Project description:BackgroundLittle is known about immediate implant placement in head and neck cancer patients. We studied implant survival and functional outcomes of overdentures fabricated on implants placed immediately after removal of the lower dentition during ablative surgery or preceding primary radiotherapy (RT).MethodsInclusion criteria were primary head and neck cancer, dentate lower jaw, and indication for removal of remaining teeth. Two implants to support a mandibular overdenture were placed immediately after extraction of the dentition during ablative surgery, or prior to starting primary radiotherapy. Standardized questionnaires and clinical assessments were conducted (median follow-up 18.5 months, IQR 13.3).ResultsFifty-eight implants were placed in 29 patients. Four implants were lost (implant survival rate 93.1%). In 9 patients, no functional overdenture could be made. All patients were satisfied with their dentures.ConclusionsCombining dental implant placement with removal of remaining teeth preceding head neck oncology treatment results in a favorable treatment outcome.
Project description:Introduction:The opioid epidemic has awakened educators to the insufficiency of training in the areas of pain management and substance use disorders within the curricula of health sciences schools. The University of Pittsburgh Center of Excellence in Pain Education created an online educational module focusing on factors contributing to the opioid epidemic and the role of robust interprofessional communication in avoiding common practitioner errors. Methods:The 1-hour module created by an interprofessional team comprised a pretest, video presentation featuring case vignettes, posttest, and learner satisfaction survey. The content of the module focused on four core concepts: (1) managing acute perioperative pain, (2) maximizing opioid safety, and (3) identifying and (4) managing suspected opioid abuse and diversion. Results:Data were obtained from 250 dental, pharmacy, and nursing students from the University of Pittsburgh who completed the module as part of their respective profession-specific curricula. Results collapsed across the three school-specific implementations indicated an average increase in knowledge test scores from pre- to posttest (Z = -8.82, p < .001). In addition, the learner satisfaction data revealed an overall positive response to the module, with students commenting that they enjoyed the module and felt it provided them with a valuable learning experience. Discussion:Learner outcomes and feedback suggest that our interprofessional team was successful in creating an effective learning module applicable to several health care professions, namely, pharmacy, dentistry, and nursing. Future studies might address the application of the knowledge gained to actual patient care.
Project description:Early diagnosis of agenesis of the mandibular second premolar (P2) enhances management of the dental arch in the growing child. The aim of this study was to explore the relationship in the development of the mandibular first molar (M1) and first premolar (P1) at early stages of P2 (second premolar). Specifically, we ask if the likelihood of P2 agenesis can be predicted from adjacent developing teeth. We selected archived dental panoramic radiographs with P2 at crown formation stages (N = 212) and calculated the likelihood of P2 at initial mineralisation stage 'Ci' given the tooth stage of adjacent teeth. Our results show that the probability of observing mandibular P2 at initial mineralisation stage 'Ci' decreased as both the adjacent P1 and M1 matured. The modal stage at P2 'Ci' was P1 'Coc' (cusp outline complete) and M1 'Crc' (crown complete). Initial mineralisation of P2 was observed up to P1 'Crc' and M1 stage 'R½' (root half). The chance of observing P2 at least 'Coc' (coalescence of cusps) was considerably greater prior to these threshold stages compared to later stages of P1 and M1. These findings suggest that P2 is highly unlikely to develop if P1 is beyond 'Crc' and M1 is beyond 'R½'.
Project description:Squamous cell carcinoma is the most common head and neck malignancy. It can occur in the mandible or maxilla without a preexisting oral mucosal lesion. Often, the clinical and radiographic presentation of SCC directs the clinician to favour malignancy over other pathological conditions. However, SCC may also mimic an infectious condition and therefore can pose a diagnostic challenge even for the most experienced clinicians. Herein, we report a case of mandibular squamous cell carcinoma in a 53-year-old male who presented with symptoms of right facial swelling, trismus, pain, and right-sided lip paresthesia. The patient underwent a surgical removal of the presumed infected third molar of the right mandible, but histopathological analysis of the associated soft tissue unexpectedly yielded squamous cell carcinoma. Given the biopsy-proven diagnosis, the patient received a mandibular resection of the tumor followed by primary reconstruction with a fibular free flap. Patients presenting with symptoms mimicking odontogenic infections should receive vigilant attention by clinicians with regard to the disease history, clinical signs, radiographic evidence, and decision for histopathological analysis. This is especially true in the context of impacted dentition, where malignancy must be considered when formulating a differential diagnosis.
Project description:PurposeThe gold-standard for reconstruction of large mandibular defects is the use of free flaps of vascularized autologous bone with the fibula as the preferred donor site. The use of "custom cutting guides" for this indication is becoming increasingly prevalent. But cost of the procedure averages around 2,500 dollars per patient excluding treatment and entails selection criteria. We think it is possible to standardize mandibular reconstructions from an anatomical mean. The objective of this study was to perform a mandibular morphometric analysis in order to obtain a set of "mean" measurements, which can be used by all surgeons interested in mandibular reconstruction.MethodsWe performed a morphometric analysis consisting of three-dimensional mandibular reconstructions of 30 men and 30 women. Several reference points were set and defined to evaluate specific lengths and angles of interest. We conducted an intra and inter-sexual descriptive analysis of measurements obtained.ResultsWe did not identify any major intra-sexual differences within each group. The gonial angle is more open in women and the measurements characterizing the basilar contour are more prominent in men. We did not identify any differences in alveolar region parameters.ConclusionThe results of this study constitute a morphological tool for surgeons, from bone graft to free flap. These results also confirm us that the use of «custom cutting guides» for mandibular reconstruction may be excessive. It is pertinent to examine the value of "custom made" mandibular reconstructions since the differences observed are of the order of millimeters.
Project description:The aim of this study was to make a comparison of the biomechanical behavior of four different internal fixation systems for mandibular angle fractures. A total of 40 polyurethane mandible replicas were employed with different fixation methods: group 1SP, one 2.0-mm four-hole miniplate; group 2PPL, two 2.0-mm four-hole parallel miniplates; group 3DP, one 3D 2.0-mm four-hole miniplate; and group 3DPP, one 3D 2.0-mm eight-hole miniplate. Each group was subjected to incisal or homolateral molar region loading. The load resistance values were measured at load application causing tip displacement of 1, 3, and 5?mm, and at the time at which the system achieves its maximum strength (MS). Means and standard deviations were compared among groups using analysis of variance and the Tukey test. Group 2PPL showed higher strength for all the displacements. For incisal loading, no statistically significant differences were found between groups 1SP, 3DP, and 3DPP. For molar loading, group 1SP and 3DPP showed statistically significant differences. For MS testing, group 1SP and 2PPL showed statistically significant differences in incisal loading; group 1SP and 3DP showed no statistically significant differences; and group 3DPP showed lower values of strength. Two parallel miniplates provide the most favorable mechanical behavior under the conditions tested.
Project description:PITX1 had a significantly higher expression in the lower teeth compared to the upper teeth and this difference in PITX1 level was more evident in the molars compared to premolars, consistent with data in mouse developing teeth. These show that the differential gene expression during odontogenesis can continue to exist in mature teeth. We suggest that an in vitro study of dental pulp cells should take the differential gene profiles between the mandibular and maxillary teeth into consideration. The knowledge about gene profiling and pathways in mature teeth paves a way to explore a more precise treatment approach in regenerative dentistry.
Project description:PurposeThis paper aims to evaluate the decision-making of wisdom teeth extractions (M3s extraction) and the epidemiological profile in the targeted population.Materials and methodThis was a prospective analysis study of 106 patients at our hospital august 20, 1953 specialist hospital, which is a referral center between January 1, 2020 and January 1, 2021. The patients are divided into 2 groups according decision-making of wisdom teeth removal based on scientific evidence if it's right or wrong.ResultsThere was no statistically significant difference between the groups regarding sex (P = 0.478), educational level (P = 0.718), or working status (P = 0.606). Furthermore, there was no statistically significant difference between the groups regarding general co-morbidity (P = 1.00) or oral history (P = 0.28). The mean age of the sample was 32.12 years (SD = 11.337 years, range = 17-70 years, median = 30 -years). We reported that only 28% of the third molars were surgically extracted. We included in Group (I), 81 patients who were treated for third molars removal which the decision-making was justified. In Group (II), 25 patients were treated for third molars removal which the decision-making was unjustified. Group (I) comprised 30 men and 51 women with a mean age of 30 years. Group (II) comprised 7 men and 18 women with a mean age of 27 years. The assessment of surgical outcomes (operating time, blood loss, hospital stay) showed no difference between groups.DiscussionMonitoring asymptomatic wisdom teeth appears to be an appropriate strategy. Regarding retention versus prophylactic extraction of asymptomatic wisdom teeth, decision-making should be based on the best evidence combined with clinical experience.76.4% had a reason for extraction that was justified. The reasons why extraction of the wisdom tooth was not justified in our study population was either: extraction for prophylaxis or in the case of asymptomatic non-pathological third molars; without scientific evidence.ConclusionThis subject, which is perpetually debated, requires updating dental health authorities by evaluating new conservative procedures.
Project description:Mandibular condylar fractures are among the most common facial fractures and some of the most difficult to manage. Opinions about the management of mandibular condylar fractures differ among surgeons. With the implementation of new technology, an increased understanding of fracture management, and better functional and morphological outcomes reported in the literature, open reduction and internal fixation is becoming many surgeons' preferred choice for the treatment of condylar fractures. Because surgical treatment of such fractures is complex, certain factors must be considered to achieve satisfactory outcomes. In this article, we summarise six key points in the management of mandibular condylar fractures: virtual evaluation of condylar fracture, a suitable surgical approach, good reduction, stable internal fixation, repair of the articular disc, and restoration of the mandibular arch width. We believe that these points will help to improve the prognosis of mandibular condyle fractures.
Project description:Dollo's law of irreversibility states that once a complex structure is lost, it cannot be regained in the same form. Several putative exceptions to Dollo's law have been identified using phylogenetic comparative methods, but the anatomy and development of these traits are often poorly understood. Gastrotheca guentheri is renowned as the only frog with teeth on the lower jaw. Mandibular teeth were lost in the ancestor of frogs more than 200 million years ago and subsequently regained in G. guentheri. Little is known about the teeth in this species despite being a frequent example of trait "re-evolution," leaving open the possibility that it may have mandibular pseudoteeth. We assessed the dental anatomy of G. guentheri using micro-computed tomography and histology and confirmed the longstanding assumption that true mandibular teeth are present. Remarkably, the mandibular teeth of G. guentheri are nearly identical in gross morphology and development to upper jaw teeth in closely related species. The developmental genetics of tooth formation are unknown in this possibly extinct species. Our results suggest that an ancestral odontogenic pathway has been conserved but suppressed in the lower jaw since the origin of frogs, providing a possible mechanism underlying the re-evolution of lost mandibular teeth.