Etiopatogenia e tratamento da osteonecrose dos maxilares induzida por medicamentos: aspectos essenciais ao dentista / Etiopathogenesis and treatment of medication-related osteonecrosis of the jaw: essential aspects for the dentist

A osteonecrose dos maxilares induzida por medicamentos (MRONJ) caracteriza-se por exposição óssea ou osso que pode ser sondado através de fístula intra ou extraoral, em região maxilofacial, e que não cicatriza dentro de oito semanas. A MRONJ é uma condição rara e debilitante que pode causar dor, disfagia e odor desagradável na cavidade oral, afetando pacientes com histórico ou sob uso contínuo de terapia antirreabsortiva, isolada ou associada a imunomoduladores ou drogas antiangiogênicas, mas sem histórico de radioterapia nos maxilares. O objetivo desta revisão narrativa de literatura é compilar os principais aspectos sobre a etiopatogenia da MRONJ e as opções terapêuticas disponíveis. A etiologia da MRONJ é multifatorial, complexa, e não está totalmente compreendida, não havendo um tratamento definitivo, mas diversas modalidades terapêuticas que visam o controle da dor e da progressão da osteonecrose. Conclui-se com essa revisão que o entendimento da etiopatogenia da MRONJ pelo cirurgião-dentista lhe permite adotar medidas preventivas, bem como o conhecimento das modalidades terapêuticas disponíveis lhe possibilita oferecer o manejo adequado para seu paciente, conforme o estágio da doença.

Medication-related osteonecrosis of the jaw (MRONJ) is characterized by exposed bone or bone that can be probed through an intra or extraoral fistula, in the maxillofacial region, which does not heal within eight weeks. MRONJ is a rare and debilitating condition that can cause pain, dysphagia and unpleasant odor in the oral cavity, affecting patients with a history or continuous use of antiresorptive therapy, alone or associated with immunomodulators or antiangiogenic drugs, but without a history of radiotherapy to the jaws. The aim of this narrative literature review is to compile the main aspects about the etiopathogenesis of MRONJ and the available therapeutic options. The etiology of MRONJ is multifactorial, complex, and is not fully understood, with no definitive treatment, but several therapeutic modalities that aim to control pain and the progression of osteonecrosis. It is concluded from this review that the understanding of the etiopathogenesis of MRONJ by the dental surgeon allows him to adopt preventive measures, as well as the knowledge of the therapeutic modalities available allows him to offer the appropriate management for his patient, depending on the stage of the disease.

Osteomielitis crónica mandibular. Informe de dos casos clínicos / Chronic mandibular osteomyelitis. A report of two clinical cases

Objetivo: Presentar dos casos clínicos inusuales de osteomielitis crónica en mandíbula, su resolución quirúrgica y destacar los aspectos clínicos, radiológicos e histológicos más relevantes. Casos clínicos: Se reportaron dos casos clínicos de pacientes con osteomielitis crónica en mandíbula que acudieron al Servicio de Odontología del Hospital Interzonal General de Agudos "Eva Perón". El primero fue un raro caso de osteomielitis ubicada de forma aislada en el cóndilo mandibular izquierdo. El tratamiento consistió en la resección quirúrgica del cóndilo mandibular afectado, seguido de terapia antibiótica a largo plazo. El segundo caso clínico se trató de un paciente con pericoronaritis asociado a un tercer molar inferior impactado. El tratamiento se basó en el desbridamiento quirúrgico más la colocación de drenaje, seguido de terapia antibiótica. En ambos pacientes el diagnóstico de osteomielitis se confirmó mediante el estudio histológico de las muestras quirúrgicas, y tras seguimiento de 24 y 12 meses para el caso 1 y 2 respectivamente, no se han reportado recurrencias de la patología.(AU)

Aim: To present two unusual cases of chronic mandibular osteomyelitis, its surgical resolution and highlight the most relevant clinical, radiological and histological aspects. Clinical cases: Two clinical cases of patients with chronic mandibular osteomyelitis who attended the Dentistry Service of the "Eva Perón" Interzonal General Acute Hospital were reported. The first was a rare case of osteomyelitis located isolated in the left mandibular condyle. Treatment consisted of surgical resection of the affected mandibular condyle, followed by long-term antibiotic therapy. The second clinical case was a patient with pericoronitis associated with an impacted lower third molar. Treatment was based on surgical debridement and drain placement, followed by antibiotic therapy. In both patients the diagnosis of osteomyelitis was confirmed by histological study of the surgical samples, and after follow-up of 24 and 12 months for cases 1 and 2 respectively, no recurrences of the pathology have been reported.(AU)

Effectiveness of leukocyte- and platelet-rich fibrin in the management of medication-related osteonecrosis of the jaws ­ a systematic review / Efectividad de la fibrina rica en leucocitos y plaquetas en el tratamiento de osteonecrosis mandibular relacionada con medicamentos: una revisión sistemática

Background: Medication-related osteonecrosis of the jaw (MRONJ) is a rare, but significant adverse event primarily associated with the intake of antiresorptive and antiangiogenic medications. Although antiresorptive and antiangiogenic the-rapies improve life expectancy, particularly in cancer patients, MRONJ may hamper the patient's quality of life due to pain, discomfort, anxiety, depression, speech impairment, difficulty in swallowing and eating, frequent medical and dental evaluations and treatments, and the possibility of treatment discontinuation. Leukocyte­ and Platelet-rich Fibrin (L-PRF) is an autologous platelet aggregate that promotes wound healing by stimulating re-epithelialization, angiogenesis, and extracellular matrix production. Aim: The present systematic review aimed to compare the results in the published literature on whether L-PRF is an effective and predictable adjuvant to surgical debridement of necrotic bone for improving the healing efficacy in patients with MRONJ. Materials and Methods: The PubMed, Scopus, Cochrane, Science Direct, LILACS, and Web of Science databases were searched using the predetermined MeSH terms and eligibility criteria, and the search yielded a total of five articles. Two studies were retrospective, and three studies were case series. Results: Seventeen participants received a combination of surgical debridement, L-PRF membrane, and antibiotics. Complete wound healing was observed in 70% of the participants, and most of them healed without any complications. Conclusions: L-PRF as an adjuvant to surgical debridement of necrosed bone appears to have a positive association with the healing outcome in patients with MRONJ.

Introducción: La osteonecrosis mandibular relacionada con medicamentos (ONMRM) es un evento adverso raro pero significativo asociado principalmente con la ingesta de medicamentos antirresortivos y antiangiogénicos. Aunque las terapias antirresortivas y antiangiogénicas mejoran la esperanza de vida, particularmente en pacientes con cáncer, la ONMRM puede obstaculizar la calidad de vida del paciente debido a dolor, incomodidad, ansiedad, depresión, discapacidad del habla, dificultad para tragar y comer, evaluaciones y tratamientos médicos y dentales frecuentes, y la posibilidad de interrupción del tratamiento. La fibrina rica en plaquetas y leucocitos (L-PRF) es un agregado de plaquetas autólogo que promueve la curación de heridas al estimular la reepitelización, la angiogénesis y la producción de la matriz extracelular. Objetivo: La presente revisión sistemática tuvo como objetivo comparar los resultados en la literatura publicada sobre si L-PRF es un adyuvante efectivo y predecible al desbridamiento quirúrgico del hueso necrótico para mejorar la eficacia curativa en pacientes con ONMRM. Materiales y Métodos: Las bases de datos de PubMed, Scopus, Cochrane, ScienceDirect, LILACS y Web of Science se registraron utilizando los términos DeCS/MeSH predeterminados y los criterios de elegibilidad, y la búsqueda arrojó un total de cinco artículos. Dos estudios fueron retrospectivos, y tres estudios fueron series de casos. Resultado: Diecisiete participantes recibieron una combinación de desbridamiento quirúrgico, membrana L-PRF y antibióticos. Se observó curación completa de heridas en el 70% de los participantes, y la mayoría de ellos se curaron sin ninguna complicación. Conclusión: L-PRF como adyuvante para el desbridamiento quirúrgico del hueso necrótico parece tener una asociación positiva con el resultado de curación en pacientes con ONMRM.

Beneficios de la descompresión y enucleación en lesiones quísticas de gran tamaño en la mandíbula / Benefits of decompression and enuclation in large cystic lesions in the jaw / Benefícios da descompressão e enuclação nas grandes lesões císticas na mandíbula

Las lesiones quísticas ocurren en los maxilares, por la presencia de células remanentes del neuroectodermo embrionario. La descompresión es una técnica conservadora para disminuir la presión intraquística mediante drenaje constante, permitiendo el crecimiento de nuevo hueso centrípeto de las paredes óseas del quiste. Objetivo: determinar los beneficios de la descompresión y enucleación en lesiones quísticas mandibulares, tomando como base la metodología de un caso clínico. Descripción del caso: se diagnosticó una lesión quística mandibular en paciente masculino de 27 años, que acudió a consulta mostrando secreción purulenta en mucosa trígono retromolar de UD 37, inicialmente asintomática. Se utilizaron como materiales la tomográfica computarizada de haz cónico, artefacto de drenaje autocurado, hemiarcada izquierda elaborada con Metil Metacrilato y aparato a base de cilindro. Como resultados se reveló imagen hipodensa de bordes definidos localizada en el límite posterior de cuerpo mandibular, borde anterior y parte de la rama ascendente mandibular del lado izquierdo; extendida en sentido cefálico caudal desde la cresta alveolar y borde anterior de la rama hasta la cortical superior del conducto mandibular. Conclusión: Se confirmó diagnóstico de quiste periapical, quiste residual y ameloblastoma. Se realizó biopsia incisional de la lesión para estudio histopatológico y la descompresión con dispositivo personalizado a enucleación conminada con solución de Carnoy, resultando el tratamiento conservador efectivo complementado por la enucleación de una membrana quística más gruesa y menos friable.

Cystic lesions occur in the jaws due to the presence of remnant cells of the embryonic neuroectoderm. Decompression is a conservative technique to decrease intracystic pressure by constant drainage, allowing the growth of new centripetal bone from the bony walls of the cyst. Objective: to determine the benefits of decompression and enucleation in mandibular cystic lesions, based on the methodology of a clinical case. Case description: a cystic mandibular lesion was diagnosed in a 27 year old male patient, who came for consultation showing purulent secretion in the trigone retromolar mucosa of UD 37, initially asymptomatic. The materials used were cone beam computed tomography, self-curing drainage device, left hemiarch made with Methyl Methacrylate and cylinder based apparatus. The results revealed a hypodense image with defined borders located in the posterior limit of the mandibular body, anterior border and part of the ascending mandibular branch on the left side; extended in a caudal cephalic direction from the alveolar crest and anterior border of the branch to the superior cortical of the mandibular duct. Conclusion: Diagnosis of periapical cyst, residual cyst and ameloblastoma was confirmed. An incisional biopsy of the lesion was performed for histopathological study and decompression with a customized device to enucleation with Carnoy's solution, resulting in effective conservative treatment complemented by enucleation of a thicker and less friable cystic membrane.

As lesões císticas ocorrem nos maxilares, devido à presença de células remanescentes da neuroectoderme embrionária. A descompressão é uma técnica conservadora que visa reduzir a pressão intracística por meio de drenagem constante, permitindo o crescimento de novo osso centrípeto a partir das paredes ósseas do cisto. Objetivo: determinar os benefícios da descompressão e da enucleação em lesões císticas mandibulares, com base na metodologia de um caso clínico. Descrição do caso: foi diagnosticada uma lesão cística mandibular em um paciente do sexo masculino, 27 anos, que se apresentou para consulta apresentando secreção purulenta na mucosa do trígono retromolar do UD 37, inicialmente assintomática. Os materiais utilizados foram tomografia computadorizada de feixe cônico, dispositivo de drenagem autopolimerizável, hemiarco esquerdo confeccionado com metacrilato de metila e aparelho de base cilíndrica. Os resultados revelaram uma imagem hipodensa com limites definidos localizada no limite posterior do corpo mandibular, bordo anterior e parte do ramo mandibular ascendente do lado esquerdo; estendendo-se em direção cefálica caudal desde a crista alveolar e bordo anterior do ramo até ao córtex superior do ducto mandibular. Conclusão: Foi confirmado o diagnóstico de quisto periapical, quisto residual e ameloblastoma. Foi efectuada uma biopsia incisional da lesão para estudo histopatológico e descompressão com um dispositivo adaptado à enucleação cominutiva da solução de Carnoy, resultando num tratamento conservador eficaz complementado pela enucleação de uma membrana quística mais espessa e menos friável.

Tumor odontogénico adenomatoide. Reporte de un caso clínico / Adenomatoid odontogenic tumor. Clinical case report

El Tumor Odontogénico Adenomatoide (TOA) es una neoplasia benigna poco común, caracterizada por un crecimiento lento y progresivo, en la mayoría de los casos asintomático. Es una patología intraósea, que puede ser folicular o extrafolicular, siendo el tipo folicular el más común. Se presenta en hombres y mujeres, con predilección por el sexo femenino. Histológicamente está compuesto por epitelio odontogénico organizado en distintos patrones histoarquitectónicos, incrustado en un estroma de tejido fibroconectivo maduro. Se describe el caso clínico de una paciente femenina de 25 años, con aumento de volumen en la región maxilar anterior izquierda, que se extiende a la base de la nariz, produce desvío de la línea media a la derecha y tiene un año de evolución.

The Adenomatoid Odontogenic Tumor (AOT) is an uncommon benign neoplasm, characterized by slow and progressive growth, in most cases asymptomatic. It is an intraosseous pathology, which can be follicular or extrafollicular, with the follicular type being the most common. It occurs in both men and women, with a predilection for the female sex. Histologically, it is composed of odontogenic epithelium organized in different histoarchitectonic patterns, embedded in a stroma of mature fibroconnective tissue. We describe the clinical case of a 25-year-old female patient with increased volume in the left anterior maxillary region, extending to the base of the nose, causing deviation of the midline to the right and having one year of evolution.

Injertos Óseos en Quistes de los Maxilares. Reporte de un Caso

Los quistes de los maxilares son las lesiones óseas más comunes en la región maxilofacial. La enucleación de las lesiones y el cierre primario de los defectos, son en conjunto, el tratamiento óptimo hoy en día. En algunas ocasiones el defecto óseo resultante puede ser de un tamaño tan grande que afecta la estabilidad de dientes vecinos, comprometa la indemnidad del hueso o produce un retraso cicatrizal que incluso puede impedir una regeneración ósea completa. Se considera que esta falta de regeneración expone al paciente a riesgos de infección tardía, retraso de los tratamientos rehabilitadores en zonas de alta demanda estética y pérdida de vitalidad dentaria. Para disminuir el riesgo de alteraciones en la regeneración ósea completa de cavidades quísticas, se ha propuesto la posibilidad de que tras la enucleación del quiste se rellenen estos defectos con injertos óseos u otras técnicas de preservación alveolar para favorecer la cicatrización. Teóricamente el uso de estos injertos mejora la calidad y disminuye el tiempo de cicatrización ósea, permitiendo que el paciente recupere rápidamente las funciones habituales del componente dentoalveolar, acortando el periodo de cuidados postoperatorios que restringen la alimentación, los deportes o la rehabilitación oral. El actual trabajo tiene como objetivo realizar una revisión de la literatura respecto a los beneficios del uso de injertos óseos en el tratamiento quirúrgico de los quistes maxilares y presentar un caso clínico con los detalles quirúrgicos de esta técnica.

Jaw cysts are the most common bone lesions in the maxillofacial region. Enucleation of the lesions along with the primary closure of the defects are the optimal treatment nowadays. On some occasions, the resulting bone defect can be so large that it affects the stability of neighboring teeth, compromises the integrity of the bone, or produces a delayed healing that can even prevent complete bone regeneration. It is considered that the lack of regeneration exposes the patient to risk of infection, delay of rehabilitation treatments in areas of high aesthetic demand and loss of dental vitality. To reduce the risk of alterations in complete bone regeneration of cystic cavities, the possibility of filling these defects with bone grafts or other alveolar preservation techniques to promote healing, has been proposed after cyst enucleation. Theoretically, the use of these grafts improves the quality and decreases the bone healing time, allowing the patient to quickly recover the usual functions of the dentoalveolar component, limiting the period of postoperative care that restricts eating, sports or oral rehabilitation. The present work aims to carry out a review of the literature regarding the benefits of the use of bone grafts in the surgical treatment of maxillary cysts and to present a clinical case with the surgical details of this technique.

Glandular Odontogenic Cyst: A Case Report and Literature Review

The glandular odontogenic cyst (GOC) is a pathological entity that most commonly develops in the anterior region of the mandible and can emulate other lesions, including other cysts, odontogenic tumors, and even malignant lesions of glandular origin. Therefore, the aim of this manuscript is to report a new case of GOC treated conservatively and to discuss its clinical, radiological, histopathological, and therapeutic aspects.

El quiste odontogénico glandular (QOG) es una entidad patológica que se desarrolla con mayor frecuencia en la región anterior de la mandíbula y que puede mimetizar otras lesiones incluyendo otros quistes, tumores odontogénicos y hasta lesiones malignas de origen glandular. Por lo tanto, el objetivo del presente manuscrito es reportar un nuevo caso de QOG tratado de forma conservadora y discutir sus aspectos clínicos, imagenológicos, anatomopatológicos y terapéuticos.

O trauma de face submetido a cirurgia: Uma análise epidemiológica de 10 anos no interior do Brasil / Facial trauma undergoing surgery: A 10-year epidemiological analysis in the interior of Brazil

Introdução: O trauma de face representa significativa incapacitação para a vítima, além de um desafio para as equipes de saúde devido a sua complexidade e envolvimento de estruturas nobres. Analisar a sua epidemiologia permite coordenar medidas em saúde pública para melhorar o atendimento e a prevenção. Método: Estudo observacional, descritivo, longitudinal, com abordagem retrospectiva a partir dos prontuários dos pacientes vítimas de trauma de face atendidos pela clínica cirúrgica no período entre 2010 e 2019. Resultados: Dentre os 529 prontuários incluídos no estudo e analisados, 71,08% tratava-se de cirurgias eletivas e o restante, 28,92%, de cirurgias de urgência. O trauma foi mais frequente em indivíduos de 20 a 29 anos, o que corresponde a 31,76% do total de casos. Também foi mais frequente em indivíduos do sexo masculino, correspondendo a 78,45% do total de casos. Acidentes automobilísticos foram a causa mais comum, descrita em 22,31% dos prontuários, e a principal fratura, presente em 85,83% dos casos, foi dos ossos próprios do nariz. Conclusão: As vítimas de traumatismo bucomaxilofacial atendidas no Hospital de Clínicas da Universidade Federal do Triângulo Mineiro são predominantemente homens na terceira década de vida, envolvidos em acidentes automobilísticos, com lesões em ossos do nariz que foram abordadas de forma eletiva.

Introduction: Facial trauma represents significant incapacitation for the victim, as well as a challenge for healthcare teams due to its complexity and involvement of important structures. Analyzing its epidemiology allows us to coordinate public health measures to improve care and prevention. Method: Observational, descriptive, longitudinal study with a retrospective approach based on the medical records of patients who suffered facial trauma treated by the surgical clinic between 2010 and 2019. Results: Among in individuals aged 20 to 29 years, which corresponds to 31.76% of total cases. It was also more common in males, corresponding to 78.45% of total cases. Car accidents were the most common cause, described in 22.31% of medical records, and the main fracture, present in 85.83% of cases, was of the bones of the nose. Conclusion: Victims of oral and maxillofacial trauma treated at the Hospital de Clínicas da Universidade Federal do Triângulo Mineiro are predominantly men in their third decade of life, involved in automobile accidents, with injuries to the bones of the nose that were treated electively.

Periodontal status and mandibular biomechanics in rats subjected to hyposalivation and periodontitis / Estudio del estado periodontal y la biomecánica mandibular en ratas sometidas a hiposalivación y periodontitis

ABSTRACT Xerostomia emerges as a consequence of salivary gland hypofunction, and seriously compromises the integrity of hard and soft oral tissues, whileperiodontitis is an infectious disease characterized by biofilm accumulation, inflammation and alveolar bone resorption. Aim The aim this study was to compare the deleterious effects caused by experimental hyposalivation, periodontitis, and the combination of both on periodontal tissues and mandibular biomechanics in rats. Materials and Method Hyposalivation (group H) was induced through bilateral submandibulectomy. Periodontitis (group EP) was induced by injecting LPS (1 mg/ml) into the gingiva of the first lower molars. A third group was subjected to both conditions (group H+EP). Alveolar bone loss was evaluated by micro-computed tomography and histomorphometric analysis, and gingival inflammatory mediators were assessed by specific techniques. Biomechanical properties were evaluated in mandible. Results Alveolar bone loss increased similarly in groups H, EP and H+EP compared to control. Metalloproteinase (MMP2 and MMP9) activity was similar in H and control, but higher in groups EP and H+EP (MMP2: C 9644+2214, EP 34441+3336, H 5818+1532, H+EP 42673+3184; MMP9: C 5792+961, EP 14807+861, H 9295+520, H+EP 4838+1531). The rest of the inflammatory mediators evaluated increased in groups H, EP and H+EP to a greater or lesser extent with respect to the control, although in most cases, they were higher in groups EP and H+EP than in group H. The biomechanical properties of the mandible increased in group H compared to the other three groups. Conclusions Both hyposalivation and periodontitis cause periodontal damage, but hyposalivation also produces biomechanical alterations, causing more extensive deleterious effects than periodontitis.

RESUMEN La xerostomía surge como consecuencia de la hipofunción de las glándulas salivales y compromete seriamente la integridad de los tejidos orales duros y blandos, mientras que la periodontitis es una enfermedad infecciosa caracterizada por la acumulación de biofilm, inflamación y reabsorción ósea alveolar. Objetivo El objetivo del presente estudio fue comparar los efectos deletéreos causados por la hiposalivación y la periodontitis experimental, y la combinación de ambas sobre los tejidos periodontales y la biomecánica mandibular en ratas. Materiales y Método La hiposalivación (H) se indujo mediante una submandibulectomía bilateral. Por otra parte, la periodontitis (PE) se indujo mediante la inyección de LPS (1 mg/ml) en la encía de los primeros molares inferiores. Otro grupo se sometió a ambas condiciones (H+PE). La pérdida ósea alveolar se evaluó mediante tomografia microcomputarizada y análisis histomorfométrico, mientras que los mediadores inflamatorios gingivales fueron determinados mediante técnicas específicas. Se evaluaron las propiedades biomecánicas en la mandíbula. Resultados La hiposalivación aumentó la pérdida ósea alveolar en comparación con el control de forma similar a la PE y H+PE. La actividad de las metaloproteinasas (MMP2 y MMP9) fue similar en los grupos H y control, pero resultó mayor en los grupos PE y H+PE (MMP2: C 9644+2214, PE 34441+3336, H 5818+1532, H+PE 42673+3184; MMP9: C 5792+961, PE 14807+861, H 9295+520, H+PE 24838+1531). El resto de los mediadores inflamatorios evaluados aumentaron en mayor o menor medida en los grupos H, PE y H+PE respecto al control, aunque en la mayoría de los casos fueron superiores en los grupos PE y H+PE respecto al grupo H. Sin embargo, las propiedades biomecánicas de la mandíbula aumentaron en el grupo H con respecto a los otros grupos. Conclusiones Tanto la hiposalivación como la periodontitis causan daño periodontal, pero la hiposalivación también produce alteraciones biomecánicas, provocando efectos deletéreos más extensos que la periodontitis.

Histopathological characteristics of peri-implant soft tissue in reconstructed jaws with vascularized bone flaps / 北京大学学报(医学版)

Objective:To analyze the histopathological characteristics of peri-implant soft tissue in re-constructed jaws and the changes after keratinized mucosa augmentation(KM A)with free gingival graft(FGG).Methods:Twenty patients were enrolled in this study.Five patients of them,who were perio-dontal and systemic healthy and referred for crown lengthening before restoration with healthy keratinized gingiva collected were enrolled as healthy controls.15 patients of them were with fibula or iliac bone flaps jaw reconstruction(10 with fibula flap and 5 with iliac flap),who were referred to FGG and implant exposures before restoration.Soft tissue was collected before FGG in reconstructed jaws,and in 5 patients(3 with fibula flap and 2 with iliac flap)8 weeks after FGG if a second surgery was conducted.Histologi-cal analysis with hematoxylin-eosin stain and immunological analysis to interlukin-1(IL-1),interlukin-6(IL-6)and tumor necrosis factor-α(TNF-α)were performed.Results:Thickness from the bottom of stratum basale to the top of stratum granulosum and thickness of keratinized layer in reconstructed jaws were significantly lower compared with that of natural healthy keratinized gingiva[0.27(0.20,0.30)mmvs.0.36(0.35,0.47)mm,P＜0.05;16.49(14.90,23.37)μm vs.26.37(24.12,31.53)μm,P＜0.05].In the reconstructed area,thickness from the bottom of stratum basale to the top of stra-tum granulosum increased after KMA with FGG[0.19(0.16,0.25)mm vs.0.38(0.25,0.39)mm,P=0.059]and the thickness of keratinized layer significantly increased after KMA with FGG[16.42(14.16,22.35)μm vs.28.57(27.16,29.14)μm,P＜0.05],which was similar to that in the con-trol group.Furthermore,the number of positive cells of IL-1,IL-6 and TNF-α significantly increased after KMA[0.67(0.17,8.93)vs.11.00(9.16,18.00);13.00(8.50,14.14)vs.21.89(15.00,28.12);0.22(0.04,0.63)vs.2.83(1.68,5.00),respectively,P＜0.05]as well as the average optical density value[0.15(0.14,0.17)vs.0.18(0.17,0.21);0.28(0.26,0.33)vs.0.36(0.33,0.37);0.23(0.22,0.29)vs.0.30(0.28,0.42),respectively,P＜0.05],which was similar to that in the healthy keratinized gingiva.Conclusion:The lack of rete pegs and inflammato-ry factors were common in soft tissue with jaw reconstruction.FGG can improve the quality of the epithe-lium and may improve the stability of the mucosa around implants.

Application of double-layer soft tissue suture closure technique in the surgical treat-ment of patients with mandible medication-related osteonecrosis of the jaw of early and medium stages / 北京大学学报(医学版)

Objective:To investigate the clinical application effect of double-layer soft tissue(DLST)suture closure technique in patients with mandible medication-related osteonecrosis of the jaw(MRONJ)of early and medium stages resulted in application of anti-bone-resorptive drugs.Methods:Early to me-dium stage mandible MRONJ patients who underwent surgical treatment in the fourth ward of Peking Uni-versity School and Hospital of Stomatology from October 2021 to September 2022 were included.Clinical information of the patients were collected,including primary disease,concomitant disease,medication regimen(drug type,duration of medication),MRONJ stage,clinical symptoms,imaging manifestations,etc.During surgery,after using marginal mandibulae resection to remove the necrotic bone,the wound was closed using DLST closure technique.Regular post-operative follow-up was performed to evaluate the therapeutic effect and complications of the DLST technique,the pain score and functional status of the patiens were evaluated.Results:This study totally included 13 patients,12 women and 1 man,aged(66.69±13.14)years.Seven patients had osteoporosis,2 had lung cancer,3 had breast cancer and 1 had prostate cancer among their primary diseases;7 had no concomitant diseases,2 had diabetes melli-tus,2 had cardiovascular disease and 1 had dry syndrome.Intravenous zoledronic acid were used in 9 patients,the average duration was(37.7±20.0)months,and other drugs,such as letrozole tablets were taken in 7 patients at the same time;Denosumab injection was used in 3 patients for an average of(10.3±11.9)months;Alendronate sodium tablets were taken in 5 patients for an average of(55.20± 27.20)months,and prednisone acetate tablets or acarbose tablets were taken to varying degrees in 2 pa-tients.The average post-operative follow-up was 11.9 months(9 to 17 months),and all the 13 patients were cured without complications,such as pus overflow and so forth.The pre-operative score of Karnof-sky performance status(KPS)in the patients was 68.46±14.05,and the post-operative score was 82.31±15.36,and the difference was statistically significant(P＜0.05).The pre-operative score of visual analogue scale(VAS)in the patients was 5.77±0.73 and the post-operative score was 0.38±0.51,and the difference had statistical significance(P＜0.001).Conclusion:The double-layer soft tissue suture closure technique can achieve good clinical results in patients with MRONJ of the man-dible using anti-bone-resorptive drugs alone,and can provide clinical treatment ideas for MRONJ patients with more complicated drug use.

Characteristics,advantages and application of osteogenic differentiation of jaw bone marrow mesenchymal stem cells / 中国组织工程研究

BACKGROUND:The repair of maxillofacial bone tissue defects is a hot and difficult point in current research and the selection of seed cells is the key.Jaw bone marrow mesenchymal stem cells are adult mesenchymal stem cells that exist in the jaw bone.They have advantages in the application of maxillofacial tissue regeneration. OBJECTIVE:To summarize the biological characteristics,osteogenic differentiation advantages of jaw bone marrow mesenchymal stem cells,and the effects of drugs,in vivo environment,and microRNAs on the osteogenic differentiation of jaw bone marrow mesenchymal stem cells. METHODS:Computers were used to perform literature retrieval in PubMed and CNKI.Chinese and English search terms were"oral,bone tissue engineering,stem cells".405 articles were retrieved and downloaded.The articles were screened according to the inclusion and exclusion criteria and 70 articles were finally included for literature review. RESULTS AND CONCLUSION:Jaw bone marrow mesenchymal stem cells were excellent seed cells for oral bone tissue engineering,and had good proliferation and osteogenic differentiation potential.Drugs,in vivo environment and microRNAs could regulate the osteogenic differentiation of jaw bone marrow mesenchymal stem cells.However,the research on jaw bone marrow mesenchymal stem cells was still in the initial stage,so more research with strong demonstration is needed to confirm that jaw bone marrow mesenchymal stem cells have more advantages in the application of maxillofacial bone tissue regeneration.

Finite element analysis of the influence of scaffold materials on the fixed restoration of edentulous maxillary implants under two designs / 中国组织工程研究

BACKGROUND:In the treatment of edentulous maxillary implants supported fixed repair,the selection of upper scaffold structure materials and the design of different distal implant implantation methods have a close influence on the long-term stability of the whole mouth implant repair. OBJECTIVE:To comprehensively explore the influence of three different materials of upper scaffold and two implant fixation designs on the biomechanics of the fixed maxillary implant repair based on the three-dimensional finite element method. METHODS:Based on the conical beam CT data of a healthy adult with normal jaws,the Mimics software was used to separate the maxillary and maxillary dentin three-dimensional solid models,and the Geomagic Studio software was used to construct the three-dimensional finite element model of denture with denture implant and fixed maxillary arch combined with specific model parameters.According to the different designs of distal implants in the maxillary posterior region,two scheme models were established.Scheme 1(Design 1)was designed in accordance with the"All-on-4"design used in clinical practice.Two implants were vertically implanted in the bilateral incisor region of the maxilla,and the other two implants were implanted in the bilateral second premolar region at a 30° angle.In scheme 2(Design 2),two implants were vertically implanted in the lateral incisor region of the maxilla,and two short implants were vertically implanted in the posterior region of the maxilla in the bilateral second premolar region.Three materials(titanium,zirconia and polyether ether ketone)were used to assign values to the upper scaffold structure in the two designs,and six different models were obtained.The biomechanical effects of the implant,surrounding bone tissue and the upper scaffold structure were compared and analyzed in the oblique loading direction. RESULTS AND CONCLUSION:(1)The maximum stress peaks of all models were distributed in the neck region around the posterior implant and the cortical bone under the two edentulous implant fixed restoration schemes,regardless of the material of the upper scaffold.(2)Compared with the alternative design of Design 2,which adopted vertical implantation of short implants,Design 1 showed a more ideal stress distribution on the maxilla.(3)The scaffold model constructed by polyether ether ketone material transferred higher stress to the implant and surrounding bone tissue close to the loading zone of the upper jaw bone,followed by titanium and zirconia.As for the support itself,the peak stress of the upper scaffold of polyether ether ketone was significantly lower than that of the zirconia and titanium scaffolds.Zirconia scaffolds were used among the three upper scaffolds to disperse the stress distribution of implant and bone tissue.(4)The results suggest that both designs can be applied to clinical practice.However,from the perspective of biomechanics,the stress distribution of the implant,surrounding bone tissue and upper scaffold in Design 1 is more rational,which is more conducive to the long-term prognosis of fixed implant repair in patients with edentulous jaws.The upper scaffold material has a certain influence on the stress distribution of the implant-bone interface.

Early Dental Failure and Medication-related Osteonecrosis of the Jaw in Patients Treated with Bisphosphonates:A Meta-analysis of Pro-portions / 医学研究杂志

Objective To assess the early dental failure rate and medication-related osteonecrosis of the jaw(MRONJ)incidence in patients treated with bisphosphonates(BPs),and provide evidence for evaluation of clinical risk.Methods Electronic databases,in-cluding Cochrane Library,Wiley Online Library,PubMed,CNKI and Wanfang Data were searched to collect clinical studies concerning early dental failure and medication-related osteonecrosis of the jaw in patients treated with bisphosphonates.The data were collected from inception until May 2022.The meta-analysis was conducted using Stata 15.Osoftware.Results A total of 13 clinical observational stud-ies involving 1261 implants,wherein 1182 implants were placed in patients who took bisphosphonate orally,and 79 implants were placed in patients treated with intravenous bisphosphonate.In patients who had orally administrated bisphosphonates,the pooled early dental fail-ure rate was 1.7％(95％CI:0.3％-3.9％),and the MRONJ incidence was 0.Among patients treated with intravenous bisphospho-nate,the pooled early dental failure rate was 0,and the MRONJ incidence was 5.6％.Conclusion The early dental failure rate and MRONJ incidence in patients who take bisphosphonates orally is as low as in a healthy population.On account of the relatively high risk of post-operative MRONJ in patients treated with intravenous bisphosphonates,clinical indications must be opted prudently.

Clinical application of perforator vessel location guide plate for fibular musculocutaneous flaps / 口腔疾病防治

Objective@#Based on 3D printing technology, explore the precision of a perforator vessel location guide plate for fibular musculocutaneous flaps before the transplantation of fibular osteocutaneous flaps and evaluate its application effects.@*Methods@#This study was reviewed and approved by the ethics committee, and informed consent was obtained from the patients. From May 2019 to October 2022, 14 patients with jaw defects who needed to undergo fibular perforator flap transplantation at the First Affiliated Hospital of Xinjiang Medical University were selected. For the seven patients in the guide plate group, CTA was combined with Mimics software to reconstruct both lower limbs, and the perforator vessel positioning guide for locating perforator vessels was designed; the two ends of the guide plate were designed as fixed ends, with the upper end fixed to the knee joint and the lower end fixed to the ankle joint, and the guide plate was fabricated by a 3D printer. For the seven patients in the control group, a conventional handheld Doppler probe was used for perforator vessel location. The average operation time, bleeding volume, recovery time, deviation of perforator vessel location, postoperative flap-related complications, postoperative donor site shape satisfaction, and lower extremity functional scale (LEFS) score were recorded. SPSS 25.0 software was used for statistical analysis.@*Results@#The average operation time, bleeding volume, recovery time, deviation of perforator vessel location and postoperative donor site shape satisfaction were significantly better in the guide plate group than in the control group (P<0.05); moreover, the differences in postoperative flap-related complications and LEFS scores were not statistically significant (P>0.05).@*Conclusion@#Based on 3D printing technology, fibular musculocutaneous flap perforator vessels can be more accurately located using a guide plate and the knee and ankle as fixed points, and this method can effectively stabilize the guide position, prevent soft tissue offset, and improve positioning accuracy and thus deserves to be generalized.

Research progress on applications and mechanisms of osteogenesis effect of magnetic fields in oral field / 口腔疾病防治

@#Magnetic fields are safe and used in noninvasive physical therapies. Numerous studies have confirmed that magnetic fields have good osteogenic effects and certain value for clinical application in accelerating orthodontic tooth movement, promoting bone-implant integration, promoting fracture healing and improving the effects of distraction osteogenesis. Magnetic fields are expected to become applied as effective auxiliary methods for treating oral diseases. To support the clinical application of magnetic fields, this article reviews the applications of magnetic fields in the oral cavity, the biological effects on bone cells and the molecular mechanisms through which magnetic fields regulate bone metabolism. The biological effects of magnetic fields on bone cells include promoting osteogenesis by osteoblasts and mesenchymal stem cells and inhibiting bone resorption by osteoclasts. At the molecular level, bone cells sense and respond to magnetic stimulation, and through various mechanisms, such as displacement currents, Lorentz forces, and free radical pair effects, stimuli are transformed into biologically recognizable electrical signals that activate complex downstream signaling pathways, such as the P2 purinergic receptor signaling pathway, adenosine receptor signaling pathway, transforming growth factor-β receptor signaling pathway, mammalian target of rapamycin (mTOR) pathway, and Notch pathway. In addition, magnetic parameters, which are the factors affecting the osteogenic effects of magnetic fields, are discussed. However, the mechanisms of the osteogenic effects of magnetic fields are unclear, and further studies of these mechanisms could provide effective strategies for bone regeneration and periodontal tissue regeneration. In addition, considering the target of magnetic field therapies, combination with other drugs could lead to new strategies for the treatment of oral diseases.

Long-term consequences of osteoporosis therapy with bisphosphonates

ABSTRACT Bisphosphonates (BPs) are medications widely used in clinical practice to treat osteoporosis and reduce fragility fractures. Its beneficial effects on bone tissue have been consolidated in the literature for the last decades. They have a high affinity for bone hydroxyapatite crystals, and most bisphosphonates remain on the bone surface for a long period of time. Benefits of long-term use of BPs: Large and important trials (Fracture Intervention Trial Long-term Extension and Health Outcomes and Reduced Incidence with Zoledronic acid Once Yearly-Pivotal Fracture Trial) with extended use of alendronate (up to 10 years) and zoledronate (up to 6 years) evidenced significant gain of bone mineral density (BMD) and vertebral fracture risk reduction. Risks of long-term use of BPs: The extended use of antiresorptive therapy has drawn attention to two extremely rare, although severe, adverse events. That is, atypical femoral fracture and medication-related osteonecrosis of the jaw are more common in patients with high cumulative doses and longer duration of therapy. BPs have demonstrated safety and effectiveness throughout the years and evidenced increased BMD and reduced fracture risks, resulting in reduced morbimortality, and improved quality of life. These benefits overweight the risks of rare adverse events.

Knowledge of Brazilian dentists about bisphosphonate-associated osteonecrosis of the jaw / Conhecimento de dentistas brasileiros sobre a osteonecrose dos maxilares associada ao uso de bisfosfonatos

Osteonecrosis of the jaw associated with bisphosphonate use is a matter of utmost importance in clinical practice for the safe treatment of patients using this medication. Objective: The aim of this study was to evaluate the level of knowledge of dentists who carry out clinical practice about bisphosphonate-associated jaw osteonecrosis. Material and Methods: The methodology used in the present research consisted of a non-probability sampling approach for the selection of participants. To conduct the study, a questionnaire created on the Google Forms platform was sent via Direct on Instagram to the professionals who agreed to participate. The data were sent for analysis, using the frequency for each response, and the professionals were divided into subcategories according to their time of professional practice. Results: Participants were familiar with the purpose of the medication (65%) or had heard of it (34%); regarding the professionals' opinion on their knowledge and practice about bisphosphonate-related osteonecrosis a significant percentage (93.24%) responded positively regarding the existence of side effects resulting from the therapeutic use of bisphosphonates and 48.65% self-evaluated their level of knowledge on the subject as insufficient. Conclusion: The study reveals that almost all participating dentists have good knowledge about the effects caused by bisphosphonates, but some of them still do not feel specifically confident about the management and knowledge of jaw osteonecrosis (AU)

A osteonecrose dos maxilares associada ao uso de bisfosfonatos é um assunto de suma importância na prática clínica para o atendimento seguro dos pacientes que fazem uso terapêutico do medicamento. Objetivo: O objetivo deste trabalho foi avaliar o nível de conhecimento de cirurgiões dentistas que realizam atendimento clínico acerca da osteonecrose dos maxilares associada ao uso dos bisfosfonatos. Material e Métodos: A metodologia utilizada na presente pesquisa consistiu em uma abordagem de amostragem não probabilística para a seleção dos participantes. Para conduzir o estudo, enviamos um questionário criado na plataforma Google Forms via Direct no Instagram para os profissionais que concordaram em participar. Os dados foram enviados para análise, usando a frequência para cada resposta, sendo que os profissionais foram divididos em subcategorias por tempo de formação. Resultados: Os participantes estavam familiarizados com a finalidade do medicamento (65%) ou já haviam ouvido falar deles (34%); em relação à opinião dos profissionais sobre seu conhecimento e prática acerca da osteonecrose relacionada aos bisfosfonatos, observou-se que 48,65% autoavaliaram seu nível de conhecimento sobre o assunto como insuficiente e uma parcela expressiva (93,24%) respondeu positivamente em relação à existência de efeitos colaterais decorrentes ao uso terapêutico dos bisfosfonatos. Conclusão: O estudo revela que quase todos os dentistas participantes possuem um bom conhecimento acerca dos efeitos causados pelos bisfosfonatos, mas que parte deles ainda não se sentem seguros especificamente em relação ao manejo e conhecimento da osteonecrose dos maxilares (AU)

Oral rehabilitation with removable partial denture in a patient undergoing partial maxillectomy: a case report / Reabilitação oral com prótese parcial removível em paciente submetido a maxilectomia parcial: relato de caso

ABSTRACT The Removable Partial Denture stands as an effective rehabilitation choice for patients who have undergone partial maxillectomy surgery due to maxillary tumors, involving the partial surgical removal of the maxillary bone. Removable partial denture are meticulously designed to restore masticatory, phonetic, and aesthetic functions, thereby contributing significantly to enhancing self-esteem and aiding patients in resuming social activities. During the patient's history-taking phase, it is of paramount importance to assess the patient's overall health, psychological state, expectations, and limitations. Ensuring regular follow-ups is imperative to prevent complications and to guarantee the durability of the prosthesis. Prosthetic planning constitutes a critical phase and can pose challenges, especially in achieving proper retention, stability, and suitable supports. Factors such as the defect size, the number of remaining teeth, and the amount of remaining bone structures can influence the treatment prognosis. It is crucial to emphasize that lack of adequate planning can lead to rehabilitation failures, resulting in discomfort, compromised functionality, and even potential harm to the patient's health. In this context, this study aims to present a successful clinical case of a patient who underwent partial maxillectomy and was rehabilitated through a Removable Partial Denture fixed with clasps on the entire left upper hemi-arch. This case vividly illustrates the importance of a personalized approach to prosthetic rehabilitation in patients with partial maxillectomy, taking into account the specificities of each case and highlighting the necessity of interdisciplinary collaboration to achieve satisfactory outcomes.

RESUMO A prótese parcial removível é uma opção eficaz de reabilitação para pacientes que passaram por cirurgia de maxilectomia parcial em decorrência de tumores maxilares, ou seja, remoção cirúrgica parcial do osso maxilar. A prótese parcial removível deve ser projetada para recuperar as funções mastigatória, fonética e estética, contribuindo assim na melhoria da autoestima e ajudando o paciente a retornar às atividades sociais. Durante a anamnese, é de grande importância verificar o estado geral e psicológico do paciente, suas expectativas e limitações, garantir o acompanhamento frequente para evitar complicações e garantir a durabilidade da prótese. O planejamento protético é uma etapa crítica e pode apresentar desafios, especialmente na obtenção de retenção, estabilidade e suportes adequados. Fatores como o tamanho do defeito, o número de dentes remanescentes e a quantidade de estruturas ósseas remanescentes podem interferir no prognóstico do tratamento. É importante ressaltar que a falta de planejamento pode levar a falhas na reabilitação, resultando em desconforto, má funcionalidade e até mesmo danos à saúde do paciente. Nesse contexto, o presente trabalho tem como objetivo apresentar um caso clínico de sucesso de uma paciente que foi submetida a uma maxilectomia parcial e reabilitada por meio de uma prótese parcial removível fixada por grampos em todo o hemiarco superior esquerdo. Este caso ilustra a importância de uma abordagem personalizada para a reabilitação protética em pacientes com maxilectomia parcial, considerando as particularidades de cada caso e a colaboração interdisciplinar para a obtenção de resultados satisfatórios.

Cirugía virtual guiada para rehabilitación implantosoportada de maxilar edéntulo con carga inmediata / Virtual guided surgery for implantsupported rehabilitation of the edentulous maxilla with immediate loading

Objetivo: Presentar el relato de un caso clínico de cirugía virtual guiada para rehabilitación implantosoportada de maxilar edéntulo con carga inmediata. Relato del caso: Paciente, edéntulo total en ambos maxilares, expresó su deseo de cambiar la prótesis total superior removible por una prótesis total fija sobre implantes. Durante la evaluación clínica, se observaron condiciones biológicas favorables al tratamiento como, adecuada faja de tejido queratinizado y leve reabsorción ósea. Como tratamiento se le sugiere al paciente, una planificación inversa, asistida por cirugía virtual guiada, utilizando un prototipo de guía quirúrgica para la colocación de seis implantes dentales en el maxilar y la instalación de una prótesis protocolo de carga inmediata. Conclusiones: Los resultados nos permiten concluir que la cirugía virtual guiada por computadora para rehabilitación protésica implantosoportada de maxilar edéntulo, con carga inmediata, proporciona precisión en los procedimientos quirúrgicos, es fundamental para la confección de prótesis inmediatas, representa una alternativa mínimamente invasiva y el resultado complace a los pacientes.

Objective: present the report of a clinical case of a virtual guided surgery for implant-supported rehabilitation of the edentulous maxilla with immediate loading. Case report: Patient, bi-maxillary edentulous expressed the desire to replace the removable upper total prothesis for a total fixed prothesis on implants. During the clinical evaluation, favorable biological conditions for treatment were observed, such as adequate keratinized tissue band and mild bone resorption. As part of the treatment, the patient was recommended a reverse planning approach, assisted by virtual guided surgery. This involved a prototype surgical guide for the fixation of six dental implants in the maxilla and the installation of an immediate loading protocol prosthesis. Conclusions: The results lead us to conclude that computer-guided virtual surgery for implant-supported prosthetic rehabilitation of the edentulous maxilla with immediate loading, provides a high precision in surgical procedures. It is essential to fabrication of immediate prostheses, represents a minimally invasive alternative, and results in patient satisfaction.