Three-dimensional evaluation of skeletal and dental changes in patients with skeletal class III malocclusion and facial asymmetry after surgical-orthodontic treatment.

OBJECTIVE: To evaluate skeletal and dental changes in patients with skeletal Class III malocclusion and facial asymmetry after surgical-orthodontic treatment using cone-beam computerized tomography (CBCT). METHODS: This study included forty adult patients diagnosed with skeletal Class III malocclusion and asymmetry who underwent either isolated mandibular surgery or bimaxillary surgery. CBCT scans were taken before treatment (T0), at the completion of presurgical orthodontic treatment (T1) and after treatment (T2). Mimics 17.0 and 3-Matics 7.0 were used to measure skeletal and dental parameters. Skeletal and dental changes within each group from pretreatment to posttreatment were assessed, and Pearson correlation analysis was used to analyze the correlations among skeletal changes. RESULTS: The three-dimensional changes in condylar position were insignificant after surgical-orthodontic treatment in either group (P > 0.05). However, in the one-jaw surgery group, there were significant backward rotations of the condyle and ramus on the nondeviated side (P < 0.05), and the condyle on the deviated side rotated inward and forward significantly in the two-jaw surgery group (P < 0.05) at T2. There were no significant differences in the changes in the total alveolar bone thickness of bilateral first molars during dental decompensation (P > 0.05). The ratio between the buccal and the total bone thickness around the maxillary first molar on the deviated side decreased significantly at T1, as did those around the mandibular first molar on the nondeviated side (P < 0.05). CONCLUSIONS: Condylar angulations were less stable after treatment (7 to 9 months after surgery) in both the one-jaw and the two-jaw surgery groups, while condylar displacements were insignificant. In addition, orthodontists should keep a watchful eye to the relative position of the root in the alveolar bone during tooth decompensation.

Routine and complicated extractions: avoiding and managing complications.

Dental extractions are commonly performed procedures in dentistry. For a number of different reasons, there can be serious complications both during surgical procedures and during patient recovery. Many of these complications can be avoided by recognizing "red flags" in advance of untoward events and by taking steps to prevent or manage such problems. Prior to surgery, the dentist needs quality radiographs, must be familiar with the patient's health conditions and medications, and have the knowledge and expertise to perform routine and "surgical" extractions safely, expeditiously, and with minimal (if any) loss of adjacent bone. This article, although not "all-inclusive," outlines procedures that help us either confirm correct methods we are already using or enhance our ability to become better. It reviews items that clinicians must be aware of and anticipate to allow exodontia to be done more smoothly and effectively.

Cross-Platform Ubiquitous Volume Rendering Using Programmable Shaders in VTK for Scientific and Medical Visualization.

The visualization toolkit (VTK) is a popular cross-platform, open source toolkit for scientific and medical data visualization, processing, and analysis. It supports a wide variety of data formats, algorithms, and rendering techniques for both polygonal and volumetric data. In particular, VTK's volume rendering module has long provided a comprehensive set of features such as plane clipping, color and opacity transfer functions, lighting, and other controls needed for visualization. However, due to VTK's legacy OpenGL backend and its reliance on a deprecated API, the system did not take advantage of the latest improvements in graphics hardware or the flexibility of a programmable pipeline. Additionally, this dependence on an antiquated pipeline posed restrictions when running on emerging computing platforms, thereby limiting its overall applicability. In response to these shortcomings, the VTK community developed a new and improved volume rendering module, which not only provides a modern graphics processing unit-based implementation, but also augments its capabilities with new features such as fast volume clipping, gradient-magnitude-based opacity modulation, render to texture, and hardware-based volume picking.

[Comprehensive endodontic treatment with the use of depo- and galvanophoresis with copper hydroxide-calcium].

In the blind and randomized study in cases of routine endodontic treatment of 460 teeth in 372 patients high efficacy of additional use of depo- and galvanophoresis with copper hydroxide-calcium according to the technique modified by the authors.

Commentary: A Translational Medicine Approach to Tooth Transplantation.

The autogenous tooth transplantation approach to replace missing teeth has been in use for a long time. Different surgical techniques have been developed to improve prognosis and longevity of transplanted teeth with complete root formation. Many factors reportedly affected short- and long-term success of the procedure: complications such as ankylosis and root resorption up to the tooth exfoliation have occurred frequently. Several studies have appeared on this issue over the years. However, outcomes of transplantations have not yet been conclusively determined as no randomized clinical trials have been published on this issue, and their effectiveness has been evaluated only in observational studies. On the other hand, interesting information from specific experimental studies on the healing pattern of the interface between the root surface and alveolar bone in the replantation/transplantation model, and from non-related studies dealing with mechanically induced periodontal trauma, has been available and potentially useful since the 1970s to 1980s. However, this information has not been incorporated into clinical literature regarding tooth autotransplantation. This commentary aims to show how information from related and unrelated experimental models was translated to a clinical setting and led to a novel approach, successfully applied, in the autotransplantation of a multirooted tooth with completed root formation.

Guided Autotransplantation of Teeth: A Novel Method Using Virtually Planned 3-dimensional Templates.

INTRODUCTION: The aim of this study was to introduce an innovative method for autotransplantation of teeth using 3-dimensional (3D) surgical templates for guided osteotomy preparation and donor tooth placement. METHODS: This report describes autotransplantation of immature premolars as treatment of an 11-year-old boy having suffered severe trauma with avulsion of permanent maxillary incisors. This approach uses modified methods from guided implant surgery by superimposition of Digital Imaging and Communications in Medicine files and 3D data sets of the jaws in order to predesign 3D printed templates with the aid of a fully digital workflow. RESULTS: The intervention in this complex case could successfully be accomplished by performing preplanned virtual transplantations with guided osteotomies to prevent bone loss and ensure accurate donor teeth placement in new recipient sites. Functional and esthetic restoration could be achieved by modifying methods used in guided implant surgery and prosthodontic rehabilitation. The 1-year follow-up showed vital natural teeth with physiological clinical and radiologic parameters. CONCLUSIONS: This innovative approach uses the latest diagnostic methods and techniques of guided implant surgery, enabling the planning and production of 3D printed surgical templates. These accurate virtually predesigned surgical templates could facilitate autotransplantation in the future by full implementation of recommended guidelines, ensuring an atraumatic surgical protocol.

In-depth morphological evaluation of tooth anatomic lengths with root canal configurations using cone beam computed tomography in North American population

Abstract Objective This study aimed to assess the association between tooth size and root canal morphology by using CBCT analysis. Methodology In this retrospective study, tooth anatomic lengths (crown and root lengths, buccolingual and mesiodistal dimensions) of 384 patients were assessed and correlated with Vertucci's root canal morphology classification. Data was analyzed for gender-related differences using the independent sample t-test, ANOVA, and the Pearson's correlation for a possible relation between anatomic lengths and canal morphology. Results The maxillary first and second premolars showed a greater predilection for Type IV and II variants, respectively, while the mandibular first premolar showed a greater predilection for Type II canal system. The root canal system of the mandibular second premolar showed maximal diversity (47% Type I, 30% Type II, and 20% Type III). The dimensions were greater in men regardless of tooth type. The most significant relation (p<0.05) between the anatomic size and canal morphology was observed in the maxillary first premolars, followed by the mandibular canines (buccolingual dimension) and the lower second premolars (crown length). Negative correlations existed between the crown length and the patient's age for the anterior teeth and mandibular second premolar (r=−0.2, p<0.01). Conclusions The most common canal formation for anterior teeth was the Type I. The anatomic lengths had the strongest influence on the canal configuration of the maxillary first premolar, with Type IV being the most common root canal system. The mandibular second premolars showed maximal diversity in the canal classification terms and had a significant correlation with their crown lengths. Clinical Relevance The complex relationship between the canal morphology and anatomic tooth sizes need meticulous awareness and recognition during endodontic procedures, in conjunction with the demographic variabilities.

Clinical, radiographic, and histologic perspectives on success and failure in endodontics.

There is a tremendous impact of multiple variables on the decision-making process in determining success or failure. The best approach to quality outcomes is to minimize the variables that can affect case adversity. Therefore, it behooves the clinician, who chooses to do endodontic therapy, to fully understand the level of treatment that is necessary to achieve success and to attain that level on a consistent basis. Additionally, the wise and prudent clinician should be able to assess completed treatment, with the proper integration of clinical and radiographic factors, in an environment that minimizes the shackles of bias and the dictates of cognitive dissonance.

Age estimation by pulp/tooth area ratio in anterior teeth using cone-beam computed tomography: comparison of four teeth

Abstract Objectives Age estimation is one of the most important factors in forensic medicine. Measuring secondary dentin deposition using cone-beam computed tomography images is an easy and noninvasive method. The aim of this study was to evaluate cone-beam computed tomography images as a reliable method to estimate chronological age by pulp/teeth ratio in anterior teeth in Iranian population. Methodology A total of 649 CBCT images from 377 Iranian patients aged between 20 and 69 years were evaluated. Pulp/teeth ratio (PTR) in maxillary and mandibular canine and central incisor teeth was measured in the axial and sagittal sections using OnDemand 3D Dental software. The Pearson correlation coefficient was determined to evaluate the correlation between the variables. Linear regression analysis, as well as age estimation formula, was used for each tooth separately. Results The regression analyses indicated that maxillary central incisors were more reliable for age estimation (R2=0.586 and standard error of estimate=7.045) compared with the other anterior teeth studied. Maxillary canine teeth had the lowest predictive power (R2=0.392 and standard error of estimate=8.387). Also, comparison of the axial and sagittal sections showed that the axial sections had a higher predictive power. (R2=0.48 for axial plans and R2=0.328 for sagittal plans) Conclusion The use of cone-beam computed tomography in age estimation by pulp/teeth ratio of anterior teeth is useful and a reliable method for age estimation in Iranian population.

Bone structure regeneration after low induction magnetic field treatment in teeth chosen for extraction.

PURPOSE: The aim of the work was to use and to evaluate the usefulness of the slow variable magnetic fields to aid the treatment of the teeth chosen for extraction. The marginal paradontium of periapical bone of teeth was in a state of extensive destruction. The teeth were chosen for extraction. MATERIAL AND METHODS: 13 patients were chosen. 10 of them had with endo-perio changes and 3 suffered from full tooth luxation and had the teeth replanted. Those people were to have an extraction procedure or were declared as impossible to treat in other dental offices. Patients underwent non-aggressive skaling, endodontic treatment and were exposed to slow variable magnetic fields generated by Viofor JPS, accordingly to methods and parameters suggested by Department of Propaedeutics in Dentistry of Pomeranian Medical University in Szczecin. The process of healing of changes was evaluated radiologically. RESULTS: RTG done after 2 weeks and after 2 months were evaluated in respect of bone regeneration. They show the bone structure concentration. A RTG evaluation after half a year, two and three years show a preservation of the bone structure concentration. CONCLUSIONS: The use of slow variable magnetic fields contributed to bone structure regeneration and to preserve teeth with recorded endo-perio syndrome. Endodontic treatment of replanted teeth, aided with magnetostimulation has stopped the osteolisis process.

[Analysis on curative effects of teeth with chronic apical periodontitis in elderly people].

OBJECTIVE: To study of the curative effect of teeth with chronic apical periodontitis in elderly people and the usage of assessment index. METHODS: Fifty eight teeth from 49 elderly and 50 teeth from 40 young patients were reexamined, which had received root canal therapy or resinifying therapy 2 to 9 years ago. The curative effects were evaluated based on clinical examination and radiographic assessment using periapical index (PAI). RESULTS: Statistically no significant difference for the overall healing rates between the two groups. But when the reexamination period was longer than 4 years, the healing rates in elderly people (58.0%) were significantly lower than those of the young people (87.1%). The treatment method and the size of the periapical lesion had significant influence on the results of the elderly people, whereas no influence on the young patients. According to our data, deep periodontal pocket and occlusal trauma were the main reasons of failure. CONCLUSION: The long-term curative effects of teeth with chronic apical periodotitis in elderly is lower than that of the young people. The PAI system is worth of utilizing popularly in the clinical dentistry.

Radiographic findings in the teeth and jaws of 14- to 17-year-old Estonian schoolchildren in Tartu and Tallinn.

Panoramic radiographs were taken of 392 Estonian schoolchildren (33% boys and 67% girls) aged 14-17 years, 197 in Tartu and 195 in Tallinn. The mean number of permanent teeth was 31.5. In 14% of the children one to four teeth (excluding wisdom teeth) were missing. The frequencies of missing wisdom teeth and supernumerary teeth agreed with those in the literature, being 17% and 3%, respectively. The mean number of radiographically detected carious teeth was 1.9 in Tartu and 3.3 in Tallinn. Secondary caries was common, being found radiographically in half of the schoolchildren. Endodontic treatment had been given to 13% of the subjects in Tartu and to 46% in Tallinn, the success rates being 47% and 44%, respectively. The percentage of radiographic signs in the mandibular condyles of girls (5%) was greater than that of the boys (1%). Changes in the maxillary sinuses were found in 16% of the children. Eight odontogenic cysts, one cyst of the incisal canal, and one solitary bone cyst were found. Tumors included two odontomas, two cemento-ossifying lesions, and one osteoma in the maxillary sinus. The health status of the jaws of the Estonian schoolchildren was considered to be fairly good.