. In hypothesis testing, a standard value of p ≤ 0.05 was chosen for the level of significance that rejects the null hypothesis.

CONCLUSION

Based on this study, the strong colouring effect of coffee and red wine on these restorations was demonstrated. We can conclude that Protemp IV material showed better color stability compared to Protemp II.

Importance of interim restorations in the molar region

Interim restoration protects abutment teeth and periodontal tissues until prosthetic treatment ends with the fabrication of a definitive prosthesis, restores and maintains the functions and morphology of the stomatognathic system, and preserves the occlusal contact relationship. Temporary prostheses are used for a short time, to confirm the diagnosis and treatment plan. However, because interim restorations are used only briefly, their importance in ensuring the success of definitive prostheses is often overlooked. This review includes a comprehensive literature review of interim restoration of molars and summarizes the current clinical understanding and status of this functionally important area. Peer-reviewed publications were identified by searching PubMed in November 2018. An interim restoration, even when used briefly, can help dentists evaluate many aspects of the treatment plan and contribute to accurate prognosis of prosthetic treatment.