An Analysis of Stimulating Occlusal Trauma on Condyle Using Three-Dimensional Finite Element Model / 昆明医科大学学报

Objective To provide evidence for the relationship between TMD and occlusal trauma by studying the mechanics influence and displacement of condyle by building the three dimensional finite element analysis model andstimulating the abnormal bite force leading occlusal trauma.Methods We collected DICOM date of healthy male volunteers with normal occlusal relationship using CBCT scan with constraint on condylar top and formed the finite model with divide mesh.Two conditions were built: (1) We operated different vertical load on the left mandibular molar occlusal surface; (2) We operated different buccal direction load on the same modelto study the mechanic change on left condylar.Results When the three dimensional finite model of mandible was built, the mechanic region of condyle stayed the same but the stress and tension increased accordingly as the loda duplicate rose. As the same buccal operation load was operated,the stress and tension became larger and the displacement became longer.Conclusion The abnormal bite force causing occlusal trauma can change mechanic conduct on condyle and lead to the pathological change of condyle.

Combination of periodontal, orthodontic and endodontic therapy in upper anterior teeth with hopeless prognosis and long-time follow-up:a case report / 北京大学学报(医学版)

It is complicated to decide the treatment plan of hopeless anterior teeth in esthetic zone due to severe periodontitis, periodontal-endodontic combined lesion or teeth trauma.The optional treatment plan for this kind of teeth includes retention after periodontal treatment, extraction and implant treatment, extraction and prosthodontic treatment and so on.To make an appropriate treatment plan, patients'' periodontal conditions, periodontal biotype, local anatomy, esthetic demand, economic condition and social psychological status should be comprehensively considered.A combine of periodontal, endodontic and orthodontic therapy may achieve a good treatment effect in hopeless anterior teeth with severe periodontal destruction, tooth extrusion and occlusal trauma.In this case, a 20-year-old female who presented with symptoms of bleeding on brushing and upper incisors loosening for 1 month came to the Department of Periodontology, Peking University School and Hospital of Stomatology.The clinical examinations revealed that the patient''s right upper incisor had signs of mobility (Ⅲ°), intrusion of 1-2 mm, and probing depth (PD) of 9-10 mm.The periapical radiograph showed that the alveolar bone of right upper incisor absorbed horizontally to the apex.And the patients showed Angle Ⅱ° malocclusion with Ⅱ° overbite in anterior teeth and maxillary protrusion.A diagnosis of aggressive periodontitis and Angle Ⅱ° malocclusion was made.The treatment of this patient lasts for 5 years which include periodontal initial therapy, orthodontic therapy, guided tissue regeneration (GTR) of right upper incisor and supportive periodontal therapy and the clinical result is fine.A hopeless upper incisor was successfully retained and the longtime clinical condition was stable.The strategy of retention of hopeless upper anterior teeth, the relationship of periodontal treatment and orthodontic treatment, and the indications of periodontal and orthodontic combined therapy were also discussed on the basis of this case.Generally, the positive factors in retention of hopeless teeth includes young age, absence of systemic conditions, strong motivation for maintaining the tooth, single root anatomy, integrated dentition, good response to cause-related therapy, intrabony alveolar bone defect, thick periodontal biotype, and regular supportive periodontal therapy.And in the progress of orthodontic therapy, regular supportive periodontal therapy and good plaque control is extremely important.

Afecciones pulpares de origen no infeccioso en órganos dentarios con oclusión traumática / Non-infectious pulpal disorders in dental organs with occlusal trauma

Introducción: la oclusión traumática se define como una alteración en las relaciones oclusales del sistema masticatorio, lo cual podría ser un factor conducente a un proceso inflamatorio en el ligamento periodontal, en la pulpa dental, y en tejidos blandos sensitivos. Objetivo: identificar las afecciones pulpares de origen no infeccioso en órganos dentarios con oclusión traumática en pacientes de un hospital del sector público de Mérida, Yucatán, México. Métodos: se realizó un estudio observacional y analítico, en un hospital del sector público de Mérida, Yucatán, México (2014). La muestra estuvo constituida con un total de 156 órganos dentarios de 82 pacientes, de 20 y más años de edad, que presentaron oclusión traumática en dientes permanentes y que mostraron alguna afección en tejido pulpar de origen no infeccioso, de acuerdo con la clasificación de la Academia Americana de Endodoncia. También se incluyó a los pacientes que presentaban caries, fracturas, fisuras, obturaciones, endodoncia, ortodoncia o trauma dentoalveolar. Se empleó un muestreo No probabilístico, por conveniencia. Se obtuvo el consentimiento informado y voluntario, historia médica y dental, y se realizó la evaluación de los signos y síntomas de dolor, pruebas pulpares (térmicas y eléctricas), palpación y percusión y abordaje diagnóstico con tinción/transiluminación, así como pruebas oclusales con papel de articular y examinación e interpretación de radiografías periapicales. Se utilizó estadística descriptiva. Resultado: hubo ausencia de dolor en 53 por ciento de los 156 órganos dentarios estudiados. Las alteraciones radiográficas se presentaron en 63 por ciento: entre ellas los nódulos pulpares tuvieron el mayor porcentaje (25 por ciento). La pulpitis fue reversible en 37 por ciento (n= 58); la oclusión traumática más frecuente fue la maloclusión (n= 49). En los 156 órganos dentarios estudiados, el signo clínico que mostró mayor frecuencia fue el desgaste en esmalte (n= 56). Conclusiones: las afecciones pulpares de origen no infeccioso se presentaron en alto porcentaje de dientes permanentes de pacientes con oclusión traumática(AU)

Introduction: Occlusal trauma is defined as an alteration in the occlusal relationships of the masticatory system, which may lead to inflammation of the periodontal ligament, the dental pulp and sensitive soft tissues. Objective: Iidentify non-infectious pulpal disorders in dental organs with occlusal trauma of patients from a public hospital in Mérida, Yucatán. Methods: An observational analytical study was conducted at a public hospital in Mérida, Yucatán, Mexico (2014). The study universe was 156 dental organs of 82 patients aged 20 years and over with occlusal trauma in permanent teeth and some degree of non-infectious pulp tissue disorder, based on the classification of the American Academy of Endodontics. Patients were also included who presented caries, fractures, fissures, fillings, endodontic treatment, orthodontic treatment or dentoalveolar trauma. Convenience non-probability sampling was applied. Voluntary informed consent was obtained. Medical and dental records were examined. An evaluation was carried out of pain signs and symptoms. Thermal and electric pulp tests were performed, as well as palpation, percussion and diagnostic staining/transillumination. Occlusal testing was conducted using articulating paper. Periapical radiographs were examined and interpreted. Descriptive statistics were used. Result: There was no pain in 53 percent of the dental organs studied. Radiographic alterations were present in 63 percent; the most common were pulp nodes (25 percent). Pulpitis was reversible in 37 percent (n= 58), and the most frequent occlusal trauma was malocclusion (n= 49). In the 156 teeth studied, the most common clinical sign was enamel wear (n= 56). Conclusions: Non-infectious pulpal disorders were present in a large number of permanent teeth of patients with occlusal trauma(AU)

Trauma oclusal, sobrecarga oclusal e suas consequências sobre os tecidos periodontais e peri-implantares / Occlusal trauma, occlusal overload and its consequences on periodontal and peri implant tissues

Agentes patogênicos presentes no biofilme dental têm sido considerados como fator etiológico primário das doenças periodontais. Entretanto, não existe um consenso sobre o efeito das forças oclusais no periodonto. O objetivo desse trabalho é avaliar a influência do trauma e da sobrecarga oclusal sobre a ocorrência de periodontite e peri-implantite respectivamente. Além disso, avaliar se há diferença na resposta tecidual entre dentes e implantes submetidos a tais discrepâncias. A partir da literatura estudada, pode-se concluir que apesar do trauma e da sobrecarga oclusal influenciarem negativamente a severidade da periodontite e da peri-implantite respectivamente, uma relação de causalidade ainda não está definida. Quando submetidos à sobrecarga oclusal, implantes são mais susceptíveis à perda da crista óssea alveolar quando comparados a dentes sob trauma.

Pathogens present in the dental biofilm have been considered as primary etiological factor of periodontal diseases. However, there is no consensus on the effect of occlusal forces in the periodontium. The aim of this review was to evaluate the influence of occlusal trauma and occlusal overload on the occurrence of periodontitis and periimplantitis respectively, and if there is a difference on tissue responses between theeth and implants subjected to such discrepancies. From this literature review it may be concluded that despite occlusal trauma and occlusal overload negatively influence the severity of periodontitis, causal relationship is not yet defined. When submitted to occlusal overload, implants are more likely to loss of bone crest than teeth submitted to occlusal trauma.

Diagnóstico do trauma oclusal: extrapolações para a região óssea peri-implantar podem ser feitas / Diagnosis of occlusal trauma:extrapolations for peri-implant bone region can be done

As imagens oferecem uma linguagem que revela o dinamismo tecidual ósseo. A densidade óssea e a configuração espacial variam em suas estruturas e indicam uma menor ou maior reação e capacidade de adaptação às demandas funcionais, como cargas mastigatórias nos dentes naturais ou nos implantes osseointegrados. No planejamento de um tratamento reabilitador, é fundamental planejar a distribuição de carga e avaliar as condições dos dentes remanescentes e sua relação com o osso vizinho. Detectar a resposta óssea ao trauma oclusal preexistente pode favorecer uma avaliação mais precisa das condições mastigatórias e dos vícios parafuncionais: uma verdadeira história prévia funcional dos dentes remanescentes. Ressalta-se que as interferências e sobrecargas oclusais demoram meses, ou anos, para induzir os sinais e sintomas clássicos do trauma oclusal enquanto entidade clínica. Quando o dente apresenta-se com necrose pulpar e com sinais de trauma oclusal, o ideal será direcionar a anamnese e exames para um diagnóstico de traumatismo dentário superposto, mesmo em dentes posteriores. Não há fundamentação científica segura para afirmar-se que interferências ou sobrecargas oclusais provocam necrose pulpar. Um questionamento muito comum: até que ponto as forças ortodônticas de ancoragem podem ser aplicadas nos implantes osseointegrados? As forças ortodônticas não superam, em qualquer situação, a intensidade, amplitude e variabilidade das forças oclusais. Se um implante pode receber cargas mastigatórias, o mesmo pode se aplicar às forças ortodônticas de ancoragem.

Images provide a language to describe the dynamics of bone and tissue. Bone density and space distributionvary and indicate greater or lower reaction and adaptation to functional demands, such as masticatory loads,on natural teeth or osseointegrated implants. In rehabilitation, load distributions have to be planned, and theremaining teeth and their relation with neighboring bone should be evaluated. The detection of bone responsesto pre-existing occlusal trauma may provide a more accurate evaluation of masticatory conditions and parafunctionalhabits, that is, a true functional history of remaining teeth. Occlusal interference and overloads takemonths or years to induce classical signs and symptoms of occlusal trauma as a clinical entity. When a toothhas pulp necrosis and signs of occlusal trauma, the evaluation of history, as well as all tests, should be directedto the diagnosis of superposed dental trauma even when posterior teeth are affected. There is no scientific basisto confirm that occlusal interferences and overloads lead to pulp necrosis. A frequent question: Up to whatpoint should orthodontic forces be applied to osseointegrated implants? Orthodontic forces are not greater, inany situation, than occlusal forces in terms of intensity, amplitude and variability. If an implant can bear masticatory loads, it may also receive orthodontic forces resulting from anchorage.

Occlusal trauma can not be compared to orthodontic movement or Occlusal trauma in orthodontic practice and V-shaped recession

The mechanisms of tissue changes induced by occlusal trauma are in no way comparable to orthodontic movement. In both events the primary cause is of a physical nature, but the forces delivered to dental tissues exhibit completely different characteristics in terms of intensity, duration, direction, distribution, frequency and form of uptake by periodontal tissues. Consequently, the tissue effects induced by occlusal trauma are different from orthodontic movement. It can be argued that occlusal trauma generates a pathological tissue injury in an attempt to adapt to new excessive functional demands. Orthodontic movement, in turn,performs physiological periodontal bone remodeling to change the position of the teeth in a well-planned manner, eventually restoring normalcy.

Os mecanismos das alterações teciduais induzidas pelo trauma oclusal não são minimamente comparáveis aos do movimento ortodôntico. Embora ambos os eventos tenham uma causa primária de natureza física, essas forças aplicadas sobre os tecidos dentários têm características completamente distintas na intensidade, tempo, direção, distribuição, frequência e forma de absorção pelos tecidos periodontais. Por consequência, os efeitos teciduais induzidos no trauma oclusal são diferentes do movimento ortodôntico. Pode-se afirmar que o trauma oclusal gera uma lesão tecidual de natureza patológica, na tentativa de se adaptar a novas demandas funcionais excessivas. Por sua vez, o movimento ortodôntico utiliza-se da remodelação óssea periodontal fisiológica para mudar o dente de posição, de forma planejada e com posterior restabelecimento da normalidade.