Immediate versus delayed implant placement of novel fully tapered tissue-level implants - A retrospective multicenter clinical study.

OBJECTIVES: To compare the clinical and radiological outcomes of novel fully tapered tissue-level implants in immediate implant placement (type 1) versus late implant placement (type 4) for the first time. MATERIALS AND METHODS: For this clinical study, 318 fully tapered tissue-level implants in 65 patients were inserted immediately (n = 68 implants) or late (n = 250 implants) in two different centers. Implant survival and success rates and marginal bone levels were analyzed. RESULTS: After a mean follow-up of 12.0 ± 5 months, implant survival rates were 97.8% for all implants. No statistically significant difference in implant survival rates between type 1 and type 4 could be detected (98.5% vs 97.6%, HR 0.70, 95%-CI 0.084-5.81). Neither for implant length (HR 0.53, 95%-CI 0.055-5.08) nor for implant width (HR 0.27, CI 0.028-2.55), a significant influence on implant survival could be detected. Type of used biomaterial for filling the gap and immediate loading showed no effect on implant survival. Mean marginal bone loss was 0.02 ± 0.05 mm for type 1 and 0.04 ± 0.1 for type 4. CONCLUSIONS: Within the limitations of this retrospective study and the short follow-up, the results demonstrated comparable high survival and success rates and stable marginal bone levels for type 1 and type 4 placement of this novel tissue-level implant (no clinical trial registration as retrospective study design).

Platelet-rich fibrin for rehydration and pre-vascularization of an acellular, collagen membrane of porcine origin.

OBJECTIVES: Pre-vascularization of the collagen membranes with autologous platelet concentrates is a standard procedure in oral and maxillofacial surgery. This study analyzed the possible interaction of an acellular collagen membrane of porcine origin (NM) with platelet-rich fibrin (PRF) regarding its rehydration protocol with differences in pH values and effect on angiogenesis. MATERIALS AND METHODS: NM was analyzed alone and combined with solid PRF by plotting or co-culturing with injectable PRF. Different media (venous blood, buffer solution with a fixed pH value of 7, saline solution, and injectable PRF) were used to analyze the influence on pH value during rehydration. Chorion allantois membrane assay (CAM) was applied to check pro-angiogenic effects after 24, 48, and 72 h, followed by immunohistochemical analysis. RESULTS: Rehydration in injectable PRF showed acidity over time (p < 0.05). A definite pro-angiogenic effect of NM alone was found regarding neo-vessel formation supported by the respective light microscopically analysis without significant differences to PRF alone (p > 0.005). This pro-angiogenic effect could not be exaggerated when NM was combined with liquid/solid PRF (each p > 0.005). CONCLUSIONS: Rehydration with liquid PRF of the collagen membrane results in acidity compared to a saline solution or patient's blood. The significant pro-angiogenic potential of the membrane alone resulted in enhanced neo-vessel formation that could not be optimized with the addition of PRF. CLINICAL RELEVANCE STATEMENT: Using injectable PRF for rehydration protocol of the collagen membrane leads to acidosis that can ultimately optimize wound healing. Differences in the physio-mechanical interplay of collagen matrices and autologous platelet concentrates must result in clinical algorithms if pre-vascularization can maximize outcomes.

Dental implants in patients with head and neck cancer-A systematic review and meta-analysis of the influence of radiotherapy on implant survival.

PURPOSE: The purpose of this meta-analysis was to compare implant survival in irradiated and non-irradiated bone and to investigate potential risk factors for implant therapy in oral cancer patients. MATERIAL AND METHODS: An extensive search in the electronic databases of the National Library of Medicine was performed. Systematic review and meta-analysis were conducted according to PRISMA statement. The meta-analysis was performed for studies with a mean follow-up of at least three and five years, respectively. RESULTS: The systematic review resulted in a mean overall implant survival of 87.8% (34%-100%). The meta-analysis revealed a significantly higher rate of implant failure in irradiated bone compared to non-irradiated bone (p < .00001, OR 1.97, CI [1.63, 2.37]). The studies also showed that implants placed into irradiated grafted bone were more likely to fail than those in irradiated native bone (p < .0001, OR 2.26, CI [1.50, 3.40]). CONCLUSION: Even though overall implant survival was high, radiotherapy proves to be a significant risk factor for implant loss. Augmentation procedures may also increase the risk of an adverse outcome, especially in combination with radiotherapy. CLINICAL RELEVANCE: The treatment of patients receiving radiotherapy of any form requires precise individual planning and a close aftercare. Implants should be placed in local bone rather than in bone grafts, if possible.

Surgical safety checklists for dental implant surgeries-a scoping review.

OBJECTIVES: In both elective surgeries and aviation, a reduction of complications can be expected by paying attention to the so-called human factors. Checklists are a well-known way to overcome some of these problems. We aimed to evaluate the current evidence regarding the use of checklists in implant dentistry. METHODS: An electronic literature search was conducted in the following databases: CINHAL, Medline, Web of Science, and Cochrane Library until March 2022. Based on the results and additional literature, a preliminary checklist for surgical implant therapy was designed. RESULTS: Three publications dealing with dental implants and checklists were identified. One dealt with the use of a checklist in implant dentistry and was described as a quality assessment study. The remaining two studies offered suggestions for checklists based on literature research and expert opinion. CONCLUSIONS: Based on our results, the evidence for the use of checklists in dental implantology is extremely low. Considering the great potential, it can be stated that there is a need to catch up. While creating a new implant checklist, we took care of meeting the criteria for high-quality checklists. Future controlled studies will help to place it on a broad foundation. CLINICAL RELEVANCE: Checklists are a well-known way to prevent complications. They are especially established in aviation, but many surgical specialties and anesthesia adopt this successful concept. As implantology has become one of the fastest-growing areas of dentistry, it is imperative that checklists become an integral part of it.

Halitosis in Oral and Maxillofacial Surgery Patients - a Pilot Study.

BACKGROUND: Halitosis is a relatively inhomogeneous pathology with an extremely high prevalence in the population. Potential risk factors for bad breath include bacterial decomposition of organic material as well as numerous general and systemic diseases. The aim of the present study was to analyze whether certain subgroups of oral and maxillofacial surgery patients have a higher risk of halitosis. Further the impact of halitosis on the patient's quality of life was ascertained. METHODS: A total of 127 oral and maxillofacial patients aged between 19 and 86 years were enrolled in this study. On account of their underlining disease, patients were divided into five different investigation groups. The dental examination comprised tongue coating, periodontal screening index (PSI), gingival index (GI), PI (plaque index), DMF-T values as well as non-stimulated saliva flow rates. Halitosis was monitored both organoleptically according to Rosenberg and instrumentally by means of a Halimeter®, which records the volatile sulfur compounds (VSC values in ppm). Patients were further asked to fill out questionnaires regarding their medical history and oral hygiene, oral health (OHIP-14), and quality of life (BDI-II). RESULTS: Halitosis values, which were recorded by a Halimeter® correlated with the objective Rosenberg golden standard method. Furthermore, halitosis values correlated with elevated PSI, GI, and DMF-T values as well as the degree of tongue coating. Patients with oral cancer showed significantly higher VSC values compared to all other groups. No difference in VSC values could be found between all other patient groups. CONCLUSIONS: The Halimeter® could be validated as a suitable method for determining halitosis in oral and maxillofacial patients. The significantly increased halitosis values in cancer patients as opposed to all other patient groups suggests the potential of halitosis VSC values as a potential screening method. The development of non-invasive breath tests for diagnosis could be subject of future research.

Treatment concepts of horizontally deficient ridges-A retrospective study comparing narrow-diameter implants in pristine bone with standard-diameter implants in augmented bone.

OBJECTIVES: To compare clinical and radiological outcomes of narrow-diameter implants (NDI) placed in pristine bone to standard-diameter implants placed in combination with horizontal bone augmentation procedures (SDI+A) for horizontally deficient alveolar ridges. MATERIAL AND METHODS: For this retrospective study, the outcome of 597 NDI (∅ 3.3 mm, 272 patients), inserted in pristine bone, were compared with 180 SDI (∅ 4.1 mm, 83 patients), inserted in combination with horizontal augmentation procedures. Oral health-related quality of life was assessed in patients available for recall. RESULTS: After a mean follow-up of 37.6 ± 40 months for the NDI and of 42.4 ± 49 months for the SDI+A, survival rates were 96.1% for NDI and 95.6% for SDI+A. Cumulative 5-year and 10-year implant survival rates were 94.3% and 92.2% for the NDI group and 97.0% and 88.3% for the SDI+A group, indicating no significant difference (p = .89). According to the criteria of Buser et al., an implant success rate of 84.3% was obtained for the NDI and an implant success rate of 81.3% for the SDI+A (p = .79). Regarding oral health-related quality of life, a similar and high patient satisfaction could be observed in both groups. CONCLUSIONS: NDI without augmentation procedures showed a similar clinical outcome as SDI in combination with augmentation procedures after a follow-up of more than 3 years. Therefore, NDI might be a reasonable alternative in cases of horizontal bone atrophy (no clinical trial registration as patient inclusion started 2003).

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.

Biofunctionalization of porcine-derived collagen matrices with platelet rich fibrin: influence on angiogenesis in vitro and in vivo.

OBJECTIVES: Porcine-derived collagen matrices (CM) can be used for oral tissue regeneration, but sufficient revascularization is crucial. The aim of this study was to analyze the influence of platelet-rich fibrin (PRF) on angiogenesis of different CM in vitro and in vivo. MATERIALS AND METHODS: Three different CM (mucoderm®, jason®, collprotect®) were combined with PRF in a plotting process. Growth factor release (VEGF, TGF-ß) was measured in vitro via ELISA quantification after 1,4 and 7 days in comparison to PRF alone. In ovo yolk sac (YSM) and chorion allantois membrane (CAM) model, angiogenic potential were analyzed in vivo with light- and intravital fluorescence microscopy after 24 h, then verified with immunohistochemical staining for CD105 and αSMA. RESULTS: Highest growth factor release was seen after 24 h for all three activated membranes in comparison to the native CM (VEGF 24 h: each p < 0.05; TGF-ß: each p < 0.001) and the PRF (no significant difference). All activated membranes revealed a significantly increased angiogenic potential in vivo after 24 h (vessels per mm2: each p < 0.05; branching points per mm2: each p < 0.01; vessel density: each p < 0.05) and with immunohistochemical staining for CD105 (each p < 0.01) and αSMA (each p < 0.05). CONCLUSIONS: PRF improved the angiogenesis of CM in vitro and in vivo. CLINICAL RELEVANCE: Bio-functionalization of CM with PRF could easily implemented in the clinical pathway and may lead to advanced soft tissue healing.

A clinical study on the 6-year outcomes of immediately loaded three implants for completely edentulous mandibles: "the all-on-3 concept".

The objective of the current study was to demonstrate the 6-year clinical and radiological treatment outcomes of the technique performed by immediately loading of three implants (single straight in the mid-line and two tilted distal implants) for the management of total edentulous mandibles and introduce a simple decision matrix for selection of the most appropriate protocol in cases with insufficient length of the interforaminal area. Re-assessments were performed over a total observation period of 6 years after surgery via measurement of bone resorption around implants, bleeding on probing, plaque accumulation, periodontal probing depth, bite force measurements and oral health impact profile. A total of 29 patients (45% women and 55% men) with a mean age of 65 ± 6 years enrolled in the study. 14 patients received an acryl-based bridge as definitive prosthetic restoration and 15 patients received a ceramic-based restoration. Both during the immediate loading phase and during the 6-year follow-up, there was no implantation loss. Regardless of the implant position, all implants showed continuous bone loss over the observation time. The bone loss around dental implants during observation period was only maximum 1.0 ± 1 mm and it remained well within the limits for 'success' according to the 2007 Pisa consensus (< 2 mm). The plaque index showed no significant fluctuations between the implant positions and the individual examination times. The approach described herein might help the surgeon by avoiding unnecessary loss of bone strength, selecting implant sites, and establishing the biomechanical advantage of increased A-P spread for immediate function.

Proinflammatory cytokines as serum biomarker in oral carcinoma-A prospective multi-biomarker approach.

BACKGROUND: Inflammation and cell-mediated immunity have a key role in different stages of carcinogenesis. The aim of this prospective study was to assess serum levels of proinflammatory cytokines interleukin-6 (IL-6), interleukin-8 (IL-8), soluble interleukin-2 receptor (sIL-2R), tumor necrosis factor alpha (TNF-α), and MHC class I polypeptide-related sequence B (MICB) in patients with oral premalignant lesion (OPL), oral squamous cell carcinoma (OSCC), and healthy controls in a multi-biomarker approach as a potential diagnostic and prognostic tool for OSCC. MATERIAL AND METHODS: A total of 205 patients (81 with OSCC, 75 with OPL, and 49 healthy controls) were included in this prospective study. Cytokine concentrations were measured by commercial enzyme linked immunoassay and chemiluminescence immunoassay. RESULTS: IL-6, IL-8, and sIL-2R were significantly elevated in OSCC patients compared to healthy controls and to OPL patients. Higher T-Grade (>T2) and positive lymph node involvement resulted in significantly higher IL-6 values (P < .001 and P = .037). IL-6 serum values ≥5 pg/mL (n = 45) and sIL-2R serum values ≥623 U/mL (n = 19) indicated a significant lower survival rate compared to OSCC patients with low IL-6 (n = 36) and sIL-2R values (n = 62, P = .023 and P = .026). ROC and classification tree analyses identified the combination of IL-6 and IL-8 as diagnostic markers with good diagnostic accuracy. CONCLUSION: In conclusion, IL-6, IL-8, and sIL-2R are strongly associated with OSCC oncogenesis and IL-6 and sIL-2R seem to be promising and potent biomarkers for evaluating patients' prognosis.

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.

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.

Comparison of conventional twist drill protocol and piezosurgery for implant insertion: an ex vivo study on different bone types.

OBJECTIVE: The aim of this ex vivo study was to compare implant insertion procedures using piezosurgery and conventional drilling in different qualities of bone. Implant bed preparation time, generated heat, and primary implant stability were analyzed. MATERIAL AND METHODS: Fresh ex vivo porcine bone block samples (cancellous, mixed, and cortical bone) were obtained. The bone quality was quantified by ultrasound transmission velocity (UTV). Each bone sample received three implants of the same diameter using each of the techniques of piezosurgery and conventional twist drills. Time for preparation was taken and the temperature while performing the osteotomy was measured using infrared spectroscopy. The primary implant stability after osteotomy was measured using resonance frequency analysis (RFA) and extrusion torque (ET). ANOVA with post hoc Tukey test was carried out to compare the values for the three different groups. RESULTS: The UTV values strongly correlated with the density of the bone samples. There was a significant increase in time (threefold, P < 0.05 [302 s vs. 122 s in cortical bone]) but no difference in the temperature for the piezo group (~37°C in cortical bone). Regardless of the osteotomy technique, there was a statistically significant increase in RFA and ET values in implants inserted in cancellous bone (RFA: piezo 77, drill 76; ET: piezo 22, drill 21), mixed bone (RFA: piezo 85, drill 86; ET: piezo 105, drill 61), and cortical bone (RFA: piezo 90, drill 87; ET piezo 184, drill 79) samples, respectively (P < 0.05). In between the different osteotomy groups, there was no difference in the RFA values but significant higher ET values in mixed/cortical bone samples in favor for the piezosurgery group. CONCLUSION: Piezosurgery and conventional implant bed drilling procedure do have similar mechanical outcomes regarding primary stability with high RFA values, but the preparation does need more time for piezosurgery group, so that piezosurgery might be a valuable tool in only very specific cases for implant bed preparation.

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.

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.

Significance of endothelial progenitor cells (EPC) for tumorigenesis of head and neck squamous cell carcinoma (HNSCC): possible marker of tumor progression and neovascularization?

OBJECTIVES: Angiogenesis and neovascularisation plays a crucial role for tumorigenesis and tumor progression in head and neck squamous cell carcinoma (HNSCC). The aim of our study was to investigate the neovascularization capacity by endothelial progenitor cells (EPC) in tumor patient as a possible predictor for tumor progression and tumor stage. MATERIALS AND METHODS: Therefore, we investigated the cell number and biologic activity by cell migration and colony-forming ability of EPC. Cells were isolated from the peripheral venous blood of 79 patients who suffer HNSCC in different stages of disease. Thirty-three healthy individuals served as the control group. RESULTS: Significantly increased biological activities were reflected by expression of the migration rate (1027 ± 1510) in comparison to the control group (632 ± 269) and the clonal potency measured by colony-forming unit (CFU) (tumor patients (19.7 ± 12.3) vs. control group (10.84 ± 4.8)). To determine whether or not EPC number can be used as a valid prognostic marker for clinical outcome of tumor patients, we furthermore compared a "high EPC-number-subgroup" (HI) with a "low EPC-number-subgroup" (LO) in a Kaplan-Meier survival curve. The HI-subgroup shows herein clearly a worse outcome. CONCLUSIONS: Our findings indicate a possible pathway for EPC to play a critical role in the vasculogenesis and consequently in the progression of HNSCC. CLINICAL RELEVANCE: Our findings could serve as possible predictors for the neovascularisation potential in HNSCC tumor patients.

Lactate as a predictive marker for tumor recurrence in patients with head and neck squamous cell carcinoma (HNSCC) post radiation: a prospective study over 15 years.

OBJECTIVES: Lactate as a key regulator of the glycolytic phenotype has been recently described in fueling tumor growth and metastatic spread in head and neck squamous cell carcinoma (HNSCC). However, in context of tumor recurrence following adjuvant radiation, the underlying mechanisms remain uncertain. We therefore investigate the role of lactate towards radioresistance in HNSCC in this prospective study for the first time in vivo. MATERIALS AND METHODS: Herein, we analyzed biopsies of primary squamous cell carcinoma after surgery and adjuvant irradiation in 17 patients. Tumor tissue levels of ATP, glucose, and lactate were detected using induced metabolic bioluminescence imaging (imBI) and correlated with clinical data within an observation period of up to 15 years. RESULTS: High amounts of lactate levels in tumors of HNSCC are significantly negatively correlated with overall patient survival. Moreover, high expression of lactate in a primary tumor site is significantly correlated with tumor recurrence post radiation, whereas ATP and/or glucose showed no such correlation. CONCLUSION: Lactate can be seen not only as a waste product of altered glycolytic metabolism but also as a key master of malignancy as well as resistance mechanism towards irradiation. CLINICAL RELEVANCE: High expression of lactate levels in tumor tissue, obtained by metabolic bioluminescence imaging, may therefore serve as a predictor for overall and recurrence-free survival and could represent a future biomarker in the validation of adjuvant irradiation.

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.

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.

Comparative evaluation of thickness of jaw-closing muscles in patients with long-standing bilateral temporomandibular joint ankylosis: a retrospective case-controlled study.

OBJECTIVES: The aim of the study was to compare the thickness and cross-sectional area (CSA) of masseter and medial pterygoid muscles in young patients with long-standing bilateral temporomandibular joint ankylosis (bTMJA) in relation to controls. METHODS: Axial sections of computed tomography scans of patients with bTMJA from two tertiary care university hospitals were reviewed from 1995 to 2010 and compared to age- and sex-matched controls. The outlines of masseter and medial pterygoid muscles corresponding to a predefined reference plane were traced onto acetate paper. The thickness and CSA of the muscles were calculated using an image-analyzing software and calibrated according to the scale provided in the CT scan slides. RESULTS: Out of a total of 167 cases of temporomandibular joint ankylosis (TMJA), 15 fulfilled the inclusion criteria. The mean thickness and CSA of masseter and medial pterygoid muscles in cases of bTMJA were 19.4 mm (SD 2.3), 734.9 mm(2) (SD 156.7), 11.53 mm (SD 1.35), and 267.4 mm(2) (SD 65.35), respectively. For the control group, respective values were 10.5 mm (SD 1.8), 430.1 mm(2) (SD 66.8), 9.2 mm (SD 1.2), and 254.6 mm(2) (SD 45.7). There was a statistically significant increased thickness and CSA of the muscles in cases of bTMJA as compared to control as evaluated by Mann-Whitney U test. CONCLUSIONS: The results show that thickness and CSA of masseter and medial pterygoid muscles in patients with bTMJA were larger as compared to controls. This may suggest that, muscular hyperactivity, may be a cofactor in the pathogenesis of TMJA. CLINICAL SIGNIFICANCE: Although temporomandibular joint ankylosis is one of the most restrictive musculoskeletal disorder in the maxillofacial region, there is little information on the form and function of jaw muscles in this condition. This study evaluates thickness and cross-sectional areas of jaw elevator muscles and indicates that muscle hyperactivity might be associated with ankylosis, thereby providing a probable hypothesis on the etiopathogenesis of this condition.