Microcomputed tomography analysis of curved root canal preparation when coronal flaring and glide path files used with heat-treated nickel titanium rotary files.

The objective was to evaluate the effect of glide path and coronal flaring on the dentin volume removal and percentage of touched walls in curved canals using two heat-treated rotary files. The mesiobuccal canal of forty-eight, randomly selected, extracted mandibular molars was divided into two groups of 24 each, according to the type of instrument used (RACE EVO and EdgeSequel rotary files). Each group was further divided into three subgroups; Group (A): Control using one file shaped to 04/30, Group (B) with a glide path (EdgeGlidePath (EGP)), and Group (C): with a glide path and coronal flaring (EGP and EdgeTaper Platinum (ETP) SX file respectively). The root canals were then instrumented using the assigned instruments. The assessment was carried out using micro-CT. The comparison of the mean values of the tested groups about dentin volume removal and percentage of untouched walls did not reach statistical significance (p<0.05). Glide path and coronal flaring had an insignificant effect on the dentin volume removal and percentage of untouched walls in curved canals.

Finite element study of the fatigue behaviour of nickel-titanium endodontic files utilised with pecking motion technique.

The purpose of the study is to evaluate the influence of the pecking motion (reciprocal axial motion) surgical technique on the durability behaviour of the Nickel-Titanium endodontic files using Finite Element Analysis (FEA). A commonly used endodontic file, ProTaper Universal F2, is selected for the study. Root canal treatment procedure is simulated on a test-bench (simulated root canal) proposed by G. Gambarini for cyclic fatigue loading of endodontic files with and without the pecking motion via FEA. The hysteresis energy density is used as evaluation criteria for low cycle fatigue life estimation of Shape Memory Alloy files. In an additional study, the root canal treatment procedure is also simulated for an FEA model of a molar tooth with significant root canal curvature to understand the influence of the realistic curvature of a root canal on the fatigue behaviour of endodontic files. For the simulated root canal, analysis accurately predicts the endodontic file's failure location, and fatigue life estimation based on the hysteresis energy density is shown to increase significantly with the introduction of the pecking motion, an observation confirmed by reported experimental results. Molar tooth simulations reveal greater file fatigue resistance than in simulated root canals, confirming the pecking motion's efficacy in enhancing file durability, even in real root canal conditions. Simulations indicate that the pecking motion technique increases the fatigue life of endodontic files for simulated as well as real root canals and the hysteresis energy is confirmed as an acceptable parameter to quantify fatigue life of Nickel-Titanium endodontic files.

Evaluating In Vitro Performance of a Novel Stainless Steel Rotary System (Gentlefile) Based on Debris Extrusion and Instrumentation Time.

The new Gentlefile (GF) system, made of stainless steel and developed by MedicNRG in Kibbutz Afikim, Israel, claims to have advantages over traditional nickel-titanium files. However, research has shown that nickel-titanium files are mechanically superior due to their increased flexibility, cutting efficiency, and ability to maintain canal anatomy with less risk of procedural errors. This study compared the amount of debris extrusion and the time required for root canal instrumentation using GF versus the nickel-titanium ProTaper Universal (PTU) system and a manual step-back (MSB) stainless steel technique. This in vitro experimental study utilized 66 extracted human single-canal mandibular premolars with mature apices and root curvature of less than 10 degrees. The teeth were randomly divided into three groups (n = 22) and standardized for working length before being placed in preweighed vials. Group 1 was instrumented with PTU, Group 2 with GF, and Group 3 with the MSB technique. Extruded debris was collected in the vials, dried in an incubator, and weighed using the same scale. The change in weight indicates the debris amount. Instrumentation time was recorded using a stopwatch. The normal distribution of data was assessed using the Kolmogorov-Smirnov test. The groups were then compared regarding the amount of extruded debris and instrumentation time using the Kruskal-Wallis test and one-way ANOVA, followed by the Games-Howell test, respectively (alpha = 0.05). No significant difference in apical debris extrusion was found among the three groups (P > 0.05). However, a significant difference in instrumentation time was detected between the groups (P < 0.05). MSB instrumentation took significantly longer than both the PTU (P = 0.001) and GF (P = 0.001) systems. The GF system did not demonstrate reduced apical debris extrusion or faster instrumentation time compared to PTU. MSB had the longest instrumentation time compared to the other techniques.

Guided endodontics versus conventional access cavity preparation: an ex vivo comparative study of substance loss.

BACKGROUND: To compare the outcomes of conventional access cavity preparation (CONV) versus guided endodontics (GE) for access cavity preparation in anterior teeth with pulp canal calcification (PCC) regarding root canal detection, substance loss, procedural time, and need for additional radiographs. METHODS: Extracted, sound human teeth with PCC (n = 108) were matched in pairs, divided into two groups and used to produce 18 models. An independent endodontist and a general dentist performed access cavity preparation under simulated clinical conditions on nine models each (54 teeth). The endodontist used the conventional technique and the general dentist GE. Time needed to access the root canals and the number of additional radiographs were recorded. Pre- and postoperative cone-beam computed tomography scans were obtained to measure substance loss. Statistical significance was tested by examining the overlap of 95% confidence intervals (CIs) between the groups. RESULTS: All root canals were successfully accessed by both methods. There were no significant differences in substance loss (CI: CONV 15.9-29.6 mm3 vs. GE 17.6-27.5mm3) or procedural time (CI: CONV 163.3-248.5 s vs. GE 231.9-326.8 s). However, 31 additional radiographs were required for GE compared to none for CONV. CONCLUSIONS: For access cavity preparation in teeth with PCC, both CONV by a specialist and GE by a general dentist produce good results in terms of substance loss and time requirements.

Apically extruded debris, canal transportation, and shaping ability of nickel-titanium instruments on contracted endodontic cavities in molar teeth.

PURPOSE: Apically extruded debris, canal transportation and shaping ability were compared between contracted endodontic cavities (CECs) and traditional endodontic cavities (TECs) after instrumentation with XP-endo Shaper (XPS), ProTaper Gold (PTG), ProTaper for hand-use (HPT) and Hero Shaper. METHODS: The CECs or TECs groups were sub-divided into 24 groups according to root canal morphology and nickel-titanium (Ni-Ti) instruments. The weight of apically extruded debris was calculated using the Myers and Montgomery model. Pre- and postoperative images of teeth were scanned using micro-CT and the three-dimensional models were constructed and compared. RESULTS: Under CECs or TECs, XPS and PTG produced less apical debris and formed less canal transportation than HPT and Hero Shaper (P < 0.05). XPS group under CECs extruded less apical debris than that under TCEs for round canals with curvature of 20°-35° (P < 0.05). The centering ratios of four tested instruments were higher under TECs than those under CECs (P < 0.05). The HPT and Hero Shaper had more transportation under CECs than that under TCEs (P < 0.05). No statistical difference was found regarding shaping ability among all the groups. CONCLUSION: Under CECs, XPS preserves the original root canal anatomy, meanwhile it produces less apical debris than the other instruments.

Evaluation of apical extrusion of debris and centering ability in different nickel-titanium files during curved root canal preparation.

BACKGROUND: Curved root canals lead to difficulties in cleaning, shaping and filling the root canal system. Apical extrusion of debris and root canal transportation are important factors causing postoperative complications. In clinical practice, commonly selected instruments include multifile NiTi systems, such as M3-Pro PLUS (M3-PRO), Orodeka Plex 2.0 (ODP), Rotate (ROT), and Protaper Gold (PTG), as well as single-file NiTi systems, such as M3-L Platinum 2019 (M3L), Waveone Gold (WOG), and Reciproc Blue (RCB). This study aimed to comprehensively evaluate the differences in the apical extrusion of debris and centering ability of the above NiTi files. METHODS: Seventy 3D-printed resin teeth were used (n = 10). The apically extruded debris was collected in a preweighed centrifuge tube. The resin teeth with or without root canal preparation were cut into separate cross sections at 1 mm, 3 mm, 5 mm, and 7 mm away from the root apex, and then the root canal transportation and centering ratio of each cross section were calculated. RESULTS: Apical extrusion of debris was highest in RCB but lowest in OD-P (P < 0.05). Root call deviation was lowest in ROT at the 3 mm level, in PTG at the 5 mm level, and in PTG and ROT at the 7 mm level (P < 0.05). The centering ratio of NiTi files was highest in the RCB group at the 3 mm level, in the PTG group at the 5 mm level, in the ROT group at the 7 mm level (P < 0.05). CONCLUSIONS: For NiTi files with the same system, the cross-sectional design is the greatest factor affecting the extrusion of debris, and motion mode is the second. In addition, the multifile system could reduce the degree of root canal transportation.

CBCT imaging and root canal treatment for taurodontism in mandibular second molar - A case report and literature review.

The mandibular second molar exhibits a wide range of intricate root canal variations, which can present challenges and difficulties in achieving successful root canal treatment. This report focuses on two specific cases involving a root canal variation in a typical taurodontism of the mandibular second molar. To provide a comprehensive analysis and illustration of the anatomical structure of intraoral taurodontism and the important considerations for root canal treatment, we utilized advanced imaging techniques such as cone beam computed tomography (CBCT) and a dental microscope. By combining these tools, we were able to gain a deeper understanding of the complex root canal system and make informed decisions during the treatment process.

Abordagem multidisciplinar no tratamento de incisivo lateral com fratura oblíqua e lesão periapical: relato de caso clínico / Multidisciplinary approach in the treatment of lateral incisor with oblique fracture and periapical injury: clinical case report

Casos de fraturas dentárias oblíquas muitas vezes possuem um prognóstico desfavorável, geralmente com indicação da extração do elemento dental. O presente artigo visou relatar o tratamento do caso clínico de um paciente do sexo masculino, 12 anos, que compareceu à Unidade de Saúde Bucal do Hospital Universitário de Brasília com encaminhamento de extração do dente 12, apresentando fratura oblíqua que se estendia subgengivalmente na face vestibular. O trauma havia ocorrido há três anos e o paciente havia sido submetido a diversas intervenções endodônticas, apresentando no momento da consulta inicial por nossa equipe uma lesão periapical extensa. Após a realização da anamnese, exame clínico e radiográfico, foi adotada uma abordagem multidisciplinar conservadora com a manutenção do dente e a realização da enucleação da lesão periapical por meio de intervenção cirúrgica e posterior reabilitação. Em uma mesma sessão, foi realizada a obturação do conduto com cone de guta percha e cimento sealer 26 e a cirurgia parendodôntica juntamente com a apicoplastia. Uma semana após a intervenção cirúrgica foi realizada restauração classe IV com resina composta baseada no enceramento dos modelos de diagnóstico montados em articulador. Com base em uma avaliação criteriosa e multidisciplinar, foi possível adotar uma abordagem conservadora no caso em questão, com a manutenção e reabilitação de um dente permanente em um paciente jovem, evitando a indicação de exodontia(AU)

Cases of oblique dental fractures often have an unfavorable prognosis, usually with the indication of extraction of the dental element. The present article aimed to report the treatment of the clinical case of a 12-year-old male patient, who attended the Oral Health Unit of the Hospital Universitário de Brasília with a referral for extraction of tooth 7, presenting an oblique fracture that extended subgingivally on the labial surface. The trauma had occurred three years ago and the patient had undergone several endodontic interventions, presenting an extensive periapical lesion at the time of the initial consultation by our team. After anamnesis, clinical and radiographic examination, a conservative multidisciplinar approach was adopted with the maintenance of the tooth and the enucleation of the periapical lesion through surgical intervention and subsequente rehabilitation. In the same session, the conduit was filled with gutta-percha cone and sealer cement 26 and parendodontic surgery was performed together with apicoplasty. One week after the surgical intervention, class IV restoration was performed with composite resin based on the waxing of the diagnostic models mounted on an articulator. Based on a careful and multidisciplinary evaluation, it was possible to adopt a conservative approach in the case in question, with the maintenance and rehabilitation of a permanent tooth in a young patient, avoiding the indication of extraction(AU)

DETERMINATION OF CYCLIC FATIGUE OF A NICKEL-TITANIUM COXO SC PRO FILE USING A SIMULATION ENDODONTIC UNIT.

The use of nickel-titanium instruments during endodontic treatment ensures high-quality treatment of root canals. However, during instrumentation in the curved root canals of nickel-titanium instruments experience cyclic loading, which leads to their breakage. The splinter of the tool in the root canal makes it difficult for high-quality processing and obturation of the root canal, which is a very urgent problem. To carry out instrumental processing in canals with various anatomical and topographic features, the files must have phenomenal flexibility, lack of straightening of the canal, and have a safe non-aggressive tip. And for this reason, one of the most popular nickel-titanium COXO SC PRO tools was selected as a study, which, according to the manufacturer, have all the listed properties. The aim of the study is to determine the limit of resistance to cyclic loading and signs of breakage of the nickel-titanium endodontic instrument COXO SC PRO. Sterilization treatment, which is based on autoclaving, significantly reduces the strength characteristics of COXO SC PRO nickel-titanium files, which limits the use of these tools to one-time use without the risk of their breakage.

Endodoncia guiada Para el manejo de Canales Obliterados, Reporte de Caso / Guided Endodontic Treatment for the Management of Obliterated Pulp Canals. A Case Report

RESUMEN: El objetivo: de este reporte es presentar el tratamiento endodóntico de un diente ante-rior con obliteración del canal radicular, con la ayuda de la endodoncia guiada. Paciente masculino sin antecedentes médicos relevante, y en tratamiento ortodóntico. Diente 2.1 con historia de traumatismo dento-alveaolar y presencia de dolor a la percusión. En la TCHC se observa obliteración total del canal radicular en el tercio cervical y medio y un área de radiolucidez apical. Diagnóstico: Periodontitis apical Sintomática. Tratamiento: Terapia de canal No vital, con planificación virtual y guía endodóntica. Se utilizó el programa de acceso gratuito, Bluesky Plan®, para la planifica-ción digital de la guía endodóntica. El tratamiento se realizó en dos citas. Conclusión: el uso de tecnología para la resolución de casos de alta complejidad en endodoncia, podría ayudar a mejorar el pronóstico de estos dientes y ser una alternativa más segura para reducir la posibilidad de perforación y preservar estructura dental.

ABSTRACT: The aim: of this case report is to present the endodontic treatment of an anterior tooth with an obliterated pulp canal, with the help of guided endodontics. Male patient with no relevant medical history, currently with orthodontic treatment. Tooth 2.1 had a history of dental trauma and presented tenderness to percussion. The CBCT exam showed a completely obliterated root canal in the cervical and middle third, and apical radiolucency. Diagnosis: Symptomatic Apical Periodontitis. Treatment: Root canal treatment with virtual planning and endodontic guide. Bluesky Plan® free access program was used for the digital planning of the endodontic guide. The treatment: was made in two sessions. Conclusion: the use of technology for the resolution of high complexity cases in endodontics could help improve the prognosis of these teeth and be a safer alternative to reduce the possibility of perforation and preserve more tooth structure.

Efficiency and Temperature Rise of File Ablation by Neodymium:Yttrium-Aluminum-Perovskite Laser In Vitro.

INTRODUCTION: Retrieving a separated file in the root canal system requires a skilled clinician. A metal file can be removed by ablation via the neodymium:yttrium-aluminum-perovskite (Nd:YAP) laser; however, the efficiency and potential hazards of the ablation procedure are still unclear. The aim of this study was 2-fold: to investigate the efficiency of file ablation using the Nd:YAP laser and to evaluate the rise in temperature of the root surface in vitro. METHODS: In part 1 of this study, #10 and #15 C-files (VDW GmbH, Munich, Germany) and ProTaper Next X1 and X2 files (Dentsply Maillefer, Ballaigues, Switzerland) were selected. Under 8.5×, the Nd:YAP laser was used to ablate the files starting at the tip of the file. The length of the file was recorded after each 5-pulse ablation. In part 2 of this study, 3 files each of the #15 C-file and the ProTaper Next X2 were separated in 6 distal roots of mandibular second molars with single canals. Two-pulse and 5-pulse modes were used to ablate the separated files, and the rise in root surface temperature was recorded with an infrared camera. Another 3 unaltered distal roots served as the negative control. For scanning electron microscopic evaluation, the teeth were split with bone scissors and observed under a scanning electron microscope to evaluate the surface change of the file and the root canal wall. RESULTS: The average length of the ablated files after each 5-pulse interval was 0.113-0.158 mm with no statistical difference between the different files.The temperature rise of the negative control group (mean ± standard deviation = 1.86° ± 0.11°C and 5.81° ± 0.35°C for the 2- and 5-pulse group) was significantly lower than the roots with separated files (mean ± standard deviation = 3.74° ± 0.20°C and 4.02° ± 0.11°C for 2-pulse C-file and ProTaper Next X2; 8.47° ± 0.19°C and 9.04° ± 0.20°C for 5-pulse C-file and ProTaper Next X2). The temperature rise of all groups was lower than 10°C. The 2-pulse group showed a lower temperature rise than the 5-pulse group. The diameter or the type of alloy had no effect on the temperature rise. CONCLUSIONS: Separated files (stainless steel or nickel-titanium alloy) can be ablated by the Nd:YAP laser. When the number of pulses is less than 5, the temperature rise of the root surface is considered safe to the surrounding periodontium.

Minimization of Tooth Substance Removal in Normally Calcified Teeth Using Guided Endodontics: An In Vitro Pilot Study.

INTRODUCTION: This study evaluated the success rate of and tooth substance removal required for computer-guided preparation of endodontic access cavities. METHODS: Thirty acrylic typodont teeth with root canals (10 each of tooth numbers 11, 14, and 17) were randomly allocated to a study or control group (15 teeth per group). In the study group, teeth were fixed in acrylic resin and subsequently digitized using a laboratory scanner. A cone-beam computed tomographic scan was then taken. Access cavity preparations were planned virtually, and a template was 3-dimensionally printed. In the control group, access cavities were prepared using the conventional access technique. Tooth substance removal was assessed by weighing teeth before and after preparation. Volume loss was analyzed statistically by use of the Wilcoxon-Mann-Whitney test at a significance level of P < .05. RESULTS: Using guided endodontics, 93.3% of root canals were located successfully compared with 100% of root canals using the conventional technique. In the control group, the mean tooth substance removal was 16.1 ± 3.7 mm³ for incisors, 44.2 ± 8.9 mm³ for premolars, and 99.3 ± 3.1 mm³ for molars. In the study group, significantly less tooth substance was removed; substance loss was 10.3 ± 1.1 mm³ for incisors, 29.3 ± 4.2 mm³ for premolars, and 51.8 ± 5.3 mm³ for molars. CONCLUSIONS: The use of guided endodontics in normally calcified teeth enables the preservation of a significant amount of tooth substance. However, this advantage must be carefully balanced against a greater radiation burden and risk of perforation, higher costs, and more difficult debridement and visualization of the pulp chamber and root canals.

Chamberless Endodontic Access for Treatment of Calcified Anterior Central Incisors.

INTRODUCTION: Modern techniques for treating maxillary anterior central incisors with calcified canals emphasize maintaining coronal dentin with small crown access. Alternatively, traditional retrograde surgical procedures are focused on creating an apical seal predominately limited to the remaining resected apical one third of the root canal space. A treatment option for calcified anterior teeth, with avoidance of traditional orthograde access, is presented. Chamberless endodontic access (CEA) to the canal is chosen in this case, leveraging a previous surgical treatment and osseous defect to create straight line canal access. METHODS: A tooth presenting with a chronic apical abscess and an apparent previous apical surgery was instrumented and obturated using a CEA avoiding the traditional orthograde approach to the root canal system. Straight line approach was achieved retrograde and canal instrumentation was performed using ultrasonic activated U-files. Canal obturation was accomplished with warm vertical condensation technique followed by placement of an apical retroseal. RESULTS: A successful 52-month outcome demonstrated the viability of CEA facilitating retrograde instrumentation and obturation. CONCLUSIONS: Use of CEA simultaneously protected the clinical crown and provided a successful clinical outcome. A viable option for treatment of an anterior calcified canal and abscess due to dental trauma, CEA mitigates many of the risks associated with the treatment of calcified root anatomy.

Comparação do alargamento apical do canal radicular através dos sistemas de instrumentação SAF e Reciproc / Comparison of apical enlargement of the root canal through SAF and Reciproc instrumentation systems

Objetivo: Comparar o aumento percentual da área da secção reta transversal de canais radiculares, no nível de 3 mm aquém do ápice radicular, após instrumentação com dois sistemas de instrumento único. Métodos: Dezenove primeiros molares inferiores extraídos tiveram as raízes mesiais seccionadas no nível de 3 mm aquém do ápice radicular, sendo os 2 milímetros finais de cada raiz removidos e descartados, para proceder a mensuração da área pré-operatória, através de estereomicroscopia. As raízes foram instrumentadas com os sistemas SAF e Reciproc R25.08 e procedeu-se nova mensuração para comparação do aumento percentual da área. O aumento percentual da área da secção reta transversal foi comparado e analisado estatisticamente pelo teste t de Student. O nível de significância foi estabelecido em 5% (p < 0,05). Resultados: O aumento percentual da área dos canais foi significativamente maior para o grupo Reciproc (p = 0,001) em comparação com o grupo SAF. Os canais instrumentados com o sistema SAF tiveram sua área aumentada em média 53,5%, enquanto que nos instrumentados com o sistema Reciproc a média foi 154,5%. Conclusão: O sistema Reciproc proporcionou um aumento percentual da área da secção reta transversal dos canais radiculares, no nível dos 3 mm apicais, 3 vezes maior que o sistema SAF.

Aim: To compare the percentage increase in the cross-sectional area of root canals, at the level of 3 mm from the root apex after instrumentation with two single instrument systems. Methods: The roots of 19 extracted mandibular first molars were sectioned 3 mm short of the apex level, with the final 2 millimeters of each root removed and discarded in order to enable the preoperative area to be measured by stereomicroscopy. Subsequently, the roots were instrumented with the SAF and Reciproc 25/.08 systems, alternating the technique used per canal from root to root, and a new measurement was performed. After, the percentage increase in area was calculated considering the values of the original and the final area. The Student'st-test was applied to the results, with a level of significance set at 5%. Results: The percentage increase in area of the root canals was significantly higher for the Reciproc (p = 0.001) when compared to the SAF group. In the canals instrumented with the SAF system, the mean increase in area was 53.5%, while in those using the Reciproc system, it was 154.5%. Conclusion:The Reciproc system produced a 3-fold higher percentage increase in the cross-sectional area of the root canals at the level of 3 mm from the root apex than did the SAF system.

Influência do acesso minimamente invasivo na fratura de dentes tratados endodonticamente - uma revisão de literatura / Influence of minimally invasive access on fracture of endodonti-cally treated teeth- a literature review

O acesso à cavidade pulpar é a etapa do tratamento endodôntico que tem como objetivo expor a embocadura dos canais radiculares. Por muito tempo, o formato ideal da cavidade era aquele que proporcionasse a criação de uma trajetória reta ao canal, com a remoção completa do teto da câmara pulpar. Porém, nas últimas décadas, foi investigado um desgaste excessivo de dentina que possibilita a redução da resistência do dente. Então, propuseram novo formato de cavidade de acesso, que permite a preservação máxima possível das estruturas de suporte, objetivando aumentar a resistência de dentes tratados endodonticamente. Apesar das vantagens, supostamente atribuídas aos acessos minimamente invasivos, esse formato tem sido questionado por dificultar a visibilidade da entrada dos canais, localização, e possibilidade de deixar áreas intocadas nas paredes dos canais. Diante disso, este trabalho realizou um levantamento bibliográfico a fim de verificar se há consistência científica quanto à interferência do acesso coronário na resistência dentária. Concluiu-se que o acesso minimamente invasivo não apresentou diferença quanto ao aumento da resistência à fratura de dentes tratados endodonticamente quando comparado ao acesso tradicional, entretanto, o tema ainda é relevante e os benefícios dessa técnica devem ser investigados clinicamente a longo prazo.

Access to the pulp cavity is the stage of endodontic treatment that aims to expose the mouth of the root canals. For a long time, creating a straight path to the canal, with the complete removal of the pulp chamber roof, was the ideal cavity format. However, in recent decades, excessive dentin wear, which makes it possible to reduce tooth strength, has been investi-gated. So, a new access cavity format, which allows the maximum possible preservation of the support structures, was proposed to increase the resistance of endodontically treated teeth. Despite the advantages supposedly attributed to minimally invasive accesses, this format has been questioned for hindering the visibility of the entrance to the channels, the location, and the possibility of leaving untouched areas on the walls of the channels. Therefore, this work carried out a bibliographical survey to verify the scientific consistency regarding the interference of coronary access in dental resistance. The minimally inva-sive access showed no difference regarding increased fracture resistance of endodontically treated teeth compared to the traditional access. However, the topic is still relevant, and its benefits, in the long term, should be clinically investigated.

Guided endodontic treatment of multiple teeth with dentin dysplasia: a case report.

BACKGROUND: To report the outcome of guided endodontic treatment (GET) of a case of dentin dysplasia with pulp canal calcification (PCC) and apical periodontitis based on the use of a 3D-printed template designed by merging cone-beam computed tomography (CBCT) and surface scan data. CASE PRESENTATION: A 12-year old female with radicular dentin dysplasia type I (DD-1) presented for endodontic treatment. Radiography revealed PCC in all teeth and apical radiolucency in seven teeth (12, 15, 26, 31, 32, 36 and 46). Tooth 36 had the most acute symptoms and was thus treated first by conventional access cavity preparation and root canal detection. Despite meticulous technique, the distal and mesiolingual canals were perforated. The perforations were immediately repaired with mineral trioxide aggregate, and the decision was made to switch to guided endodontic treatment for the remaining 6 teeth. CBCT and intraoral surface scans were acquired and matched using coDiagnostix planning software (Dental Wings Inc.), the respective drill positions for root canal location were determined, and templates were virtually designed and 3D-printed. The template was positioned on the respective tooth, and a customized drill was used to penetrate the calcified part of the root canal and perform minimally invasive access cavity preparation up to the apical region. All root canals were rapidly and successfully located with the templates. At 1-year follow-up, clear signs of apical healing were present in all treated teeth. CONCLUSIONS: In patients with dentin dysplasia, conventional endodontic therapy is challenging. GET considerably facilitates the root canal treatment of teeth affected by dentin dysplasia.

Guided modern endodontic microsurgery by use of a trephine bur / Gyökércsúcs rezekciója navigált endodontiai mikrosebészeti technikával

Surgical guides and three-dimensional (3D) planning softwares used in everyday dental implantology open new possibilities in other fields of dentistry. While using the operation microscope in endodontic microsurgery provides more precise apicectomy, there is still no consent on the exact localisation and size of the bony window to be prepared for this surgery. Our aim is to describe a new, guided endodontic microsurgery method when osteotomy and apicectomy are planned in a 3D software and performed with a trephine bur. Based on data from Cone Beam Computed Tomography, planning of the surgical guide was performed with a 3D planning software (Smart Guide, dicomLAB, Hungary) in order to define the size of the bony window, the angulation and the depth of the trephine bur during the apicectomy. After preparing a mucoperiosteal flap, with the help of the dentally supported surgical guide, the trephine bur removes the cortical bone and the apex of the root simultaniously. Following the modern microsurgical protocol, after performing the ultrasonic retrograde preparation, mineral trioxide aggregate (ProRoot MTA; Dentsply Maillefer, Ballaigues, Switzerland) is placed as a retrograde filling to close the resected area. After the uneventful healing period, a complete bony regeneration can be seen on the 1-year follow up X-ray. The patient is symptom-free. This technique is considered to be faster and more precise than the non-guided endodontic microsurgery carried out without the utilization of a trephine bur. Orv Hetil. 2020; 161(30): 1260-1265.

Intentional reimplantation of left lower second molar as an alternative to extraction: a case report / Reimplante intencional del segundo molar inferior como alternativa a la extracción: reporte de caso

In patients who need endodontic re-treatment, and where the prognosis for surgical or non-surgical re-treatment is poor or treatment may be risky, one alternative is to opt for extraction of the affected tooth and replacement by an implant. However treatment by intentional reimplantation (IR) is also a possibility. The object of the present study was to present a case of a patient aged 71 years who needed endodontic re-treatment, where IR treatment was selected. The patient reported spontaneous pain which disappeared completely with the use of analgesics. This tooth had previously been treated endodontically around 1 year earlier, and no pain was reported in the first two months after treatment.Nonetheless, about 3 months before the present consultation, intensity of the symptoms had increased with a sensation of pressure in the apical-coronal direction. Cone-beam computerised tomography (CBCT) showed a periapical lesion in tooth 3.7. Based on the clinical and imaging examinations, acute apical periodontitis was diagnosed in tooth 3.7.The tooth was treated by IR. It was carefully extracted and inspected for cracks or perforations. It was treated under the microscope with root resection, and then retrograde obturation was carried out with bioceramic material. The tooth was then repositioned in its alveolus. It was immobilised for 15 days, after which the patient could return gradually to normal masticatory function. In the 6 months check-up the patient presented no pain or sensitivity to percussion. No root resorption or periapical radiolucency was observed in the periapical X-ray. We conclude that IR is an alternative to extraction followed or not by prosthetic treatment, for patients who need endodontic re-treatment. The treatment presents good levels of success, and of acceptance by the patient.

En pacientes que necesitan de retratamiento endodóntico y el retratamiento quirúrgico o no quirúrgico tiene un pronóstico desfavorable o puede ser riesgoso, se puede optar por la extracción del diente afectado y su reemplazo por implante o se puede elegir el tratamiento mediante la técnica de reimplante intencional (RI). El objetivo del presente estudio fue presentar un caso de paciente de 71 años con necesidad de retratamiento endodóntico, donde se optó por la realización del RI. Paciente relatava dolor espontáneo que desaparecia completamente con el uso de analgésicos. Este diente ya había sido tratado endodónticamente hace alrededor de 1 año, y el paciente noreportó dolor en los primeros dos meses después del tratamiento.No obstante, hace aproximadamente 3 meses la intensidad de los síntomas aumentó, junto con la sensación de presión en el sentido ápice-corona. La tomografía computarizada cone-beam (TCCB) mostró lesión periapical en el diente 3.7. Basado en el examen clínico e imagenológico se diagnosticó periodontitis apical aguda en el diente 3.7.Para el tratamiento se realizó la técnica de RI, siendo extraído el diente cuidadosamente, e inspeccionado a fin de localizar fisuras o perforaciones. El diente fue tratado bajo microscopio y se realizó la resección de la raíz. Se realizó la obturación retrógrada con material biocerámico. Enseguida el diente fue reposicionado en su alveolo, la inmovilización fue realizada durante 15 días y la paciente logró retornar gradualmente a su función masticatoria. En el seguimiento de 6 meses la paciente no presentó dolor o sensibilidad a la percusión. En la radiografía periapical no se observó resorción radicular o radiolucencia periapical. Concluimos que el RI en pacientes que necesitan retratamiento endodóntico es una alternativa a la realización de la exodoncia seguida o no, de tratamiento protético, donde existe una buena aceptación por parte del paciente y éxito en el tratamiento.