Preventive effects of systemic Pistacia eurycarpa Yalt. administration on alveolar bone loss and oxidative stress in rats with experimental periodontitis

Abstract Objective: This study aimed to investigate the effects of systemic administration of P. eurycarpa Yalt. plant extract on alveolar bone loss and oxidative stress biomarkers in gingival tissue in a rat model of experimental periodontitis. Methodology: 32 male Wistar albino rats, weighing 200-250 g, were divided into four groups (n=8): Healthy control (HC), Experimental periodontitis control (EPC), Experimental periodontitis 400 mg/kg (EP400), Experimental periodontitis 800 mg/kg (EP800). Experimental periodontitis was induced using the ligating method. Distilled water was administered to the HC and EPC groups and the plant extract was administered to the EP400 and EP800 groups by oral gavage at doses of 400 mg/kg and 800 mg/kg, respectively. The rats were sacrificed on the 15th day. The values of glutathione peroxidase GSH-Px, malondialdehyde (MDA), superoxide dismustase (SOD), interleukin-1β (IL-1β), interleukin-10 (IL-10), total antioxidant status (TAS), total oxidant status (TOS), oxidative stress index (OSI) in the gingival tissues were analyzed by ELISA tests. Alveolar bone loss was assessed using micro-CT images of the maxilla. Results: Although the IL-1β, TOS, OSI results of the healthy control group were lower than those of the other groups, the TAS values were higher (p<0.05). No significant difference was found in the biochemical parameters among the EPC, EP400, and EP800 groups (p>0.05). Alveolar bone loss was significantly reduced in the extract groups compared to the EPC group (p<0.001). Conclusion: Within the limitations of this study, it was observed that the systemic P. eurycarpa extract application reduced alveolar bone loss in a rat model of experimental periodontitis. Further studies are needed to elucidate the beneficial effects of P. eurycarpa.

Demineralized freeze-dried bone allograft with/without i-Platelet-rich fibrin in 3 wall intrabony defects

Demineralized freeze-dried bone allograft (DFDBA) contains bone morphogenetic proteins (BMPs), hence is osteoinductive. Autologous platelet concentrates exhibit a higher quantity of growth factors. Both these biomaterials aid in bone regeneration when placed in three-wall intrabony defects. However, their efficacy when used alone and in conjugation is not clear. Aim: To assess clinical and radiographic efficacy of injectable platelet-rich fibrin (i-PRF) with microsurgical access flap in the treatment of three-wall intrabony defects in chronic periodontitis patients. Methods: Thirty sites with three-wall intrabony defects were randomly assigned to control and test group by computer generated method. The test group obtained i-PRF mixed with DFDBA while the control group received only DFDBA. Clinical parameters such as site-specific Plaque index (PI), Radiographic intrabony defect depth (IBDD), modified- Sulcular bleeding index (mSBI), Clinical attachment level (CAL), and Probing pocket depth (PPD) were measured at baseline, three and six months. Results: Intragroup comparison within the control group and test group exhibited statistically highly significant variation of mean PI, mSBI, PPD, CAL, and IBDD score from baseline to 3 months and from 3-6 months (p<0.001). However, intergroup comparison demonstrated no statistically significant variation of mean IBDD at all 3 intervals (p>0.05). Conclusion: i-PRF combined with DFDBA enhanced the radiographic and clinical parameters as opposed to DFDBA alone. The role of i-PRF is promising in its capacity for easy obtainability and increased potential to aid in regeneration

The intra- and inter-rater reproducibility of bone level measurements at strategic mini-implants using dental panoramic radiography

Abstract Objectives: This experimental study focused on the intra- and inter-rater reproducibility of vertical bone level (VBL) measurements at strategic mini-implants (MI) using digital panoramic radiographs (PR). Study design: VBLs of 152 MIs for removable partial denture stabilization at 50 randomly chosen PRs from a clinical trial were digitally evaluated by three ratters. Rater deviations exceeding 0.5 mm were re-examined. The intra-class correlation coefficient (ICC) was applied to estimate reliability. The smallest detectable change (SDC) was interrelated to the minimal clinically important change of 0.2 mm. Results: The first measurement round revealed intra- and inter-rater ICCs of > 0.8. However, 28 sites (9 %) were unreadable, and 97 sites (32 %) revealed differences between observers of ≥ 0.5 mm. Following a consensus session and re-training, an additional 8 sites were excluded and all remaining VBL differences were ≤ 0.5 mm. Thus, the SDCs with 95 % credibility were improved from 0.73 to 0.31 mm in the intra-rater and from 1.52 to 0.34 mm in the interrater statistics. Given a 50 % credibility for this special setting, both the intra- and inter-rater SDCs were 0.11 mm. Conclusions: Digital PR can be reliably utilized to determine VBLs around MIs under conditions of at least two trained observers, mutual calibration sessions, and exclusion of unquantifiable radiographs. German Clinical Trials Register ID:DRKS00007589, www.germanctr.de

Partial extraction therapies (PET): a review of the literature / Terapias de extração parcial (TEP): uma revisão da literatura

ABSTRACT One of the most common dental procedures is tooth extraction; however, the bone defect resulting from the process is only partially restored, leading to considerable bone loss. To rehabilitate a fully or partially edentulous patient, we must handle these sites with delicate surgical procedures. There is a large literature presenting attempts to overcome the negative effects of a dental extraction, with the aim of reducing tissue volume loss or restoring the alveolar architecture. In this context, Partial Extraction Therapy (PET) represents a subgroup of interventions to prevent bone loss after extraction using the tooth itself to prevent alveolar bone loss. This literature review aims to make a survey of the published articles on PET, with an emphasis on socket shield technique, and to explain the other techniques such as root burial, pontic-shield and proximal socket-shield, their indications and counter indications in order to deepen the knowledge of these techniques. To identify the included or considered studies, we adopted a detailed search strategy for MEDLINE and Cochrane Library focused in the last 31 years, whose language was English, Spanish or Portuguese. This text presents an analysis of current data regarding the alternatives for alveolar preservation and the installation of immediate implants in these areas, presenting the possibility of a different surgical technique. However, due to the immaturity and lack of conclusive scientific evidence regarding the predictability of the procedures, it is considered that the use of the socket shield technique must be done in an extremely cautious way.

RESUMO Um dos procedimentos odontológicos mais comuns é a extração dentária, contudo, , o defeito ósseo decorrente do processo é apenas parcialmente restaurado, levando a uma perda ossea volumétrica consideravel. Para reabilitar um paciente totalmente ou parcialmente desdentado, devemos manusear estes sitios com intervenções cirúrgicas delicadas. Há uma vasta literatura apresentando tentativas de transpor os efeitos negativos de uma extração dentária, com o objetivo de diminuir a perda volumétrica tecidual ou restaurar a arquitetura alveolar. Neste contexto, a Terapia de Extração Parcial (TEP) representa um subgrupo de intervenções para prevenir a perda óssea após exodontia, usando o próprio dente para prevenir a perda óssea alveolar. Essa revisão de literatura tem por objetivo fazer um levantamento dos artigos publicados sobre as TEP, com ênfase na técnica de socket shield, e explanar a cerca das demais técnicas como sepultamento radicular, pontic-shield e proximal socket-shield, suas indicações e contra-indicações, a fim de aprofundar o conhecimento dessas técnicas. Para a identificação dos estudos inclui?dos ou considerados, adotamos a estrate?gia de busca detalhada para os bancos MEDLINE e Biblioteca Cochrane nos u?ltimos 31 anos, cujo idioma fosse o ingle?s, espanhol ou o portugue?s. Este texto, apresenta uma análise de dados atuais a respeito das alternativas para a preservação alveolar e instalação de implantes imediatos nestas áreas, apresentando a possibilidade de uma técnica cirúrgica diferenciada. No entanto, devido a imaturidade e falta de comprovação cientifica contundente a respeito da previsibilidade dos procedimentos, considera-se que o emprego da técnica de socket shield deve ser feito de forma cautelosa.

CBCT analysis of the relative position between maxillary central incisors and alveolar bone in Southern Chinese adults / 口腔疾病防治

Objective@#Exploring the position and bone wall thickness characteristics of the maxillary central incisors in Southern Chinese adults to provide a clinical reference for the design of immediate maxillary central incisor implantation surgery.@*Methods@#The hospital ethics committee approved the study, and the patients provided informed consent. CBCT images of 990 adult patients (aged 20-79 years) from the Stomatology Hospital (January 2018 to December 2021) were categorized based on the dental arch form and age-sex groups. Sagittal CBCT images of the maxillary central incisors were used to measure the labial and palatal bone thickness wall at 4 mm the CEJ to apical, the middle of the root, and the angle between the tooth long axis and the long axis of the alveolar process, to compare the thickness of the labial and palatal bone walls in samples of male and female patients, and to explore the relationship between the angle between the tooth long axis and the alveolar process long axis in samples of male and female patients in different age groups (20-39 years; 40-59 years; 60-79 years).@*Results@#Significant differences were found in the labiopalatine side of the alveolar bone of the maxillary incisor root position. A total of 95.8% (948/990) of the maxillary incisors were positioned more buccally, 4.1% (41/990) were positioned more midway, and 0.1% (1/990) were positioned more palatally. The thicknesses of the bone wall at the CEJ of 4 mm below the palatal side, the middle of the root, and at the apex were greater (1.82 ± 0.56 mm, 3.20 ± 1.10 mm, and 7.70 ± 2.00 mm, respectively) than those at the labial side (1.21 ± 0.32 mm, 0.89 ± 0.35 mm, and 1.86 ± 0.82 mm, respectively), with statistical significance (P<0.05). Male bone wall thickness was generally greater than female bone wall thickness (P<0.05). The angle between the long axis of male teeth and the alveolar bone was 14.77° ± 5.66°, while that of female teeth was 12.80° ± 5.70°, with a statistically significant difference (P<0.05). The angle between the long axis of teeth and the alveolar bone in the 40-59-year-old group and the 60-79-year-old group was greater than that in the 20-39-year-old group, and the difference was statistically significant (P<0.05).@*Conclusion@#A total of 95.8% of adults in South China have maxillary central incisors with root deviation toward the labial bone cortex. The thickness of the labial bone wall is much thinner than that of the labial bone wall, which is the middle of the thickness of the root. In Southern Chinese adults, the angle between the upper central incisor and the long axis of the alveolar bone in males is greater than that in females, and the degree of the angle increases with age. It is recommended to pay attention to the thickness of the bone wall around the root and the angle between the teeth before immediate implantation surgery to choose a reasonable implantation plan.

Efecto del tratamiento con ácido zoledrónico e hidroxocobalamina sobre la microarquitectura ósea en ratones con periodontitis y osteoporosis inducida: Estudio preclínico / Effect of zoledronic acid and hydroxocobalamin treatment on bone microarchitecture in mice with induced periodontitis and osteoporosis: preclinical study

Objetivo. Evaluar el efecto del tratamiento con ácido zoledrónico e hidroxocobalamina sobre la microarquitectura ósea alveolar en ratones con periodontitis y osteoporosis inducidas. Métodos. Diseño experimental en fase preclínica. Se incluyeron 16 ratones hembras a quienes se les indujo osteoporosis mediante la ovariectomía total y también se indujo la periodontitis por inflamación por ligadura de seda negra 5/0 en el segundo molar maxilar, todos los protocolos fueron sometidos durante anestesia general. Los ratones se distribuyeron en 4 grupos: control, tratamiento con ácido zoledrónico, tratamiento con hidroxocobalamina y tratamiento combinado. A las 16 semanas, se realizó la autanasia, se realizó la disección para la evaluación mediante microtomografía; determinando la densidad mineral ósea (BMD), el volumen de hueso (BV/TV), espesor trabecular (Tb. Th), número de trabéculas (Tb.N), separación trabecular (Tb.Sp); se realizó el análisis descriptivo y bivariado mediante ANOVA de 1 vía considerando un 95% de nivel de confianza. Resultados. El grupo que recibió tratamiento combinado de ácido zoledrónico e hidroxocobalamina presentó mayor densidad mineral ósea (DMO), mayor volumen óseo (BV/TV) y menor separación trabecular (Tb.Sp) en comparación con el grupo de control (p<0,05). Conclusiones. El tratamiento combinado de ácido zoledrónico e hidroxocobalamina mejora las características microarquitectónicas óseas en ratones con osteoporosis y periodontitis inducidas.

Objective. Evaluate the effect of zoledronic acid and hydroxocobalamin treatment on alveolar bone microarchitecture in mice with induced periodontitis and osteoporosis. Methods. Experimental design in preclinical phase. Sixteen female mice were included in which osteoporosis was induced by total ovariectomy and periodontitis was also induced by inflammation by 5/0 black silk ligation of the maxillary second molar, all protocols were performed under general anesthesia. The mice were distributed into 4 groups: control, treatment with zoledronic acid, treatment with hydroxocobalamin and combined treatment. At 16 weeks, euthanasia was performed, dissection was performed for evaluation by microtomography; determining bone mineral density (BMD), bone volume (BV/TV), trabecular thickness (Tb.Th), number of trabeculae (Tb.N), trabecular separation (Tb.Sp); descriptive and bivariate analysis was performed using 1-way ANOVA with a 95% confidence level. Results. The group that received combined treatment of zoledronic acid and hydroxocobalamin presented higher bone mineral density (BMD), higher bone volume (BV/TV) and lower trabecular separation (Tb.Sp) compared to the control group (p<0.05). Conclusions. Combined treatment with zoledronic acid and hydroxocobalamin improves bone microarchitectural features in mice with induced osteoporosis and periodontitis.

Regeneração óssea guiada para aumento horizontal de rebordo utilizando fibrina rica em plaquetas associada a enxertos ósseos: revisão de literatura / Guided bone regenerationfor horizontal bone augmentation using platelet- rich fibrin associated with bone grafts: literature review

Objetivo: revisar a literatura sobre os diferentes tipos de derivados de plaquetas autólogas e o desempenho clínico do uso do sticky bone para aumento ósseo horizontal de rebordo. Materiais e métodos: Para realização dessa revisão foram realizadas buscas nas bases de dados PubMed, Google Scholar e Web of Science, utilizando os seguintes descritores: "platelet-rich fibrin" AND "sticky bone" OR "alveolar bone grafting" AND "sticky bone" OR "guided bone regeneration" AND "sticky bone" AND "alveolar ridge augmentation" OR "Alveolar ridge augmentation" AND "sticky bone". Foram incluídos artigos publicados em inglês, que abordavam conceitos relacionados aos agregados plaquetários e a regeneração óssea guiada para aumento ósseo horizontal de rebordo utilizando fibrina rica em plaquetas associada à enxertos ósseos (sticky bone). Resultados: Após avaliação dos estudos encontrados foram selecionados 11 artigos sobre o uso do sticky bone para aumento horizontal de rebordo. Para compor este trabalho foram selecionados também 14 estudos de revisão e artigos associados ao tema. Por ser de fácil aplicação e obtenção, muitos autores têm estudado as aplicações cirúrgicas do sticky bone e os resultados demonstram que o aumento horizontal do rebordo utilizando essa técnica pode ser realizado de forma previsível. Conclusão: apesar de haver estudos promissores sobre o uso do sticky bone, falta evidência na literatura sobre seu sucesso clínico. Assim, para compreender o potencial regenerativo desta técnica são necessários um maior número de estudos randomizados, com diferentes materiais de enxerto e protocolos padronizados de obtenção do sticky bone.(AU)

Objective: to review the literature on the different types of autologous platelet derivatives and the clinical performance of using sticky bone for horizontal bone ridge augmentation. Materials and methods: In order to conduct this review, it was conducted searches in the PubMed, Google Scholar, and Web of Science databases using the following descriptors: "platelet-rich fibrin" AND "sticky bone" OR "alveolar bone grafting" AND "sticky bone" OR "guided bone regeneration" AND "sticky bone" AND "alveolar ridge augmentation" OR "Alveolar ridge augmentation" AND "sticky bone". It included articles published in English that addressed concepts related to platelet aggregates and guided bone regeneration for horizontal bone augmentation using platelet-rich fibrin associated with bone grafts (sticky bone). Results: After evaluating the studies found, were selected 11 articles on the use of sticky bone for horizontal ridge augmentation. To compose this work, 14 review studies and articles associated with the topic were also selected. Due to its ease of application and availability, many authors have explored the surgical applications of sticky bone, and the results indicate that horizontal ridge augmentation using this technique can be predictably performed. Conclusion: while there are promising studies on the use of sticky bone, the literature lacks evidence regarding its clinical success. Therefore, to fully understand the regenerative potential of this technique, further randomized studies are needed, involving different graft materials and standardized protocols for obtaining sticky bone.(AU)

Use of enamel matrix- derived proteins combined with bone graft for the treatment of intrabony defects: overview of reviews (FRISBEE review) / Uso de proteínas derivadas de la matriz del esmalte combinado con injerto óseo para el tratamiento de defectos intraóseos: resumen estructurado de revisiones sistemáticas (revisión FRISBEE)

Introduction: The use of enamel matrix-derived proteins (EMD) has increased in recent years due to their tissue-inducing properties that support periodontal regeneration. This study is an overview of systematic reviews with FRISBEE methodology on the use of EMD alone or combined with autologous bone graft materials (BGM) in the treatment of intrabony defects. Materials and Methods: A systematic search in the Epistemonikos database was performed. RevMan 5.3 and GRADEpro were used for data analysis and presentation Results: Four systematic reviews and two clinical trials were identified. All studies analysed change in probing depth, clinical attachment level, gingival margin level and bone defect depth (all changes in favour of EMD+BGM groups: mean difference (MD): 0.37 mm more, MD: 0.7 mm more, MD: 0.3 mm less, MD: 0.75 more, respectively). Conclusions: Adding autologous bone graft to EMD to treat intrabony defects showed better results, but not a relevant clinical difference compared to the use of EMD alone.

Introducción: El uso de proteínas derivadas de la matriz del esmalte (EMD) ha aumentado en los últimos años debido a sus propiedades inductoras de tejidos que apoyan la regeneración periodontal. Este estudio es una revisión sistemática de revisiones sistemáticas utilizando metodología FRISBEE sobre el uso de EMD solo o combinado con materiales injerto óseo autólogo (BGM) en el tratamiento de defectos intraóseos. Materiales y Métodos: Se realizó una búsqueda sistemática en la base de datos Epistemonikos. Se utilizaron RevMan 5.3 y GRADEpro para el análisis y la presentación de los datos. Resultados: Se identificaron cuatro revisiones sistemáticas y dos ensayos clínicos. Todos los estudios analizaron el cambio en la profundidad de sondaje, el nivel de inserción clínica, el nivel del margen gingival y la profundidad del defecto óseo (todos los cambios a favor de los grupos EMD+BGM: MD: 0,37 mm más, media de diferencia (MD): 0,7 mm más, MD: 0,3 mm menos, MD: 0,75 más, respectivamente). Conclusión: La adición de injerto óseo autólogo a la EMD para tratar defectos intraóseos mostró mejores resultados, pero no una diferencia clínica relevante en comparación con el uso de la EMD sola.

Serum nitric oxide concentration in generalized chronic and aggressive periodontitis in the Mexican population is not related to the severity of the disease / La concentración de óxido nítrico en suero de pacientes con periodontitis agresiva y crónica generalizada no está relacionada con la gravedad de la enfermedad

Introduction: Periodontitis is an inflammatory disease that affects the supporting tissues of teeth, the effects of excess of nitric oxide, may contribute to the symptoms of periodontitis. Objective: To determine the serum nitric oxide concentration in generalized chronic and aggressive periodontitis patients and to compare it with a healthy subject group from the Mexican population. Materials and methods: A case and control study was performed. Sixty-nine individuals were recruited from the Clínica de Posgrado de Periodoncia of the Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, México. Patients with clinical features of generalized chronic periodontitis (GCP group, n=19), generalized aggressive periodontitis (GAP group, n=11), and a group of healthy subjects (HS group, n=39) were included in the study. Informed consent was obtained from each subject, and serum nitric oxide concentration was measured by an enzyme-linked immunosorbent assay. Results: Nitric oxide concentration in the study groups was greater in the GCP group (462.57 ± 16.57 µmol/L) than in the GAP group (433.84 ± 18.61 µmol/L) and the HS group (422.46 ± 12.07 µmol/L). A comparison using Student's t-test (one-tailed) between healthy subjects and generalized chronic periodontitis showed borderline significance (p<0.04), whereas no significant differences were observed in HS and GAP groups, with a p-value of 0.64, and the GAP vs. GCP p-value was 0.33. Conclusion: The serum nitric oxide concentration observed in the present study suggests that nitric oxide plays a major role in the inflammatory process, which cannot necessarily be linked to the severity of the disease and periodontal tissue destruction.

Introducción. La periodontitis es una enfermedad inflamatoria que afecta los tejidos de soporte dental; los efectos del exceso de óxido nítrico pueden contribuir a los síntomas de la periodontitis. Objetivo. Determinar la concentración de óxido nítrico en el suero de los pacientes con periodontitis agresiva y crónica generalizada, y compararla con la de individuos sanos de población mexicana. Materiales y métodos. Se trata de un estudio de casos y controles. Se incluyeron 69 individuos de la Clínica de Posgrado de Periodoncia del Centro Universitario de Ciencias de la Salud de la Universidad de Guadalajara. Se dividieron en tres grupos: pacientes con periodontitis crónica generalizada (GCP, n=19), pacientes con periodontitis agresiva generalizada (GAP, n=11) e individuos sanos periodontalmente (HS, n=39). Se obtuvo el consentimiento informado de todos los participantes. Se utililizó la prueba ELISA para medir la concentración de óxido nítrico en suero. Resultados. Las concentraciones de óxido nítrico observadas fueron mayores en el grupo GCP (462,57 ± 16,57 µmol/L) que en los grupos GAP (433,84 ± 18,61 µmol/L) y HS (422,46 ± 12,07 µmol/L). La comparación entre HS y GCP mediante la prueba estadística t de Student (una cola), mostró diferencias significativas (p<0,04), y no se observaron diferencias entre los grupos HS y GAP (p=0,64), ni entre GAP y GCP (p=0,33). Conclusiones. La concentración de óxido nítrico en suero, observada en el presente estudio, sugiere que el óxido nítrico desempeña un importante papel en el proceso inflamatorio, lo que no necesariamente está ligado a la gravedad de la enfermedad ni a la destrucción del tejido periodontal.

The role of adiponectin in type 2 diabetes-related periodontitis / 口腔疾病防治

@#Adiponectin, an adipocytokine secreted by adipocytes, has emerged as a potential treatment agent for type 2 diabetes. Adiponectin plays a variety of physiological roles in regulating glucolipid metabolism, oxidative stress, inflammatory responses and bone metabolism by binding to its receptors expressed on a variety of cells and tissues. Numerous studies have confirmed the strong association of adiponectin with type 2 diabetes-related periodontitis. Adiponectin can improve systemic insulin resistance by increasing insulin sensitivity and promoting insulin secretion. It improves the periodontal inflammatory response by inhibiting the expression of proinflammatory cytokines induced by Porphyromonas gingivalis lipopolysaccharide and promoting M2-type polarization of macrophages. In addition, adiponectin inhibits osteoclast differentiation and maturation through various pathways, such as Wnt/β-catenin and NF-κ, and promotes osteoblast differentiation to regulate bone metabolism, thus improving periodontal bone resorption and destruction. Therefore, adiponectin is expected to become a therapeutic target for type 2 diabetes-related periodontitis. Due to the physiological characteristics of adiponectin, its clinical application has been somewhat limited. This article reviews the latest research progress on adiponectin in type 2 diabetes-related periodontitis, aiming to elucidate the possible effects of adiponectin on type 2 diabetes-related periodontitis in terms of glycemic control, anti-inflammation and bone metabolism and to provide some opinions on the treatment of this disease and the development of relevant drugs.

Research progress on anterior alveolar bone changes after orthodontic treatment involving extractions / 口腔疾病防治

@#It has been traditionally believed that a 1:1 cortical bone remodeling/tooth movement ratio has been preserved during orthodontic treatment for tooth movement, with the alveolar bone on the tension side growing and the alveolar bone on the pressure side resorbing to maintain the balance of the alveolar bone. However, recent studies have shown that alveolar bone loss has been found in patients who have undergone orthodontic treatment, suggesting that the alveolar bone does not change as the teeth change over time. Whether the morphology of the alveolar bone will change when the anterior teeth are moved has been the clinical focus. The changes of anterior alveolar bone in patients who have undergone tooth extraction after orthodontic treatment were summerized by literature review in this paper. The results of the review showed that the alveolar bone at the lingual/palatal root-cervical site of the anterior root is more prone to bone loss after extensive movement of the anterior teeth. With the development of imaging technology, CBCT is now more commonly used for analysis instead of two-dimensional images for measurement, as its results are more accurate. However, there are few multifactorial studies in which CBCT has been used to assess the morphological changes in the alveolar bone. The focus of future research is to compare the long-term changes in the anterior alveolar bone of patients of different ages based on three-dimensional imaging, and to study the correlation between different skeletal features, tooth movement patterns and alveolar bone remodeling.

Research progress on "sandwich" osteotomy to increase alveolar bone / 口腔疾病防治

@#Lack of alveolar bone height is a major challenge for dental implants. In recent years, the use of "sandwich" osteotomy to increase alveolar bone height has become a topic of discussion within the research community. In theory, "sandwich" osteotomy is a U-shaped osteotomy in the bone defect area, to preserve the blood supply of the mucoperiosteal on the lingual side and to create an artificial "four-wall bone bag" to build a favorable space for osteogenesis and to increase the height of the alveolar bone. Histological studies have shown that the osteogenesis speed of "sandwich" osteotomy is fast, and the bone is good. Sandwich osteotomy is suitable for buccal-lingual alveolar bone height defects less than 50% of the implant length or for unilateral defects more than 50% of the implant length. In the operation of "sandwich" osteotomy, the horizonal incision should be 10-12 mm below the crest of the buccal alveolar ridge. The design of the osteotomy line should ensure the height of the osteotomy block and that the mandibular canal does not sustain damage and that it fits the shape of the bone defect. There was no significant difference in the osteogenic effect of different types of bone graft materials used for "sandwich" osteotomy. The osteotomy block was rigorously fixed by a titanium plate, titanium nail, implant and other materials, and finally, the intraoperative area was tensioned and sutured. The effect of bone augmentation was evaluated and compared with other bone augmentation techniques; the evaluation showed that sandwich osteotomy was better for moderate vertical bone defects. This technique is highly sensitive and postoperative transient sensory loss is common. With advances in technology, the application of digital technology and ultrasonic bone knives, the risk of complications is greatly reduced and advances in digital osteotomy will promote apply of "sandwich" osteotomy, which will become a popularized technique for clinical alveolar bone augmentation.

Alveolar and mandibular cortex bone status in individuals with type 1 diabetes mellitus: a cross-sectional paired study / Condição óssea alveolar e da cortical mandibular em indivíduos com diabetes mellitus tipo 1: um estudo transversal pareado

Aim: This study compared alveolar bone loss, teeth with furcation, and mandibular cortical modification between individuals with type 1 diabetes mellitus (T1DM) and nondiabetic individuals. Methods: Radiographs of 50 T1DM individuals and 100 nondiabetic individuals were examined to evaluate the presence of teeth with furcation, alveolar bone loss, and mandibular cortical modifications. The Mann-Whitney, Chi-square, and Student's t tests were used to analyze personal characteristics and bone status. Linear and logistic regression was performed to explore associations. Results: A significant difference was observed in the average number of teeth with furcation and in the median of alveolar bone loss between T1DM and the nondiabetic participants. T1DM individuals are more likely to have alveolar bone loss (OR = 3 2.250), teeth with furcation (OR = 8.903), and mandibular cortical modification (OR = 15.667) than are nondiabetic individuals. Among T1DM individuals, the glycemic control has a high influence in mandibular cortical modifications (p < 0.05). Conclusions: A high association between uncontrolled blood glucose and mandibular cortical modifications was observed among T1DM individuals. Alveolar bone loss of T1DM individuals was associated with age, time of diagnosis, glycemic control, and the existence of chronic complications.

Objetivo:Comparar a perda óssea alveolar, a presença de dentes com lesão de furca e a alteração da cortical óssea entre indivíduos com DMT1 e indivíduos não-diabéticos. Métodos: Foram examinadas radiografias de 50 indivíduos diabéticos e de 100 não-diabéticos para avaliar a presença de dentes com lesão de furca, perda óssea alveolar e alteração cortical mandibular. Para analisar as características individuais e as condições ósseas foram usados os testes de Mann-Whitney,Qui-quadrado e t de Student. Regressões linear e logística foram realizadas para identificar associações. Resultados: Foi encontrada diferença significativa na média de dentes com lesão de furca e na mediana da perda óssea alveolar entre diabéticos e não-diabéticos. Indivíduos com DMT1 possuem mais chance de apresentar perda óssea alveolar (OR = 32,250), lesão de furca (OR=8,903) e alteração da cortical mandibular (OR = 15,667) em comparação aos indivíduos não-diabéticos. Entre os diabéticos, o controle da glicemia possui grande influência nas alterações da cortical mandibular (p < 0,05). Conclusões: Existe uma alta associação entre os níveis de glicemia descontrolada e alterações na cortical mandibular entre os indivíduos com DMT1. A perda óssea alveolar de indivíduos com DMT1 foi associada aos fatores idade, tempo de diagnóstico, controle da glicemia e a presença de complicações crônicas.

Spontaneous spheroids from alveolar bone-derived mesenchymal stromal cells maintain pluripotency of stem cells by regulating hypoxia-inducible factors

BACKGROUND: Spontaneous spheroid culture is a novel three-dimensional (3D) culture strategy for the rapid and efficient selection of progenitor cells. The objectives of this study are to investigate the pluripotency and differentiation capability of spontaneous spheroids from alveolar bone-derived mesenchymal stromal cells (AB-MSCs); compare the advantages of spontaneous spheroids to those of mechanical spheroids; and explore the mechanisms of stemness enhancement during spheroid formation from two-dimensional (2D) cultured cells. METHODS: AB-MSCs were isolated from the alveolar bones of C57BL/6 J mice. Spontaneous spheroids formed in low-adherence specific culture plates. The stemness, proliferation, and multi-differentiation capacities of spheroids and monolayer cultures were investigated by reverse transcription quantitative polymerase chain reaction (RT-qPCR), immunofluorescence, alkaline phosphatase (ALP) activity, and oil-red O staining. The pluripotency difference between the spontaneous and mechanical spheroids was analyzed using RT-qPCR. Hypoxia-inducible factor (HIFs) inhibition experiments were performed to explore the mechanisms of stemness maintenance in AB-MSC spheroids. RESULTS: AB-MSCs successfully formed spontaneous spheroids after 24 h. AB-MSC spheroids were positive for MSC markers and pluripotency markers (Oct4, KLF4, Sox2, and cMyc). Spheroids showed higher Ki67 expression and lower Caspase3 expression at 24 h. Under the corresponding conditions, the spheroids were successfully differentiated into osteogenic and adipogenic lineages. AB-MSC spheroids can induce neural-like cells after neurogenic differentiation. Higher expression of osteogenic markers, adipogenic markers, and neurogenic markers (NF-M, NeuN, and GFAP) was found in spheroids than in the monolayer. Spontaneous spheroids exhibited higher stemness than mechanical spheroids did. HIF-1α and HIF-2α were remarkably upregulated in spheroids. After HIF-1/2α-specific inhibition, spheroid formation was significantly reduced. Moreover, the expression of the pluripotency genes was suppressed. CONCLUSIONS: Spontaneous spheroids from AB-MSCs enhance stemness and pluripotency. HIF-1/2α plays an important role in the stemness regulation of spheroids. AB-MSC spheroids exhibit excellent multi-differentiation capability, which may be a potent therapy for craniomaxillofacial tissue regeneration.

Pro-angiogenic photo-crosslinked silk fibroin hydrogel: a potential candidate for repairing alveolar bone defects

Abstract Objective: This study aimed to develop a pro-angiogenic hydrogel with in situ gelation ability for alveolar bone defects repair. Methodology: Silk fibroin was chemically modified by Glycidyl Methacrylate (GMA), which was evaluated by proton nuclear magnetic resonance (1H-NMR). Then, the photo-crosslinking ability of the modified silk fibroin was assessed. Scratch and transwell-based migration assays were conducted to investigate the effect of the photo-crosslinked silk fibroin hydrogel on the migration of human umbilical vein endothelial cells (HUVECs). In vitro angiogenesis was conducted to examine whether the photo-crosslinked silk fibroin hydrogel would affect the tube formation ability of HUVECs. Finally, subcutaneous implantation experiments were conducted to further examine the pro-angiogenic ability of the photo-crosslinked silk fibroin hydrogel, in which the CD31 and α-smooth muscle actin (α-SMA) were stained to assess neovascularization. The tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) were also stained to evaluate inflammatory responses after implantation. Results: GMA successfully modified the silk fibroin, which we verified by our 1H-NMR and in vitro photo-crosslinking experiment. Scratch and transwell-based migration assays proved that the photo-crosslinked silk fibroin hydrogel promoted HUVEC migration. The hydrogel also enhanced the tube formation of HUVECs in similar rates to Matrigel®. After subcutaneous implantation in rats for one week, the hydrogel enhanced neovascularization without triggering inflammatory responses. Conclusion: This study found that photo-crosslinked silk fibroin hydrogel showed pro-angiogenic and inflammation inhibitory abilities. Its photo-crosslinking ability makes it suitable for matching irregular alveolar bone defects. Thus, the photo-crosslinkable silk fibroin-derived hydrogel is a potential candidate for constructing scaffolds for alveolar bone regeneration.

Exercise improves alveolar bone loss and the inflammatory profile of periodontal disease / El ejercicio mejora la pérdida de hueso alveolar y el perfil inflamatorio de la enfermedad periodontal / O exercício melhora a perda de osso alveolar e o perfil inflamatório da doença periodontal

ABSTRACT Periodontal disease (PD) is an inflammatory oral disease and alveolar bone loss is the most important sign of PD. However, the effects of exercise on inflammatory factors and alveolar bone loss in individuals with PD have been little studied. This meta-analysis assesses the effect of physical exercise on alveolar bone loss (ABL) and the inflammatory profile of PD in animal models. Relevant studies published through July 2020 in PubMed, Medline, Embase and Web of Science were searched after developing a PICOS statement. Quality assessment and risk of bias were analyzed according to the SYRCLE protocol. A total of 52 references were retrieved, 4 of which were considered eligible for inclusion. A total of thirty-four male Wistar rats from the included studies were evaluated for alveolar bone loss and assessed for inflammatory profile. The results indicated that physical exercise could reduce alveolar bone loss (95% CI -2.85 to -0.82, p = 0.002) and the pro-inflammatory tumor necrosis factor-α (TNF-α) in serum or gingival tissue (95% CI -0.45 to -0.24, p < 0.00001). Inversely, exercise increased anti-inflammatory interleukin-10 (IL-10) in serum or gingival tissue (95% CI 0.28 to 0.69, p < 0.00001). However, one study reported a negative result in the expression of TNF-α and IL-10. Current evidence indicates that physical exercise contributes to ameliorate PD by reducing alveolar bone loss and inflammation in animal PD models, which suggests that moderate exercise can be implemented in clinical practice to maintain periodontal health. Level of Evidence I; Systematic Review and Meta-analysis

RESUMEN La enfermedad periodontal (EP) es una enfermedad inflamatoria oral y la pérdida de hueso alveolar es su signo más importante. Sin embargo, los efectos del ejercicio sobre los factores inflamatorios y la pérdida ósea alveolar en individuos con EP han sido poco estudiados. Este meta-análisis evalúa el efecto del ejercicio sobre la pérdida ósea alveolar (POA) y el perfil inflamatorio de la EP en modelos animales. Se llevaron a cabo estudios relevantes publicados hasta julio de 2020 en PubMed, Medline, Embase y Web of Science tras desarrollar la investigación con el método PICO. La evaluación de la calidad y el riesgo de sesgo se analizaron según el protocolo SYRCLE. Se recuperó un total de 52 referencias, cuatro de las cuales se consideraron elegibles para su inclusión. En un total de 34 ratas Wistar macho de los estudios incluidos se evaluó la pérdida de hueso alveolar y el perfil inflamatorio. Los resultados indicaron que el ejercicio puede reducir la pérdida de hueso alveolar (IC del 95%: -2,85 a -0,82; p = 0,002) y el factor de necrosis tumoral proinflamatorio-α (TNFα) en suero o tejido gingival (IC del 95%: -0,45 a -0,24; p < 0,00001). Por el contrario, el ejercicio aumentó la interleucina-10 (IL-10) antiinflamatoria en el suero o en el tejido gingival (IC del 95%: 0,28 a 0,69; p < 0,00001). Sin embargo, un estudio informó de un resultado negativo en la expresión de TNFα e IL-10. Las pruebas actuales indican que el ejercicio contribuye a mejorar la EP al reducir la pérdida de hueso alveolar y la inflamación en modelos animales de EP, lo que sugiere que se puede implementar el ejercicio moderado en la práctica clínica para mantener la salud periodontal. Nivel de Evidencia I; Revisión Sistemática y Meta-análisis.

RESUMO A doença periodontal (DP) é uma doença inflamatória oral e a perda óssea alveolar é seu sinal mais importante. No entanto, os efeitos do exercício sobre os fatores inflamatórios e a perda óssea alveolar em indivíduos com DP têm sido pouco estudados. Esta metanálise avalia o efeito do exercício físico sobre a perda óssea alveolar (POA) e o perfil inflamatório da DP em modelos animais. Estudos relevantes publicados até julho de 2020 em PubMed, Medline, Embase e Web of Science foram pesquisados depois de desenvolver a pesquisa com o método PICO. A avaliação da qualidade e o risco de viés foram analisados de acordo com o protocolo SYRCLE. Um total de 52 referências foram recuperadas, quatro das quais foram consideradas elegíveis para inclusão. Um total de 34 ratos Wistar machos dos estudos incluídos foram avaliados quanto à perda de osso alveolar e avaliados quanto ao perfil inflamatório. Os resultados indicaram que o exercício físico pode reduzir a perda de osso alveolar (IC 95% -2,85 a -0,82, p = 0,002) e o fator de necrose tumoral pró-inflamatório-α (TNFα) no soro ou tecido gengival (IC 95% -0,45 a -0,24, p < 0,00001). Inversamente, o exercício aumentou a interleucina-10 anti-inflamatória (IL-10) no soro ou no tecido gengival (IC 95% 0,28 a 0,69, p < 0,00001). Contudo, um estudo relatou resultado negativo na expressão de TNFα e IL-10. As evidências atuais indicam que o exercício físico contribui para melhorar a DP, reduzindo a perda de osso alveolar e a inflamação em modelos animais de DP, o que sugere que o exercício moderado pode ser implementado na prática clínica para manter a saúde periodontal. Nível de Evidência I; Revisão Sistemática e Metanálise.

Two-stage alveolar bone grafting for nasal floor reconstruction in adult cleft patients / 华西口腔医学杂志

Alveolar cleft is one of the key links of cleft lip and palate reconstruction due to its close relationship with tooth and jaw coordination and nasolabial deformity. The alveolar bone graft repairs the hole in the gum ridge and stabilizes the bone arch, providing better support for the base of the nose and new bone for the roots of the developing teeth to grow into. Unfortunately, bone graft failure in the traditional way, even among minor clefts, bony hypoplasia, or absence that affects the nasal base and piriform rim, is common. Two-stage alveolar bone grafting, which has advantages in addressing the underlying skeleton and deficiency, could be an optional surgical procedure for nasal floor reconstruction in adult patients with a broad alveolar cleft.

Effects of atractylodin on inflammatory damage of periodontal tissue and alveolar bone loss in periodontitis rats and its mechanism / 中国药房

OBJECTIVE To investigate the effects and mechanism of atractylodin on inflammatory injury of periodontal tissue and alveolar bone loss in periodontitis rats. METHODS A total of 144 SD rats were divided into control group （intragastric and intraperitoneal injection of normal saline）， model group （intragastric and intraperitoneal injection of normal saline）， atractylodin low-dose， medium-dose and high-dose groups （intraperitoneal injection of 6.665， 13.33， and 26.66 mg/kg atractylodin）， metronidazole group （positive control group， intragastric injection of 0.05 g/kg metronidazole， intraperitoneal injection of normal saline）， AMD3100 [stromal cell-derived factor-1 （SDF-1）/CXC chemokine receptor-4 （CXCR4） pathway inhibitor] group （intragastric injection of 1 mg/kg AMD3100， intraperitoneal injection of normal saline）， atractylodin high-dose+AMD 3100 group （intraperitoneal injection of 26.66 mg/kg atractylodin， intragastric injection of 1 mg/kg AMD3100）， with 18 rats in each group. Except for the control group， all other groups of rats were inoculated with Porphyromonas gingivalis to construct a periodontitis model. After successful modeling， they were given relevant medicine or normal saline， once a day， for 4 consecutive weeks. The gingival index of rats was detected； the levels of interleukin-6 （IL-6） and tumor necrosis factor α （TNF-α） in rat serum were also determined； alveolar bone resorption， periodontal histopathologic changes and the number of osteoclasts were detected by methylene blue staining， HE staining and TRAP staining， respectively. The expressions of osteoprotegerin （OPG）， receptor activator of NF-κB ligand （RANKL）， SDF-1 and CXCR4 proteins were determined. RESULTS Compared with the control group， serious pathological injury of periodontal tissue was found in the model group， the gingival index， the levels of IL-6 and TNF- α， alveolar bone absorption value， the number of osteoclasts， and the expression of RANKL protein were all increased significantly （P＜0.05）， while the expressions of OPG， SDF-1 and CXCR4 proteins were decreased significantly （P＜0.05）. Compared with the model group， pathological injury of periodontal tissue in rats was reduced； the gingival index， the levels of IL-6 and TNF-α， alveolar bone resorption value， osteoclast number and RANKL protein expression were decreased significantly， while protein expressions of OPG， SDF-1 and CXCR4 were increased significantly in atractylodin low-dose， medium-dose and high-dose groups and metronidazole group （P＜0.05）. The change trend of corresponding indexes in the AMD3100 group was opposite to the above （P＜0.05）. AMD3100 attenuated the inhibitory effect of high-dose atractylodin on inflammatory response and alveolar bone loss in rats with periodontitis （P＜0.05）. CONCLUSIONS Atractylodin may improve the inflammatory response and alveolar bone loss in periodontitis rats by activating the SDF-1/CXCR4 signaling pathway.

Expression of Stro-1, Runx-2, Osterix, and Alp in Alveolar Bone Regeneration Process Following the Administration of Hydroxyapatite Gypsum Puger (HAGP) Scaffold

@#Introduction: Tooth extraction before denture placement could result in trauma and damage to up to 50% of the alveolar bone, inducing bone resorption, and affecting the patient’s quality of life. Hydroxyapatite Gypsum Puger (HAGP) can be used as an alternative to bone graft material which degrades slowly, affecting the proliferation and activity of cells that are responsible for bone tissue engineering. This study aimed to analyze the regeneration mechanism of alveolar bone by administering the HAGP scaffold and observing the Stro-1, Runx-2, Osterix, and ALP expression. Methods: Laboratory experimental research was conducted and we used 150-355µm HAGP scaffold particles, applied in vivo inside alveolar sockets of the rats for 7, 14, and 28 days, followed by immunohistochemical examination of Stro-1, Runx-2, Osterix, and ALP expressions. Results: The HAGP scaffold group showed that the Stro-1 expression was significantly higher than the K(-) group, and the Runx-2 expression increased on day 7 and decreased on day 28 in the HAGP and K(-) groups. Osterix expression increased from day 7, 14, to day 28. The high expression of Osterix on day 28 means it took over the Runx-2 function. In ALP there was a significant increase on day 7. ALP expression was a sign of early osteoblast differentiation and production by cells, this extracellular matrix mineralization is an indicator of the osteogenic process. Conclusion: Alveolar bone regeneration mechanism in rats revealed that the expression of Stro-1, Runx-2, Osterix, and ALP was higher in the HAGP scaffold group compared to the control group on days 7,14, and 28.

Anthropometric Evaluation of Labial Alveolar Bone Dimension of Maxillary Anterior Teeth in Kuantan Population: A ConeBeam Computed Tomography Study

@#Introduction: Labial bone with adequate height and width is crucial for an implant to be successfully placed and ensure the stability of treatment outcome in the long term. The objective of this study was to employ cone-beam computed tomography (CBCT) assessment in evaluating the differences in labial alveolar bone morphology among the Kuantan population in Malaysia. Methods: A total of 60 images taken from Kulliyyah of Dentistry, International Islamic University Malaysia, between 2009 and 2019 were analysed. The root diameter, labial and palatal plate thickness, the labial bony curvature angle beneath the root apex, and the distance from the deepest point of labial bony curvature to the root apex were all measured on each of the maxillary anterior teeth. Results: At 3 mm below the cementoenamel junction, the mean (± standard deviation; SD) thickness of the labial plate for maxillary anterior teeth was 1.45 ± 0.62 mm, 1.38 ± 0.50 mm, and 1.61 ± 0.66 mm for the lateral incisor, central incisor, and canine, respectively. Below the root apex, the labial bony curvature angle was 233.63 ± 17.74 for the central incisor, 235.68 ± 17.74 for the lateral incisor and 233.81 ± 11.09 for the canine. Discussion: The result revealed a favourable labial plate in the Kuantan population when implant in the aesthetic zone is planned. Conclusion: Labial alveolar bone thickness of the Kuantan population was thin within 1.5 mm while the palatal plate was thick. Overall, labial alveolar bone was present within 3 mm below the cementoenamel junction. The labial bony curvature was highest and most curved for the central incisor compared to the lateral incisor and canine.