Faculty Bibliography

Avulsion of permanent teeth is one of the most serious dental injuries, and a prompt and correct emergency management is very important for the prognosis. The International Association of Dental Traumatology (IADT) has developed a consensus statement after a review of the dental literature and group discussions. Experienced researchers and clinicians from various specialties were included in the task group. The guidelines represent the current best evidence and practice based on literature research and professionals' opinion. In cases where the data did not appear conclusive, recommendations were based on the consensus opinion or majority decision of the task group. Finally, the IADT board members were giving their opinion and approval. The primary goal of these guidelines is to delineate an approach for the immediate orurgent care of avulsed permanent teeth.

INTRODUCTION: The purpose of this study was to evaluate differences in torsional resistance using up-regulated speed of rotational spindle. METHODS: Three NiTi rotary instrument systems were selected in this study: K3XF (SybronEndo, Glendora, CA), BLX (B&L Biotech, Ansan, Korea), and OneShape (MicroMega, Besancon, France). The tip size and taper for all files were #25 and 0.06. Experimental groups (n = 10/group) were assigned to 2-, 60-, 350-, and 600-rpm groups by the rotational speed of spindle. Forty new files were used for each test. The file tip of 5-mm length was secured between brass plates. While keeping the file straight, it was rotated clockwise at a constant rotational speed until fracture occurred. The parameters of torsional resistance, torsional load (Ncm), and distortion angle ( degrees ) were measured using an AEndoS-k (DMJ System, Busan, Korea), and the toughness until fracture was computed from these data. The 1-way analysis of variance test was used to analyze the torsional resistance at a significance level of 95%. All fractured fragments were observed under a scanning electron microscope to evaluate the topographic features of the fractured surfaces. RESULTS: No significant difference in torsional resistance was found among groups when they were compared for ultimate strength at the maximum torque, fracture angle, and toughness. Scanning electron microscopic examination of the fractured cross-sectional surfaces revealed typical features of torsional fractures, concentric abrasion marks, and fibrous dimples from the torsional center. CONCLUSIONS: Under the conditions of the study, the torsional resistances of the rotary instruments were not affected by the rotational speed.

OBJECTIVES: To describe the use of open-source software for the post- processing of cone-beam computed tomography (CBCT) imaging for the assessment of periapical lesions development after endodontic treatment. METHODS: CBCT scans were retrieved from endodontic records of two patients. 3D virtual models, voxel counting, volumetric measurement (mm3), and mean intensity of the periapical lesion were performed with ITK Snap 3.0 software. 3D models of the lesions were aligned and overlapped through the MeshLab software, which performed an automatic recording of the anatomical structures, based on the best fit. Qualitative and quantitative analysis of the changes in lesions size after treatment were performed with 3DMeshMetric software. RESULTS: The ITK-SNAP 3.0 showed the smaller value corresponding to the voxel count and the volume of the lesion segmented in yellow, indicating reduction in volume of the lesion after the treatment. A higher value of the mean intensity of the segmented image in yellow was also observed, which suggested new bone formation. Color mapping and "point value" tool allowed the visualization of the reduction of periapical lesions in several regions. CONCLUSION: Researchers and clinicians in the monitoring of endodontic periapical lesions have the opportunity to use open-source software.

INTRODUCTION: Traumatic injury to the teeth can cause horizontal root fractures and inflammatory root resorptions (external and internal). Traditionally, traumatized teeth with horizontal root fractures resulting in pulp necrosis and inflammatory root resorptions are treated with conventional root canal therapy. METHODS: A 15-year-old boy had a history of traumatic injury to mature tooth #8 resulting in horizontal root fracture and pulp necrosis of the coronal fragment. A 7-year-old girl suffered an avulsion injury to immature tooth #9, which developed inflammatory replacement resorption and subsequently root fractured 15 months later. Another 16-year-old boy also suffered a history of traumatic injury to mature tooth #8, resulting in perforating root resorption. All teeth were treated with regenerative endodontic procedures using chemomechanical debridement, calcium hydroxide/triple antibiotic paste dressing, EDTA rinse, induction of periapical bleeding into the canal space, and a coronal mineral trioxide aggregate plug. In the tooth presenting with horizontal root fracture, only the coronal fragment was treated to preserve pulp vitality in the apical fragment for possible pulp tissue regeneration. RESULTS: After regenerative endodontic procedures, clinical signs/symptoms subsided, and inflammatory osteolytic lesions resolved in all traumatized teeth. Two teeth were followed for 19 months and 1 tooth for 5 years. At the last review of the teeth with horizontal root fractures, the first case showed healing by calcified tissue and the second case showed healing by fibrous connective and hard tissue. Tooth with perforating root resorption demonstrated a decrease in size of the resorptive defect. CONCLUSIONS: Based on these case reports, regenerative endodontic procedures have the potential to be used to treat traumatized teeth with horizontal root fracture and inflammatory root resorption.

Traumatic dental injuries (TDIs) of permanent teeth occur frequently in children and young adults. Crown fractures and luxations are the most commonly occurring of all dental injuries. Proper diagnosis, treatment planning and followup are important for improving a favorable outcome. Guidelines should assist dentists and patients in decision making and for providing the best care effectively and efficiently. The International Association of Dental Traumatology (IADT) has developed a consensus statement after a review of the dental literature and group discussions. Experienced researchers and clinicians from various specialties were included in the group. In cases where the data did not appear conclusive, recommendations were based on the consensus opinion of the IADT board members. The guidelines represent the best current evidence based on literature search and professional opinion. The primary goal of these guidelines is to delineate an approach for the immediate or urgent care of TDIs. In this first article, the IADT Guidelines for management of fractures and luxations of permanent teeth will be presented.

Avulsion of permanent teeth is one of the most serious dental injuries, and a prompt and correct emergency management is very important for the prognosis. The International Association of Dental Traumatology (IADT) has developed a consensus statement after a review of the dental literature and group discussions. Experienced researchers and clinicians from various specialties were included in the task group. The guidelines represent the current best evidence and practice based on literature research and professionals' opinion. In cases where the data did not appear conclusive, recommendations were based on the consensus opinion or majority decision of the task group. Finally, the IADT board members were giving their opinion and approval. The primary goal of these guidelines is to delineate an approach for the immediate orurgent care of avulsed permanent teeth.

INTRODUCTION: This multicenter, prospective, nonsignificant risk clinical study evaluated healing rates for molars 12 months after endodontic therapy using the GentleWave System (Sonendo, Inc, Laguna Hills, CA). METHODS: Eighty-nine patients needing endodontic therapy who met the inclusion criteria consented for this clinical study. All enrolled patients were treated with a standardized protocol consisting of conservative access, shaping of canals to #20/.07, GentleWave treatment, and warm vertical obturation. Six endodontists performed the clinical procedures and follow-up evaluations. Preoperative, intraoperative, and postoperative data were collected from the consented patients. Each patient was evaluated for clinical signs and symptoms. Two trained, blinded, and independent evaluators scored the subject's radiographs for signs of apical periodontitis using a periapical index. The teeth classified as healing or healed were considered as a success and accounted for the cumulative success rate of healing. Statistical analysis was performed by using the Fisher exact test, Pearson correlation, and multivariate logistic regression analyses of the preoperative prognostic factors at P = .05. RESULTS: Seventy-five teeth in 75 patients were evaluated at 12 months with a follow-up rate of 84.3%. The cumulative success of endodontic therapy was 97.3%. The success rates of necrotic and irreversible pulpitis were 92.9% and 98.4%, respectively; 3.8% of the patients experienced moderate postoperative pain within 2 days and no incidence of pain at 14 days, 6 months, and 12 months of initial therapy. Ten prognostic factors were identified using bivariate analyses. Using logistic analyses, the prognostic significant variable that was directly correlated to healing was the preoperative presence of lesions (P = .026). CONCLUSIONS: In this 12-month prospective multicenter clinical study, the GentleWave System showed a high level of success after a 12-month follow-up.

BACKGROUND: This prospective multi-center (PURE) clinical study evaluated healing rates for molars after root canal treatment employing the GentleWave(R) System (Sonendo, Inc., Laguna Hills, CA). MATERIAL AND METHODS: Eighty-nine patients met the inclusion criteria and consented for this clinical study after referral for a root canal treatment. All enrolled patients were treated with the GentleWave System. Five endodontists performed the clinical procedures and follow-up evaluations. Pre-operative, intra-operative, and post-operative data were collected from the consented patients. Each patient was evaluated for clinical signs and symptoms. Two trained, blinded, and independent evaluators scored the subject tooth radiographs for apical periodontitis using the periapical index (PAI). The teeth classified as healing or healed were considered as a success and composed of a cumulative success rate of healing. Statistical analysis was performed by using the Fisher's exact test, Pearson correlation, and multivariate logistic regression analyses of the pre-operative prognostic factors at 0.05 significance level. RESULTS: Seventy-seven patients were evaluated at six months with a follow-up rate of 86.5%. The cumulative success rate of healing was 97.4%. Eleven prognostic factors were identified using bivariate analyses. Using logistic analyses, the two prognostic significant variables that were directly correlated to healing were the pre-operative presence of periapical index (p value=0.016), and single treatment visits (p value=0.024). CONCLUSIONS: In this six-month PURE clinical study, the cumulative success rate of healing was 97.4% when patients were treated with the GentleWave(R) System. KEY WORDS: Healing rate, root canal treatment, molar, GentleWave, Sonendo(R), Multisonic Ultracleaning .

INTRODUCTION: Regenerative endodontic procedures (REPs) are usually used to treat human immature permanent teeth with necrotic pulps and/or apical periodontitis. Successful REPs result in the elimination of clinical signs/symptoms, the resolution of apical periodontitis, and, in some cases, thickening of the canal walls and/or continued root development with or without apical closure. REPs can restore the vitality of tissue in the canals of immature permanent teeth previously destroyed by infection or trauma. Vital tissue is inherited with immune defense mechanisms to protect itself from foreign invaders. Recently, REPs have also been used to successfully treat human mature permanent teeth with necrotic pulps and apical periodontitis. The purpose of this case series was to present the potential of using REPs for mature permanent teeth with necrotic pulps and apical periodontitis. METHODS: This case series consisted of 6 patients, 4 females and 2 males. The patients' ages ranged from 8-21 years old. Seven permanent teeth, 4 anterior and 3 molar teeth, with necrotic pulps and apical periodontitis were treated using REP. Radiographically, the root development of all teeth was almost completed except the apices of 2 molars, which showed slightly open. Complete chemomechanical debridement of the canals of the teeth was performed, and the canals were dressed with Metapaste (Meta Biomed Co, Ltd, Chungbuk, Korea) during treatment visits. Periapical bleeding into the canals was induced at the last treatment visit by placing a hand #20 or #25 K-file with the tip slightly bent through the apical foramina into the periapical tissues. A 3-mm thickness of mineral trioxide aggregate was placed into the coronal canals over semicoagulated blood. The access cavities were restored with either composite resin or amalgam. RESULTS: Follow-ups of the 7 teeth ranged from 8 to 26 months. The periapical lesions of 2 teeth were considered healed, and 5 teeth revealed healing. Clinical signs/symptoms were absent in all teeth at follow-up visits at different time points. None of the treated teeth responded to cold and electric pulp tests. CONCLUSIONS: This case series shows the potential of using REPs for mature teeth with necrotic pulp and apical periodontitis.

INTRODUCTION: A separated instrument in a root canal system has the potential of severely affecting the outcome of endodontic therapy. This study evaluated the effectiveness of the minimally invasive GentleWave System (Sonendo Inc, Laguna Hills, CA) in removing separated stainless steel endodontic files from the apical and midroot regions of molar root canals. METHODS: Thirty-six extracted human molars were accessed, and the glide path was confirmed to the apex. ISO #10, #15, and #20 K-file fragments of 2.5-mm length were separated at the apical (n = 18) or midroot (n = 18) region of the molars by engaging a weakened file with downward pressure. During analysis, the teeth were divided into 2 curved groups based on the curvature of the root (<30 degrees and >30 degrees ). The success rate of instrument removal and the treatment time were noted. Statistical comparison was done with the Fisher exact test and independent 2-sample t test (P < .05). RESULTS: The overall success rate of instrument removal when the separated files were engaged in the apical region was 61%, and for the midroot region, it was 83%. Less curved canals (<30 degrees ) showed a 91% success rate (n = 24), whereas canals with an angle of curvature greater than 30 degrees showed a 42% success rate (n = 12). The median treatment time for instrument retrieval was 10 minutes 44 seconds. CONCLUSIONS: The results revealed that the GentleWave System is effective in retrieving separated instruments while conserving the dentinal structure.