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

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.

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.

Prevalence and extent of Alveolar dehiscence and fenestration in Class I hyperdivergent subjects with different buccolingual inclinations of maxillary molar teeth: a CBCT study

Buccolingual position of teeth could affect the prevalence of alveolar bone defects. Presence of alveolar defects may have a deleterious effect on orthodontic treatment. The aim was to assess the prevalence and extent of dehiscence and fenestration in Class I hyperdivergent subjects and correlate it with buccolingual inclinations(BL) of maxillary first molar teeth. Methods: This retrospective study involved 80 CBCTs of class I hyperdivergent subjects divided into two groups - group A (n=33) buccolingual inclination >9º and group B (n=47) buccolingual inclination <9º. Prevalence and extent of alveolar bone dehiscence and fenestrations were measured in CBCTs using OSIRIX Lite software. Descriptive statistics, Mann Whitney U test and Spearman correlation were done for evaluating intergroup differences and correlation with Buccolingual inclination. Results: Overall prevalence of dehiscence and fenestration in maxillary first molars was 60.95% and 5% respectively. In the buccal alveolar bone, prevalence of dehiscence was highest in group A (84.6%) for 16 and in the lingual alveolar bone prevalence of dehiscence was highest in group B (71.4%) for 26 . On intergroup comparison, the extent of lingual alveolar bone dehiscence (26) in group B was significantly higher (p value <0.05) than in group A. No significant correlation between the extent of dehiscence and fenestration with buccolingual inclination of molar teeth was noted. Conclusion: Molar teeth with BL inclinations of more than 9º had higher prevalence of dehiscence on the buccal side and molar teeth with BL inclinations less than 9 degrees had more dehiscence on the lingual side. But no significant correlation of BL inclination with prevalence and extent of dehiscence and fenestration was noted

Clinical efficacy of simple taper retentive implants in immediate posterior dental implantation for 5-7 years / 华西口腔医学杂志

OBJECTIVES@#This study aimed to evaluate the long-term clinical efficacy of simple taper retentive implants in the posterior dental area after immediate implantation for 5-7 years.@*METHODS@#Selected from January 2015 to December 2017 in the Fourth Affiliated Hospital of Nanchang University dental clinic line tooth area immediately after the implant prosthesis, a total of 38 patients, 53 implants, were deep into (bone under 2 mm or higher) and the upper structure was repaired. In addition, after the completion of tracking observation of 60-90 months, the implant surrounding bone health was recorded and analyzed.@*RESULTS@#After 5-7 years of follow-up, 1 of the 53 implants failed to fall out, and the implant retention rate was 98.1%. The amount of bone resorption in the proximal and distal margins 5-7 years after implant restoration was (0.16±0.94) mm and (-0.01±1.29) mm, respectively, and the difference in bone height between the proximal and distal margins of the implant and the immediate post-restoration period was not statistically significant (P>0.05). No statistically significant differences were found in the effects of periodontitis, implant site inflammation, and smoking on peri-implant marginal bone resorption (P>0.05).@*CONCLUSIONS@#The single taper-retained implant broadens the indications for immediate implant placement in the posterior region, and its deep sub-osseous placement (≥2 mm below the bone) avoids to a certain extent the disturbance of the implant by external stimuli and the exposure of the cervical abutment of the implant, with the good long-term stability of the marginal bone around the implant.

Effect of dental follicles in minimally invasive open-eruption technique of labially impacted maxillary central incisors / 华西口腔医学杂志

OBJECTIVES@#To summarize the open-eruption technique of impacted anterior maxillary teeth, this study reports a technically improved operation on surgical exposure based on dental follicles and evaluates post-treatment periodontal health considering the effect of dental follicles.@*METHODS@#Patients who underwent open-eruption technique with unilateral labially impacted maxillary central incisors were selected. The impacted teeth were assigned to the experimental group, and the contralateral unimpacted maxillary central incisors were assigned to the control group. In the surgical exposure, the new technique makes use of dental follicles to manage the soft tissue, so as to preserve soft tissue for better aesthetic results and healthier periodontal tissue. Tooth length, root length, alveolar bone loss, and alveolar bone thickness were recorded after the therapy.@*RESULTS@#A total of 17 patients with unilateral maxillary central incisor impaction were successfully treated. The tooth length and root length of the two groups showed a statistically significant difference between the impacted and homonym teeth, with a shorter length in the impacted tooth (P<0.05). More labial alveolar bone loss was found in the experimental group compared with that in the control group (P<0.05). The outcomes of the cementoenamel junction width, pa- latal alveolar bone loss, and alveolar bone thickness did not indicate statistical significance between the experimental and control groups (P>0.05).@*CONCLUSIONS@#In the surgical exposure, the new technique uses dental follicles to manage the soft tissue and preserve it for better aesthetic results and healthier periodontal tissues.

Oligonucleotide drugs and their progress in stomatology / 中华口腔医学杂志

Oligonucleotide drugs have the characteristics of targeting, modifiability and high biosafety. Recent studies have shown that oligonucleotide can be used to make biosensors, vaccine adjuvants, and has the functions of inhibiting alveolar bone resorption, promoting jaw and alveolar bone regeneration, anti-tumor, destroying plaque biofilm, and precise control of drug release. Therefore, it has a broad application prospect in the field of stomatology. This article reviews the classification, action mechanism and research status of oligonucleotide in stomatology. The aim is to provide ideas for further research and application of oligonucleotide.

Comparison of three methods for establishing rat peri-implantitis model / 北京大学学报(医学版)

OBJECTIVE@#To compare the efficiency and effect of establishing rat peri-implantitis model by traditional cotton thread ligation and local injection of Porphyromonas gingivalis lipopolysaccharide (LPS) around the implant, as well as the combination of the two methods.@*METHODS@#Left side maxillary first molars of 39 male SD rats were extracted, and titanium implants were implanted after four weeks of healing. After 4 weeks of implant osseointegration, 39 rats were randomly divided into 4 groups. Cotton thread ligation (n=12), local injection of LPS around the implant (n=12), and the two methods combined (n=12) were used to induce peri-implantitis, the rest 3 rats were untreated as control group. All procedures were conducted under 5% isoflurane inhalation anesthesia. The rats were sacrificed 2 weeks and 4 weeks after induction through carbon dioxide asphyxiation method. The maxilla of the rats in the test groups were collected and marginal bone loss was observed by micro-CT. The gingival tissues around the implants were collected for further real time quantitative PCR (RT-qPCR) analysis, specifically the expression of tumor necrosis factor-alpha (TNF-α) as well as interleukin-1β (IL-1β). The probing depth (PD), bleeding on probing (BOP) and gingival index (GI) of each rat in the experimental group were recorded before induction of inflammation and before death.@*RESULTS@#After 4 weeks of implantation, the osseointegration of implants were confirmed. All the three test groups showed red and swollen gums, obvious marginal bone loss around implants. After 2 weeks and 4 weeks of inflammation induction, PD, GI and BOP of the three test groups increased compared with those before induction, but only BOP was statistically significant among the three test groups (P < 0.05). At the end of 2 weeks of inflammation induction, marginal bone loss was observed at each site in the cotton thread ligation group and the combined group. At each site, the bone resorption in the combined group was greater than that in the cotton thread ligation group, but the difference was not statistically significant (P > 0.05), bone resorption was observed at some sites of some implants in LPS local injection group. At the end of 4 weeks of inflammation induction, marginal bone loss was observed at all sites in each group. The marginal bone loss in the cotton thread ligation group and the combined group was greater than that in the LPS local injection group, and the difference was statistically significant (P < 0.05). At the end of 2 weeks and 4 weeks of induction, the expression of TNF-α and IL-1β in the test groups were higher than those in the control group (P < 0.05).@*CONCLUSION@#Compared with local injection of LPS around the implant, cotton thread ligature and the two methods combined can induce peri-implantitis in rats better and faster.

Peri-implant bone level assessment of early loaded dental implants submitted to different prosthetic protocols: a case report / Avaliação do nível ósseo peri-implantar de implantes dentários com carregamento antecipado submetidos a protocolos protéticos diferentes: relato de caso

Aim: The present split-mouth case report aims to describe the clinical and radiographic long-term outcomes of the implant rehabilitation of two mandibular premolars in which the digital workflow was used to apply different prosthetic protocols. Case description: A female 42-year-old patient with the absence of both mandibular second premolars was submitted to guided surgery for the placement of platform-switching Grand Morse connection implants. Digital workflow was used for implant and prosthetic planning, applying early loading protocol 21 days after surgery. The implant on the right side received the final abutment at the time of surgery (without loading), whereas the implant on the left side had a healing abutment placed, which was replaced by a temporary abutment and then by a final abutment. Two months after surgery, both implants had final ceramic restorations delivered. The patient was followed clinically and radiographically for 30 months, presenting excellent hard and soft tissue outcomes, with bone level changes lower than 2mm for both implants. Conclusion: The use of digital workflow and early loading, made the present implant-supported rehabilitation predictable, safe and time-efficient, resulting in total patient satisfaction. Peri-implant bone level was observed to be stable after early loading protocol for both platform-switching connection implants inserted, despite the prosthetic protocol applied.(AU)

Objetivo: O presente relato de caso de boca dividida tem como objetivo descrever os resultados clínicos e radiográficos a longo prazo da reabilitação com implante de dois pré-molares inferiores em que o fluxo de trabalho digital foi usado para aplicar os conceitos de "one abutment-one time" em uma das reabilitações e troca de componente no outro. Descrição do caso: Paciente do sexo feminino, 42 anos, com ausência de ambos os segundos pré-molares inferiores, foi submetida à cirurgia guiada para colocação de implantes de conexão Grand Morse plataforma-switching. Foi utilizado fluxo de trabalho digital para planejamento de implante e prótese, aplicando protocolo de carga antecipada 21 dias após a cirurgia. O implante do lado direito recebeu o componente protético definitivo no momento da cirurgia (sem carga), enquanto o implante do lado esquerdo recebeu um cicatrizador, que foi substituído por um pilar provisório e depois por um componente definitivo. Dois meses após a cirurgia, ambos os implantes tiveram restaurações cerâmicas finais entregues. A paciente foi acompanhada clínica e radiograficamente por 30 meses, apresentando excelentes resultados de tecidos duros emoles, com alterações do nível ósseo inferiores a 2mm para ambos os implantes. Conclusão: O fluxo de trabalho digital e carregamento precoce, tornou a presente reabilitação implantossuportada previsível, segura e eficiente em termos de tempo, resultando em total satisfação do paciente. O nível ósseo peri-implantar foi observado como estável após o protocolo de carregamento inicial para ambos os implantes de conexão plataforma-switching inseridos, independente do protocolo protético aplicado. (AU)

Sponges with colloidal silver nanoparticles help restore bone lost in endo-periodontal injuries

Introduction: Endo-periodontal lesions can lead to the formation of severe intraosseous defects in the periodontium; which can lead to tooth loss. Objective: Demonstrate that surgical periodontal therapy with the help of gelatin sponges, with colloidal silver nanoparticles, restores bone tissue lost in endo-periodontal lesions. Case presentation: 55-year-old male patient without systemic alterations, diagnosed with grade 3 endo-periodontal lesion in patients with periodontitis. It was treated first with ducts and then with periodontal surgery combined with gelatin sponges, which contain colloidal silver nanoparticles, and were placed filling the 2-wall bone defect involving > 80 percent of the root length, with 24 months of radiographic and clinical follow-up. Conclusions: Based on the case report, surgical periodontal therapy and filling of bone defects with gelatin sponges, which contain colloidal silver nanoparticles, were sufficient to restore the lost bone at a 24-month follow-up. However, further studies are needed to assess the clinical benefit of this material for the treatment of intraosseous defects(AU)

Vertical bone augmentation with guided bone regeneration: a scoping review / Aumento óseo vertical con regeneración ósea guiada: scoping review

Introduction: There are multiple techniques for vertical bone augmentation. Guided bone regeneration is one of them; however, the literature is diverse and includes different study designs, which makes it difficult to synthesize results. Objective: To analyze the general technical characteristics, clinical results, and complications of vertical bone augmentation performed with guided bone regeneration in humans. Material and Methods: This scoping review was based on the PRISMA-ScR guidelines. A search was performed in the Pubmed, Scielo, and Worldcat databases. Papers published from 1990 to April 2020 were included in the study. Research articles not conducted in humans or published in languages other than English and Spanish were excluded. Title and abstract were screened by two reviewers, then full studies were extracted, and data tabulated. Results: 89 studies were included. The highest percentage reported having obtained a vertical bone increase of less than 5 mm and having used non-resorbable membranes. The most frequent type of graft is autogenous and combinations of grafts, the most common being autogenous with xenograft. All studies that reported bone stability of implants in regenerated bone were favorable, as was implant survival, reporting values between 83.8% and 100%. Membrane exposure is the most frequently reported complication, followed by infection or abscesses, and tissue dehiscence. Conclusion: Vertical bone regeneration is a reliable technique, with high predictability and low incidence of complications compared to other vertical bone augmentation techniques.

Introducción: Existen múltiples técnicas para el aumento óseo vertical siendo una opción la regeneración ósea guiada, sin embargo, la literatura es diversa y con distintos diseños que dificultan la síntesis de resultados. Objetivo: Analizar las características generales técnicas, resultados clínicos y complicaciones del aumento óseo vertical realizado con regeneración ósea guiada en humanos. Material y Métodos: Esta revisión de alcance se basó en la guía PRISMA-ScR. Se realizó una búsqueda en las bases de datos Pubmed, Scielo y Worldcat. Fueron incluidos aquellos publicados desde el año 1990 hasta abril de 2020. Se excluyeron los estudios no realizados en humanos o publicados en idiomas distintos al inglés y español. Dos revisores examinaron título y resumen, luego los estudios completos se extrajeron y se ordenaron los datos en tablas. Resultados: 89 estudios fueron incluidos. El mayor porcentaje reportó haber obtenido un aumento óseo vertical menor a 5 mm y haber utilizado membranas no reabsorbibles. El tipo de injerto que más frecuente es el autógeno y las combinaciones de injertos, siendo el más común autógeno con xenoinjerto. Todos los estudios que reportaron estabilidad ósea de implantes en hueso regenerado fueron favorables, al igual que la supervivencia de implantes, reportando valores entre 83,8% y 100%. La exposición de membrana es la complicación que más se repite en los estudios, seguido por infección o abscesos y dehiscencia de tejidos. Conclusión: La regeneración ósea vertical es una técnica confiable, con alta predictibilidad y baja incidencia de complicaciones en comparación a otras técnicas de aumento óseo vertical.

Cone-beam computed tomographic evaluation of dimensional hard tissue changes following alveolar ridge preservation with leucocyte and platelet-rich fibrin techniques: a pilot study / Avaliação tomográfica computadorizada de feixe cônico das alterações dimensionais de tecido duro após preservação de crista alveolar com técnicas de fibrina rica em leucócitos e plaquetas: um estudo piloto

Objective: This study evaluated the effect of leucocyte and platelet-rich fibrin (L-PRF) techniques used in alveolar ridge preservation on dimensional hard tissue changes of the alveolar ridge assessed using cone-beam computed tomography (CBCT) scans. Material and Methods: Elective alveolar ridge preservation surgeries were performed on seven systemically healthy patients who underwent single posterior tooth extraction. Patients were randomly treated with PRF mixed with a commercial bone xenograft (n = 3) or PRF plug (n = 4). CBCT scans were taken immediately after tooth extraction and then four months later, just before implant surgery. Dimensional alterations in socket height (SH), socket area (SA) and socket volume (SV) were evaluated on CBCT scans by percentage differences before and after treatments. Results: Sockets treated with PRF plus bone xenograft had a tendency to maintain alveolar bone dimensions over time (SH= 11.22% to 82.74%, SA= 1.84% to 48.91% and SV= 9.11% to 203.62%), while sockets treated only with PRF plug technique presented only a modest increase in height (SH= 1.47% to 11.11%) but greater alveolar ridge resorption confirmed by a decrease in socket area and volume dimensions (SA= 0.21% to -24.09% SV= 8.53% to -54.12%). Conclusion: Within the limitations of this study, the maintenance of alveolar socket dimensions was observed when PRF was associated with a xenograft. However, the loss of alveolar ridge dimensions was not entirely prevented by PRF treatment alone.(AU)

Objetivo: Este estudo avaliou o efeito das técnicas de fibrina rica em leucócitos e plaquetas (L-PRF) usadas na preservação da crista alveolar em alterações dimensionais de tecido duro da crista alveolar avaliadas por tomografia computadorizada de feixe cônico (CBCT). Material e Métodos: Foram realizadas cirurgias eletivas de preservação da crista alveolar em sete pacientes sistemicamente saudáveis que foram submetidos a uma única extração dentária posterior. Os doentes foram tratados aleatoriamente com PRF misturado com um xenoenxerto ósseo comercial (n = 3) ou com PRF plug (n = 4). CBCT foi realizada imediatamente após a extração dentária e quatro meses depois, imediatamente antes da cirurgia de implante. Alterações dimensionais na altura do alvéolo (SH), área do alvéolo (SA) e volume do alvéolo (SV) foram avaliadas em exames CBCT por diferenças percentuais antes e depois dos tratamentos. Resultados: Os alvéolos tratados com PRF mais xenoenxerto ósseo apresentaram tendência a manter as dimensões ósseas alveolares ao longo do tempo (SH= 11.22% a 82.74%, SA= 1.84% a 48.91% e SV= 9.11% a 203.62%), enquanto alvéolos tratados apenas com a técnica de PRF plug apresentaram apenas um aumento modesto na altura (SH= 1.47% a 11.11%), mas uma maior reabsorção alveolar confirmada pela redução das dimensões de área e volume do alvéolo (SA= 0.21% a -24.09% SV= 8.53% a -54.12%). Conclusão: Dentro das limitações deste estudo, a manutenção das dimensões alveolares foi observada quando o PRF foi associado ao xenoenxerto. No entanto, a perda das dimensões alveolares não foi totalmente evitada pelo tratamento apenas com PRF. (AU)

Four-Octyl itaconate ameliorates periodontal destruction via Nrf2-dependent antioxidant system / 国际口腔科学杂志·英文版

Periodontitis is a widespread oral disease characterized by continuous inflammation of the periodontal tissue and an irreversible alveolar bone loss, which eventually leads to tooth loss. Four-octyl itaconate (4-OI) is a cell-permeable itaconate derivative and has been recognized as a promising therapeutic target for the treatment of inflammatory diseases. Here, we explored, for the first time, the protective effect of 4-OI on inhibiting periodontal destruction, ameliorating local inflammation, and the underlying mechanism in periodontitis. Here we showed that 4-OI treatment ameliorates inflammation induced by lipopolysaccharide in the periodontal microenvironment. 4-OI can also significantly alleviate inflammation and alveolar bone loss via Nrf2 activation as observed on samples from experimental periodontitis in the C57BL/6 mice. This was further confirmed as silencing Nrf2 blocked the antioxidant effect of 4-OI by downregulating the expression of downstream antioxidant enzymes. Additionally, molecular docking simulation indicated the possible mechanism under Nrf2 activation. Also, in Nrf2-/- mice, 4-OI treatment did not protect against alveolar bone dysfunction due to induced periodontitis, which underlined the importance of the Nrf2 in 4-OI mediated periodontitis treatment. Our results indicated that 4-OI attenuates inflammation and oxidative stress via disassociation of KEAP1-Nrf2 and activation of Nrf2 signaling cascade. Taken together, local administration of 4-OI offers clinical potential to inhibit periodontal destruction, ameliorate local inflammation for more predictable periodontitis.

Clinical classification and treatment decision of implant fracture / 北京大学学报(医学版)

OBJECTIVE@#To propose a set of two-dimensional clinical classification of fractured implants based on the follow-up of fracturing pattern of implant body and peri-implant bone defect morphology of 32 fractrued implants, and summarize the treatment decisions of fractured implants according to this new set of classification, so as to provide guidance for clinical practice.@*METHODS@#During 25 years of clinical practice, clinical records of 27 patients of 32 fractured implants in 5 481 patients with 10 642 implants were made. The fracturing pattern of implant body, implant design, peri-implant bone defect morphology and treatment options were analyzed. A set of two-dimensional clinical classification based on the morphology and bone absorption of implant fracture was proposed. The treatment decision-making scheme based on the new classification of implant fracture was discussed.@*RESULTS@#In the new classification system, vertical fracture of implant neck (Type 1 of implant fracture morphology, F1) and horizontal fracture of implant neck (Type 2 of implant fracture morphology, F2) were common, accounting for 50% and 40.6% respectively, while deep horizontal fracture of implant body (Type 3 of implant fracture morphology, F3) (9.4%) were rare, while the three types of bone defects (D1, no bone defect or narrow infrabony defects; D2, wide 4-wall bone defects or cup-like defects, D3, wide 3-wall or 2-wall defects) around implants were evenly distributed. In the two-dimensional classification system of implant fracture, F1D1 (31.3%) and F2D2 (25%) were the most frequent. There was a significant positive correlation between F1 and D1 (r=0.592, P < 0.001), a significant positive correlation between F2 and D2 (r=0.352, P=0.048), and a significant negative correlation between F1 and D2 (r=-0.465, P=0.007). The most common treatment for implant fracture was implant removal + guided bone regeneration(GBR) + delayed implant (65.6%), followed by implant removal + simultaneous implant (18.8%). F1D1 type was significantly related to the treatment strategy of implant removal + simultaneous implantation (r=0.367, P=0.039). On this basis, the decision tree of implant fracture treatment was summarized.@*CONCLUSION@#The new two-dimensional classification of implant fracture is suitable for clinical application, and can provide guidance and reference for clinical treatment of implant fracture.

Risk analysis and preventive strategies of implant placement in patients with hypertension / 中华口腔医学杂志

Recently, among the edentulous patients who undergo dental implants, the proportion of hypertensive patients remains high, which poses a greater challenge for clinicians to operate and to maintain the therapeutic effect. The present review comprehensively summarized clinical researches about the adverse effects on dental implants, outlined molecular mechanisms of the positive effects of various antihypertensive drugs on bone metabolism, and proposed that clinicians should select preventive strategies during preoperative and intraoperative procedures according to the blood pressure of patients with hypertension.

Efectos de la administración local de PTH 1-34 a bajas dosis en un modelo experimental de periodontitis: estudio piloto / Local effects of low dose of PTH 1-34 on experimental periodontitis: pilot study

La periodontitis es una patología inflamatoria que aumenta la resorción de hueso alveolar (HA), pérdida de la inserción dentaria y posible exfoliación. Evaluamos el efecto de la administración intermitente de bajas dosis de parathormona (PTH) 1-34 sobre la recuperación de la masa ósea pérdida en un modelo experimental de periodontitis inducida por una ligadura periodontal (LP) con hilo de algodón alrededor de la pieza dentaria. Las ratas fueron divididas luego de 5 días en instaurada la periodontitis en: CT LP sin trata-miento y PTH LP tratados con 0,2 µg/kg PTH 1-34 subcutánea local, tres veces por semana por 17 días. El control absoluto fue un tercer grupo sin LP (CT). Se estudiaron parámetros antropométricos, bioquímicos e histomosfométricos en tibias y hemimandibulas. La calcemia, fosfatemia, CTX sérico, PTHi y vo-lumen óseo (BV/TV%) de tibias fueron similares en los tres grupos. El BV/TV% del HA fue significativamente menor en PTH LP respecto de CT pero mayor que CT LP (p<0.05). La pérdida ósea de HA porcentual fue significativamente mayor en CT LP (p<0.05). La altura del ligamento periodontal fue significativamente menor en PTH LP que en CT (p<0.05) y mayor respecto de CT LP, sin alcanzar diferencias significativas. Los resultados del presente estudio piloto sugieren que la administración intermitente de PTH en bajas dosis y durante un periodo de tiempo corto disminuye la progresión de la enfermedad periodontal sin generar efectos sistémicos. Como no se logró regenerar totalmente el tejido periodontal se requieren estudios adicionales. (AU)

Periodontitis is an inflammatory chronic disease with high prevalence in adults that induces a progressive alveolar bone (AB) loss leading to tooth loss. Experimental periodontitis can be induced in rats by cotton ligature placement (LP) in the gingival sulcus around the molar teeth. The biofilm accumulation and disruption of the gingival epithelium lead to bone resorption. We investigated whether intermittent administration of a low dose of PTH 1-34 may recover the alveolar bone loss in the experimental periodontitis induced in female Wistar rats. Animals were randomly divided in two groups which were subcutaneously injected with: saline solution (CT LP) or 0,2 µg/kg PTH 1-34 (PTH LP) three times per week during 17 days. Unligated rats were taken as healthy controls (CT). Anthropometric, biochemical and histologic analysis of tibia and hemimandible were done. No differences in serum calcium, phosphorus, CTX, PTHi or subchondral tibia bone volume (BV/TV%) were observed between the three groups. AB BV/TV% was significantly lower in PTH LP than in CT but higher than in CT LP (p<0.05). The highest percentage of AB loss was observed in CT LP. The height of periodontal ligament was lower in PTH LP than in CT (p<0.05) but not significantly higher than CT LP.The increase in AB loss by experimental periodontitis appears to be corrected by the intermittent administration of low doses of PTH without systemic effect. As the recovery of periodontal tissue was only partial, additional studies should be done.

Avaliação da perda óssea utilizando diferentes parâmetros na análise microtomográfica: estudo em ratos / Bone loss assessment using different parameters in the microtomographic analysis: study in rats

Introdução: o desafio no uso do Micro-Ct tem sido estabelecer e padronizar padrões adequados para escaneamento e tratamento das imagens, para que se obtenha o máximo desempenho do equipamento, e permitir a comparação dos achados entre diferentes estudos. Objetivo: o presente estudo tem como objetivo comparar a porcentagem de volume ósseo em regiões com perda óssea periodontal utilizando diferentes metodologias para definição da área a ser analisada (ROI). Material e método: dez ratos foram submetidos à indução de doença periodontal, e, após a eutanásia, as mandíbulas foram escaneadas com cortes de 9 µ e 18 µm de espessura, com passo de rotação de 0.3mm. As imagens foram reconstituídas utilizando o software NRecon, e em seguida, utilizando o software CTAnalyser - CTAn, foram definidas as áreas de interesse (ROI) ao redor dos segundos molares. A primeira área de interesse (ROI1) foi definida em um padrão retangular que se restringiu às regiões interproximais e furca, onde a área total de tecido ósseo foi obtida somando os resultados dos 3 ROIs. A segunda área (ROI2) foi definida no sentido corono/apical ao redor do segundo molar até suas limitações proximais com os dentes vizinhos, onde a porcentagem de tecido ósseo pertencente às raízes foram excluídas das avaliações. As análises foram realizadas com cinco diferentes valores de thresholds (130-50, 130-60, 130-70, 130-80, 130-90 e 130-100). Resultado: a análise entre os diferentes ROIs demonstrou que em ambas as análises foi observada a tendência a menor porcentagem de tecido ósseo quanto maior o contraste de tons de cinza utilizado, no entanto, nos resultados obtidos no ROI2 essa diferença não foi estatisticamente significante. Conclusão: com os resultados obtidos pode se concluir que a utilização de diferentes thresholds para quantificação óssea, em áreas onde houve doença periodontal, pode trazer resultados divergentes; a definição da área de interesse interfere com os resultados obtidos e que a obtenção de uma área de interesse com a remoção das raízes mostrou-se menos susceptível à variação dos parâmetros de escaneamento.

Introduction: the challenge in the use of Micro-Ct has been to establish and standardize adequate standards for scanning and image processing to obtain the maximum performance of the equipment and to allow the comparison of findings between different studies. Objective: this study aims to compare the percentage of bone volume in regions with periodontal bone loss using different methodologies to define the area to be analysed (ROI). Material and method: ten rats were submitted to periodontal disease induction, and, after euthanasia, the mandibles were scanned with slices of 9µ and 18 µm thickness, with a rotation step of 0.3mm. The images were reconstructed using the NRecon software, and then, using the CTAnalyser - CTAn software, the areas of interest (ROI) around the second molars were defined. The first area of interest (ROI1) was defined in a rectangular pattern that was restricted to the interproximal and furcation regions, where the total area of bone tissue was obtained by adding the results of the 3 ROIs. The second area (ROI2) was defined in the coronal/apical direction around the second molar to its proximal limitations with the neighboring teeth, in which the percentage of bone tissue belonging to the roots was excluded from the evaluations. Analyses were performed with five different threshold values (130-50, 130-60, 130-70, 130-80, 130-90, and 130-100). Result: the analysis between the different ROIs showed that, in both analyses, there was a tendency towards a lower percentage of bone tissue the greater the grayscale contrast used. However, in the results obtained in ROI2, this difference was not statistically significant. Conclusion: with the results obtained, it can be concluded that the use of different thresholds for bone quantification, in areas where there was a periodontal disease, can bring divergent results; the definition of the area of ​​interest interferes with the results obtained; and that obtaining an area of interest with the removal of the roots, proved to be less susceptible to the variation of the scanning parameters.

Elevación unilateral de piso de seno maxilar con ventana lateral utilizando xenoinjerto: reporte de caso / Unilateral elevation of maxillary sinus floor with lateral window using xenografts: report of a case

En maxilares atróficos la elevación de piso de seno es una práctica de alta predictibilidad. El adve- nimiento de materiales osteoconductores que generan andamiaje para la formación ósea propor- cionaron un aumento en la tasa de éxito de los implantes endoóseos. El presente artículo reporta un caso clínico en el cual se llevo a cabo un aumento del nivel de altura del piso de seno unila- teralmente por medio de la técnica de Cadwell- Luck modificada por Tatum, técnica con ventana lateral, donde se utilizó xenoinjerto óseo (OstiumMAX, implante de matriz ósea bovina, Laboratorio Bioxen) y membrana reabsorbible de colágeno( Laboratorio Bioxen) en el primer tiempo quirúrgi- co y seis meses después, en el segundo acto quirúrgico se colocaron tres implantes endoóseos (Sistema de implante dental TRP, Laboratorio Tormicron S.R.L.). Los resultados obtenidos fueron controlados en forma mediata y a distancia a través de radiografías panorámicas y tomografías computadas tipo Cone Beam, donde se midió la altura ósea generada post injerto. Pudo consta- tarse el éxito del procedimiento, basándonos en criterios clínico radiograficos de oseointegración (AU)

Esthetic patient satisfaction, marginal bone loss and peri-implant tissue success in esthetic zone: systematic review / Satisfação estética do paciente, perda óssea marginal e sucesso do tecido peri-implantar na zona estética: revisão sistemática

Increased patient demands for highly esthetic implant superstructure in the anterior esthetic zone has increased in the last decades. Moreover, the absence of periodontal ligament in implant supported prosthesis causes forces to be transferred without cushioning effect to the alveolar bone, resulting in increased marginal bone loss (MBL) and influence the heath of peri-implant tissue. Evaluate the available evidence on the effect implant superstructure and it consequences on patient satisfaction, MBL, bleeding on probing (BOP) and probing depth (PD). A protocol of electronic and hand research was performed for English based researches comparing implants inserted in the esthetic zone with all ceramic superstructure: "Will the use of different types of all ceramic superstructure show different esthetic patient satisfaction, marginal bone loss, bleeding on probing and probing depth? Thirteen publications from one thousand one hundred and sixteen research studies were included. This systematic review showed that all ceramic implant superstructure was a versatile treatment option with higher esthetic patient satisfaction and better color of peri-implant mucous especially in patients having thin biotype. On the other hand there wasn't significant difference in MBL, PD and BOP compared to other conventional implant superstructure. More randomized controlled clinical trials with bigger samples are needed to confirm our findings. All ceramic implant superstructure is versatile and highly esthetic treatment option for implant placed in the anterior esthetic zone.(AU)

A demanda do paciente por superestruturas de implante altamente estéticas na zona anterior aumentou nas últimas décadas. Além disso, a ausência de ligamento periodontal em próteses implantossuportadas faz com que as forças sejam transferidas para o osso alveolar sem amortecimento, resultando em aumento da perda óssea marginal (MBL) e influenciando na saúde do tecido peri-implantar. Avaliar as evidências disponíveis sobre o efeito da superestrutura do implante e suas consequências na satisfação do paciente, perda óssea marginal, sangramento à sondagem (SS) e profundidade de sondagem (PS). Um protocolo de pesquisa eletrônica e manual foi realizado para a análise de artigos em inglês comparando implantes com toda a superestrutura em cerâmica inseridos na zona estética: "O uso de diferentes tipos de superestrutura em cerâmica mostrará diferentes níveis de satisfação estética do paciente, perda óssea marginal, sangramento em profundidade de sondagem e sondagem?". Foram selecionadas 1116 publicações e apenas treze estudos foram incluídos na análise final. Esta revisão sistemática mostrou que toda superestrutura do implante em cerâmica foi uma opção de tratamento versátil, com maior satisfação estética do paciente e melhor coloração da mucosa peri-implantar, especialmente em pacientes com biótipo fino. Por outro lado, não houve diferença significativa em MBL, PS e SS em comparação com outras superestruturas de implantes convencionais. Porém, mais ensaios clínicos controlados randomizados com amostras maiores são necessários para confirmar nossos achados. Implicações clínicas: Toda superestrutura do implante em cerâmica é uma opção de tratamento versátil e altamente estética para implantes colocados na zona anterior (AU)