Effect of amoxicillin and clindamycin on the gene expression of markers involved in osteoblast physiology.

Background/purpose: Amoxicillin and clindamycin are the most effective decontaminants for intraoral bone grafts before their application in bone regeneration without cytotoxic effects on osteoblasts, but their effects on the gene expression of markers involved in osteoblast growth and differentiation remain unclear. The study objective was to determine the effects of amoxicillin and clindamycin on the gene expression of markers involved in osteoblast growth and differentiation. Materials and methods: Real-time polymerase chain reaction (RT-PCR) was performed to explore the effect of 150 µg/mL clindamycin or 400 µg/mL amoxicillin on the gene expression by primary human osteoblasts (HOBs) of runt-related transcription factor 2 (Runx-2), osterix (OSX), alkaline phosphatase (ALP), osteocalcin (OSC), osteoprotegerin (OPG), receptor activator for nuclear factor κ B ligand (RANKL), type I collagen (Col-I), bone morphogenetic proteins 2 and 7 (BMP-2 and BMP-7), TGF-ß1 and TGF-ß receptors (TGF-ßR1, TGF-ßR2, and TGF-ßR3), and vascular endothelial growth factor (VEGF). Results: Treatment with 150 µg/mL clindamycin significantly increased the gene expression of TFG-ß1, TGF-ßR1, TGF-ßR2, TGF-ßR3, RUNX-2, Col-1, OSX, OSC, BMP-2, BMP-7, ALP, VEGF, and RANKL by HOBs. Treatment with 400 µg/mL amoxicillin significantly increased the gene expression of TGF-ß R1, Col-I, OSC, RANKL, and OPG alone. Conclusion: These findings suggest that 150 µg/mL clindamycin is the decontaminant of choice to treat intraoral bone grafts before their application in bone regeneration. The osteogenic and antibacterial properties of clindamycin can favor and accelerate the integration of bone grafts in the oral cavity.

Influence of different surgical techniques on primary implant stability in the posterior maxilla: a randomized controlled clinical trial.

BACKGROUND AND OBJECTIVE: Primary stability (PS) is remarkable for secondary stability and implant success. Surgical technique modifications seem to improve primary stability, especially in poor quality bone. The aim of this study was to compare the insertion torque (IT) and implant stability quotients (ISQ) of implants placed with underpreparation, expanders, and standard surgical instrumentation in different bone types. MATERIAL AND METHODS: This randomized controlled clinical trial enrolled 108 patients (n=108 implants) distributed in three study groups: group 1 (n=36) underpreparation technique, group 2 (n=36) expander technique, and group 3 (n=36) conventional drilling. IT was recorded with a torque indicator. ISQ was recorded with resonance frequency analysis immediately after surgery. RESULTS: ISQ values were associated with the patient's bone quality and were higher in bone quality type II (76.65) and type III (73.60) and lower in bone quality type IV (67.34), with statistically significant differences (p<0.0001). Lower stability results were obtained when conventional drilling (69.31) was used compared to the use of underpreparation (74.29) or expanders (73.99) with a level of significance of p=0.008 and p=0.005, respectively. CONCLUSIONS: The surgical technique influences the PS when there is low-quality bone. In low-quality bones, conventional drilling obtains lower ISQ values. CLINICAL RELEVANCE: Replace the conventional drilling technique for an alternative, underpreparation or expanders, in low-quality bone in order to achieve greater primary stability.

The Effect of Chlorhexidine, Amoxicillin, and Clindamycin on the Growth and Differentiation of Primary Human Osteoblasts.

PURPOSE: The objective of this study was to determine the effect of two antibiotics (amoxicillin and clindamycin) and one antiseptic (chlorhexidine digluconate [CHX]) on the growth and differentiation capacity of primary human osteoblasts. MATERIALS AND METHODS: Osteoblast proliferation was determined by the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) technique after a 1-minute treatment with 400 µg/mL amoxicillin or 150 µg/mL clindamycin or CHX (0.12% or 0.2%). Flow cytometry was used for apoptosis/necrosis analysis. The study of cell differentiation was performed using a mineralization medium and staining of the nodules formed using red alizarin at 15 and 22 days of treatment with 400 µg/mL amoxicillin or 150 µg/mL clindamycin. Spectrophotometry was used to determine alkaline phosphatase (ALP) activity after 1 minute of treatment. RESULTS: Treatment of osteoblasts with 0.12% and 0.2% CHX for 1 minute induced a strong dose-dependent reduction in cell proliferation (P < .001) with a significant increase in the percentage of apoptotic cells (P = .004 and < .001, respectively). However, cell proliferation significantly increased (P < .05) after treatment with 150 µg/mL clindamycin. Treatment of the osteoblasts with 150 µg/mL clindamycin for 1 minute significantly increased the expression of ALP (P = .002). Calcium deposition was significantly higher (P < .001) in the 150 µg/mL clindamycin group. CONCLUSION: These data support the use of low doses of clindamycin and amoxicillin for intraoral bone graft decontamination and raise questions about the use of CHX. Osteoblast growth and differentiation may be favored by low doses of clindamycin, and it may be the decontaminant of choice for intraoral bone grafts, while CHX is shown as a less bone-friendly agent.

Comparison between Tissue Adhesive Cyanoacrylate and Suture for Palatal Fibromucosa Healing: A Randomized Controlled Study.

Cyanoacrylate tissue adhesive is proposed to promote soft tissue healing in oral surgery and minimize complications (pain, inflammation, and bleeding) associated with wound healing by secondary intention. The objective was to compare cyanoacrylate tissue adhesive (test group) with suture (control group) in terms of postoperative complications, operative time, and wound healing in the palatal donor area after harvesting a de-epithelialized gingival graft. A randomized controlled clinical trial was performed in 24 patients randomly assigned to one of two study groups. Data were gathered on wound bleeding, operative time, postoperative pain, inflammation, hyperesthesia, necrosis, and donor area healing time. Operative time was almost 50% shorter in the tissue adhesive cyanoacrylate group, a significant between-group difference (p = 0.003). Spontaneous bleeding in the donor area during the first 24 h was observed in 11.1% of the tissue adhesive cyanoacrylate group versus 88.9% of the suture group-a significant difference. No significant between-group difference was observed in postoperative pain, inflammation, or degree of healing over time. There were no cases of hyperesthesia or wound necrosis. Utilization of tissue adhesive cyanoacrylate rather than suture in palatal de-epithelialized gingival graft harvesting reduces postoperative bleeding during the first 24 h, as well as the operative time.

Comparison of Implant Stability between Regenerated and Non-Regenerated Bone. A Prospective Cohort Study.

Implant stability is one of the main indicators of successful osseointegration. Although it has been measured in numerous studies, there has been little research on implant stability in regenerated bone. The study compares primary and secondary stability between implants placed in regenerated versus native bone and evaluates the influence of bone quality on the results. Sixty implants were placed in 31 patients: 30 implants inserted in native bone (non-regenerated) after a healing period of at least 6 months post-exodontia and 30 inserted in regenerated bone at 6 months after grafting with xenograft. Resonance frequency analysis (RFA) was used to obtain implant stability quotient (ISQ) values at baseline (implant placement), 8 weeks, and 12 weeks. Statistically significant differences were found between implants placed in regenerated bone and those placed in native bone at all measurement time points (p < 0.05). ISQ values were significantly influenced by bone quality at baseline (p < 0.05) but not at 8 or 12 weeks. Greater stability was obtained in implants placed in native bone; however, those placed in regenerated bone showed adequate primary and secondary stability for prosthetic loading. Bone quality influences the primary but not secondary stability of the implants in both native and regenerated bone.

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

Double-blind, randomized controlled clinical trial on analgesic efficacy of local anesthetics articaine and bupivacaine after impacted third molar extraction.

OBJECTIVE: The objective of this randomized controlled clinical trial (RCT) was to compare the effect of bupivacaine and articaine at habitual doses on pain intensity and the need for analgesics after lower third molar extraction. MATERIALS AND METHODS: The final study sample comprised 50 Caucasian volunteers (26 males and 24 females; age range, 18-30 years) undergoing scheduled surgical extraction of impacted lower third molar. A computer-generated random sequence was used to allocate participants to the articaine (4%) or bupivacaine (0.5%) group. Surgeons and patients were blinded by labeling the articaine and bupivacaine carpules with numbers (1 and 2, respectively). Postoperative pain intensity (primary outcome) was evaluated with a visual analogue scale (VAS), while the requirement for and timing of rescue medication and the quality of intraoperative anesthesia were also measured (secondary outcomes). RESULTS: VAS-measured pain intensity was significantly higher (p < 0.05) in the articaine group than in the bupivacaine group at all time points except for 8 h post-surgery (p = 0.052). Rescue medication was required by 13 (52%) patients in the articaine group and 8 (32%) patients in the bupivacaine group, although the difference did not reach statistical significance (p = 0.252). The groups did not significantly differ (p = 0.391) in the quality of the intraoperative anesthesia. CONCLUSIONS: Bupivacaine is a valid alternative to articaine in third molar surgery and may offer residual anesthesia as a means of reducing postoperative pain. However, further well-designed RCTs are required in larger study populations to verify the effectiveness of bupivacaine to achieve residual analgesia after oral surgery. CLINICAL RELEVANCE: These findings suggest that bupivacaine may be useful as a coadjuvant to control acute postoperative pain. TRIAL REGISTRATION: ACTRN12617001138370.

Long-Term Survival of Dental Implants with Different Prosthetic Loading Times in Healthy Patients: A 5-Year Retrospective Clinical Study.

PURPOSE: To compare survival rates among dental implants restored with immediate, early, and conventional loading protocols, also comparing between maxillary and mandibular implants, and to evaluate the influence of implant length and diameter and the type of prosthesis on treatment outcomes. MATERIALS AND METHODS: This retrospective cohort study initially included all 52 patients receiving dental implants between July 2006 and February 2008 at a private oral surgery clinic in Granada (Southern Spain). Clinical and radiographic examinations were performed, including periapical or panoramic radiographs, and incidences during completion of the restoration were recorded at 1 week, 3 months, 6 months, and at 1, 2, 3, 4, and 5 years. After a 5-year follow-up, 1 patient had died, 3 were lost to follow-up, and 6 required grafting before implant placement; therefore, the final study sample comprised 42 patients with 164 implants. RESULTS: Variables associated with the survival/failure of the restoration were: number of implants (higher failure rate with fewer implants), bone type (higher failure rate in type III or IV bone), and type of prosthesis (higher failure rate with single crowns). No significant association was found in univariate or multivariate analyses between survival rate and the loading protocol, implant length or diameter, or maxillary/mandibular location. CONCLUSIONS: Immediate occlusal loading, immediate provisionalization without occlusal loading, and early loading are viable treatment options with similar survival rates to those obtained with conventional loading. Bone quality and number of implants per patient were the most influential factors.

Effect of Clodronate on Antigenic Profile, Growth, and Differentiation of Osteoblast-Like Cells.

PURPOSE: To evaluate the role of osteoblasts in bisphosphonate-related osteonecrosis of the jaw (BRONJ) by studying the effects of different concentrations of clodronate, a non-nitrogen-containing bisphosphonate, on osteoblast growth, differentiation, and antigenic profile. MATERIALS AND METHODS: Osteoblast-like cells (MG63) were incubated in culture medium with different doses of clodronate. Their proliferative capacity was determined with a spectrophotometric technique (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium assay). Flow cytometry was used to study the antigenic profile. Cell differentiation was evaluated by nodule formation and alkaline phosphatase (ALP) activity was measured by spectrophotometric assay. RESULTS: Clodronate had a significant stimulatory effect on osteoblast-like cell (MG63) proliferation (P < .05). A significant decrease in the expression of CD54, CD80, CD86, and HLA-DR membrane antigens versus controls was observed after 24 hours of treatment with the different clodronate doses assayed (P < .05). A significant decrease (P = .004) in ALP activity was found after 24 hours of treatment with the lowest dose (10(-9) mol/L), and a significant decrease in calcium deposition was found after 15 and 21 days of treatment (P < .05). CONCLUSION: Clodronate increases the proliferation of MG63 osteoblast-like cells and decreases their differentiation capacity, generally at low doses, and modulates the expression of costimulatory molecules associated with immune function. Clodronate exerts its effect on osteoblasts by altering their physiology and impairing their repair capacity, which could be related to the development of BRONJ. However, further research is warranted to elucidate fully the mechanisms by which bisphosphonates can produce this disease.

Factors Affecting Dental Implant Stability Measured Using the Ostell Mentor Device: A Systematic Review.

OBJECTIVES: The aim of this study was to review the literature on factors that may affect dental implant stability as measured with the Ostell mentor device. MATERIALS AND METHODS: A systematic search of the literature was performed in Pubmed, Scopus, and Cochrane databases using dental implants, stability, and resonance frequency analysis as key words. RESULTS: The most relevant randomized controlled trials and clinical trials (n = 39) were selected from among 264 articles. CONCLUSIONS: Many factors can affect dental implant stability as measured with the Ostell mentor device. This may be a useful instrument for deciding the timing of implant loading, but additional research is required to establish the reliability and predictability of resonance frequency analysis for the future osseointegration of dental implants, which remains controversial.

Bacterial contamination levels of autogenous bone particles collected by 3 different techniques for harvesting intraoral bone grafts.

PURPOSE: The aim of this study was to compare levels of bacterial contamination of autogenous bone collected when using low-speed drilling, a back-action chisel, and a bone filter. MATERIALS AND METHODS: Bone tissue samples were taken from 31 patients who underwent surgical extraction of their third lower molars. Before surgical removal of the molar, bone particles were collected by a low-speed drill or a back-action chisel. Then, a stringent aspiration protocol was applied during the ostectomy to collect particulate bone by a bone filter. Processing of samples commenced immediately by incubation in an anaerobic or a CO2-rich atmosphere. The number of colony-forming units (CFUs) was determined at 48 hours of culture. RESULTS: No significant difference in the number of CFUs per milliliter was observed between the low-speed drilling group and the back-action chisel group in the anaerobic or CO2-rich condition (P = .34). However, significantly more micro-organisms were found in the bone filter group than in the low-speed drilling group or the back-action chisel group in the anaerobic and CO2-rich conditions (P < .001). CONCLUSIONS: Particulate bone harvested with low-speed drilling or a back-action chisel is safer for use as an autograft than are bone particles collected with a bone filter. These results suggest that bone obtained from low-speed drilling is safe and straightforward to harvest and could be the method of choice for collecting particulate bone. Further research is needed to lower the bacterial contamination levels of autogenous bone particles used as graft material.

Nitrogen-containing bisphosphonates modulate the antigenic profile and inhibit the maturation and biomineralization potential of osteoblast-like cells.

OBJECTIVES: The aim was to evaluate the effect of three nitrogen-containing bisphosphonates at different concentrations on osteoblast growth, differentiation, and antigenic profile, using the MG-63 cell line as osteoblast model, in order to determine the role of osteoblasts in bisphosphonate-related osteonecrosis of the jaw (BRONJ). MATERIALS AND METHODS: Osteoblasts were incubated in culture medium with 10(-5), 10(-7), or 10(-9) M of pamidronate, alendronate, or ibandronate. Proliferative capacity of the osteoblasts was determined by spectrophotometry (MTT) at 24 and 48 h of culture. Flow cytometry was used to study antigenic profile (CD54, CD80, CD86, HLA-DR) and phagocytic activity. Cell differentiation was evaluated at 7, 15, and 21 days by the study of nodule formation and alkaline phosphatase activity (ALP) at 24 h by spectrophotometric assay. RESULTS: Pamidronate, alendronate, and ibandronate each exerted a significant stimulatory effect on MG63 proliferation that depended on the dose and treatment duration (p < 0.05). In general, a significantly decreased expression of CD54, CD80, and HLA-DR membrane antigens was observed after 24 h of treatment with each nitrogen-containing bisphosphonate (p < 0.05), but there was no significant difference in phagocytic activity versus controls. A decrease in ALP activity was observed after 24 h of treatment and a decrease in calcium deposition after 15 and 21 days (p < 0.05). CONCLUSION: Nitrogen-containing bisphosphonates can increase the proliferation of MG-63 osteoblast-like cells, modulate their expression of co-stimulatory molecules associated with immune function, and decrease their differentiation capacity, generally at low doses. CLINICAL RELEVANCE: These findings suggest that low doses of nitrogen-containing bisphosphonates exert their effect on osteoblasts by altering their physiology, which would explain the disruption of their repair capacity and may be directly related to the development of BRONJ.

Update on the use of corticosteroids in third molar surgery: systematic review of the literature.

OBJECTIVES: Third molar extraction produces inflammation, pain, and trismus, and different pharmacologic therapies have been evaluated for the minimization of postsurgical symptoms. The most frequently prescribed drugs are nonsteroidal anti-inflammatories, followed by steroids and opiates. MATERIAL AND METHODS: A systematic search of the literature was carried out in PubMed, Scopus, MEDLINE, and Cochrane using steroid and third molar as key words. RESULTS: The most relevant randomized controlled trials and meta-analyses (n = 28) were selected from among 72 articles. CONCLUSIONS: Administration of corticosteroids improves the postoperative experience of patients and has a significant impact on trismus and inflammation. Greater effects appear to be achieved by using the parenteral route and by administering the corticosteroid before the surgery.

Proliferation and osteogenic differentiation of osteoblast-like cells obtained from two techniques for harvesting intraoral bone grafts.

OBJECTIVES: The aims of our study were to verify the presence of viable osteoblasts in samples of bone tissue obtained by drilling or from cortico-cancellous bone blocks and to assess their growth and differentiation capacities. MATERIALS AND METHODS: Bone tissue samples were processed independently and cultured in Dulbecco's modified Eagle medium, in a CO2 incubator at 37 °C. The proliferative capacity of osteoblasts was determined by spectrophotometry (MTT) at 24 and 48 h of culture. Cell cycle was analysed by flow cytometry. Cell differentiation was studied by red alizarin staining of nodules formed in mineralisation medium and by analysis of alkaline phosphatase activity. RESULTS: In comparison to bone block-derived osteoblasts, the proliferative capacity was greater at 24 and 48 h of culture (P < 0.001) in the drilling-derived osteoblasts, which showed significantly increased G2/M (P = 0.014) and S (P < 0.001) phases in the cell cycle study. The number of mineralised nodules was proportional to the incubation time, with no differences between the two types of sample, which also did not significantly differ in alkaline phosphatase activity. CONCLUSION: Superior autograft material is obtained by harvesting particulate bone from low-speed drilling fragments than from a cortico-cancellous bone block. CLINICAL RELEVANCE: These results suggest that bone obtained from low-speed drilling is a simple and effective alternative to the classic procedure for obtaining bone tissue.

Aminopeptidase activity profile in cultured human osteoblasts.

Aminopeptidases (APs) are enzymes involved in a wide variety of biological processes and present in a variety of different cell populations. The authors studied these enzymes in primary cultured human osteoblasts in order to establish an activity profile and thereby contribute to knowledge of bone tissue. The authors used 13 different substrates (N-terminal amino acids) and a fluorimetric assay to examine AP activity associated with the membranes of cultured osteoblasts. The authors demonstrated activity > 10 pmol/min/10(4) cells when glycine, alanine, leucine, arginine, phenylalanine, methionine, and lysine were used as substrates. The activity was markedly lower (<1.6 pmol/min/10(4) cells) when the other N-terminal amino acids were used. Puromycin and bestatin inhibited AP activity, though not completely, when we used AlaNA or LeuNA as substrates. Further studies are warranted to determine the role of these enzymes in bone tissue physiology.

Effect of platelet-rich plasma on growth and antigenic profile of human osteoblasts and its clinical impact.

PURPOSE: In recent years, there has been widespread clinical use of platelet-rich plasma (PRP) to facilitate the regeneration of different tissues. However, few data are available on the effect of PRP on parameters other than cell growth. The aim of the present study was to evaluate the effect of PRP on the cell cycle, antigenic profile, and proliferation of primary cultured human osteoblasts. MATERIALS AND METHODS: The cells in the present study were derived from human bone sections obtained from healthy volunteers during third molar surgery. PRP was prepared from human venous blood and used to culture the cell line obtained from the same patient. Flow cytometry was used to study the cell cycle, antigenic profile, and proliferation. RESULTS: The treatment of osteoblasts with PRP modified the expression of CD54, CD80, CD86, and HLA-DR antigens. PRP treatment increased cell proliferation in the short term, but the cell proliferation capacity diminished in the long term, perhaps owing to cell exhaustion. No change in the cell cycle profile was observed in the PRP-cultured cells. CONCLUSIONS: These results suggest that PRP treatment accelerates bone neoformation with no cell cycle changes that might carry a risk of malignant transformation.

Effect of acetaminophen, ibuprofen and methylprednisolone on different parameters of human osteoblast-like cells.

UNLABELLED: Anti-inflammatories are divided between steroidal and non-steroidal drugs according to their chemical nature. They are frequently used in combination to achieve analgesia and reduce inflammation after surgery, especially when bone tissue is affected. However, their effects on bone level are not well known, and results of the scant studies in humans have been contradictory. OBJECTIVE: To study the short-term effect of ibuprofen, acetaminophen and methylprednisolone at therapeutic doses on different cell parameters of human osteoblasts in culture. DESIGN: Osteoblasts were derived from samples of human bone sections obtained during third molar surgery. Cell lines were incubated in culture medium with different concentrations of anti-inflammatories (5 or 25 µM of ibuprofen or acetaminophen, 10(-6) or 10(-8)M of methylprednisolone) for 24 or 48h. Flow cytometry was used to study proliferation, antigenic profile, phagocytic activity and cell cycle. RESULTS: All three anti-inflammatories inhibited osteoblastic proliferation, but no significant cell cycle changes were observed. The drugs had no effect on antigenic profile or phagocytic capacity. CONCLUSION: These results suggest that ibuprofen, acetaminophen and methylprednisolone at therapeutic doses reduce osteoblast growth without affecting other cell parameters, such as antigenic profile or cell cycle. Use of these drugs should be reconsidered in clinical situations that require a rapid healing of bone defects.