Analysis of the Prognostic Factors That Influence the Outcome of Periapical Surgery, including Biomimetic Membranes for Tissue Regeneration: A Review.

The objective of this study was to analyze the prognostic factors that influence the outcome of periapical surgery. A systematic search of the literature was carried out using PubMed and Scopus databases between January 2000 and December 2023 with no language limitations. The PICO question of the present systematic review was: What prognostic factors may influence the outcome of periapical surgery? The most relevant randomized controlled clinical trials (RCTs), prospective clinical trials, retrospective studies, and meta-analyses (n = 44) were selected from 134 articles. The reviewed literature evidenced that bone-lesion healing could significantly be improved by the absence of deep periodontal pockets (>4 mm), localization in anterior teeth, the absence of pain and/or preoperative symptoms, a size of bone lesion < 5 mm, the use of ultrasound, the correct placement of retrograde filling material, and the use of different biomimetic membranes for guided tissue regeneration (GTR). Some preoperative and intraoperative factors could significantly improve the prognosis of periapical surgery. However, these results were not conclusive, and further high-quality research is required.

Intra- and inter-operator concordance of the resonance frequency analysis. A cross-sectional and prospective clinical study.

OBJECTIVE: Resonance frequency analysis (RFA) provides an evaluation of implant stability over time. This analysis is a non-invasive, precise, and objective method. Several studies compare the RFA system with other devices. However, few investigations analyze repeatability and reproducibility between different operators. The aim of this study was to evaluate the intra- and inter-operator concordance of the Osstell® ISQ. MATERIAL AND METHODS: RFA measurements were performed with Osstell® ISQ in a total of 37 implants placed in 21 patients. At the time of implant placement, 6 measurements per implant were taken by three different experienced operators. Three measurements were carried out consecutively and three by removing and placing the SmartPeg-Osstell® to assess intra-operator and inter-operator agreement. RESULTS: Intra-operator concordance according to the intraclass correlation coefficient (ICC) showed high concordance. The ICC values were higher than 0.9 (p < 0.0001) for consecutive measures and alternative measures, being almost perfect of Landis & Koch classification. For inter-operator concordance The ICC was 0.709 (p < 0.0001) and 0.670 (p < 0.0001) for consecutive and alternative measures, respectively, both estimates being in the substantial category. In torque and ISQ values, no statistically significant differences were observed when operators and measurements were compared. CONCLUSIONS: Osstell® ISQ system was stable both in intra-operator and inter-operator measurements. This device has excellent repeatability and reproducibility, demonstrating reliability to measure the stability of dental implants. CLINICAL RELEVANCE: Resonance frequency analysis (RFA) is a non-invasive, objective, and reliable diagnostic method to determine the ideal moment to load the implant, as well as to predict possible failures.

A Systematic Review and Meta-Analysis of Systemic Antibiotic Therapy in the Treatment of Peri-Implantitis.

Research has been conducted into the advantages of the systemic administration of antibiotics. The aim of this systematic review and meta-analysis was to assess the efficacy of systemic antibiotic administration in the treatment of peri-implantitis in terms of bleeding on probing (BoP) and probing pocket depth (PPD). Literature searches were performed across PubMed, EMBASE, and Cochrane Central Register of Controlled Trials (CENTRAL) to identify randomized controlled trials and observational clinical studies. After peri-implantitis treatment, PPD was reduced by 0.1 mm (p = 0.58; IC 95% [-0.24, 0.47]), indicating a non-significant effect of antibiotic administration on PPD. The BoP odds ratio value was 1.15 (p = 0.5; IC 95% [0.75, 1.75]), indicating that the likelihood of bleeding is almost similar between the test and control groups. Secondary outcomes were found, such as reduced clinical attachment level, lower suppuration and recession, less bone loss, and a reduction in total bacterial counts. In the treatment of peri-implantitis, the systemic antibiotic application reduces neither PPD nor BoP. Therefore, the systemic administration of antibiotics, in the case of peri-implantitis, should be rethought in light of the present results, contributing to address the problem of increasing antibiotic resistance.

Treating Gingival Recessions Using Coronally Advanced Flap or Tunnel Techniques with Autografts or Polymeric Substitutes: A Systematic Review and Meta-Analysis.

Gingival recessions are a prevalent oral mucosa alteration. To solve this pathology, palatal mucosa or polymeric soft tissue substitutes are used when performing coronal advanced flap (CAF) or tunnel (TUN) surgical techniques. To evaluate which is the most successful approach, a literature review and meta-analysis were conducted. For the electronic search the National Library of Medicine, the Cochrane Oral Health Group Trials Register, EMBASE and WOS were used. Pooled data for the percentage of root coverage was collected and weighted means were calculated. Heterogeneity was determined using the Higgins (I2) statistic and a random-effects model was applied. Thirteen studies were included in the systematic review (12 randomized and 1 controlled clinical trials) in which both techniques (394 patients) were compared with a follow-up of 4 to 12 months. Galbraith and Baujat plots were used to control for the presence of potential outliers. After performing the meta-analysis (11 studies), the mean root coverage was similar when using the TUN or CAF techniques (p = 0.49). The only differences between the two were found for single recessions, where CAF offered a higher percentage of root coverage (mean difference = 4.98%; p = 0.006). There were no differences when applying an autograft or a polymeric substitute with either of the two tested surgical techniques (p = 0.445).

Melatonin-doped polymeric nanoparticles induce high crystalline apatite formation in root dentin.

OBJECTIVE: To investigate the effect of novel polymeric nanoparticles (NPs) doped with melatonin (ML) on nano-hardness, crystallinity and ultrastructure of the formed hydroxyapatite after endodontic treatment. METHODS: Undoped-NPs and ML-doped NPs (ML-NPs) were tested at radicular dentin, after 24 h and 6 m. A control group without NPs was included. Radicular cervical and apical dentin surfaces were studied by nano-hardness measurements, X-ray diffraction and transmission electron microscopy. Mean and standard deviation were analyzed by ANOVA and Student-Newman-Keuls multiple comparisons (p < 0.05). RESULTS: Cervical dentin treated with undoped NPs maintained its nano-hardness values after 6 m of storage being [24 h: 0.29 (0.01); 6 m: 0.30 (0.02) GPa], but it decreased at apical dentin [24 h: 0.36 (0.01); 6 m: 0.28 (0.02) GPa]. When ML-NPs were used, nano-hardness was similar over time [24h: 0.31 (0.02); 6 m: 0.28 (0.03) GPa], at apical dentin. Root dentin treated with ML-NPs produced, in general, high crystallinity of new minerals and thicker crystals than those produced in the rest of the groups. After 6 m, crystals became organized in randomly oriented polyhedral, square polygonal block-like apatite or drop-like apatite polycrystalline lattices when ML-NPs were used. Undoped NPs generated poor crystallinity, with preferred orientation of small crystallite and increased microstrain. SIGNIFICANCE: New polycrystalline formations encountered in dentin treated with ML-NPs may produce structural dentin stability and high mechanical performance at the root. The decrease of mechanical properties over time in dentin treated without NPs indicates scarce remineralization potential, dentin demineralization and further potential degradation. The amorphous stage may provide high hydroxyapatite solubility and remineralizing activity.

Effect of Propolis Paste and Mouthwash Formulation on Healing after Teeth Extraction in Periodontal Disease.

This study investigated the antimicrobial effects of a mouthwash containing propolis and the effect of a propolis paste formulation on dental healing after teeth extraction in patients with periodontal disease. In the mouthwash experience, the population comprised 40 patients, which were divided as follows: the control mouthwash, 0.2% chlorhexidine (v/v) mouthwash, 2% (w/v) propolis mouthwash, and propolis + chlorhexidine mouthwash. The study of the propolis paste comprised a population of 60 patients with periodontal disease, and a total of 120 symmetric tooth extractions were performed. Propolis showed antimicrobial activity by itself, and especially with the chlorhexidine association. Three days after surgery in the teeth treated with control paste, only 13.4% had completely healed; however, with propolis paste, in 90% of the periodontal sockets, healing was complete. In addition, a reduction in Streptococci mutans and Lactobacilli cfu was observed with propolis, and especially with the association of chlorhexidine + propolis. Propolis mouthwash reduced bacterial proliferation, especially in association with chlorhexidine. Propolis paste is a viable alternative for socket healing after dental extraction. The knowledge gained from these findings will provide a foundation for similar propolis therapies in order to improve the healing process after dental surgery.

Zn-Containing Membranes for Guided Bone Regeneration in Dentistry.

Barrier membranes are employed in guided bone regeneration (GBR) to facilitate bone in-growth. A bioactive and biomimetic Zn-doped membrane with the ability to participate in bone healing and regeneration is necessary. The aim of the present study is to state the effect of doping the membranes for GBR with zinc compounds in the improvement of bone regeneration. A literature search was conducted using electronic databases, such as PubMed, MEDLINE, DIMDI, Embase, Scopus and Web of Science. A narrative exploratory review was undertaken, focusing on the antibacterial effects, physicochemical and biological properties of Zn-loaded membranes. Bioactivity, bone formation and cytotoxicity were analyzed. Microstructure and mechanical properties of these membranes were also determined. Zn-doped membranes have inhibited in vivo and in vitro bacterial colonization. Zn-alloy and Zn-doped membranes attained good biocompatibility and were found to be non-toxic to cells. The Zn-doped matrices showed feasible mechanical properties, such as flexibility, strength, complex modulus and tan delta. Zn incorporation in polymeric membranes provided the highest regenerative efficiency for bone healing in experimental animals, potentiating osteogenesis, angiogenesis, biological activity and a balanced remodeling. Zn-loaded membranes doped with SiO2 nanoparticles have performed as bioactive modulators provoking an M2 macrophage increase and are a potential biomaterial for promoting bone repair. Zn-doped membranes have promoted pro-healing phenotypes.

Composición corporal, metabolismo mineral y función endocrina del tejido adiposo: influencia de un suplemento nutricional de propóleo / Body composition, mineral metabolism, and endocrine function of adipose tissue: influence of a nutritional supplement of propolis

Introducción: el propóleo y sus componentes influyen en el metabolismo lipídico; sin embargo, se desconoce su efecto sobre la composición corporal y el metabolismo mineral. Objetivos: determinar el efecto de la suplementación de la dieta con propóleo natural sobre la composición corporal, el metabolismo basal y mineral, y la función endocrina del tejido adiposo. Material y métodos: veinte ratas albinas Wistar macho (8 semanas) se dividieron en dos grupos de 10 animales cada uno. Las ratas fueron alimentadas con dos tipos diferentes de dietas durante 90 días: una dieta estándar para el grupo de control (grupo C) y la misma dieta estándar + un 2 % de propóleo (grupo P). Se determinaron las hormonas tiroideas, la grelina, la leptina, la adiponectina y la insulina, los ácidos grasos no esterificados (AGNE) en el plasma, la composición corporal (masa magra, masa grasa y agua corporal) y el depósito de minerales en órganos diana (bazo, cerebro, corazón, pulmones, testículos, riñones y fémur). Resultados: los niveles plasmáticos de hormona estimulante del tiroides (TSH), triyodotironina (T3) y tiroxina (T4) no mostraron diferencias tras la ingesta del suplemento de propóleo, mientras que los de grelina y adiponectina disminuyeron (p < 0,01 y p < 0,05, respectivamente) y los de insulina (p < 0,01), leptina (p < 0,05) y AGNE (p < 0,05) aumentaron cuando la dieta se suplementó con propóleo al 2 %. Se redujeron el peso y la grasa corporal (p < 0,05), incrementándose la masa magra. Por último, el suplemento de propóleo mejoró el depósito de calcio en el bazo, los pulmones, los testículos y el fémur (p < 0,05). (AU)

Introduction: propolis and its components influence lipid metabolism; however, its effect on body composition and mineral metabolism remains unknown. Objectives: to determine the effect of natural propolis supplementation on body composition, mineral metabolism, and the endocrine function of adipose tissue. Material and methods: twenty albino male Wistar rats (8 weeks old) were divided into two groups of 10 animals each. The rats were fed two different types of diet for 90 days: a standard diet for the control group (group C) and the same standard diet + 2 % propolis (group P). Thyroid hormones, ghrelin, leptin, adiponectin and insulin, non-esterified fatty acids (NEFA) in plasma, body composition (lean mass, fat mass and body water), and mineral deposition in target organs (spleen, brain, heart, lungs, testicles, kidneys and femur) were assessed. Results: thyroid stimulating hormone (TSH), triiodothyronine (T3) and thyroxine (T4) did not show any differences after supplementation with propolis, while ghrelin and adiponectin decreased (p < 0.01 and p < 0.05, respectively) and insulin (p < 0.01), leptin (p < 0.05) and NEFA (p < 0.05) increased when 2 % propolis was supplied, while weight and body fat were reduced (p < 0.05) and lean mass increased. Lastly, the propolis supplement improves calcium deposition in the spleen, lungs, testes, and femur (p < 0.05). (AU)

[Body composition, mineral metabolism, and endocrine function of adipose tissue: influence of a nutritional supplement of propolis]. / Composición corporal, metabolismo mineral y función endocrina del tejido adiposo: influencia de un suplemento nutricional de propóleo.

INTRODUCTION: Introduction: propolis and its components influence lipid metabolism; however, its effect on body composition and mineral metabolism remains unknown. Objectives: to determine the effect of natural propolis supplementation on body composition, mineral metabolism, and the endocrine function of adipose tissue. Material and methods: twenty albino male Wistar rats (8 weeks old) were divided into two groups of 10 animals each. The rats were fed two different types of diet for 90 days: a standard diet for the control group (group C) and the same standard diet + 2 % propolis (group P). Thyroid hormones, ghrelin, leptin, adiponectin and insulin, non-esterified fatty acids (NEFA) in plasma, body composition (lean mass, fat mass and body water), and mineral deposition in target organs (spleen, brain, heart, lungs, testicles, kidneys and femur) were assessed. Results: thyroid stimulating hormone (TSH), triiodothyronine (T3) and thyroxine (T4) did not show any differences after supplementation with propolis, while ghrelin and adiponectin decreased (p < 0.01 and p < 0.05, respectively) and insulin (p < 0.01), leptin (p < 0.05) and NEFA (p < 0.05) increased when 2 % propolis was supplied, while weight and body fat were reduced (p < 0.05) and lean mass increased. Lastly, the propolis supplement improves calcium deposition in the spleen, lungs, testes, and femur (p < 0.05). Conclusion: propolis supplementation of the diet (2 %) causes a decrease in the secretion of ghrelin and adiponectin, increasing the release of non-esterified fatty acids and the rate of insulin secretion. In addition, propolis supplementation induces an improvement in calcium deposition in target organs without affecting the rest of minerals, which improves body composition by inducing a reduction in weight and visceral adipose tissue, and improvement in lean mass.

INTRODUCCIÓN: Introducción: el propóleo y sus componentes influyen en el metabolismo lipídico; sin embargo, se desconoce su efecto sobre la composición corporal y el metabolismo mineral. Objetivos: determinar el efecto de la suplementación de la dieta con propóleo natural sobre la composición corporal, el metabolismo basal y mineral, y la función endocrina del tejido adiposo. Material y métodos: veinte ratas albinas Wistar macho (8 semanas) se dividieron en dos grupos de 10 animales cada uno. Las ratas fueron alimentadas con dos tipos diferentes de dietas durante 90 días: una dieta estándar para el grupo de control (grupo C) y la misma dieta estándar + un 2 % de propóleo (grupo P). Se determinaron las hormonas tiroideas, la grelina, la leptina, la adiponectina y la insulina, los ácidos grasos no esterificados (AGNE) en el plasma, la composición corporal (masa magra, masa grasa y agua corporal) y el depósito de minerales en órganos diana (bazo, cerebro, corazón, pulmones, testículos, riñones y fémur). Resultados: los niveles plasmáticos de hormona estimulante del tiroides (TSH), triyodotironina (T3) y tiroxina (T4) no mostraron diferencias tras la ingesta del suplemento de propóleo, mientras que los de grelina y adiponectina disminuyeron (p < 0,01 y p < 0,05, respectivamente) y los de insulina (p < 0,01), leptina (p < 0,05) y AGNE (p < 0,05) aumentaron cuando la dieta se suplementó con propóleo al 2 %. Se redujeron el peso y la grasa corporal (p < 0,05), incrementándose la masa magra. Por último, el suplemento de propóleo mejoró el depósito de calcio en el bazo, los pulmones, los testículos y el fémur (p < 0,05). Conclusión: el suplemento de propóleo al 2 % de la dieta produjo una disminución de la secreción de grelina y adiponectina, incrementando la concentración de AGNE y aumentando la tasa de secreción de insulina. Además, el suplemento de propóleo indujo una mejora del depósito de calcio en los órganos diana sin afectar al resto de minerales, lo que en conjunto mejora la composición corporal al inducir una reducción del peso y del tejido adiposo visceral, mejorando la masa magra.

[Positive effect of a propolis supplement on lipid profile, glycemia, and hepatic antioxidant status in an experimental animal model]. / Efecto positivo de un suplemento de propóleo sobre el perfil lipídico, la glucemia y el estado antioxidante hepático en un modelo animal experimental.

INTRODUCTION: Introduction: the use of natural nutritional supplements can be used as a coadjuvant therapy since they have several phytochemicals with potential antioxidant effects that could influence lipid and glycemic metabolism. Objectives: to determine the effect of natural propolis supplementation on lipid metabolism and liver antioxidant activity. Material and methods: 20 male Wistar albino rats (8 weeks) were divided into two groups of 10 animals each. Subsequently, they were fed two different types of diet for 90 days: a standard diet for the control group (diet C) and a standard diet + 2 % propolis (diet P). Hematological and biochemical parameters were assessed. The livers were extracted and washed with saline solution, and the cytosolic fractions were prepared fresh for additional analysis of antioxidant enzymes catalase, superoxide dismutase, glutathione peroxidase, and glutathione reductase. Results: after consuming the diet supplemented with propolis, we found a reduction in glucose (p < 0,01), total cholesterol (p < 0,001), GOT (p < 0,05) and GPT (p < 0,01), whereas the propolis supplement induced an increase in the hepatic activity of SOD (p < 0,001), CAT (p < 0,01) and GR (p < 0,05). Conclusion: the present study reveals that a dietary propolis supplement (2 %) can improve the lipid and glycemic profiles, also increasing antioxidant enzimes and reducing the release of liver transaminases.

INTRODUCCIÓN: Introducción: el uso de suplementos nutricionales naturales puede ser una terapia complementaria ya que tienen fitoquímicos con posibles efectos antioxidantes que pueden mejorar la regulación del metabolismo lipídico y glucémico. Objetivos: determinar el efecto de la suplementación con propóleo natural sobre el metabolismo lipídico y la actividad antioxidante hepática. Material y métodos: 20 ratas albinas Wistar macho (8 semanas) se dividieron en dos grupos de 10 animales cada uno y se sometieron a un período de 90 días en el que se alimentaron con dos tipos diferentes de dietas: estándar para el grupo de control (dieta C) y dieta estándar + 2 % de propóleo (dieta P). Se determinaron los parámetros hematológicos y bioquímicos. Se extrajeron los hígados, se lavaron con solución salina y las fracciones citosólicas se prepararon frescas para análisis adicionales de las enzimas antioxidantes catalasa, superóxido-dismutasa, glutatión-peroxidasa y glutatión-reductasa. Resultados: tras el consumo de la dieta con suplemento de propóleo, encontramos una reducción de la glucosa (p < 0,01), el colesterol total (p < 0,001), la GOT (p < 0,05) y la GPT (p < 0,01), mientras que dicha dieta indujo un incremento en la actividad hepática de SOD (p < 0,001), CAT (p < 0,01) y GR (p < 0,05). Conclusión: el presente estudio revela que el suplemento nutricional de propóleo al 2 % puede mejorar significativamente el perfil lipídic, el glucémico y las enzimas antioxidantes, y reducir la liberación de GOT y GPT hepáticas.

Efecto positivo de un suplemento de propóleo sobre el perfil lipídico, la glucemia y el estado antioxidante hepático en un modelo animal experimental / Positive effect of a propolis supplement on lipid profile, glycemia, and hepatic antioxidant status in an experimental animal model

INTRODUCCIÓN: el uso de suplementos nutricionales naturales puede ser una terapia complementaria ya que tienen fitoquímicos con posibles efectos antioxidantes que pueden mejorar la regulación del metabolismo lipídico y glucémico. OBJETIVOS: determinar el efecto de la suplementación con propóleo natural sobre el metabolismo lipídico y la actividad antioxidante hepática. MATERIAL Y MÉTODOS: 20 ratas albinas Wistar macho (8 semanas) se dividieron en dos grupos de 10 animales cada uno y se sometieron a un período de 90 días en el que se alimentaron con dos tipos diferentes de dietas: estándar para el grupo de control (dieta C) y dieta estándar + 2 % de propóleo (dieta P). Se determinaron los parámetros hematológicos y bioquímicos. Se extrajeron los hígados, se lavaron con solución salina y las fracciones citosólicas se prepararon frescas para análisis adicionales de las enzimas antioxidantes catalasa, superóxido-dismutasa, glutatión-peroxidasa y glutatión-reductasa. RESULTADOS: tras el consumo de la dieta con suplemento de propóleo, encontramos una reducción de la glucosa (p < 0,01), el colesterol total (p < 0,001), la GOT (p < 0,05) y la GPT (p < 0,01), mientras que dicha dieta indujo un incremento en la actividad hepática de SOD (p < 0,001), CAT (p < 0,01) y GR (p < 0,05). CONCLUSIÓN: el presente estudio revela que el suplemento nutricional de propóleo al 2 % puede mejorar significativamente el perfil lipídic, el glucémico y las enzimas antioxidantes, y reducir la liberación de GOT y GPT hepáticas

INTRODUCTION: the use of natural nutritional supplements can be used as a coadjuvant therapy since they have several phytochemicals with potential antioxidant effects that could influence lipid and glycemic metabolism. OBJECTIVES: to determine the effect of natural propolis supplementation on lipid metabolism and liver antioxidant activity. MATERIAL AND METHODS: 20 male Wistar albino rats (8 weeks) were divided into two groups of 10 animals each. Subsequently, they were fed two different types of diet for 90 days: a standard diet for the control group (diet C) and a standard diet + 2 % propolis (diet P). Hematological and biochemical parameters were assessed. The livers were extracted and washed with saline solution, and the cytosolic fractions were prepared fresh for additional analysis of antioxidant enzymes catalase, superoxide dismutase, glutathione peroxidase, and glutathione reductase. RESULTS: after consuming the diet supplemented with propolis, we found a reduction in glucose (p < 0,01), total cholesterol (p < 0,001), GOT (p < 0,05) and GPT (p < 0,01), whereas the propolis supplement induced an increase in the hepatic activity of SOD (p < 0,001), CAT (p < 0,01) and GR (p < 0,05). CONCLUSION: the present study reveals that a dietary propolis supplement (2 %) can improve the lipid and glycemic profiles, also increasing antioxidant enzimes and reducing the release of liver transaminases

Polymeric nanoparticles for endodontic therapy.

The effectiveness of novel polymeric nanoparticles (NPs) application in reducing dentin permeability and facilitating dentin remineralization after endodontic treatment was evaluated. The effect of undoped NPs, zinc, calcium and doxycycline-doped NPs (Zn-NPs, Ca-NPs and D-NPs, respectively) was tested in radicular dentin. A control group without NPs was included. Radicular dentin was assessed for fluid filtration. Dentin remineralization was analyzed by scanning and transmission electron microscopy, energy-dispersive analysis, AFM, Young's modulus (Ei), Nano DMA, Raman, and X-Ray Diffraction analysis. Ca-NPs and Zn-NPs treated dentin exhibited the lowest microleakage with hermetically sealed dentinal tubules and a zinc-based salt generation onto dentin. Zn-NPs favored crystallinity and promoted the highest Ei and functional remineralization at the apical dentin, generating differences between the values of complex modulus among groups. Ca-NPs produced closure of tubules and porosities at the expense of a relative mineral amorphization, without creating zones of stress concentration. The highest sealing efficacy was obtained in Zn-NPs-treated samples, along with the highest values of Young's modulus and dentin mineralization. These high values of Ei were obtained by closing voids, cracks, pores and tubules, and by strengthening the root dentin. When using undoped NPs or Ca-NPs, deposition of minerals occurred, but radicular dentin was not mechanically reinforced. Therefore, application of Zn-NPs in endodontically treated teeth previous to the canal filling is encouraged.

The mineralizing effect of zinc oxide-modified hydroxyapatite-based sealer on radicular dentin.

OBJECTIVE: The aim of this study was to evaluate the remineralization ability of three endodontic sealer materials at different root dentin regions. MATERIAL AND METHODS: Cervical, medial, and apical root dentin surfaces were treated with two experimental hydroxyapatite-based cements, containing sodium hydroxide (calcypatite) or zinc oxide (oxipatite); an epoxy resin-based canal sealer, AH Plus; and gutta-percha. Remineralization, at the inner and outer zones of dentin disk surfaces, was studied by nanohardness (Hi) and Raman analysis. Nanoroughness and collagen fibrils width measurements were performed. Numerical data, at 24 h or 12 m, were analyzed by ANOVA and Student-Newman-Keuls (p < 0.05). RESULTS: At the outer and inner zones of the cervical dentin treated with oxipatite, the highest Hi after 12 m of immersion was achieved. The same group showed the highest intensity of phosphate peak, markers for calcification and crystallinity. Nanoroughness was lower and fibril diameter was higher at the inner zone of the dentin treated with oxipatite. Dentin mineralization occurred in every region of the root dentin treated with oxipatite and calcypatite, especially at the inner zone of the dentin after 12 m. CONCLUSIONS: Oxipatite reinforced the inner root zone at any third of the radicular dentin, by increasing both nanohardness and remineralization. When using calcypatite, the highest nanohardness was found at the apical third of the inner root dentin, but the lowest mechanical performance was obtained at the cervical and the medial thirds of the roots. Therefore, application of oxipatite as sealing cement of root canals is recommended. CLINICAL RELEVANCE: Oxipatite, when used as an endodontic sealing material, strengthens radicular dentin.

Hydroxyapatite-based cements induce different apatite formation in radicular dentin.

OBJECTIVE: To investigate crystallinity and ultrastructure of the formed hydroxyapatite at radicular cervical and apical dentin after being treated with three different canal sealers. METHODS: Cervical and apical root dentin surfaces were treated with two experimental hydroxyapatite-based sealers, containing sodium hydroxide (calcypatite) or zinc oxide (oxipatite) and an epoxy resin-based canal sealer (AH Plus); gutta-percha without sealer was included as control. Dentin surfaces were studied by X-ray diffraction and transmission electron microscopy through selected area diffraction and bright-field imaging after 24h and 12m of storage. RESULTS: Root cervical dentin treated with calcypatite and oxipatite produced poor crystallinity of new minerals, wide amorphous phase and non-stoichiometry. Reflections at the 002 plane and the corresponding diffraction rings attained lower values in the Scherrer equation and the Scherrer-Wilson equation in samples treated with both HAp-based sealers than in specimens without sealer or with AH Plus. At root cervical dentin treated with calcypatite, shorter and wider crystallite size formations and lower crystals grain size were found, if compared to those encountered at oxipatite treated dentin. Oxipatite attained improved crystallographic atomic order and less structural variation in both distances and angles. Apical dentin treated with oxipatite attained preferred grain orientation with polycrystalline lattices. SIGNIFICANCE: The immature crystallites formed in dentin treated with calcypatite and oxipatite will account for high hydroxyapatite solubility and remineralizing activity. New polycrystalline formations encountered in apical dentin treated with oxipatite may also produce high mechanical performance.

A zinc oxide-modified hydroxyapatite-based cement favored sealing ability in endodontically treated teeth.

OBJECTIVES: To evaluate the effectiveness of different endodontic canal sealers for dentin permeability reduction and to determine the viscoelastic performance of root dentin after their application. METHODS: Cervical, medial and apical root dentin surfaces were treated with two experimental hydroxyapatite-based cements, containing sodium hydroxide (calcypatite) or zinc oxide (oxipatite); an epoxy resin- based canal sealer, AH Plus; and gutta-percha. Root dentin was evaluated for fluid filtration. Field emission scanning electron microscopy, energy dispersive analysis, AFM, Young's modulus and Nano-DMA analysis were also performed, at the inner and outer zones of dentin. RESULTS: Dentin treated with oxipatite showed the lowest microleakage among groups with hermetically sealed tubules and zinc-based salt formations. Samples treated with oxipatite showed the highest Ei at the cervical dentin third among groups, at 6 m of storage. Oxipatite promoted the highest complex modulus and tan delta values at the inner zone of both cervical and medial root dentin. Calcypatite favored the lowest tan delta outcomes at the inner zone of apical dentin at 6 m. CONCLUSIONS: Specimens treated with oxipatite showed the highest sealing ability, based on the highest Young's modulus and dentin mineralization, achieved by closing dentinal tubules, voids and pores that reinforced the inner zone of root dentin. The homogeneity of viscoelastic properties among the different root dentin thirds favored the energy dissipation without creating zones of stress concentration and micro-cracking which would have challenge micropermeability. Thereby, among the tested materials oxipatite is proposed as canal filling material and sealer in endodontics. CLINICAL SIGNIFICANCE: Oxipatite could be considered a good candidate for root canal filling material and sealer due to its improved long-term sealing ability and to the advanced remineralization, and so to the enhanced energy dissipation achieved at the inner zone of the radicular dentin.

Effectiveness of 1% versus 0.2% chlorhexidine gels in reducing alveolar osteitis from mandibular third molar surgery: A randomized, double-blind clinical trial

Purpose: Alveolar osteitis (AO) is the most common postoperative complication of dental extractions. The purpose of this study was to compare the effectiveness of 1% versus 0.2% chlorhexidine (CHX) gel in reducing postoperative AO after surgical extraction of mandibular third molars, and assess the impact of treatment on the Oral HealthRelated Quality of Life (OHRQoL). Material and Methods: This clinical study was a randomized, double-blind clinical trial. Eighty eight patients underwent surgical extraction of one retained mandibular third molar with the intra-alveolar application of 0.2% CHX gel. Afterwards, they were assigned to one of two groups: 1% CHX gel (n=42) or 0.2% CHX gel (n=46). The patients applied the gel twice a day to the wound for one week. All patients were evaluated for AO. Results: In the 0.2% CHX gel group, 13% of AO incidence was found, while in the 1% CHX gel group, AO incidence was 7%, a difference that was not statistically significant. Variables such as sensation of pain and inflammation at baseline and during one week, as well as OHRQoL of the patients at 24 hours and 7 days post-extraction, gave no statistically significant differences. Conclusions: There are no significant differences in AO after surgical extraction of mandibular third molars, when comparing applying 1% CHX gel twice a day for 7 days with 0.2% CHX gel (AU)

Effectiveness of 1% versus 0.2% chlorhexidine gels in reducing alveolar osteitis from mandibular third molar surgery: a randomized, double-blind clinical trial.

PURPOSE: Alveolar osteitis (AO) is the most common postoperative complication of dental extractions. The purpose of this study was to compare the effectiveness of 1% versus 0.2% chlorhexidine (CHX) gel in reducing postoperative AO after surgical extraction of mandibular third molars, and assess the impact of treatment on the Oral HealthRelated Quality of Life (OHRQoL). MATERIAL AND METHODS: This clinical study was a randomized, double-blind clinical trial. Eighty eight patients underwent surgical extraction of one retained mandibular third molar with the intra-alveolar application of 0.2% CHX gel. Afterwards, they were assigned to one of two groups: 1% CHX gel (n=42) or 0.2% CHX gel (n=46). The patients applied the gel twice a day to the wound for one week. All patients were evaluated for AO. RESULTS: In the 0.2% CHX gel group, 13% of AO incidence was found, while in the 1% CHX gel group, AO incidence was 7%, a difference that was not statistically significant. Variables such as sensation of pain and inflammation at baseline and during one week, as well as OHRQoL of the patients at 24 hours and 7 days post-extraction, gave no statistically significant differences. CONCLUSIONS: There are no significant differences in AO after surgical extraction of mandibular third molars, when comparing applying 1% CHX gel twice a day for 7 days with 0.2% CHX gel.

Dental implant stability is influenced by implant diameter and localization and by the use of plasma rich in growth factors.

PURPOSE: The objective was to analyze the factors that influence the stability of dental implants at 12 weeks after implant placement as measured by resonance frequency analysis using the Osstell system. MATERIALS AND METHODS: This prospective clinical study was performed in 235 implants placed in 93 patients at the Oral Surgery and Implantology Clinic of the University of Granada. The gathered predictor variables were grouped into patient variables, implant variables, operative variables, and baseline implant stability quotient (ISQ). All variables were analyzed in a multivariate model to determine their influence on the ISQ score at 12 weeks after implant insertion (outcome variable). SUDAAN software was used for clustered sampling (multiple implants in patients). RESULTS: Two hundred thirty-five dental implants were placed in 47 men (50.5%) and 46 women (49.5%; total, 93 patients; mean age, 52.13 ± 11.23 years; range, 27 to 76 years). No association was found between the patient variables and the ISQ values at 12 weeks. Among implant variables, worse ISQ values at 12 weeks were observed for a narrow diameter (P < .001) and maxillary implants (P = .006). Among surgical technique variables, the use of plasma rich in growth factors (P = .011) showed the best ISQ values at 12 weeks. CONCLUSIONS: The diameter and localization of implants and the application of plasma rich in growth factors influenced the stability of implants measured at 12 weeks of wound healing. Accordingly, stability was less with a narrower implant diameter and maxillary localization and greater with implants humidified with plasma rich in growth factors.

Measurement of dental implant stability by resonance frequency analysis: A review of the literature

Dental implant treatment is an excellent option for prosthetic restoration that is associated with high successrates. Implant stability is essential for a good outcome. The clinical assessment of osseointegration is based onmechanical stability rather than histological criteria, considering primary stability (absence of mobility in bonebed after implant insertion) and secondary stability (bone formation and remodelling at implant-bone interface).The aim of this study was to review the literature on Resonance Frequency Analysis (RFA) as a methodfor measuring dental implant stability. An online search of various databases was conducted on experimentaland clinical research published between 1996 and 2008. The studies reviewed demonstrate the usefulness ofRFA as a non-invasive method to assess implant stability. Further research is required to determine whetherthis system is also capable of measuring the degree of dental implant osseointegration (AU)

Measurement of dental implant stability by resonance frequency analysis: a review of the literature.

Dental implant treatment is an excellent option for prosthetic restoration that is associated with high success rates. Implant stability is essential for a good outcome. The clinical assessment of osseointegration is based on mechanical stability rather than histological criteria, considering primary stability (absence of mobility in bone bed after implant insertion) and secondary stability (bone formation and remodelling at implant-bone interface). The aim of this study was to review the literature on Resonance Frequency Analysis (RFA) as a method for measuring dental implant stability. An online search of various databases was conducted on experimental and clinical research published between 1996 and 2008. The studies reviewed demonstrate the usefulness of RFA as a non-invasive method to assess implant stability. Further research is required to determine whether this system is also capable of measuring the degree of dental implant osseointegration.