Acid-Base Resistant Zone in Teeth with the Direct Restoration Using Different Adhesive System Generations: A Systematic Review

ABSTRACT Objective: To find out what the acid-base resistant zone (ABRZ) is and the mechanism of its formation. Material and Methods: This systematic review was based on the search of laboratory studies in which selfetching adhesive systems were used. The electronic database PubMed was used for the search. The search began on August 2021 and ended on June 2022. We have analyzed the materials and methods of each research and entered them in the appropriate tables to give a clearer assessment of the obtained results. Results: This systematic review included 15 full-text articles published from 2011 to 2019. The ABRZ is formed on both dentine and enamel. On dentine, the ABRZ is formed only when using self-etching adhesive systems; on the enamel, on the contrary, the step of preliminary etch and rinse contributes to the formation of a thicker ABRZ. The functional monomer MDP and fluorine increase the thickness of the ABRZ and provide a hybrid layer /ABRZ boundary without defects and erosions. Conclusion: Self-etching adhesive systems ensure the creation of an ABRZ resistant to acid-base tests. This phenomenon can provide the resistance of tooth tissues to demineralization, and therefore increase their resistance to caries.

Immediate autogenous extracted tooth as a grafting material for fresh socket preservation: a systematic review / Diente autógeno de extracción inmediata como material de injerto para la conservación de alvéolos frescos: una revisión sistemática

Objectives: To evaluate the use of extracted autogenous teeth for socket preservation after tooth extraction. Material and Methods: Cochrane, Scopus, and PubMed databases search was conducted to identify human clinical studies reporting the clinical, radiographic and/or histological outcomes of socket preservation techniques with autogenous extracted tooth Only studies published in English language in the last 10 years were included in the study. Results: In total, 82 articles were identified. Five articles were included in the review. They included 58 teeth that were prepared as a graft for socket preservation. The grafts derived from autogenous teeth were presented in three forms: particles, blocks and powder. The mean bone loss ranged from 0.28 mm to 0.41mm in height and 0.15 mm in width. Conclusion: Immediate autogenous extracted tooth as a grafting material for fresh socket preservation is promising for future daily clinical practice. More clinical comparative studies are needed.

Objetivo: Evaluar el uso de dientes extraídos autógenos para la preservación del alveolo tras la extracción dental.Material y Métodos: Se realizó una búsqueda en las bases de datos Cochrane, Scopus y PubMed para identificar estudios clínicos en humanos que informaban los resultados clínicos, radiográficos y / o histológicos de las técnicas de preservación de alveolos con dientes extraídos autógenos. Solo se incluyeron estudios publicados en inglés en los últimos 10 años. Resultados: En total se identificaron 82 artículos. Se incluyeron cinco artículos en la revisión. Incluyeron 58 dientes que se prepararon como injerto para la preservación del alveolo. Los injertos derivados de dientes autógenos se presentaron en tres formas: partículas, bloques y polvo. La pérdida ósea media osciló entre 0,28 mm y 0,41 mm de altura y 0,15 mm de ancho. Conclusión: El diente autógeno extraído de forma inmediata utilizado como material de injerto para la conservación del alveolo fresco es prometedor para la práctica clínica diaria futura. Se necesitan más estudios clínicos comparativos.

The Substantiation of the Pre-Polymerization Heating Efficiency of the Dental Nanocomposite Material

Abstract Objective: To evaluate the effect of pre-polymerization heating of nanocomposite filling materials on their strength properties within one manufacture group. Material and Methods: Two nanocomposite filling materials Enamel Plus HRi Universal Dentin® and Universal Enamel® were used. The linear thermal expansion coefficient (LTEC), Young's modulus and penetration depth were determined during the tests. Changes in the structure of materials were evaluated using electron scanning microscopy. Results: Dentin nanocomposite samples after pre-heating and polymerization have higher LTEC after 30°C compared to dentine nanocomposite untreated samples with statistically significance started at 62°C (p<0.05) and higher temperature. Pre-polymerization heated samples had a statistically higher LTEC (p<0.05) at 57°С. It was revealed that Young's modulus of the dentin nanocomposite samples after thermal processing at 55°C was higher in total after the first heating cycle by 15% compared to the untreated dentin nanocomposite samples (p<0.05). The volume of total porosity after pre-heating decreased to 5-7% (p<0.05). Conclusion: The material that has undergone preliminary heat processing is significantly less deformed under load than the material that does not have thermal processing during the research was established and also has a denser structure.

Visualization features of canalis sinuosus with cone beam computed tomography

Introduction: One of the key stages of evaluating an edentulous ridge prior to dental implant placement is the analysis of neighboring anatomical structures such as canalis sinuosus (CS) with cone-beam computed tomography (CBCT). CBCT visualization has its own features, such as the change of slice thickness. The aim of the study was to analyze CS prevalence in relation to the slice thickness and CS diameter according to CBCT scans. Materials and Methods: In total, 100 CBCT scans of 39 males and 61 females in the age span of 46 to 81 years were retrospectively studied. Terminal alveolar part of CS was analyzed in Ez3D2009 (Vatech) software on panoramic and cross-sectional views with 0.5 mm, 1 mm, 3 mm, and 10 mm slice thicknesses. The prevalence was documented with regard to the diameter and slice thickness and was statistically compared in age and gender groups. Results: This CBCT study demonstrated 55.5% CS prevalence. There was no statistically significant difference in presence between age and gender groups regarding diameter as well as within different slice thickness. The study also showed the importance of the slice thickness choice for CS visualization: the best visualization was reached with 0.5 mm and 1 mm slice thicknesses. Visualization with 0.5 mm and 1 mm slice thicknesses was absolutely the same (55.5%). General CS prevalence with a 10 mm slice thickness (16.5%) was significantly lower (P < 0.05) than the prevalence with a 3 mm slice thickness (20.5%). The correlation between the slice thickness and a diameter more than 1.5 mm in size was not found. Conclusion: CBCT analysis showed that the highest CS prevalence was detected with the use of 0.5/1 mm slice thickness. As well, the higher CS diameter, the better is its visualization.