Keyvan Sagheb

The prevalence of human papilloma virus (HPV) infections in oral squamous cell carcinomas: A retrospective analysis of 88 patients and literature overview

In addition to tobacco and alcohol consumption, the two main risk factors for oral squamous cell carcinoma (OSCC), recent studies have revealed infections with human papilloma virus (HPV) as an additional risk factor for OSCC development. In the field of head and neck malignancies, the prevalence of HPV infections in oropharyngeal cancer (OC) ranges in different studies up to 84%. While HPV infection is discussed as an independent risk factor in this region, its distinguished role in carcinogenesis of tumours localized to the oral cavity remains still uncertain. In this study, we analysed the HPV status in 88 consecutive patients with OSCCs localized anterior of the palatoglossal arch who were treated in the Department of Oral and Maxillofacial Surgery at the University Medical Center Mainz. The HPV status analysis was performed using DNA-PCR and immunostaining of p16 protein. The prevalence of HPV-positive OSCCs was about 6% (5 patients). In 3 patients the HPV subtypes 16/18 were found. No significant differences between the HPV positive and negative patients regarding age, gender, smoking and alcohol consumption, localization and TNM level could be detected. Contrary to other studies focussing on cancers of the lingual and palatine tonsil, the prevalence of HPV infections was much lower in the oral cavity. Therefore HPV infection might play a less important role in oral carcinogenesis.

Retrospective analysis of survival rates and marginal bone loss on short implants in the mandible

OBJECTIVES Short implants have become an interesting alternative to bone augmentation in dental implantology. Design of shorter implants and longer surveillance times are a current research issue. The goal of this study was to show the survival rates of short implants below 9 mm in the partly edentulous mandibular premolar and molar regions with fixed prosthetics. Marginal vertical and 2D bone loss was evaluated additionally. Different implant designs are orientationally evaluated. MATERIAL AND METHODS A total of 247 dental implants with fixed prosthetics (crowns and bridges) in the premolar and molar region of the mandible were evaluated; 47 implants were 9 mm or shorter. Patient data were evaluated to acquire implant survival rates, implant diameter, gender and age. Panoramic X-rays were analysed for marginal bone loss. RESULTS Average surveillance time was 1327 days. Cumulative survival rate (CSR) of short implants was 98% (1 implants lost) compared to 94% in the longer implants group without significance. Thirty-five of the short implants were Astratech (0 losses) and 12 were Camlog Screw Line Promote Plus (1 loss). Early vertical and two-dimensional marginal bone loss was not significantly different in short and regular length implant group with an average of 0.6 mm and 0.7 mm(2) in short implants over the observation period. CONCLUSIONS Within the limitations of this study, we conclude that short implants with a length of 9 mm or less have equal survival rates compared with longer implants over the observation period of 1-3 years.

Biomarkers in diagnosis and therapy of oral squamous cell carcinoma: A review of the literature

Oral squamous cell carcinoma (OSCC) represents the sixth most common cancer, accounting for 2-4% of all malignancies worldwide. The overall survival rate of less than 60% remains generally poor, with prognosis heavily relying on the TNM staging system. Tumor size as well as the presence and extent of lymph node metastases are widely recognized as the most important predictors. However, the underlying mechanisms that lead to an aggressive phenotype are not yet fully understood. Therefore, possible biomarkers are much in need to predict prognosis, to help individualize therapy approaches, and to overcome possible resistance mechanisms. Despite a multitude of recently published biomarkers for OSCC, there is still an ongoing debate regarding their implementation in the clinical workflow. Thus, a systematic literature search via PubMed was performed to update the current literature with the latest evidence. In total, 128 studies were included and over 100 different biomarkers evaluated with reference to their influence of survival, tumor recurrence, advanced grading and lymph node metastasis. In this review, we highlight the important molecular mechanism underlying possible markers in tissue, blood or saliva samples for OSCC. As a major result, no clinical trials could be obtained to prove clinical importance of the validated predictors for survival, tumor recurrence, lymph node metastasis and therapy resistance. Therefore, further clinical investigations are much needed.

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.

Clinical and Radiological Long‐Term Outcome of a Tapered Implant System with Special Emphasis on the Influence of Augmentation Procedures

BACKGROUND AND PURPOSE Tapered implant designs aim to improve primary stability and implant survival in soft bone. However, respective clinical long-term data are scarce. Therefore, a clinical and radiological evaluation of the long-term success of a transgingival-supracrestal inserted tapered implant system with special emphasis on the influence of augmentation procedures was conducted. MATERIAL AND METHODS In a retrospective study design, all in the Department of Oral and Maxillofacial Surgery of the University Medical Centre, Mainz, Germany, between May 2002 and March 2012, placed tapered implants (Straumann TE®, Basel, Switzerland) were analyzed. In this time period, a total of one hundred ninety-seven tapered implants were inserted in 90 patients. For patients available for clinical recall, success criteria according to Albrektsson and Buser were evaluated. RESULTS The in situ rate was 96.3% after an average time in situ of 62 ± 31 months. In one hundred twenty-seven sites, bone augmentation procedures were performed. Hereof, 96 sites were sinus augmentation procedures and 31 sites were alveolar ridge augmentations. For patients with sinus augmentation procedures, implant survival was 97.9% and for patients with alveolar ridge augmentations, implant survival was 93.5% after 5 years, indicating a higher implant survival for sinus augmentation, however not statistically different (p = .194). Implant diameter and timing of implant placement had no significant impact on implant survival (p > .05). Mean marginal bone loss was -0.50 ± 1.54 mm for patients receiving maxillary sinus augmentation and -1.16 ± 1.13 mm for patients with alveolar ridge augmentations, indicating a lower marginal bone loss in patients receiving maxillary sinus augmentation (p = .046). Implant success rates ranged between 88% and 92% after a mean follow-up of 6 years. CONCLUSIONS Within the limits of the retrospective character of this study, the tapered soft tissue level implant showed especially in maxillary sinus augmentation promising long-term survival and success rates and a low peri-implant bone resorption compared with the literature.

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 from1971 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.

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.

Acceptance of E-Learning Devices by Dental Students

Background E-Learning programs and their corresponding devices are increasingly employed to educate dental students during their clinical training. Objective Recent progress made in the development of e-learning software as well as in hardware (computers, tablet PCs, smartphones) caused us to more closely investigate into the habits of dental students in dealing with these learning techniques. Methods Dental students during their clinical training attended a survey compiled in cooperation with biostatisticians. The questionnaire probands were asked to complete based on previous surveys of similar subjects, allowing single as well as multiple answers. The data, which were obtained with respect to the learning devices students commonly employ, were compared with their internet learning activities. Results The e-learning devices utilized are of heterogeneous brands. Each student has access to at least one hardware type suitable for e-learning. All students held mobile devices, about 90 percent employed laptops, and about 60 percent possess smartphones. Unexceptional all participants of the survey acknowledged an unlimited internet access. In contrast, only 16 percent of students utilized tablet PCs. A detailed analysis of the survey outcome reveals that an increasing use of mobile devices (tablet PC, smartphone) facilitates internet learning activities while at the same time utilization of computers (desktop, laptop) declines. Conclusions Dental students overwhelmingly accept e-learning during their clinical training. Students report outstanding preconditions to conduct e-learning as both their access to hardware and to the internet is excellent. Less satisfying is the outcome of our survey regarding the utilization of e-learning programs. Depending of the hardware employed only one-third to barely one-half of students comprise learning programs.

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.

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.