The Efficiency of a Learning Software Compared to e-Books in Dental Education.

OBJECTIVES: Due to time-consuming curricular and extracurricular activities, students in dentistry and medicine can profit from efficient learning strategies. One strategy could be the preparation with individually designed educational software that embed different multimedia sources. The aim of this study was to determine the efficiency of such a program compared with an e-book similar to a traditional textbook. MATERIALS AND METHODS: Dentistry students of the Johannes Gutenberg-University of Mainz passed an entrance multiple-choice test on the topic of odontogenic tumors and were then randomized into two groups. Afterward, both groups had 14 days to study on the topic of odontogenic tumors either with a learning software or an e-book. A final exam was then taken and the two groups were compared. STATISTICAL ANALYSIS: A least significant difference post hoc analysis comparing the group average values was performed. The level of significance was p <0.05. RESULTS: Seventy-one students took part in the study. While students from the first and second clinical semester showed significantly better results and improvements with the e-book, an opposite effect was observed in students from the third and fifth clinical semester with significantly better results and improvements with the software. CONCLUSION: Depending on the clinical experience and knowledge, a multimedia educational software can help students in dentistry to enhance efficiency in the preparation for exams.

Oral Squamous Cell Carcinomas Developing from Oral Lichen Planus: A 5-21 year Retrospective Study.

Background and Aims: There is insufficient data regarding clinical characteristics, relapse rates, as well as lymph node metastasis of squamous cell carcinomas of the oral cavity (OSCC) developing from oral lichen planus (OLP-OSCC). The aim of this retrospective study was to evaluate clinical characteristics, as well as relapse, recurrence and survival rates of OLP-OSCC. Methods: In a retrospective monocenter analysis, all consecutive patients with an OSCC treated in the time period 1st January 2000-December 31 2016 were reviewed. All patients with OSCC developing from OLP/OLL (oral lichenoid lesions) were identified and analyzed for epidemiological data, risk profile, location of primary tumor, pTNM classification, lymph node metastasis, primary therapy, recurrence, and outcome. Results: A total of 103 patients (45%♂/ 55%♀) with an average age of 62 ± 14 year were included in this study. At the time of initial diagnosis, 17% (n = 18) of patients had cervical metastases (CM) whereas only 11% (11 patients) displayed advanced tumor sizes (T > 2). T-status (p = 0.003) and histopathological grading (p = 0.001) had an impact on the incidence of CM. 39.6% of the patients developed a relapse after an average of 24 months with a mean of two recurrences per patient. Advanced tumor size had a significant impact on the 5 year overall survival and was associated with disease-free survival of the patients (p < 0.001, respectively p = 0.004). Conclusion: Although initial lymph node metastases were not more frequent, more aggressive recurrence patterns compared to OSCC were seen for OLP-OSCC. Therefore, based on the study results, a modified recall for these patients is suggested.

The role of diabetes mellitus on the formation of severe odontogenic abscesses-a retrospective study.

OBJECTIVES: To analyze the correlation of diabetes mellitus and hyperglycemia with severe odontogenic abscesses. MATERIALS AND METHODS: Records of all patients in the Department of Oral and Maxillofacial Surgery of the Medical Center of the Johannes Gutenberg-University who underwent inpatient treatment for severe odontogenic abscesses between 2010 and 2016 were evaluated retrospectively regarding diabetes anamnesis, maximum and fasting blood sugar count, and duration until discharge. In order to compare the numbers to a general maxillofacial group, all patients who received inpatient treatment in 2013 for any diagnosis other than an abscess of the head and neck region were analyzed as well, and the numbers were correlated. RESULTS: In total, 977 abscess patients were found in the analyzed period. 7.0% of the patients had a known diagnosis of diabetes mellitus type II and 0.6% of type I. Correlation with the general group showed that abscesses were significantly more likely in diabetics as well as patients with abnormal maximum and fasting blood sugar counts. These patients also needed significantly longer inpatient treatment. CONCLUSIONS: Diabetics and patients with abnormal glucose tolerance show significantly higher numbers of severe odontogenic abscesses and might therefore benefit from earlier escalation of antibiotic medication. CLINICAL RELEVANCE: Severe odontogenic abscesses are one of the most frequent diagnoses in maxillofacial practice. Adjusting the therapeutic approach for diabetics or patients with abnormal blood sugar counts might help to prevent the development of abscesses.

Factors accelerating recurrences and secondary tumors in cutaneous squamous cell carcinoma.

To investigate factors that affect and also decrease the duration for recurrences and secondary tumors in cSCC. A retrospective study was conducted for all patients who were treated for a cSCC of the head and neck between 2009 and 2016. Anamnestic as well as epidemiological and histological data were noted and correlated with the occurrence of recurrences and secondary cancers. The duration between surgery and these events was used to determine if histological factors accelerate their occurrence. The highest risk for recurrences was seen in patients with previous skin cancers (RR 3.23). Histological ulceration (p = 0.003) and grading (p = 0.031) of the tumor were found as significant factors accelerating the time to relapse. Surrounding chronic precancerotic lesions (p < 0.001) and poor tumor grading (p = 0.035) were found as significant factors accelerating the time until a secondary cSCC was observed. Known risk factors increase not only the risk for a cSCC but also for recurrences. Specific histologic findings can help to adjust follow-up intervals to identify recurrences and secondary tumors at an early stage as these were shown to decrease the duration for a further event.

Sentinel lymph node biopsy in malignant melanoma of the head and neck.

BACKGROUND: The aim of this retrospective study was to investigate sentinel lymph node biopsy in patients with head and neck melanoma. MATERIALS AND METHODS: Patients who underwent SLNB between 2010 and 2016 were comprised. Epidemiological, radiological, and surgical data were collected and compared to histological findings. Patients who underwent primary complete lymph node dissection were excluded. RESULTS: 74 patients underwent SLNB during this period. The most common tumor localizations were the cheek (20.4%) and ears (20.4%). Overall, 256 sentinel lymph nodes (SLN) were detected and removed, most frequently in Robbins-levels IIA and IIB as well as in the surrounding of the parotid gland. 12.3% of the SLN showed a microscopic or macroscopic metastasis. In preoperative imaging all lymph nodes with macroscopic metastasis were described as suspect but only 4 of 11 lymph nodes with microscopic metastases were described as such. CONCLUSIONS: SLNB is an especially good procedure for the diagnosis of microscopically metastases as disease status is an important diagnostic and prognostic factor in early-stage melanoma patients. However, due to the complex lymphatic system in head and neck melanoma, a short follow-up interval is necessary in order to prevent delayed diagnosis of a nodal recurrence due to a false-negative SLN.

Diabetes and hyperglycemia as risk factors for postoperative outcome in maxillofacial surgery.

BACKGROUND: Aim of this study was to investigate the frequency of complications in maxillofacial surgery in-patients in correlation to diabetes mellitus or a pathologically altered glucose metabolism. MATERIALS AND METHODS: All patients' electronic health records were analyzed retrospectively. Diabetes mellitus anamnesis, the treatment regime, blood glucose levels, and the duration of inpatient treatment were recorded. Glucose readings ≥200 mg/dL measured at any time and fasting glucose levels of ≥110 mg/dL were defined as hyperglycemic. Noted complications were infection, dehiscence, swelling, and necrosis. RESULTS: 8.7% out of 1374 patients had a known diabetes diagnosis. 13.0% had high fasting glucose and 11.4% aberrant maximum glucose readings. Complications did not occur more often in patients with a previously known diabetes but more often in patients with high maximum blood glucose levels. Of these patients, only 56.3% were known diabetics. CONCLUSIONS: Diabetes mellitus does not necessarily lead to higher frequency of complications in surgical patients. Moreover, patients with well-controlled diabetes seem to have a similar outcome compared to nondiabetics. Hyperglycemia however has an important impact on treatment outcome.

Coincidence of mandibular fractures with isolated posterior maxillary sinus fractures.

BACKGROUND/AIM: There are no data available to show whether there is a relationship between mandibular fractures and isolated fractures of the posterior and/or lateral walls of the maxillary sinus. The aim of this study was to determine whether there is a coincidence between these fracture patterns. METHODS: Four hundred large volume cone beam computed tomography scans (CBCT) of patients with a fracture of the mandible between 2008 and 2013 were analyzed retrospectively. Patients with multiple midfacial fractures were excluded. The radiographic findings were correlated with epidemiological and clinical data of the patients such as gender, age, treatment methods, or complications. RESULTS: The most frequent fracture sites of the mandible were the jaw angle, the parasymphysis region, and the condyle. Nineteen of the 400 patients (4.75%) had an isolated fracture of the lateral and/or posterior maxillary sinus. Odds-ratio analysis revealed a high tendency for significant correlation of condylar process fractures with isolated maxillary sinus fractures. Chi-square test demonstrated a P-value near statistical significance (P=.054). No other fracture site of the mandible could be associated with an isolated fracture of the maxillary sinus. CONCLUSION: A condylar process fracture of the mandible after trauma without any further injury of the midface may be associated with an isolated fracture of the lateral and/or posterior maxillary sinus.

Outcome and cervical metastatic spread of squamous cell cancer of the buccal mucosa, a retrospective analysis of the past 25 years.

OBJECTIVES: Because of the low proportion of squamous cell carcinomas (SCCs) of the buccal mucosa within the carcinomas of the oral cavity in the Western population, data concerning metastatic pattern are sparse. Therefore, this retrospective study is focusing on the occurrence of cervical metastases (CM) and the overall outcome of this tumor entity. MATERIALS AND METHODS: From January 1988 to October 2013, 113 patients were treated in the Department of Oral and Maxillofacial Surgery, Mainz, for an oral SCC of the cheek. Metastatic pattern and clinical parameters that are possibly associated with an increased risk for CM as well as overall outcome were analyzed. RESULTS: The average follow-up was 48 months (range: 1-248 months). A total of 55 (49%) patients were female and 58 (51%) male, with an average age of 65 ± 13 years (♀68 ± 14 years; ♂63 ± 11 years). In total, 55% of the patients either smoked and/or consumed alcohol. In total, 34% of the patients had a stage III or IV tumor, with overall 23% having CM at the time of diagnosis. During the follow-up, 50% (n = 56) of the patients developed a relapse after 12 months (median). Tumor size (P = 0.002*) and grading (P < 0.001*) are significantly associated with the occurrence of CM. Metastases (P = 0.008*) and advanced tumor size (P = 0.018) had an influence on the survival, whereas the relapse had no significant influence (P = 0.928). Five-year survival rate was 80%. CONCLUSIONS: SCC of the buccal mucosa shows aggressive behavior with a considerably high proportion of relapse. Since overall outcome is significantly decreased by the cervical metastatic pattern, a selective, ipsilateral neck dissection for this patient group is recommended as the primary management.

Cervical metastases behavior of T1-2 squamous cell cancer of the oral mucosa.

OBJECTIVES: The clinical management of the neck of patients with early-stage oral squamous cell cancer (OSCC) is still controversially discussed in the current literature. This study analyzes histo-clinical factors influencing the occurrence of cervical lymph node metastases (CM). MATERIALS AND METHODS: In a retrospective mono-center study, patients with a primary T1-2 OSCC between 2000 and 2014 were analyzed regarding histo-clinical parameters possibly influencing the CM rate and the outcome. RESULTS: Two hundred eighty-five patients (66 %) were male and 146 female (44 %), with a mean age of 60 ± 12 years at the time of diagnosis. Seventy-seven percent showed a positive risk profile (nicotine/alcohol) and 69 % underlying diseases. Forty-four percent of the patients were staged as T2 (30 % with CM). Advanced tumor size (T1 vs. T2) and grading (G1-2 vs. G3) were statistically significantly (p < 0.001) associated with the occurrence of CM. The localization within the oral cavity, age, gender, risk profile, or underlying diseases had no influence on CM occurrence. During the follow-up, tumor size (p = 0.001), CM (p < 0.001), and tumor relapse (p < 0.001) were significantly associated with a worse outcome. CONCLUSIONS: Early-stage OSCC showed aggressive lymphatic metastatic behavior that depends on the size and the grading of the tumor. CLINICAL RELEVANCE: A watch-and-wait policy as the primary management for cN0 may likely be inferior to a selective neck dissection for this patient group and should only be considered for very small tumors with a good differentiation.

Sentinel lymph node biopsy in T1/T2 squamous cell carcinomas of the tongue: A prospective study.

Commonly used staging procedures often cannot predict the absence of cervical metastases (CM) in squamous cell carcinomas (SCCs) of the oral cavity. Due to the high incidence of occult CM in numerous N0 cases in the clinic, an elective neck dissection (ND) is performed. The sentinel lymph node biopsy (SNB) is a common concept in the modern surgical therapy of malignancies. The present study evaluates the applicability of this concept for T1/T2-SCC of the tongue. In a prospective clinical study, 10 consecutive patients with T1/T2-SCC of the tongue and cN0 necks, were enrolled. Following sentinel lymph node (SLN) scintigraphy, all patients underwent SNB with a γ-probe and a subsequent ND. SNB specimens were compared with histopathological assessments of surgical specimens from the ND. A total of 5 female and 5 male patients (mean age, 52 years; women, 62 years; men, 42 years), with a median follow-up time of 33.5 months (range, 10-40 months), were treated. All patients presented with detectable SLNs. In 7 cases, the SLN(s) and the residual ND were negative for CM. In 3 cases, the SLN(s) were positive without further CM in the other neck nodes. Furthermore, 1 patient showed additional CMs after 10 months in the contralateral neck and lung metastasis after 18 months, but none at the time of the initial treatment. The concept of an SNB appears to be applicable to the management of the cN0 neck in small SCC of the tongue. The role of SNB in the management of SCC requires further investigation by prospective trials with larger patient numbers.

Association between eruption state of the third molar and the occurrence of mandibular angle fractures.

BACKGROUND/AIM: Fractures of the mandible, especially the mandibular angle, are one of the most frequent types of injuries of the facial skeleton. In many cases, a retained third molar can be found in the line of the fracture. However, it remains unclear whether a relationship between third molars and mandibular angle fractures exists. MATERIALS AND METHODS: Patients with isolated or combined fractures of the lower jaw between January 2001 and December 2007 were analyzed retrospectively. Electronic health records were investigated regarding the types of mandibular fractures, and panoramic radiographs were reviewed concerning the existence of third molars. In addition, a systematic review was performed to compare the findings of this study with existing data. RESULTS: Six hundred and thirty-two patients were treated for mandibular fractures within the time frame. Two hundred and sixty-seven had a mandibular angle fracture. In 461 patients, panoramic radiographs were available, of which 45.6% did not have a third molar. About 3.8% were edentulous. There is a significant relationship between the existence of unerupted third molars and the occurrence of mandibular angle fractures (P < 0.001). No correlation exists for erupted third molars. CONCLUSIONS: Fractures of the mandibular angle are more likely to appear in patients with retained third molars which might be due to the reduced bone mass. Once the wisdom teeth have erupted, the bone structure is more solid and more resistant to external forces and the development of fractures.

Angiogenesis in the Development of Medication-Related Osteonecrosis of the Jaws: An Overview.

Medication-related osteonecrosis of the jaws (MR-ONJ) is one of the most relevant side effects of bisphosphonate therapy; it is clinically defined as a non-healing wound in combination with an avascular and necrotic jaw within ongoing bisphosphonate therapy or after completed bisphosphonate therapy. Different theories concerning the development of MR-ONJ have been reported, while the exact pathophysiology is still unknown. Recent studies have increasingly focused on angiogenesis and revascularization concerning MR-ONJ pathophysiology, which seems to be a relevant factor in the development of MR-ONJ and a possible and promising point of action for MR-ONJ prevention and therapy. Therefore, and with respect to the different aspects and specific forms of angiogenesis, the enclosed review summarizes the possible role of angiogenesis and revascularization in the pathophysiology of MR-ONJ. Special focus is given to the strong negative influence of bisphosphonates on progenitor and mature endothelial cells in vitro as well as on microvessel sprouting in vitro and in vivo, which might result in overall reduced wound healing of oral soft and hard tissues, and therefore in an exposed and avascular jaw from a clinical viewpoint. Further, it will be summarized whether and in what way the aspect of angiogenesis might be used for possible MR-ONJ prevention and therapy.

Diabetes Mellitus and Its Association to the Occurrence of Medication-Related Osteonecrosis of the Jaw.

To date there is no consensus on the role of diabetes in the development of medication-related osteonecrosis of the jaws (MR-ONJ). Therefore, this study aimed to investigate the prevalence of diabetes and pathological glucose metabolism in patients with MR-ONJ compared to the general population. All maxillofacial surgery inpatients in one year at our department were investigated regarding diagnosis, anamnesis, medication, and blood glucose readings. 1374 records were analyzed. 35 patients with MR-ONJ were identified. Diabetics accounted for 14.3%. No significant difference in the prevalence of known diabetes was found, except for pathological glucose metabolism in patients with MR-ONJ (p < 0.001). Diabetes does not necessarily promote the onset of MR-ONJ. Therefore, diabetes should not be considered as a standalone risk factor. On the contrary, hyperglycemia as a possible indicator for poorly managed or yet undetected diabetes is associated with MR-ONJ.

Traumatic dental injuries in a university hospital: a four-year retrospective study.

BACKGROUND: Traumatic dental injuries present complex injuries of the dentoalveolar system. Aim of this study was to investigate the frequency and patterns of traumatic dental injuries in a University dental emergency service over four years. METHODS: A retrospective investigation on all dental trauma patients presenting at the dental emergency service of the University Medical Center Mainz, Germany between 01/2010 and 12/2013 was conducted. Demographic data, the cause and type of trauma and the initial therapy were analyzed. RESULTS: Out of 16,301 patients, 1,305 patients (8 %; average age 14.7 years ±15.7; 60.1 % male, 39.9 % female) came due to trauma. 63.9 % of the traumas occurred on weekends. The most frequent reason for injuries was falls (54.6 %). No correlation could be found between the cause and the kind of trauma. In 48.6 % of the cases only one tooth was involved, in 33.5 % two. The permanent dentition was traumatized in 56.6 % of cases, the deciduous teeth in 41.1 %. The most frequently affected tooth was the central upper incisor (61.0 %). Hard-tissue injuries were significantly more frequent in the permanent dentition, while periodontal injuries were seen significantly more often in the deciduous dentition. CONCLUSION: Eight percent of all patients seeking help at the dental emergency service presented with trauma, meaning that dental traumatology is one of the major topics in emergencies. To improve the quality of care, further public education, expert knowledge among dental professionals and a well-structured emergency service are necessary.

Malignant lymphomas in the head and neck region--a retrospective, single-center study over 41 years.

OBJECTIVES: Non-Hodgkin lymphomas are malignant neoplastic proliferations of the immune system that can manifest as nodal or extranodal lymphomas. The aim of this study was to retrospectively investigate the site of occurrence of lymphomas in the head and neck area and to analyze the typical symptoms of patients who presented at an oral and maxillofacial surgical department. MATERIAL AND METHODS: All patient files from 1971 until 2012 from an Oral and Maxillofacial Surgery of a University were analyzed for the diagnosis non-Hodgkin lymphoma. Epidemiologic data and data regarding the localization of the malignant lymphoma were evaluated. RESULTS: 62 patients, 34 women and 28 men with a non-Hodgkin lymphoma in the head and neck area were treated in the 41 years analyzed. In 87% of the cases the lymphoma belonged to B-cell and in 12% to the T-cell lineage. The average age at the time of diagnosis was 67 years for women (n=34) and 56 years for men. With 22 patients each, the non-Hodgkin lymphoma was localized in either the soft tissues or osseous structures. In the remaining 18 cases, multiple structures were affected. In 33 patients no accompanying nodal manifestation was noticed. In 33 cases the lymphoma was located in the oral cavity. The most common symptoms were swelling (97%), pain (40%) and the existence of an ulcer (11%). CONCLUSION: In the present study more than 50% of the lymphomas were located in the oral cavity. Due to the unspecific symptoms, a histopathological verification of the diagnosis is crucial.

Concomitant dental injuries in maxillofacial fractures - a retrospective analysis of 1219 patients.

BACKGROUND/AIM: Traumatic dental injuries are frequently combined with maxillofacial fractures, but literature addressing this topic is rare. In a retrospective study, the frequency of dental lesions in inpatients with traumatic facial injuries was analyzed. MATERIAL AND METHODS: All patients referred to the Department of Oral and Maxillofacial Surgery of the University Medical Center of the Johannes Gutenberg-University Mainz for inpatient treatment due to facial fractures between January 2001 and December 2007 were analyzed regarding the type of fracture, its localization, and potential concomitant dental injuries. In addition a systematic review was performed to compare the findings of this study with existing data. RESULTS: Altogether 1219 facial trauma patients underwent inpatient treatment. 184 (15.87%) out of those had 451 injured teeth, and 4.9% were edentulous. The most frequent causes were assaults (25.1%), followed by falls (19.6%) and bike accidents (10.1%). Avulsion, especially of the upper incisors, occurred in most cases (27.9%). Assaults caused 1.29 dental fractures per patient, while traffic-related accidents led to three to four times higher injury-rates. CONCLUSIONS: With almost every sixth patient having at least one kind of dental injury, this study shows that a thorough anamnesis and examination of the dental status are absolutely necessary, especially in patients who suffered from high-speed impacts or collisions with low-resilience surfaces.

Analysis of reasons for osteonecrosis of the jaws.

PURPOSE: Osteonecroses of the jaws are caused by several reasons. Bisphosphonate-associated osteonecrosis of the jaws (BP-ONJ) is known since 2003 with an increasing incidence in the first years. Along with more knowledge about the pathophysiology, preventive strategies were implemented trying to reduce the incidence. The aim of this retrospective study was to analyze the frequency and overall proportion of BP-ONJ within the field of osteonecrosis. The data was compared to a similar study performed in 2005. METHODS: All patients with osteonecrosis or osteomyelitis treated in the period from April 2005 to July 2012 in the Oral and Maxillofacial Surgery at the University of Mainz, Germany, were analyzed. RESULTS: The reasons for osteonecrosis were bisphosphonates in 45 %, odontogenic or surgically induced osteonecrosis in 32 %, osteoradionecrosis in 17 %, traumas in 1 %, and in 4 % the reason remained unclear. The BP-ONJ became the most important factor for osteonecrosis. Its fraction in the years 2000-2005 was 10 % only. CONCLUSIONS: Although preventive strategies are implemented, the number of new cases got bigger. The implemented prevention strategies did not manage to reduce the overall number of new cases. Furthermore, the launch of other medications with a similar side effect on the jawbone as the BP-ONJ for bisphosphonates might influence the overall distribution of osteonecroses.

Intraoperative pelvic nerve stimulation performed under continuous electromyography of the internal anal sphincter.

PURPOSE: The aim of this animal study was to investigate the effect of intraoperative pelvic nerve stimulation on internal anal sphincter electromyographic signals in order to evaluate its possible use for neuromonitoring during nerve-sparing pelvic surgery. METHODS: Eight pigs underwent low anterior rectal resection. The intersphincteric space was exposed, and the internal (IAS) and external anal sphincter (EAS) were identified. Electromyography of both sphincters was performed with bipolar needle electrodes. Intermittent bipolar electric stimulation of the inferior hypogastric plexus and the pelvic splanchnic nerves was carried out bilaterally. The recorded signals were analyzed in its frequency spectrum. RESULTS: In all animals, electromyographic recordings of IAS and EAS were successful. Intraoperative nerve stimulation resulted in a sudden amplitude increase in the time-based electromyographic signals of IAS (1.0 (0.5-9.0) µV vs. 4.0 (1.0-113.0) µV) and EAS (p < 0.001). The frequency spectrum of IAS in the resting state ranged from 0.15 to 5 Hz with highest activity in median at 0.77 Hz (46 cycles/min). Pelvic nerve stimulation resulted in an extended spectrum ranging from 0.15 to 20 Hz. EAS signals showed higher frequencies mainly in a range of 50 to 350 Hz. However, after muscle relaxation with pancuronium bromide, only the low frequency spectrum of the IAS signals was still present. CONCLUSIONS: Intraoperative verification of IAS function by stimulation of pelvic autonomic nerves is possible. The IAS electromyographic response could be used to monitor pelvic autonomic nerve preservation.