Impact of low intensity pulsed ultrasound on volumetric root resorption of maxillary incisors in patients treated with clear aligner therapy: A retrospective study

ABSTRACT Objective: The aim of this study was to evaluate the volumetric root resorption in maxillary incisors following clear aligner therapy (CAT) with low-intensity pulsed ultrasound (LIPUS), and compare the results to CAT alone. Material and Methods: This retrospective study evaluated pretreatment (T0) and post-treatment (T1) cone-beam computed tomography imaging of 42 adult patients. Twenty-one patients (14 females, 7 males, mean age= 38.1±12.96 years) were treated using CAT with LIPUS device, whereas the other twenty-one matching controls patients (15 females, 6 males, mean age= 35.6±11.7 years) were treated using CAT alone. Images were analyzed and a segmentation protocol was applied on the maxillary incisors. Each segmented tooth volume was exported as a surface mesh in the Visualization Toolkit (VTK) file format. The VTK files for all maxillary incisors were coded and corresponding teeth volumes from T0 and T1 were superimposed. Clipping the crown of each tooth was done, then measurements of root volumes and differences between groups were performed. Changes in root volumes were assessed (p<0.05). Results: Root loss was evident in all teeth in both groups, but was significantly increased in all maxillary incisors of the control group (p<0.001) and in upper left central incisor of LIPUS group (p=0.009). When both groups were compared, there was statistically significant minimal volumetric root loss in LIPUS group (3.50-7.32 mm3), when compared to control group (11.48-12.95 mm3) (p<0.05). Conclusion: LIPUS group showed less volumetric root resorption compared to control group during the studied treatment time using clear aligners.

RESUMO Objetivo: O objetivo deste estudo foi avaliar volumetricamente a reabsorção radicular em incisivos superiores após tratamento com alinhadores transparentes (CAT) com e sem uso adjuvante de ultrassom de baixa intensidade (LIPUS). Material e Métodos: Esse estudo retrospectivo avaliou imagens de tomografia computadorizada de feixe cônico pré-tratamento (T0) e pós-tratamento (T1) de 42 pacientes adultos: 21 pacientes (14 mulheres, 7 homens, idade média= 38,1±12,96 anos) foram tratados com CAT e LIPUS, enquanto os outros 21 pacientes controles correspondentes (15 mulheres, 6 homens, idade média= 35,6±11,7 anos) foram tratados apenas com CAT. As imagens foram analisadas e foi aplicado um protocolo de segmentação dos incisivos superiores. Os volumes de cada dente segmentado foram exportados como malhas de superfície, em arquivos no formato Visualization Toolkit (VTK). Os arquivos VTK de todos os incisivos superiores foram codificados e foram sobrepostos os volumes dos dentes correspondentes a T0 e T1. Foi realizada a clipagem da coroa de cada dente e, em seguida, foram realizadas medições dos volumes radiculares e comparadas as diferenças entre os grupos, avaliando-se as alterações nos volumes de raízes (p<0,05). Resultados: A perda radicular foi evidente em todos os dentes em ambos os grupos, mas foi significativamente maior em todos os incisivos superiores do grupo controle (p<0,001) e no incisivo central superior esquerdo do grupo LIPUS (p=0,009). Quando ambos os grupos foram comparados, houve perda volumétrica mínima estatisticamente significativa no grupo LIPUS (3,50-7,32 mm3), em comparação ao grupo controle (11,48-12,95 mm3) (p<0,05). Conclusão: O grupo LIPUS apresentou menor volume de reabsorção radicular, em comparação ao grupo controle, durante o tempo de tratamento estudado usando alinhadores transparentes.

Effects of low-level laser on the repair of orthodontically induced inflammatory root resorption: a systematic review of studies in rats / Efectos del láser de bajo nivel en la reparación de la reabsorción radicular inflamatoria inducida por ortodoncia: una revisión sistemática de estudios en ratas

Orthodontically induced inflammatory root resorption (OIIRR) is a complication of dental treatment which consists of the degradation of local tissue due to an inflammatory reaction provoked by inappropriate orthodontic stimulus. The aim of the present systematic review was to assess the effectiveness of low-level laser therapy (LLLT) in reducing orthodontically induced inflammatory root resorption (OIIRR) in animal models. A systematic review was carried out in the MEDLINE, EMBASE and LILACS databases. Studies of interventions in animals were selected which analysed the effect of LLLT on OIIRR repair. The risk of bias was analysed through the 10 domains of the SYRCLE RoB tool for animal studies. Seventy-one studies were found; 27 were eliminated as duplicates and 44 titles/abstracts were analysed. Of these, 38 were excluded, and five studies were included for qualitative analysis. In 66.6 % of the studies included, the authors state that LLLT was effective in the inhibition/repair of OIIRR. In histological analysis it was observed that root resorption was significantly less in animals treated with laser as compared to the control. Furthermore, LLLT accelerated cicatrization after OIIRR. Laser proved effective in reducing root resorption lacunae and shortening the inflammatory process induced by the application of orthodontic force.

La resorción radicular inflamatoria inducida por tratamiento ortodontico (RRIITO) es una complicación del tratamiento odontológico que consiste en la degradación del tejido local debido a una reacción inflamación provocada por un estímulo ortodóntico inadecuado. El objetivo fue analizar la efectividad de la terapia láser de baja intensidad (LBI) en la disminución de RRIITO en ratas. Se realizó una revisión sistemática en las bases MEDLINE, EMBASE y LILACS. Fueron utilizados los términos 'resorción radicular', 'láser de baja intensidad', 'fototerapia', 'tratamiento ortodóntico', 'movimiento dental'. Fueron seleccionados estudios de intervención en animales, que analizaron el efecto del LBI en la reparación de la RRIITO. Los riesgos de sesgos fueron analizados mediante los 10 domínios de la herramienta SYRCLE RoB para estudios en animales. 71 estudios fueron encontrados, siendo eliminados 27 duplicados, y analizados 44 títulos/abstracts; de estos, fueron incluídos 5 estudios para análisis cualitativa. El 66,6 % de los estudios incluidos afirman que el LBI fue efectivo em reparar la RRIITO. En el análisis histológico se observó que la RRIITO fue significativamente menor en animales tratados con láser en comparación con el control. Además de eso, el LBI aceleró el proceso de cicatrización de la RRIITO. El láser se mostró efectivo en reducir las lagunas de resorción radicular y acortar el proceso inflamatorio inducido por la aplicación de fuerzas ortodonticas.

Local injection of Icariin on orthodontically induced inflammatory root resorption in rats / 西安交通大学学报(医学版)

Objective To study the influence of local administration of Icariin on orthodontically induced inflammatory root resorption (OIIRR ).Methods After rat models of orthodontic root movement were successfully established,rats were injected with 200 mg/kg Icariin (Icariin group)or saline (positive control group), respectively.Left maxillary served as the negative control group.The resorption pit of root surface was measured using scanning electron microscopy (SEM), HE staining, and tartrate resistant acid phosphatase (TRAP ). Results The level of TRAP positive cells and root resorption score in Icariin group were significantly lower than those in the positive control group (P 0.05).Conclusion Local administration of Icariin may reduce the degree of orthodontically induced resorption.

Reabsorción radicular inflamatoria en sujetos con tratamiento ortodóntico. Cartagena (Colombia) / Inflamatory root resorption in orthodontic treatment subjects. Cartagena (Colombia)

Objetivo: Determinar la ocurrencia de Reabsorción Radicular Inflamatoria en sujetos sometidos a movimiento dental con cuatro técnicas de ortodoncia. Materiales y métodos: Estudio de cohorte con seguimiento a un año, evaluando la reabsorción radicular inflamatoria con cuatro técnicas de ortodoncia, a partir de la escala de Levander and Malmgren. Las mediciones se realizaron en 176 dientes, usando tres radiografías periapicales por participante cada tres meses. Los datos fueron analizados a través de proporciones de incidencia. El Riesgo Relativo se utilizó para la asociación entre la presencia de reabsorción y la técnica de ortodoncia, con intervalos de confianza del 95 %. Para la significancia estadística se aplicaron los test de Kruskal Wallis, Mc-Nemar y Fischer. Se realizó un análisis multivariable por regresión logística. Resultados: La incidencia de Reabsorción Radicular fue del 68,2 %, presentándose a los nueve y doce meses. Se observaron cambios radiculares con grado 1 en 8,5 % de los dientes y grado 2 con 2,8 %, siendo laterales los de mayor proporción (6,3%). En los dientes sometidos a la técnica de Arco de canto se encontró un riesgo 3,3 veces mayor en comparación con las técnicas pre-ajustadas. Conclusiones: Existe Reabsorción Radicular en los dientes sometidos a movimiento dental durante el tratamiento de ortodoncia, sin embargo, estos cambios se consideran leves y dependen de la biomecánica utilizada en cada técnica.

Objective: To determine the occurrence of root resorption in subjects undergoing tooth movement with orthodontic four techniques. Materials and method: A cohort study with up to one year, evaluating root resorption in orthodontic four techniques. The measurements were made on 176 teeth, using the scale of reabsorption of Levander and rots. Periapical radiographs using three in each individual, which were taken every three months. The data were analyzed using proportions of incidence. To compare the results obtained in each of the techniques are used the risk ratio (RR) with confidence intervals 95 %, the Kruskal Wallis, Mc-Nemar and Fischer"s test. We performed a multivariable logistic regression analysis. Results: The incidence of inflammatory resorption was 68.2, appearing at nine and twelve months, showing contour changes in the first grade in 8.5 % and second grade in 2.8 %. In the teeth subjected to edgewise technique was found 3.3 times higher risk of root resorption compared with other techniques. Conclusions: There is evidence of inflammatory resorption in the contour of the root in teeth subjected to tooth movement during orthodontic treatment, however, these are considered mild and depend on each technique used mechanotherapy.

Apical internal inflammatory root resorption and open apex treated with MTA: a case report / Reabsorção apical inflamatória interna e ápice aberto tratado com MTA: relato de caso

Purpose: Internal inflammatory root resorption is a rare condition, characterized by progressive loss of tooth substance which starts on the root canal wall. Usually the process is asymptomatic and diagnosed upon routine radiographic examination. The following report shows the treatment of a case of periapical lesion and apical internal resorption that reached the external root surface. Case description: A 16 year-old male was referred for a routine dental treatment for oral rehabilitation. Radiographic examination showed a resorptive lesion in the apical third and periapical lesion on tooth 21. Crown down preparation was performed and calcium hydroxide was placed for 2 weeks. An apical plug with white MTA was condensed into the resorption cavity and then the canal was obturated with gutta-percha and AH Plus sealer. The follow-up radiographs showed satisfactory resolution. Conclusion: This report showed the results of the treatment with MTA apical plug. The technique avoided an invasive procedure and presented some advantages, like materials biological properties and capable of sealing.

Objetivo: A reabsorção radicular interna inflamatória é uma condição rara caracterizada por progressiva perda de substância dentária, que se inicia nas paredes do canal radicular. Geralmente o processo é assintomático e diagnosticado em exame radiográfico de rotina. O presente relato de caso mostra o tratamento de um caso de lesão periapical e reabsorção interna apical que atingiu a superfície radicular externa. Descrição do caso: Um paciente do sexo masculino de 16 anos foi encaminhado para tratamento odontológico de rotina para reabilitação oral. O exame radiográfico mostrou uma lesão de reabsorção no terço apical e lesão periapical no dente 21. O preparo coronário foi realizado e hidróxido de cálcio foi colocado por duas semanas. Um tampão com MTA branco foi condensado na cavidade da reabsorção e então o canal foi obturado com guta-percha e cimento AH Plus. As radiografias de acompanhamento mostraram resolução satisfatória. Conclusão: Este caso mostrou os resultados do tratamento com tampão apical de MTA. A técnica evitou um procedimento invasivo e apresentou algumas vantagens, tais como propriedades biológicas dos materiais e capacidade de selamento.