Mandibular ameloblastic fibroma in 6-years-old girl: a case report

Ameloblastic fibroma (AF) is defined in WHO classification as a ''neoplasm composed of proliferating odontogenic epithelium embedded in a cellular ectomesenchymal tissue that resembles dental papilla, and with varying degrees of inductive change and dental hard tissue formation''. AF is a rather uncommon tumor, accounting for only 2.5% of all odontogenic tumors. AF is a true mixed tumor, in which the epithelial and ectomesenchymal elements are neoplastic. AF raises at any age, ranging from 6 months to 42 years (mean 14.6 to 15.5 years); it does not show sex predilection. The lesion occurs in nearly 70% of cases in posterior areas of the mandible. Patients exhibit swelling of the jaw; pain is not usually described. Authors present a clinical and surgical management of an early onset of a large mandibular ameloblastic fibroma in a 6-year-old girsl.

Distorted perceptions of competence and incompetence are more than regression effects

Students inaccurately assess their own skills, especially high- or low-performers on exams. This study assessed whether regression effects account for this observation. After completing the Infection and Immunity course final exam (IIF), second year medical students (N = 143) estimated their performance on the IIF in terms of percent correct and percentile rank. Second year grade point averages (M2GPAs) were combined with the IIF results to form five subgroups: 1 = true-low (lowest third on both IIF and M2GPA, 2 = false-low (lowest third on IIF only), 3 = middle (neither lowest nor highest third on IIF), 4 = false-high (highest third on IIF only), 5 = true-high (highest third on IIF and M2GPA). The false-low and false-high groups were considered more susceptible to regression effects due to likely group misclassification. Differences between self-assessment and actual performance within each group and between the five groups were used to estimate what portion of observed differences is due to general tendencies versus regression effects. Results found that students accurately assessed their percent correct, but inaccurately assessed their percentile rank. No statistically significant differences existed between the true and false-low subgroups nor the true- and false-high subgroups. Percentages of mean differences suggest that while regression effects resulted in 50-75% over/under-estimates of scores by students who were misclassified, when they were merged with the true-low/high groups, they do not account for more than 14% of low performer over-estimates of their performance and high performer under-estimates of their performance. Accurate percent correct assessments and distorted percentile rank assessments are challenges in using instructional methods dependent on student self-assessments of their learning needs. Identifying and helping students with distorted perceptions of their test performances may be a key issue in such instructional approaches.

Mandibular distraction of the body and ramus

With the ever increasing interest in the field of osteodistraction techniques, the mandible is certainly the most studied anatomical site, both experimentally and clinically. Currently, the methods of mandibular distraction can be classified by position (intra- or extraoral), by the direction of distraction and by the site of application (toothborn, boneborn or hybrid fixation). To guarantee good results from the osteodistraction procedure, it is fundamental to have an accurate preoperative plan considering the correct classification and evaluation of the patient combined with a valid project regarding the direction of the distraction vector. One of the most important aspects to consider is the orientation of the distractor, especially if the defect to be corrected is three-dimensional. Regarding the correct planning of the operation, knowing the secondary effects of the distraction on the soft tissues, muscles and nerves, the temporomandibular joint and velopharyngeal functioning is of fundamental importance. It is worth considering particular situations in which osteodistraction is extremely helpful in maxillofacial surgery, for example in the construction of a neocondyle, in bone replacement during oncologic interventions, in obstructive sleep apnea correction and in hemi-mandibular reconstruction.

Osteodistraction in the craniofacial region

In the specific field of maxillofacial surgery, the use of osseous distraction is always more and more helpful not only in the rehabilitation of malformation pathologies, but also in the clinical situations that require bone deficit correction resulting from traumatic events and postsurgical effects, for example oncologic surgery. The reason for this versatility in the distraction protocols is, undoubtedly, due to the fact that, at present, they are valid surgical methods in alternative to or supporting maxillofacial surgery, since they are feasible from a very early age and they obtain a level of distraction that is often higher than with orthopedic devices or conventional surgery. There are multiple indications for osteodistraction and they range from cases of hyper- or hypodevelopment of the maxilla and mandible, of both their anteroposterior and transverse components, to complex syndromes such as cleft lip and palate. Even the clinical distraction of the upper and middle thirds of the cranium, through a coronal craniotomy, has been shown to be a safe surgical procedure and it allows, for example, the successful rehabilitation of adult patients suffering from hemifacial microsomia or craniosynostosis. With the continuous and constant evolution of the integration of osteodistraction principles in the rehabilitation of the craniofacial region, an ever-more effective interdisciplinary relationship between orthodontics and osteodistraction has been seen with growing interest. More often treatment plans are programmed in which the orthodontic and osteodistractive phases are integrated and complete each other, each supporting the other. Scientific and clinical progress achieved in this field in recent years, allows more and more refined therapeutic solutions to be programmed, permitting craniofacial operations and to repair an ankylotic dental arch or reposition osteointegrated implants to the most convenient bone sites.

Eagle's syndrome secondary surgical treatment. Report of a case

Eagle's Syndrome is reported to be the symptomatic calcification of the stylohyoid complex. Calcification of the stylohyoid ligament is a relatively common finding in the general population, however only a small percentage of these people presents symptoms. According to the kind of symptoms described by the patients it is possible to recognise two syndromes: the classic one, which occurs after a tonsillectomy, and stylo-carotid artery syndrome, which is independent from a tonsillectomy. The only effective treatment in symptomatic cases is the surgical shortening of the styloid process. The case presented underlines the problems due to the persistence of the calcified caudal portion of the stylohyoid ligament after a first surgical removal. A second surgical treatment is suggested for a complete resection of the calcified ligament which was causing the symptomatology complained by the patient. This patient had previously undergone surgical shortening of the stylohyoid ligament after he was diagnosed as having Eagle's Syndrome, of the styloid-carotid artery type. After a stylohyoidectomy, he still suffered from dysphagia, neck pain and scratching sensation when swallowing. Further surgical treatment was necessary, with the aim of removing the caudal portion of the ligament, which was causing the patient's symptoms. An extra-oral approach was used and, after surgery, the patient was completely relieved of the symptoms. Conventional and three-dimensional CT were performed after surgery, they showed the complete absence of the left calcified stylohyoid ligament.

Maxillary post-traumatic outcome correction. Literature review and personal experience. Part III: loss of maxillary substance (free flaps-distraction osteogenesis)

Revascularised free flaps retain dual vascularisation, both periosteal and medullary, undoubtedly present optimal survival and minimal re-absorption in view of the prevalence of osteogenetic rather than osteoclastic phenomena. A revascularised free bone flap involves the transfer of a certain amount of bone tissue, whether or not associated with a muscular, skin and/or facial component, with the features of an axial flap, dissecting the vascular stalk of the donor site and re-anastomosing both the arterial and the venous components on to recipient vessels in the site of the primary defect. The vessels in question measure only about 2-4 mm, so that micro-surgery techniques must be applied. For bone defects less than 6 cm, with upkeep of the mandibular or maxillary cortical bone and preservation of the soft tissues, with residual bone of at least 8 mm in height and 4 mm in thickness, alveolar distraction may represent a valid alternative to bone grafts, at the same time as ensuring an increase of the alveolar bone and intraoral soft tissues involved in the distraction process.

Treatment of small hepatocellular carcinoma with percutaneous ethanol injection: a validated prognostic model

OBJECTIVE

Percutaneous ethanol injection may prolong the survival of patients with small hepatocellular carcinoma associated with cirrhosis. The aim was to identify prognostic factors of survival and of local recurrence, as well as separate new lesions.

METHODS

We performed Cox regression analysis in 115 consecutive patients with hepatocellular carcinoma (81 Child-Pugh class A, 34 Child-Pugh class B) treated by percutaneous ethanol injection. The validity of the model was tested by comparing predicted and observed survival in 105 independent patients from an external series.

RESULTS

Overall survival rates were 89%, 63%, and 43% at 1, 2, and 3 yr, respectively. The 1-, 2-, and 3-yr survival rates were 96%, 78%, and 63%, respectively, for Child-Pugh class A patients and were 73%, 35%, 12%, respectively, for Child-Pugh class B. The albumin level was the only independent variable significantly associated with survival (p < 0.0001). The 3-yr rate of appearance of separate new lesions and local recurrence were 41% and 23%, respectively. The survival predicted by the model agreed with that observed in the independent patients.

CONCLUSIONS

Survival of patients with hepatocellular carcinoma treated by percutaneous ethanol injection is related to baseline albumin level. The high rate of recurrence (both local and distant) points out the palliative role of this therapy.

Problem-based learning: why curricula are likely to show little effect on knowledge and clinical skills

OBJECTIVES

A recent review of problem-based learning's effect on knowledge and clinical skills updated findings reported in 1993. The author argues that effect sizes (ES) seen with PBL have not lived up to expectations (0.8-1.0) and the theoretical basis for PBL, contextual learning theory, is weak. The purposes of this study were to analyse what constitutes reasonable ES in terms of the impacts on individuals and published reports, and to elaborate upon various theories pertaining to PBL.

DESIGN

Normal theory is used to demonstrate what various ESs would mean for individual change and a large meta-analysis of over 10 000 studies is referred to in identifying typical ESs. Additional theories bearing upon PBL are presented.

RESULTS

Effect sizes of 0.8-1.0 would require some students to move from the bottom quartile to the top half of the class or more. The average ES reported in the literature was 0.50 and many commonly used and accepted medical procedures and therapies are based upon studies with ESs below 0.50.

CONCLUSIONS

Effect sizes of 0.8-1.0 are an unreasonable expectation from PBL because, firstly, the degree of changes that would be required of individuals would be excessive, secondly, leading up to medical school, students are groomed and selected for success in a traditional curriculum, expecting them to do better in a PBL curriculum than a traditional curriculum is an unreasonable expectation, and, thirdly, the average study reported in the literature and many commonly used and accepted medical procedures and therapies are based upon studies having lesser ESs. Information-processing theory, Cooperative learning, Self-determination theory and Control theory are suggested as providing better theoretical support for PBL than Contextual learning theory. Even if knowledge acquisition and clinical skills are not improved by PBL, the enhanced work environment for students and faculty that has been consistently found with PBL is a worthwhile goal.

Implant placement in the maxillary tuberosity: the Summers' technique performed with modified osteotomes

The maxillary tuberosity region is becoming increasingly involved in preprosthetic surgery as part of a comprehensive implant treatment planning. The lower success rates in osteointegrated implant placements seen in the posterior regions of the upper maxilla as compared to the anterior regions of the jaws, most often come from bone quality types and the presence of the maxillary sinus. In order to overcome these limitations and obtain a successful result in such a demanding area, several authors suggest that long implants (15.0 to 20.0 mm long) should be placed in the maxillary tuberosity region as an alternative to sinus floor elevation. The challenges frequently associated with the surgical placement of "maxillary tuberosity implants" (MTI), can be reduced through a "Ridge Expansion Osteotomy" (REO) procedure as described by Summers (1994). This indeed improves the recipient bed bone quality and causes no bone overheating. In order to improve this technique performed for MTI, in co-operation with Ing. Albanese G, authors have developed different prototypes of modified osteotomes. A case report using these new instruments is presented. Clinical and radiographic evaluations are obtained.

Collaboration and peer review in medical schools' strategic planning

The management of medical schools has never been so difficult, but can be facilitated by using a well-developed, broadly accepted strategic plan. While the concept of strategic planning has been reasonably well accepted by both faculty and leaders at most medical schools, using the strategic plan to allocate resources has proved to be a challenge. Achieving "buy-in" by all parties involved can help meet this challenge and can be critical to the success of strategic planning and management. The authors describe the collaborative planning process that the University of Wisconsin Medical School used to develop its 1998-2000 strategic plan. This unique effort culminated in using a peer-review process--similar to that used by the National Institutes of Health (NIH)--and developing criteria to select a limited number of program priorities. This selection occurred after a school-wide process to solicit strategic program proposals had taken place. Over 130 faculty from most departments throughout the school helped develop and revise the strategic plan. There was frequent communication and engagement with faculty at all levels, which was important in gaining the faculty's acceptance and, indeed, endorsement of the process and its outcomes. Because the process was effective in achieving consensus about the school's strategic priorities, it enabled the school to reach a firmer end-point and implementation plan than had been possible with the previous strategic plan. It also identified important weaknesses in some areas of the medical school; the resulting attention to those areas will help strengthen the school. Finally, the process moved much more swiftly than the previous effort. The authors recommend that such an approach be used by other medical schools, and be carried out before a school implements mission-aligned budgeting and management of its fiscal resources.

Vertical distraction of a free vascularized fibula flap in a reconstructed hemimandible: case report

The authors report a case of vertical distraction osteogenesis of a free revascularized fibula flap used to reconstruct an hemimandible lost as a result of a gunshot injury. The reconstruction procedure and the distraction protocol are described; clinical and radiological results are presented. The vertical discrepancy between the fibula and the native right hemimandible was corrected.

Students are not customers: a better model for medical education

The author argues that the student-as-customer model of medical education has many failings that result in interactions that are educationally dysfunctional. Ten "pathologies" resulting from the adoption of this model are presented (e.g., "The student-customer model seduces students into believing that they know what is best for them"). Part of the reason for the unprofessional conduct often demonstrated by students and faculty alike may be a result of the influence of this model on medical education and the consequent inappropriate empowerment of students in the role of customers, the diminishment of faculty in the role of workers who provide instruction, and the view that instruction is the service or product of medical education. The author proposes a new model of medical education in which faculty are managers of instruction, students are learning workers, the product is successful learning, and the customers are faculty, residency supervisors, patients, managed care organizations, and society. The implications of this new model are profound and are described in terms of Deming's 14 principles for achieving quality in business. The author maintains that the proposed model is the critical first step in clarifying and identifying the proper roles of all those involved in the medical education process, which in turn will diminish or eliminate the pathologies that currently plague medical education and lead to the achievement of real quality.

Rating educational quality: factors in the erosion of professional standards

Changes in the health care environment are putting increasing pressure on medical schools to make faculty accountable and to document the quality of the medical education they provide. Faculty's ratings of students' performances and students' ratings of faculty's teaching are important elements in these efforts to document educational quality. This article discusses selected research related to factors affecting raters' judgments, analyzes how changes in the health care environment are influencing such judgments, and links these influences to the system that upholds professional standards. Ratings are known to have a positive bias (generosity error), provide limited discrimination, and often fail to document serious deficits. The potential sources of these problems relate to the mechanics of the rating task, the system used to obtain ratings, and factors affecting rater judgment. As managed care demands reduce the time faculty have for teaching, as system-wide disincentives to provide negative ratings proliferate, and as social engineering challenges, such as the Americans with Disabilities Act, impose differential standards for students, the natural tendency to avoid giving negative ratings becomes even harder to resist. Ultimately, these forces compromise the capability of faculty to uphold the standards of the profession. The author calls for a national effort to stem the erosion of those standards.

Gross pathologic types of hepatocellular carcinoma in Italy

The prevalence and independent predictors of the different macroscopic types of hepatocellular carcinoma (HCC) were assessed in 1,073 unselected patients of 14 hospitals in Italy from May 1996 to May 1997. Solitary HCC was the most common cancer type (44.6%), followed by multinodular (44.2%), diffuse (8.4%) and massive (2.8%) types. After adjustment for the influence of confounders by multiple logistic regression analysis, Child-Pugh grades B and C were found to be independent predictors of multinodular (odds ratio, OR, 2.0; 95% confidence interval (CI) = 1.5-2.6) and diffuse (OR 2.6; 95% CI = 1.6-4.4) HCC types. These findings indicate that the majority of HCC cases are not detected at a potentially treatable stage. Delayed detection of HCC is associated with a higher likelihood of the multinodular or diffuse gross pathologic type.

An institutionally funded program for educational research and development grants: it makes dollars and sense

Lack of funding for educational research and a paucity of researchers with academic credibility have been identified as the key issues facing the medical education research enterprise. The authors argue that institutionally supported programs for educational research and development grants can help to address these issues. This report (1) describes the general rationale for having such programs, (2) describes the development of such a program at the University of Wisconsin School of Medicine, and (3) reports the outcome of the first three cycles of awards. The program outcomes include 28 intramurally funded projects, a 200% increase in funds for educational research from local sources other than the medical school, two new grants funded from extramural sources, one peer-reviewed publication, three presentations at national meetings, and six presentations at local meetings. Such a program is an excellent mechanism for demonstrating the administration's support for educational efforts and also provides a way to factor peer review of educational efforts into the faculty promotion process. The authors argue that these two reasons alone are sufficient to justify the development of such programs, although the outcomes at the University of Wisconsin also show compelling added value.

Successful peer review of courses: a case study

The authors describe their school's system of peer review for courses, established in 1988 to facilitate faculty evaluation and continual course and curriculum improvement. (The system has been temporarily suspended while the school's new curriculum becomes established.) They explain how the system was created and then report how faculty reviews of courses over the five-year operation of the system compared with students' reviews of the same courses. The faculty and students' ratings were in agreement 75% of the time. When not in agreement, the students' ratings tended to upgrade courses that were not very demanding, had easy grading, and emphasized clinical details, often at the expense of basic concepts and the big picture. The authors then document how the work of the peer review system favorably influenced the transformation of the school's curriculum. They also provide guidelines for the creation and operation of a course review process that uses faculty peers. The authors maintain that the peer review system worked because it was run by a committee of experienced and respected teachers who had been selected by their peers, the other faculty. Additional reasons for its success were that the school's faculty supported and respected the committee and its work, that course directors helped evaluate their courses, and that peer reviewers took their work seriously despite having no remuneration, and the clearly positive impact of the review system on faculty interaction, faculty-student interaction, and the reform of the curriculum.