Artificial Intelligence Techniques for Automatic Detection of Peri-implant Marginal Bone Remodeling in Intraoral Radiographs.

Peri-implantitis can cause marginal bone remodeling around implants. The aim is to develop an automatic image processing approach based on two artificial intelligence (AI) techniques in intraoral (periapical and bitewing) radiographs to assist dentists in determining bone loss. The first is a deep learning (DL) object-detector (YOLOv3) to roughly identify (no exact localization is required) two objects: prosthesis (crown) and implant (screw). The second is an image understanding-based (IU) process to fine-tune lines on screw edges and to identify significant points (intensity bone changes, intersections between screw and crown). Distances between these points are used to compute bone loss. A total of 2920 radiographs were used for training (50%) and testing (50%) the DL process. The mAP@0.5 metric is used for performance evaluation of DL considering periapical/bitewing and screws/crowns in upper and lower jaws, with scores ranging from 0.537 to 0.898 (sufficient because DL only needs an approximation). The IU performance is assessed with 50% of the testing radiographs through the t test statistical method, obtaining p values of 0.0106 (line fitting) and 0.0213 (significant point detection). The IU performance is satisfactory, as these values are in accordance with the statistical average/standard deviation in pixels for line fitting (2.75/1.01) and for significant point detection (2.63/1.28) according to the expert criteria of dentists, who establish the ground-truth lines and significant points. In conclusion, AI methods have good prospects for automatic bone loss detection in intraoral radiographs to assist dental specialists in diagnosing peri-implantitis.

Mechanical properties and ultrastructural characteristics of a glass fiber-reinforced composite.

PURPOSE: To examine the ultrastructural characteristics of a fiber-reinforced composite (FRC) and its behavior in vitro as a framework for fixed partial dentures (FPDs). METHODS: A total of 40 specimens were prepared using extracted teeth fixed in methacrylate blocks as supports for the FPD, then the specimens were divided into four groups depending on whether a retaining box was used to fix the FPD to the support teeth, and on whether a composite pontic was assembled on top of the fibers. Fracture testing was performed in a universal testing machine (1 mm/minute). Fracture strength values and failure types were statistically compared for each group. RESULTS: Using retaining boxes did not improve the mechanical behavior of the restorative system. The weakest element of the system was the composite tooth constructed on top of the FRC.

Interest areas for training in endourology, laparoscopy and robotics: results of a multicentric survey among Spanish residents.

OBJECTIVES: To determine the current status of the training of Urology Resident's in Laparoscopic surgery, robotics and endourology. METHODS: We performed a survey among Spanish Urology Residents between 2011 and may 2012. We designed a survey that was disseminated through the web page of the Spanish Society of Laparoscopic and Robotic surgery (SECLA) (www.seclaendosurgery.com) to all residents from every Spanish hospital. The survey was divided in four blocks: General data, data of the Training Hospital, data of the surgical procedures (endoscopic, laparoscopic and robotic) and training features. We performed a descriptive study of the results. RESULTS: 36 Urology residents out of a total of 384 answered the survey (9,3%). In reference to endoscopic procedures 25% of the residents had never been involved on a percutaneous nephrostomy (n=36), and did not expect to do it. On the contrary, 77% have performed ureterorrenoscopy as first surgeon (n=36) and 25% have participated in more than 10 procedures. 54.4% of the participants took part as surgeons in percutaneous nephrolithotomies (n=28) and 79% looked forward to do them. Participation of residents in Da Vinci Robot assisted laparoscopic procedures is low. Laparoscopic procedures are very attractive and their participation is reduced as procedure complexity increases. CONCLUSIONS: 41.6% of participants think their training is adequate whereas 58,3% think it is not. 88% think their training could improve through courses and seminars and acquiring a greater degree of responsibility.

Assessment of pH Value and Release of Calcium Ions in Calcium Silicate Cements: An In Vitro Comparative Study.

The goal of this study was to evaluate the pH and the release of calcium from four calcium-silicate-based cements. METHODS: Four materials were tested (ProClinic MTA; Angelus MTA; ProRoot MTA; Biodentine). The palatal canal root of acrylic upper molars was filled with each cement. Afterwards, they were set in phosphate-buffered saline. Measurements were taken by atomic adsorption spectroscopy (AAS) at 3, 24, 72, 168, 336, 672, and 1008 h. The pH was measured at the same timepoints. Kruskal-Wallis tests were carried out in each period, as the Kolmogorov-Smirnov and Shapiro-Wilk tests showed no parametric results. RESULTS: Significant differences (p < 0.05) in calcium release were found at the 3-, 24-, and 72-hour evaluations. All of the analyzed groups presented a release of calcium ions up to 168 h, and the general tendency was to increase up to 672 h, with a maximum release of 25.45 mg/g in the ProRoot group. We could only observe significant differences (p < 0.05) in pH value over 168 h between the Biodentine (7.93) and Angelus MTA (7.31) groups. CONCLUSIONS: There were significant differences (p < 0.05) in calcium release. Nevertheless, no significant differences (p > 0.05) in the pH values were found at the studied timepoints, except for the values at 168 h.

Morphological Study of Dental Structure in Dentinogenesis Imperfecta Type I with Scanning Electron Microscopy.

Background: Dentinogenesis imperfecta type I (DGI-I) is a hereditary alteration of dentin associated with osteogenesis imperfecta (OI). Aim: To describe and study the morphological characteristics of DGI-I with scanning electron microscopy (SEM). Material and methods: Twenty-five teeth from 17 individuals diagnosed with OI and 30 control samples were studied with SEM at the level of the enamel, dentin-enamel junction (DEJ) and four levels of the dentin, studying its relationship with clinical-radiographic alterations. The variables were analysed using Fisher's exact test, with a confidence level of 95% and asymptotic significance. Results: OI teeth showed alterations in the prismatic structure in 56%, interruption of the union in the enamel and dentin in 64% and alterations in the tubular structure in all of the cases. There is a relationship between the severity of OI and the morphological alteration of the dentin in the superficial (p = 0.019) and pulpar dentin (p 0.004) regions. Conclusions: Morphological alterations of the tooth structure are found in OI samples in the enamel, DEJ and dentin in all teeth regardless of the presence of clinical-radiographic alterations. Dentin structural anomalies and clinical dental alterations were observed more frequently in samples from subjects with a more severe phenotype of OI.

Bladder carcinoma data with clinical risk factors and molecular markers: a cluster analysis.

Bladder cancer occurs in the epithelial lining of the urinary bladder and is amongst the most common types of cancer in humans, killing thousands of people a year. This paper is based on the hypothesis that the use of clinical and histopathological data together with information about the concentration of various molecular markers in patients is useful for the prediction of outcomes and the design of treatments of nonmuscle invasive bladder carcinoma (NMIBC). A population of 45 patients with a new diagnosis of NMIBC was selected. Patients with benign prostatic hyperplasia (BPH), muscle invasive bladder carcinoma (MIBC), carcinoma in situ (CIS), and NMIBC recurrent tumors were not included due to their different clinical behavior. Clinical history was obtained by means of anamnesis and physical examination, and preoperative imaging and urine cytology were carried out for all patients. Then, patients underwent conventional transurethral resection (TURBT) and some proteomic analyses quantified the biomarkers (p53, neu, and EGFR). A postoperative follow-up was performed to detect relapse and progression. Clusterings were performed to find groups with clinical, molecular markers, histopathological prognostic factors, and statistics about recurrence, progression, and overall survival of patients with NMIBC. Four groups were found according to tumor sizes, risk of relapse or progression, and biological behavior. Outlier patients were also detected and categorized according to their clinical characters and biological behavior.

Robotic Anderson-Hynes dismembered pyeloplasty: initial experience.

INTRODUCTION: The introduction of the da Vinci(®) robotic system in 2000 has been a new step forward in the treatment of ureteropelvic junction obstruction (UPJO). The aim of this study was to analyse our initial experience with robot-assisted dismembered Anderson-Hynes pyeloplasty and to perform a bibliographic review on the topic. PATIENTS AND METHODS: We performed 11 robot-assisted pyeloplasties between March 2007 and April 2011. UPJO diagnosis was made on clinical presentation and imaging techniques (CT scan and intravenous urography). All patients underwent basal and diuretic isotopic renograms to evaluate the degree of obstruction and impaired renal function. Median follow-up was 10 (range 1-26) months. RESULTS: Mean patient age was 38.8 (range 23-62) years. There were six women (55%) and five men (45%). All cases were primary surgeries. In four patients the cause of UPJO was a crossing vessel; the other seven patients had intrinsic obstruction. One case was associated with extraction of a calyceal lithiasis. Mean operative time was 189.4 min (125-270 min). Average time from robotic arms docking was 116.5 (range 55-180) min. Average hospital stay was 4.18 (range 2-8) days. Conversion to open or laparoscopic surgery was not necessary in any case and there were no postoperative complications. Postoperative radiological evaluation and renograms showed good results in all cases. CONCLUSIONS: Robotic surgery offers better ergonomics, enhanced three-dimensional (3D) vision and more precise movements, easing intracorporeal suturing.These advantages make robotic pyeloplasty a reproducible technique that combines the high success rates of open surgery and the benefits of laparoscopic surgery.

Áreas de interés en el aprendizaje de endourología, cirugía laparoscópica y robótica: resultados de una encuesta multicéntrica en residentes españoles / Interest areas for training in endourology, laparoscopy and robotics: results of a multicentric survey among spanish residents

OBJETIVO: Determinar el estado actual de la formación de los residentes de Urología, en España en cirugía laparoscópica, robótica y endourológica. MÉTODOS: Se realizó una encuesta (Figura 1) dirigida a los residentes españoles, durante el periodo comprendido entre los años 2011 y mayo de 2012. Diseñamos una encuesta que fue difundida a través de la página web (www.seclaendosurgery.com) de la Sociedad Española de Cirugía Laparoscópica y Robótica (SECLA) a todos los residentes en formación en cualquier centro hospitalario español. La encuesta se dividió en cuatro bloques: datos generales, datos generales del centro donde se realiza la residencia, datos de técnicas quirúrgicas (endoscópicas, laparoscópicas y robóticas) y aspectos formativos. Se realizó un estudio descriptivo de los resultados. RESULTADOS: Sobre un total de 384 residentes en Urología, 36 contestaron a la encuesta (9,3%). Los datos obtenidos referidos a procedimientos endoscópicos demostrarón que un 25 % de los encuestados nunca ha participado en la colocación de una nefrostomía percutánea (n=36), ni espera hacerlo. Por el contrario, un 77 % afirma haber realizado como cirujano una ureterorrenoscopia (n=36). y el 25% lo hizo en más de diez procedimientos. El 54’4 % de los encuestados ha participado como cirujano en nefrolitectomías percutáneas (n=28) y el 79% espera hacerlo. La participación de los residentes en los procedimientos asistidos por robot da Vinci es baja. Los procedimientos laparoscópicos son de gran interés y su participación se reduce según se incrementa el grado de complejidad del procedimiento. CONCLUSIÓN: El 41,6% de los encuestados piensa que su formación es adecuada mientras que el 58,3% piensa que no lo es. El 88% piensan que su formación se podría mejorar con cursos y seminarios y adquiriendo mayor grado de responsabilidad en quirófano y el 50% que su formación se podría complementar con rotaciones externas y/o fellowships

OBJECTIVES: To determine the current status of the training of Urology Resident`s in Laparoscopic surgery, robotics and endourology. METHODS: We performed a survey among Spanish Urology Residents between 2011 and may 2012. We designed a survey that was disseminated through the web page of the Spanish Society of Laparoscopic and Robotic surgery (SECLA) (www.seclaendosurgery.com) to all residents from every Spanish hospital. The survey was divided in four blocks: General data, data of the Training Hospital, data of the surgical procedures (endoscopic, laparoscopic and robotic) and training features. We performed a descriptive study of the results. RESULTS: 36 Urology residents out of a total of 384 answered the survey (9,3%). In reference to endoscopic procedures 25% of the residents had never been involved on a percutaneous nephrostomy (n=36), and did not expect to do it. On the contrary, 77% have performed ureterorrenoscopy as first surgeon (n=36) and 25% have participated in more than 10 procedures. 54.4% of the participants took part as surgeons in percutaneous nephrolithotomies (n=28) and 79% looked forward to do them. Participation of residents in Da Vinci Robot assisted laparoscopic procedures is low. Laparoscopic procedures are very attractive and their participation is reduced as procedure complexity increases. CONCLUSIONS: 41.6% of participants think their training is adequate whereas 58,3% think it is not. 88% think their training could improve through courses and seminars and acquiring a greater degree of responsibility

Estudio de la microfiltración de amalgamas adheridas con sistemas adhesivos fotopolimerizables / Study of microleakage of bonded amalgams with light cured adhesive systems

Fundamento: al combinar un sistema adhesivo con la amalgama de plata se pretende mejorar el sellado de la Interfase. En este trabajo se valora la capacidad de sellado de los adhesivos fotopolimerizables en este tipo de restauraciones. Material y método: mediante un estudio de penetración de colorante y un sistema informático digital, se determinó cuantitativamente la microfiltración de restauraciones de amalgama realizadas con adhesivos fotopolimerizables, barniz de copal y un sistema autopolimerizable. Resultados: el empleo de sistemas adhesivos en restauraciones de amalgama genera una interfase entre la amalgama y el adhesivo y otra entre el adhesivo y la dentina. La microfiltración en la primera interfase es mayor en los adhesivos fotopolimerizables respecto al autopolimerizab e y el barniz de copal. Sin embargo, la microfiltración en la segunda interfase es menor en los dos sistemas adhesivos respecto al barniz de copal (p<0.05) Conclusión: los adhesivos fotopolimerizables producen un sellado insuficiente en restauraciones de amalgama (AU)