The effect of maxilla impacted canine positions on root resorption of adjacent teeth using cone-beam computed tomography imaging

Objective@#To determine the effect of the impacted position of the maxillary canine on the root resorption of the adjacent incisor using Cone-beam Computed Tomography (CBCT) imaging. @*Methods@#This was an analytic quantitative study. The research sample determined CBCT images of treatment patients at the Orthodontic Specialist Policlinic in Dental Hospital of Airlangga University over a three-year period and secondary data taken from Pramita Laboratory. CBCT photos that met the inclusion criteria, including mesially impacted canine or close to central or lateral incisors with completely formed anatomy were then analyzed. Multiple linear regression was used to determine x-axis, y-axis, z-axis position of the impacted canine on the severity of root resorption of the adjacent incisor, and the effect of impacted canines on all axes simultaneously on the severity of root resorption of the adjacent incisors. @*Results@#The position of the impacted canine in the x-axis and z-axis planes had a significant influence on the root resorption of the adjacent incisor. Meanwhile, impacted canine from the y-axis plane showed non-significant influence on the root resorption. @*Conclusion@#The position of the impacted canine when viewed in all planes of the tooth axis has a significant effect on the severity of root resorption of the adjacent incisor

Orthodontic treatment in traumatized permanent teeth: a systematic review / Tratamento ortodôntico em dentes permanentes traumatizados: uma revisão sistemática

Objective: to analyze, through literature review, the available literature on orthodontic treatment in traumatized permanent teeth. Methods: A literature search was performed in electronic databases (PubMed and SciELO) using the descriptors [tooth injuries] OR [injuries, teeth] OR [injury, teeth] OR [teeth injury] OR [injuries, tooth] OR [injury, tooth] OR [tooth injury] OR [teeth injuries] AND [orthodontics]. Observational studies and clinical trials were included, narrative reviews, laboratory and in vitro studies, case reports and series as well as articles that presented abstracts written in languages other than Portuguese, English and Spanish were excluded from the study. Two reviewers considered the eligibility, the risk of bias of the analyzed data and the qualitative synthesis of the studies included. A total of 1,322 references were found and 4 articles met all inclusion criteria and were included in the qualitative analysis. Some consequences like pulp necrosis and root resorption have been highlighted and trauma severity should be considered when orthodontically intervening in previously traumatized teeth. Final considerations: The traumatized teeth can be orthodontically treated as long as the time of tissue reorganization is respected, and the pull and periodontal conditions are followed up.(AU)

Objetivos: analisar, por meio de revisão de literatura, a respeito do tratamento ortodôntico em dentes permanentes traumatizados. Metodologia: Uma pesquisa bibliográfica foi realizada em bancos de dados eletrônicos (PubMed e SciELO) usando os descritores [tooth injuries] ou [injuries, teeth] ou [injury, teeth] ou [teeth injury] ou [injuries, tooth] ou [injury, tooth] ou [tooth injury] ou [teeth injuries] e [orthodontics]. Foram incluídos estudos observacionais e ensaios clínicos, revisões narrativas, estudos laboratoriais e in vitro, relatos de casos e séries, bem como artigos que apresentassem resumos redigidos em idiomas diferentes do português, inglês e espanhol foram excluídos do estudo. Dois revisores consideraram a elegibilidade, o risco de viés dos dados analisados e a síntese qualitativa dos estudos incluídos. Foram encontradas 1.322 referências e 4 artigos atenderam a todos os critérios de inclusão e foram incluídos na análise qualitativa. Algumas consequências como necrose pulpar e reabsorção radicular têm sido destacadas e a gravidade do trauma deve ser considerada na intervenção ortodôntica em dentes previamente traumatizados. Considerações finais: Os estudos incluídos nesta revisão sugerem que dentes traumatizados podem ser tratados ortodônticamente desde que respeitado o tempo de reorganização tecidual e acompanhadas as condições pulpares e periodontais.(AU)

Photobiomodulation therapy assisted orthodontic tooth movement: potential implications, challenges, and new perspectives / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Over the past decade, dramatic progress has been made in dental research areas involving laser therapy. The photobiomodulatory effect of laser light regulates the behavior of periodontal tissues and promotes damaged tissues to heal faster. Additionally, photobiomodulation therapy (PBMT), a non-invasive treatment, when applied in orthodontics, contributes to alleviating pain and reducing inflammation induced by orthodontic forces, along with improving tissue healing processes. Moreover, PBMT is attracting more attention as a possible approach to prevent the incidence of orthodontically induced inflammatory root resorption (OIIRR) during orthodontic treatment (OT) due to its capacity to modulate inflammatory, apoptotic, and anti-antioxidant responses. However, a systematic review revealed that PBMT has only a moderate grade of evidence-based effectiveness during orthodontic tooth movement (OTM) in relation to OIIRR, casting doubt on its beneficial effects. In PBMT-assisted orthodontics, delivering sufficient energy to the tooth root to achieve optimal stimulation is challenging due to the exponential attenuation of light penetration in periodontal tissues. The penetration of light to the root surface is another crucial unknown factor. Both the penetration depth and distribution of light in periodontal tissues are unknown. Thus, advanced approaches specific to orthodontic application of PBMT need to be established to overcome these limitations. This review explores possibilities for improving the application and effectiveness of PBMT during OTM. The aim was to investigate the current evidence related to the underlying mechanisms of action of PBMT on various periodontal tissues and cells, with a special focus on immunomodulatory effects during OTM.

Experimental study of subcutaneous adipose-derived stem cells inhibiting orthodontic root resorption / 中国修复重建外科杂志

OBJECTIVE@#To investigate the effect of human subcutaneous adipose-derived stem cells (hADSCs) local transplantation on orthodontically induced root resorption (OIRR) and provide theoretical and experimental basis for the clinical application of hADSCs to inhibit OIRR.@*METHODS@#Forty 8-week-old male Sprague Dawley rats were randomly divided into experimental group and control group, with 20 rats in each group, to establish the first molar mesial orthodontic tooth movement (OTM) model of rat right maxillary. The rats in the experimental group were injected with 25 μL of cell suspension containing 2.5×10 5 hADSCs on the 1st, 4th, 8th, and 12th day of modeling, while the rats in the control group were injected with 25 μL of PBS. The rat maxillary models were obtained before and after 7 and 14 days of force application, and 10 rats in each group were killed and sampled after 7 and 14 days of force application. The OTM distance was measured by stereomicroscope, the root morphology of the pressure side was observed by scanning electron microscope and the root resorption area ratio was measured. The root resorption and periodontal tissue remodeling of the pressure side were observed by HE staining and the root resorption index was calculated. The number of cementoclast and osteoclast in the periodontal tissue on the pressure side was counted by tartrate resistant acid phosphatase staining.@*RESULTS@#The TOM distance of both groups increased with the extension of the force application time, and there was no significant difference ( P<0.05). There was no significant difference in OTM distance between the experimental group and the control group after 7 and 14 days of force application ( P>0.05). Scanning electron microscope observation showed that small and shallow scattered resorption lacunae were observed on the root surface of the experimental group and the control group after 7 days of force application, and there was no significant difference in the root resorption area ratio between the two groups ( P>0.05); after 14 days of application, the root resorption lacunae deepened and became larger in both groups, and the root resorption area ratio in the experimental group was significantly lower than that in the control group ( P<0.05). The range and depth of root absorption in the experimental group were smaller and shallower than those in the control group, and the root absorption index in the experimental group was significantly lower than that in the control group after 14 days of force application ( P<0.05). The number of cementoclast in the experimental group was significantly lower than that in the control group after 7 and 14 days of force application ( P<0.05); the number of osteoclasts in the experimental group was significantly lower than that in the control group after 14 days of force application ( P<0.05).@*CONCLUSION@#Local transplantation of hADSCs may reduce the area and depth of root resorption by reducing the number of cementoclasts and osteoclasts during OTM in rats, thereby inhibiting orthodontic-derived root resorption.

Aspectos clínicos y forenses del color rosa de los dientes: reporte de un caso / Clinical and forensic aspects of the pink color of teeth: report of a case

La coloración rosa de los dientes puede originarse por diferentes factores. En el ámbito forense se ha descrito al fenómeno denominado post mortem pink teeth como un signo asociado a muertes violentas de etiología diversa. En la práctica clínica también es posible observar pacientes con dientes rosados, fre-cuentemente ocasionados por traumatismos o iatro-genia proveniente de ortodoncia, cuyo mecanismo de producción obedece a distintas etiopatogenias, destacándose las reabsorciones dentinarias inter-nas, cemento-dentinarias externas y calcificaciones dentinarias. El presente artículo expone el caso de un individuo adulto con antecedente de trauma óseo-dentario por accidente vial que, luego de un prolon-gado tiempo, asiste al Servicio de Urgencias Odon-tológicas y Orientación de Pacientes de la Facultad de Odontología de la Universidad de Buenos Aires, en donde se le detecta, a modo de hallazgo exploratorio, una ostensible coloración rosada en el canino infe-rior derecho. La situación motivó un pormenorizado abordaje clínico y radiográfico, indagando respecto a los probables factores que intervinieron en su ge-neración y desarrollo (AU)

The pink coloration of the teeth can be caused by dif-ferent factors. In the forensic field, the phenomenon called post mortem pink teeth has been described as a sign associated with violent deaths of various etiology. In clinical practice, it is also possible to ob-serve patients with pink teeth, frequently caused by trauma or iatrogenesis from orthodontics, whose production mechanism is due to different etiopatho-genesis, highlighting internal dentin resorption, ex-ternal cemento-dentinal resorption and dentin calci-fications. This article presents the case of an adult individual with a history of bone-dental trauma due to a road accident who, after a long time, attends the Dental Emergency and Patient Guidance Service of the Faculty of Dentistry of the University of Bue-nos Aires, where an ostensible pink coloration was detected in the lower right canine as an exploratory finding. The situation motivated a detailed clinical and radiographic approach, inquiring about the probable factors that intervened in its generation and development (AU)

RANKL+ senescent cells under mechanical stress: a therapeutic target for orthodontic root resorption using senolytics / 国际口腔科学杂志·英文版

In dentistry, orthodontic root resorption is a long-lasting issue with no effective treatment strategy, and its mechanisms, especially those related to senescent cells, remain largely unknown. Here, we used an orthodontic intrusion tooth movement model with an L-loop in rats to demonstrate that mechanical stress-induced senescent cells aggravate apical root resorption, which was prevented by administering senolytics (a dasatinib and quercetin cocktail). Our results indicated that cementoblasts and periodontal ligament cells underwent cellular senescence (p21+ or p16+) and strongly expressed receptor activator of nuclear factor-kappa B (RANKL) from day three, subsequently inducing tartrate-resistant acid phosphatase (TRAP)-positive odontoclasts and provoking apical root resorption. More p21+ senescent cells expressed RANKL than p16+ senescent cells. We observed only minor changes in the number of RANKL+ non-senescent cells, whereas RANKL+ senescent cells markedly increased from day seven. Intriguingly, we also found cathepsin K+p21+p16+ cells in the root resorption fossa, suggesting senescent odontoclasts. Oral administration of dasatinib and quercetin markedly reduced these senescent cells and TRAP+ cells, eventually alleviating root resorption. Altogether, these results unveil those aberrant stimuli in orthodontic intrusive tooth movement induced RANKL+ early senescent cells, which have a pivotal role in odontoclastogenesis and subsequent root resorption. These findings offer a new therapeutic target to prevent root resorption during orthodontic tooth movement.

Combined micro-apical surgery and vital pulp therapy in mandibular second molars with external root resorption caused by impacted teeth / 华西口腔医学杂志

OBJECTIVES@#This study aimed to establish a new treatment of the mandibular second molars with external root resorption caused by impacted teeth to preserve the affected teeth and their vital pulps.@*METHODS@#For mandibular second molars clinically diagnosed as external root resorption caused by impacted teeth, debridement and removal of the root at the resorption site via micro-apical surgery and direct capping of the pulp with bioactive material on the surface of the root amputation via vital pulp therapy were performed immediately after the impacted teeth were extracted.@*RESULTS@#The external root resorption of the affected tooth was ceased. It was asymptomatic with intact crown, normal pulp, periapical alveolar bone reconstruction, normal periodontal ligament, continuous bone sclerosis, and no periapical translucency in radiographic examination at the 1-year postoperative follow-up, thus showing good prognosis.@*CONCLUSIONS@#Simultaneous combination of micro-apical surgery and vital pulp therapy after extraction of impacted teeth could successfully preserve mandibular second molars with ERR caused by impacted teeth and their vital pulps.

Reabsorción dentinaria interna coronaria: informe de un caso clínico / Coronary internal dentine resorption: report of a clinical case

Objetivo: La reabsorción dentinaria interna es un pro- ceso causado por la actividad odontoclástica asociada princi- palmente a la inflamación pulpar crónica y/o traumatismos, y se caracteriza por la pérdida progresiva de tejido dentinario y la posible invasión al cemento. El presente informe describe el diagnóstico y tratamiento de un molar inferior que presentó un cuadro sintomático de reabsorción dentinaria interna. Caso clínico: Un paciente de 38 años fue derivado a la consulta por presentar una zona de reabsorción interna en un segundo molar inferior. Durante el examen clínico y ra- diográfico se tomó una radiografía preoperatoria periapical con radiovisiógrafo en la que se observó la presencia de un área compatible con el diagnóstico de reabsorción dentinaria interna, el que fue posteriormente confirmado por medio de una tomografía computada de haz cónico. La imagen de la lesión se presentó como una zona radiolúcida deformante de bordes nítidos, localizada a nivel de la cámara pulpar. El tra- tamiento consistió en la extirpación de la pulpa coronaria y de la instrumentación, desinfección y obturación de los conduc- tos radiculares y la cavidad de acceso. En el control clínico y radiográfico realizado luego de 3 años se observó que el paciente estaba asintomático y las estructuras perirradiculares se encontraban dentro de los límites normales. La observación histológica del material removido de la cámara pulpar reveló la presencia de un tejido granulomatoso con numerosos vasos sanguíneos y escasos focos micro hemorrágicos. Hasta el momento, el tratamiento endodóntico es el pro- cedimiento indicado para el tratamiento de la reabsorción dentinaria interna. Se destaca la importancia de la tomografía computada de haz cónico para el diagnóstico y tratamiento temprano de las reabsorciones dentinarias internas a efectos de contar con un pronóstico favorable (AU)

Aim: Internal dentine resorption is aprocess caused by odontoclastic activity, mainly associated with chronic pulpal inflammation and/or trauma, and it'scharacterized by a pro- gressive loss of dentine tissue and the possible invasion of the cementum. This report describes the diagnosis and treatment of a lower molar that presented a symptomatic case of inter- nal dentine resorption. Clinical case: A 38-years old patient was referred to the office because of presenting an area of internal resorption in a lower second molar. During clinical and radiographic exam- ination, a periapical preoperative radiograph with radiovisio- graph was taken, in which the presence of an area compatible with the diagnosis of internal dentine resorption was observed, which was later confirmed by a cone-beam computed tomog- raphy.The image of the lesion was presented as a deforming radiolucent area with sharp edges, located at pulp chamber level. Treatment consisted of the removal of the coronary pulp and the instrumentation, disinfection and filling of the root ca- nals and the access cavity. In the clinical and radiographic control carried out 3 years after procedure, it was observed that the patient was asymptomatic and the periradicular struc- tures were within normal limits. The histological observation of the removed material from the pulp chamber revealed the presence of a granulomatous tissue with numerous blood ves- sels and scarce micro hemorrhagic focus. Until now, the endodontic treatment is the indicated pro- cedure to treat internal dentine resorption. It is necessary to highlight the importance of the cone-beam computerized to- mography for the early diagnosis and treatment of internal dentine resorptions in order to have a favorable outlook (AU)

Directrices para el diagnóstico y tratamiento de Molares Retenidos / Guidelines for diagnosis and treatment of impacted molars

Los terceros molares son piezas dentarias correspondientes a la dentición permanente y se encuentran por detrás de los segundos molares. Erupcionan entre los 18 y 27 años aproximadamente, tienen variedad de formas, anomalías y disposición diversa. Normalmente se encuentran total o parcialmente retenidos en el hueso maxilar. La retención es muy frecuente y afecta aproximadamente al 75% de la población. La causa principal es por la falta de espacio dentro de la boca. La patología derivada de la retención de un tercer molar puede generar diferentes alteraciones: abscesos, sinusitis, reabsorción de las raíces de los dientes adyacentes, caries del molar retenido y/o del segundo molar, úlceras en la mucosa contigua, podrían generar quistes, ameloblastomas y ulceraciones leucoqueratósicas que pueden degenerar en carcinomas, alteraciones nerviosas o vasomotoras: dolores faciales, trismus, y parálisis facial ipsilateral. Las extracciones profilácticas de terceros molares asintomáticos están justificadas cuando los terceros molares se encuentran bajo prótesis removible que puede estimular su erupción, molares semierupcionados que pueden generar pericoronitis, caries o problemas periodontales; pacientes que van a ser sometidos a radioterapia; cuando el diente incluido interfiera en una cirugía ortognática. Si el molar retenido presenta sintomatología por parte del paciente está aconsejada su extracción quirúrgica.

The third molars are dental pieces corresponding to the permanent dentition and are located behind the second molars. They erupt between the ages of 18 and 27 approximately, have a variety of shapes, anomalies, and diverse dispositions. They are normally fully or partially retained in the maxillary bone. Retention is very frequent and affects approximately 75% of the population. The main cause is due to the lack of space inside the mouth. The pathology derived from the retention of a third molar can generate different alterations: abscesses, sinusitis, resorption of the roots of adjacent teeth, caries of the retained molar and/or second molar, ulcers in the contiguous mucosa, could generate cysts, ameloblastomas and leukokeratotic ulcerations that can degenerate into carcinomas, nervous or vasomotor disorders: facial pain, trismus, and ipsilateral facial paralysis. Prophylactic extractions of asymptomatic third molars are justified when the third molars are under removable prosthesis that can stimulate their eruption, semi-erupted molars that can generate pericoronitis, caries or periodontal problems; patients who are going to undergo radiotherapy; when the included tooth interferes with orthognathic surgery. If the retained molar presents symptoms on the part of the patient, its surgical extraction is recommended.

An unusual repair of perforating internal inflammatory root resorption; a case report of endodontic treatment

Internal inflammatory root resorption (IIRR) can occur as a serious complication of dental trauma which leads to progressive loss of the root structure. An early diagnosis could influence the therapeutic approach, but endodontic treatment becomes a challenge with a doubtful prognosis. The present report described an unusual clinical presentation of an IIRR with perforation resulting from a trauma four years previous. A 15-year-old female patient was presented to our service with pain in the maxillary incisor region. Intraoral radiography revealed a large radioloucent area compatible with IIRR, communicating with the periodontium in the middle third on the distal root face of the right central incisor. The root canal of the right central incisor was chemo-mechanically prepared. The calcium hydroxide (CH) intracanal medication was used and renewed periodically four times. The root canal was filled only in the cervical region to the level of resorption by the inverted gutta-percha cone technique. Clinically and radiographically, all follow-up examinations revealed an asymptomatic tooth, evidencing periapical tissue repair and new bone formation. The tooth remained asymptomatic 3 years afterwards. The present case report supports the idea of executing satisfactory intracanal decontamination by chemo-mechanical preparation, thus creating a favourable environment for tissue repair.

Root resorption pattern in panoramic radiographs of pediatric patients with unilateral posterior crossbite: a cross-sectional and retrospective study / Patrón de reabsorción radicular en radiografías panorámicas de pacientes pediátricos con mordida cruzada posterior unilateral: estudio transversal y retrospectivo

SUMMARY: temporary mandibular molars in panoramic radiographs of pediatric patients with unilateral posterior crossbite (UPCB). This cross-sectional and retrospective study analyzed 114 orthopantomograms of patients between 6 - 9 years of age with unilateral posterior crossbite diagnosis. The first and second mandibular molars were analyzed. Their root resorption stage was typified, and the root lengths were measured; to later compare the data obtained depending on the malocclusion side. 86.4 % of molars showed a linear resorption pattern, and atypical resorption prevalence in patients with UPCB was 13.5 %. The total length average of the first molars on the side of the malocclusion was 8.20 mm, while the contralateral exhibited a mean of 9.29 mm. Lastly, the second molars had a mean length of 11.12 mm in crossbite side and 12.30 mm in the normal occlusion side. UPCB could affect physiological resorption by observing a resorption alteration in those mandibular molars located on the malocclusion side.

RESUMEN: El trabajo de este estudio se realizó en molares mandibulares temporales en radiografías panorámicas de pacientes pediátricos con mordida cruzada posterior unilateral (MCPU). Este estudio transversal y retrospectivo analizó 114 ortopantomografías de pacientes entre 6 - 9 años de edad con diagnóstico de mordida cruzada posterior unilateral. Se analizaron los primeros y segundos molares mandibulares. Se tipificó su estado de reabsorción radicular y se midió la longitud de las raíces; para luego comparar los datos obtenidos según el lado de la maloclusión. El 86,4 % de los molares mostró un patrón de reabsorción lineal y la prevalencia de reabsorción atípica en pacientes con MCPU fue del 13,5 %. El promedio de longitud total de los primeros molares del lado de la maloclusión fue de 8,20 mm, mientras que el contralateral exhibió una media de 9,29 mm. Por último, los segundos molares tenían una longitud media de 11,12 mm en el lado de mordida cruzada y de 12,30 mm en el lado de oclusión normal. La MCPU podría afectar la reabsorción fisiológica al observar una alteración de la reabsorción en aquellos molares mandibulares ubicados en el lado de la maloclusión.

In Vivo Detection of External Apical Root Resorption Induced by Apical Periodontitis Using Periapical Radiography and Cone-Beam Computed Tomography

Abstract Objective: To compare the accuracy of periapical radiography (PR) and cone-beam computed tomography (CBCT) for the detection of external apical root resorption (EARR) due to root canal contamination. Material and Methods: Dog's teeth with experimentally induced root resorption due to root canal contamination underwent or not root canal treatment (n=62). True positives (TP), false positives (FP), true negatives (TN), and false negatives (FN) in PR and CBCT diagnoses were determined using histopathologic findings as the gold standard. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and diagnostic accuracy (TP + TN) in the diagnosis of EARR were calculated. Data were compared using chi-squared test (α=0.05). Results: EARR was detected in 35% of roots by PR, in 47% by CBCT, and in 50% of the roots by microscopy (p=0.03 PR versus microscopy; p=0.67 CBCT versus microscopy). Overall, CBCT produced more accurate diagnoses than PR (p=0.008). PR and CBCT allowed the identification of large resorption in 100% of the cases and showed the same accuracy. However, for small resorptions, PR showed an accuracy of 0.83, whereas CBCT showed an accuracy of 0.96 (p=0.003). Conclusion: Cone-beam computed tomography showed higher accuracy in detecting external apical root resorption of endodontic origin.

Quantitative Assessment of Dentine Sialophosphoprotein, Aspartate Aminotransferase and Lactate Dehydrogenase in Gingival Crevicular Fluid of Teeth with Root Resorption

ABSTRACT@#Root resorption is a shortening of root dentine which occurs physiologically in deciduous teeth. The present study aimed to quantify dentine sialophosphoprotein (DSPP), aspartate aminotransferase (AST) and lactate dehydrogenase (LDH) in gingival crevicular fluid (GCF) during the physiological process of root resorption of deciduous teeth. A cross-sectional study was conducted with 25 children aged between 4 and 10 years old. GCF was collected from the gingival sulcus using periopaper strips from the upper first deciduous molar (n = 45). The samples were divided equally into three groups, no resorption (R0), moderate resorption (RM) and severe resorption (RS), based on the existing radiographs taken. The GCF samples were then analysed using an enzyme-linked immunosorbent assay (ELISA) kit to determine the DSPP concentration levels and BioAssays System kit for AST and LDH. One-way ANOVA was used to determine the statistical differences between the means of the DSPP, AST and LDH concentration level in the three groups. A difference was considered significant when p < 0.05. High concentration levels of DSPP were significantly noted in RS (p < 0.05), compared to RM and R0. AST also portrayed significant high activity level (p < 0.05) similar to DSPP but LDH showed no significant changes between groups (p > 0.05). The high quantification of DSPP and AST levels in the severe and moderately resorbed roots indicated the potential use of this protein as a biomarker for detecting moderate-severe stages of root resorption.

Etiology and pathogenesis of internal root resorption / 中华口腔医学杂志

Internal root resorption is a pathologic phenomenon with a characterization of the intraradicular dentin destruction due to the abnormal activities of odontoclasts. With its insidious pathology, internal root resorption can progress to a great extent before its clinical detection. The etiology and natural history of internal root resorption are uncertain and the associated key molecular pathogenesis have not been understood completely. The resorption is usually initiated by a stimulus with the loss of the protective predentin and progressed by the continuous stimuli of pulp infection. Various factors including trauma, chronic inflammation of the pulp, pulpotomy and tooth transplantation have been proposed for the occurrence of internal root resorption. The present paper reviews the etiology and pathogenesis of internal root resorption and provides guidance for the early intervention in the clinical practice.

Diagnóstico de reabsorção radicular: influência da resolução espacial de captura de imagens digitais periapicais / Root resorption diagnostic: influence of periapical digital image scanning

Introdução: a detecção da reabsorção da raiz dentária é realizada por meio de exames de imagens, pois frequentemente não apresenta sinal e sintoma clínicos. Dentre os exames de imagem disponíveis, o exame radiográfico periapical, é indicado para diagnóstico, prognóstico e acompanhamento da reabsorção radicular. Objetivo: o estudo tem como objetivo investigar a relação de diferentes resoluções espaciais com o diagnóstico de reabsorção radicular. Metodologia: foram realizados desgastes simulando reabsorção externa no terço apical e vestibular de 15 (quinze) incisivos inferiores, radiografados em crânio seco, antes e depois do desgaste. A técnica radiográfica foi realizada utilizando o sistema VistaScan (Durr Dental, Bietigheim-Bissingen, Germany), aparelho CS 2200 (Carestream Dental LLC, Atlanta-GA, USA) usando tempo de exposição de 0,15 segundos e escaneadas sob diferentes protocolos de resolução espacial, a saber, 20 pares de linhas por milímetro (pl/mm) e 40 pl/mm. Posteriormente dois avaliadores experientes fizeram análises das referidas imagens sem conhecimento prévio da resolução de escaneamento. Resultados: 75% das radiografias realizadas com 20 pl/mm foram classificadas como excelentes pelos avaliadores, contra 33% com 40 pl/mm, estatisticamente significativa. Discussão: ao avaliar a reabsorção radicular, obteve-se uma acurácia diagnóstica igual para os dois protocolos sem distinção, estatisticamente significativa, entre localização ou profundidade. Conclusão: tendo em vista que para os examinadores imagens com 20 pl/mm foram satisfatórias, com percentual de qualidade maior quando comparado a imagens obtidas com 40 pl/ mm, este estudo indica o emprego de imagens com 20 pl/mm para avaliação inicial de suspeita de reabsorções nas raízes dentárias.

Introduction: the detection of tooth root resorption is carried out by means of imaging tests, as it often does not present a clinical sign and symptom. Among the imaging tests available, the periapical radiographic examination is indicated for diagnosis, prognosis and monitoring of root resorption. Objective: the study aims to investigate the relationship of different spatial resolutions in the diagnosis of root resorption. Methods: Artificial external root resorptions were simulated using burs by drilling to the entire depth in different locations at the apical and buccal thirds of 15 (fifteen) lower incisors were worn, radiographed on a dry skull, before and after wear. The radiographic technique was performed using the VistaScan system (Durr Dental, Bietigheim-Bissingen, Germany), CS 2200 device (Carestream Dental LLC, Atlanta-GA, USA) using an exposure time of 0.15 seconds and scanned under different resolutions protocols, namely, 20 pairs of lines per millimeters (pl/mm) and 40 pl/mm. Subsequently, two experienced evaluators performed analyzes of these images without prior knowledge of the scanning resolution. Results: seventy-five percent of the radiographs taken at 20 pl/mm were rated as excellent by the evaluators, against 33% at 40 pl/mm, a statistically significant difference. Discussion: When assessing root resorption, a similar diagnostic accuracy was obtained for the two protocols without a statistically significant distinction between location or depth. Conclusions: Considering that for examiners images with 20 pl/mm were satisfactory, with a percentage of quality greater than 40 pl/mm, this study indicates the use of 20 pl/mm for initial evaluation of suspected root resorption.

Endodoncia y ortodoncia. Parte 2: casos clínicos / Endodontics and orthodontics. Part 2: clinical cases

Objetivo: Describir el tratamiento endodóncico de cuatro casos clínicos de reabsorción radicular desarrollada durante o tras un tratamiento ortodóncico. Casos clínicos: Después de la preparación y la desinfección de los conductos radiculares, estos fueron obturados por un tiempo prudencial con una medicación intraconducto de hidróxido de calcio, que luego fue reemplazada por MTA. Luego de un período de entre uno y cuatro años, según el caso, los tratamientos fueron evaluados clínica y radiográficamente. Los dientes que debieron ser extraídos fueron analizados histológicamente. Según la evolución clínica y radiográfica de los casos presentados, el uso inicial de hidróxido de calcio y su posterior reemplazo por MTA parecería ser un protocolo adecuado para completar el proceso de reparación de los tejidos apicales y perirradiculares en casos de reabsorciones radiculares provocadas por fuerzas ortodóncicas excesivas. Las enfermedades sistémicas deben ser tenidas en cuenta para la elección de la terapéutica (AU)

Aim: To describe the endodontic treatment of four clinical cases of permanent teeth suffering root resorption during or after orthodontic treatment. Clinical cases: Four clinical cases of permanent teeth with root resorption were endodontically treated. After the root canals were prepared and disinfected, they were medicated with calcium hydroxide. After an appropriate observation period, the canals were finally filled with MTA. The treatment outcomes were clinically and radiographically assessed at an interval between one to four years according to the clinical case. The histological findings of teeth that required extraction was also described. Our clinical and radiographic observations suggest that a temporary filling with calcium hydroxide and further obturation with MTA can provide a favorable intracanal environment for apical and periradicular tissue reparation. The clinician needs a full medical history to be aware of the systemic diseases in patients with root resorption that will be of importance for the proper selection of treatment (AU)

Reabsorção radicular interna de incisivos superiores permanentes tratados endodonticamente / Internal radicular reabsorption of endodontically treated permanent upper incisives

As reabsorções radiculares são classificadas em interna e externa e um correto diagnóstico é fundamental para o sucesso no tratamento e é de suma importância que a resolução clínica seja feita precocemente para que se tenha um prognóstico clínico favorável. Reabsorção interna não é comum em dentes permanentes, e seu processo se caracteriza por um aumento do canal radicular de forma oval. O presente estudo teve como objetivos demonstrar e descrever através de um relato de prontuário o tratamento de reabsorção radicular interna de incisivos superiores permanentes. Através da seleção de uma paciente pela disciplina de Triagem da clínica odontológica do Centro Universitário da Serra Gaúcha, a qual apresentou alterações radiográficas compatíveis com reabsorção radicular interna inflamatória na região de dois incisivos superiores permanentes, com lesão periapical estabelecida em ambos, concluiu-se o tratamento para então gerar este estudo do tipo retrospectivo observacional. A reabsorção quando não tratada pode avançar e envolver estruturas além do tecido conjuntivo inflamado e a lesão pode avançar em direção apical. Após estabelecido o diagnóstico, iniciou-se os tratamentos endodônticos dos elementos utilizando hidróxido de cálcio como medicação intracanal, após as trocas de medicações as reabsorções foram controladas e então, as obturações dos canais foram realizadas, buscando um preenchimento adequado para o caso. A reabsorção radicular interna inflamatória causa danos irreversíveis, mas seu processo foi controlado através de terapia endodôntica. Este desempenho é considerado uma patologia, e pode comprometer qualquer extensão da raiz, é comum que os casos permaneçam assintomáticos, portanto, deve ser tratado o mais breve possível assim que descobertos para evitar sua progressão, e consequentemente danos maiores(AU)

Root resorption is classified as either internal or external, and a correct diagnosis is essential for successful treatment. Internal resorption is not common in permanent teeth, and its process is characterized by an enlarged oval root canal. The present study aims to demonstrate and describe, through a medical record, the treatment of internal root resorption of permanent upper incisors. A patient was selected from the Triage Course of the Dental Clinic (Centro Universitário da Serra Gaúcha) who presented radiographic changes associated with inflammatory internal root resorption in two permanente upper incisors, with a periapical lesion established in both and a treatment was then carried out in order to generate this retrospective observational study. Resorption when left untreated can progress and involve structures beyond the inflamed connective tissue and the lesion can advance in the apical direction. After the diagnosis was confirmed, endodontic treatments were initiated using calcium hydroxide as an intracanal medication. After changing the medication, the resorption was controlled and then the canal fillings were performed, seeking an adequate filling for the case. Inflammatory internal root resorption causes irreversible damage, but its process has been controlled through endodontic therapy. This performance is considered a pathology, and can compromise any extension of the root, it is common for the cases to remain asymptomatic, therefore, it should be treated as soon as it's discovered to prevent its progression, and consequently greater damage(AU)

Plasma rico en fibrina e injerto conectivo en la instalación de un implante dental / Fibrin-rich plasma and connective tissue graft in dental implant installation

Introducción: Combinar tratamientos regenerativos con injertos de tejido blando impide que el tejido periimplantario se atrofie y altere la estética. Los resultados de esta combinación son discutidos en la literatura actual cuando se trata de implantes inmediatos. Objetivo: Describir el tratamiento regenerativo combinando plasma rico en fibrina e injerto conectivo en la instalación de un implante dental en el sector anterosuperior. Presentación del caso: El paciente fue un varón de 40 años de edad sin antecedentes de enfermedades sistémicas, con trauma facial. Al examen clínico se observó una corona de porcelana fracturada a nivel cervical vestibular, secreción purulenta en proceso de cicatrización y contorno gingival alterado. En el examen radiográfico se evidenció una lesión periapical con aparente reabsorción radicular. Se extrajo el diente, se colocó plasma rico en fibrina para mejorar la cicatrización, se esperaron 6 semanas y se colocó un implante. Al cabo de 4 meses se realizó la segunda fase con un injerto de tejido conectivo y colocación del cicatrizal, se esperaron dos semanas y se colocó una corona de porcelana. Conclusiones: En el presente caso, la combinación de plasma rico en fibrina e injerto conectivo favoreció el aspecto estético periimplantario sin evidenciarse complicaciones durante el posoperatorio(AU)

Introduction: Combining regenerative treatments with soft tissue grafts prevents atrophy of the peri-implant tissue and alterations in esthetics. The results of this combination are discussed in the current literature. Objective: To describe the regenerative treatment, combining Fibrin-rich plasma and connective tissue graft in the installation of a dental implant in the upper anterior sector. Case presentation: Forty-year-old male patient with facial trauma. He has no history of systemic diseases. On clinical examination, a fractured porcelain crown was found at the vestibular cervical level. There was purulent discharge in the healing process and altered gingival contour. Radiographic examination revealed a periapical lesion with apparent root resorption. The tooth was extracted; fibrin-rich plasma was placed to improve healing. Six weeks after, an implant was placed. After the first four months, the second phase was performed with a connective tissue graft and placement of the scar tissue; two weeks after, a porcelain crown was placed. Conclusions: In the present case, the combination of Fibrin-rich plasma and connective tissue graft favored the peri-implant esthetic appearance without evidence of complications during the postoperative period(AU)

Influence of different types of rapid maxillary expansion on root resorption: a systematic review / 华西口腔医学杂志

OBJECTIVES@#This study aimed to assess the influence of different types of rapid maxillary expansion on root resorption (RR).@*METHODS@#Literature searches were carried out electronically in five English and two Chinese databases. Randomized controlled trials (RCTs), controlled clinical trials (CCTs), cohort studies, and case-control studies were included. The data were extracted by three authors. The risk of bias in the RCTs and nonrandomized studies were assessed in accordance with corresponding scales.@*RESULTS@#Among the 400 articles identified, seven were included for the final analysis. Three studies were graded as high value of evidence, while two and another two studies were graded as moderate value and low value, respectively. According to the available evidence, the tooth-borne maxillary expansion caused more obvious RR of anchorage teeth than the bone-borne one. In addition, the Haas-type palatal acrylic pads could not effectively reduce the degree of RR. The difference in the design of the retainer between the tooth-borne maxillary expansion (the use of a band or wire framework to connect the anchorage tooth) did not cause the difference in the incidence and degree of RR.@*CONCLUSIONS@#Clinical evidence suggested that bone-borne maxillary expansion may decrease the amount of RR, while the amounts of resorption did not significantly differ between Haas and Hyrax and between different retainer types of Hyrax.

Intrusion of posterior teeth using miniplates: intrusive mechanics is not the same as intrusion force

ABSTRACT Objective: Biologically explain some of the bone mechanisms involved in the intrusion, or intrusive effect, of teeth submitted to skeletal open bite correction using four miniplates. Methods: The results of dental intrusion were measured and compared in 3D reconstructions of cone beam computed tomography scans taken before and after treatment of 20 patients with skeletal open bite, aged between 18 and 59 years. Results: The results allow deducing that the compression and traction forces biologically promoted deformation or deflection of the osteocyte network that controls bone design, and these effects involved the external and internal surfaces of the bone, with the formation of new layers, including the cervical portion of the alveolar bone crest. This helps understanding how dental intrusion occurs in intrusive mechanics, whose forces are of inclination rather than intrusion. The root resorptions caused by the use of miniplates were insignificant, due to the more homogeneous distribution of forces in the several teeth simultaneously involved. Conclusion: Imaging studies in CT scans tend to capture in details the subperiosteal and endosteal phenomena of dental intrusion - before and after the application of intrusive mechanics -, in the form of a set of modifications called dental intrusion or intrusive effect .

RESUMO Objetivo: Explicar, biologicamente, alguns dos mecanismos ósseos envolvidos na intrusão, ou efeito intrusivo, de dentes submetidos à correção da mordida aberta esquelética por meio do uso de quatro miniplacas. Métodos: Foram mensurados, em reconstruções 3D de tomografias computadorizadas de feixe cônico, os resultados da intrusão dentária, comparando-se o antes e o depois em 20 pacientes com mordida aberta esquelética, com idades entre 18 e 59 anos. Resultados: Os resultados permitem deduzir que as forças de compressão e de tração promovem, biologicamente, deformação ou deflexão da rede osteocítica controladora do design ósseo, e esses efeitos envolvem as superfícies externas e internas do osso, com formação de novas camadas, incluindo a parte cervical da crista óssea alveolar. Isso ajuda a compreender como ocorre a intrusão dentária nas mecânicas intrusivas cujas forças são de inclinação, e não de intrusão. As reabsorções radiculares promovidas pelo uso de miniplacas são insignificantes, em função da distribuição mais homogênea das forças nos vários dentes simultaneamente envolvidos. Conclusão: Os estudos imagiológicos tendem a captar, nas tomografias, cada vez mais detalhadamente os fenômenos subperiosteais e endosteais da intrusão dentária nos pacientes - antes e depois da aplicação das mecânicas intrusivas -, na forma de um conjunto de modificações que se chama intrusão dentária ou efeito intrusivo.