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BACKGROUND: The aim was to quantify severe transient and persisting late term effects in our single institution head neck cancer (HNC) cohort treated with curatively intended intensity modulated radiation therapy (IMRT). Hypothesis was if a 2-year follow up (FU) is sufficient to estimate the long term tolerance in HNC irradiated in the IMRT era. METHODS: Between 01/2002-8/2012, 707/1211 (58%) consecutively treated IMRT patients met the inclusion criteria of a FU time >12 months and loco-regional disease control (LRC). 45% presented with loco-regionally advanced disease; 55% were referred for curative definitive IMRT (66Gy-72Gy in 30--35 fractions), 45% underwent postoperative IMRT (60-66Gy in 30--33 fractions). Systemic concomitant therapy was administered in 85%. Highly consistent treatment procedures were performed with respect to contouring processes, dose constraints, radiation schedules, and the use of systemic therapy. Grade 3/4 late term effects were prospectively assessed and analyzed with respect to subgroups at particular risk for specific late effects. RESULTS: Mean/median FU of the cohort was 41/35 months (15--124). 13% of the patients (92/707) experienced any grade 3/4 late effects (101 events in 92/707 patients), 81% in the first 12 months after radiation. 4% of all developed persisting late grade 3/4 effects (25 events in 25/707 patients). CONCLUSIONS: IMRT led to a high late term tolerance in loco-regionally disease free HNC patients. The onset of any G3/4 effects showed a plateau at 2 years. The question of the cervical vessel tolerance in disease free long time survivors is still open and currently under evaluation at our institution.

BACKGROUND: At the Clinic for Radiation Oncology at the Zurich University Hospital (UniversitätsSpital Zürich [USZ]), head-and-neck tumor (HNT) patients have been treated with intensity-modulated radiotherapy (IMRT) since 01/2002 (n 〉 800). This method causes less damage to normal tissues adjacent to the tumor, and thus it was possible in the head/neck region to markedly reduce the rate of osteoradionecrosis (ORN), in addition to reducing the rate of severe xerostomia. Based on these results, risk-adapted dental care (RaDC) was adopted by our clinic as the standard mode of pre-IMRT dental treatment. The guidelines as formulated by Grötz et al. were respected. ORN prophylaxis is one of the most important goals of pre-radiotherapy dental care, and the ORN rate is a measurable parameter for the efficacy of dental care, given a certain radiation technique. The aim of the present study was therefore to evaluate the efficacy of RaDC as reflected by the ORN rate of our IMRT patients. MATERIALS AND METHODS: IN August 2006, RaDC was clinically implemented and has been used for all HNT patients prior to IMRT since then. Before that (01/2002-07/2006), dental restorations were performed according to the usual procedure. RESULTS: The rate of grade-2 ORN was similar in the conventionally treated and RaDC groups (2% and 1%, resp.); grade-3 ORN had not occurred by the time the analysis was conducted. As expected, fewer extractions were performed in the RaDC cohort (no extractions in 47% of the RaDC/IMRT cohort vs. 27% in the IMRT cohort receiving conventional dental care). CONCLUSION: After considerably less invasive dental treatment, no higher-grade ORN occurred and no ORN-related jaw resections were required. Based on the present data, risk-adapted minimally invasive dental care is recommended before IMRT.

Objectives: A comparison of synthetic hydroxyapatite/silica oxide, xenogenic hydroxyapatite-based bone substitute materials with empty control sites in terms of bone regeneration enhancement in a rabbit calvarial four non-critical-sized defect model. Methods: In each of six rabbits, four bicortical calvarial bone defects were generated. The following four treatment modalities were randomly allocated: (1) empty control site, (2) synthetic hydroxyapatite/silica oxide-based (HA/SiO) test granules, (3) xenogenic hydroxyapatite -based granules, (4) synthetic hydroxyapatite/silica oxide -based (HA/SiO) test two granules. The results of the latter granules have not been reported due to their size being three times bigger than the other two granule types. After 4 weeks, the animals were sacrificed and un-decalcified sections were obtained for histological analyses. For statistical analysis, the Kruskal-Wallis test was applied (P<0.05). Results: Histomorphometric analysis showed an average area fraction of newly formed bone of 12.32±10.36% for the empty control, 17.47±6.42% for the xenogenic hydroxyapatite -based granules group, and 21.2±5.32% for the group treated with synthetic hydroxyapatite/silica oxide -based granules. Based on the middle section, newly formed bone bridged the defect to 38.33±37.55% in the empty control group, 54.33±22.12% in the xenogenic hydroxyapatite -based granules group, and to 79±13.31% in the synthetic hydroxyapatite/silica oxide -based granules group. The bone-to-bone substitute contact was 46.38±18.98% for the xenogenic and 59.86±14.92% for the synthetic hydroxyapatite/silica oxide-based granules group. No significant difference in terms of bone formation and defect bridging could be detected between the two bone substitute materials or the empty defect. Conclusion: There is evidence that the synthetic hydroxyapatite/silica oxide granules provide comparable results with a standard xenogenic bovine mineral in terms of bone formation and defect

BACKGROUND: The ameloblastic carcinoma is a rare malignant odontogenic tumor which rather occurs in the mandible than in the maxilla. Its rarity and in this context somewhat speculative histopathogenesis may account for diagnostic difficulties. Current classifications do not consider benign histopathological features at the primary and malignant features at the metastatic tumour site. Based on an evidence-based literature review, a recommendation for a novel classification is presented. METHODS: An evidence-based literature review over the last 60 years regarding ameloblastic carcinoma of the maxilla was conducted. RESULTS: An overall of 26 cases were found (mean age: 54.4 (5-83years); male to female ratio: 2.7 to 1). In 54% the primary diagnosis was ameloblastic carcinoma, 34.6% revealed pulmonary metastases, however, only in one patient cervical lymph node metastasis could be found. Whereas two cases did not reveal malignant histopathology at the primary, they revealed malignant features at their metastatic sites. Nineteen of 26 patients (73,1%) were controlled during a median follow-up time of 54,3 months (6 to 156 months); 6 patients died of disease after a median time of 62,7 months (7 to 156 months) after initial diagnosis. CONCLUSION: It is of utmost importance to be aware of that ameloblastomas may be capable to degenerate into a "malignant" disease with recurrence and metastasis. In addition to local long-term control, special attention should be paid to potential pulmonary involvement.

Since four years from now on more and more information about bisphosphonate induced osteonecrosis of the jaws is published not only in professional journals, but also in the mass media. The result is a growing uncertainty of patients, but also professionals in dealing with this group of medication. Usually bisphosphonates are prescribed for treatment of severe osteoporosis, but also for treatment of metastatic bone disease and tumor induced hypercalcemia. The following article gives information about bisphosphonates, bisphosphonate induced osteonecrosis of the jaws (BON) and potential risk factors. Additionally it shows the typical clinical picture, necessary diagnostic measures and informs about possible prevention strategies especially for dentists in daily practice.

Unilateral or bilateral dislocation of the TMJ is frequent. Usually it can be treated by the method described by Hippocrates. If conservative treatment (splint therapy, biofeedback, etc.) does not succeed related to recurrent fixed TMJ-dislocation, surgical therapy strategies become necessary. Above all mentally retarded or patients with neuromuscular disorders may necessitate surgical treatment. The two surgical main procedures are: 1. Removal of mechanical obstacles by reduction of the eminentia. 2. Creation of a mechanical obstacle towards the anterior condylar translation. The here presented case shows the treatment of a reccurent, fixed anterior TMJ-dislocation using a miniplate which enables a absolut heightening of the articular tubercle in a 76 years old lady with Morbus Alzheimer and Parkinson. Due to the high incidence of plate fractures, this well discribed therapy, known as miniplate eminoplasty, can not be considered as the treatment of choice for mandibular dislocation. It can be indicated in non-compliant patients or in patients with neuromuscular disorders or in the combination of both as in our case.

This article is aimed to inform about the recently performed adjustments of the established standard procedures for pre-radiotherapeutic dental care (GROTZ 2003; Shaw et al. 2000) on intensity modulated radiation therapy (IMRT) at the Department of Radiation Oncology, University Hospital Zurich (USZ).The adjustments described base on prospectively assessed results and clinical observations of more than 300 head and neck cancer patients treated with definitive or postoperative IMRT at the own institution. In order to explain the clinical differences between conventional radiation techniques and IMRT, a brief introduction section addresses characteristics of IMRT delivery, optimization of normal tissue sparing, and resulting improved normal tissue tolerance (Fig. 1a-c). In conclusion, careful adjustments of pre-treatment dental care as proposed (Tab. I) are recommended for IMRT patients. This requires close case-related interdisciplinary cooperation between the referring radiation oncologist and the dentist or dental care centre, respectively. The depicted sketches (Fig. 2) are thought to get completed by the radiation oncologist, in order to inform the dentist about topographic risk areas/levels for radiation-induced late effects.

BACKGROUND: Except for early T1,2 N0 stages, the prognosis for patients with oral cavity cancer (OCC) is reported to be worse than for carcinoma in other sites of the head and neck (HNC). The aim of this work was to assess disease outcome in OCC following IMRT.Between January 2002 and January 2007, 346 HNC patients have been treated with curative intensity modulated radiation therapy (IMRT) at the Department of Radiation Oncology, University Hospital Zurich. Fifty eight of these (16%) were referred for postoperative (28) or definitive (30) radiation therapy of OCC.40 of the 58 OCC patients (69%) presented with locally advanced T3/4 or recurred lesions. Doses between 60 and 70 Gy were applied, combined with simultaneous cisplatin based chemotherapy in 78%. Outcome analyses were performed using Kaplan Meier curves.In addition, comparisons were performed between this IMRT OCC cohort and historic in-house cohorts of 33 conventionally irradiated (3DCRT) and 30 surgery only patients treated over the last 10 years. RESULTS: OCC patients treated with postoperative IMRT showed the highest local control (LC) rate of all assessed treatment sequence subgroups (92% LC at 2 years). Historic postoperative 3DCRT patients and patients treated with surgery alone reached LC rates of approximately 70-80%. Definitively irradiated patients revealed poorest LC rates with approximately 30 and 40% following 3DCRT and IMRT, respectively.T1 stage resulted in an expectedly significantly higher LC rate (95%, n = 19, p < 0.05) than T2-4 and recurred stages (LC approximately 50-60%, n = 102).Analyses according to the diagnosis revealed significantly lower LC in OCC following definitive IMRT than that in pharyngeal tumors treated with definitive IMRT in the same time period (43% vs 82% at 2 years, p < 0.0001), while the LC rate of OCC following postoperative IMRT was as high as in pharyngeal tumors treated with postoperative IMRT (>90% at 2 years). CONCLUSION: Postoperative IMRT of OCC resulted in

The cemento-ossifying fibromas (COF) of the jaws are well circumscribed, generally slow-growing, benign lesions which enlarge in an expansive manner. On occasion, they may reach a large size and may result in considerable deformity. The histological pattern of these lesions varies with the stages. In most reported cases ossifying and cemento-ossifying fibromas occur as a solitary lesion. Multiple occurrence of such lesions is rare. The term"cemento-ossifying fibroma"is used to describe fibrous lesions containing calcifications with strong similarity between bone and cementum. Although WHO and some authors regard the cementifying fibroma (CF) as an odontogenic tumor and consider ossifying fibroma (OF) separately as non-odontogenic neoplasm, there is general agreement that CF and OF represent only histologic variants of the same lesion. The case of a 36-year old woman with multiple cemento-ossifying fibromas of the mandible and maxilla demonstrates the diagnostic procedures and a possible therapeutic strategy for this rare lesion.

BACKGROUND: Aim of this work was to assess loco-regional disease control in head and neck cancer (HNC) patients treated with postoperative intensity modulated radiation therapy (pIMRT). For comparative purposes, risk features of our series have been analysed with respect to histopathologic adverse factors. Results were compared with an own historic conventional radiation (3DCRT) series, and with 3DCRT and pIMRT data from other centres. Between January 2002 and August 2006, 71 patients were consecutively treated with pIMRT for a squamous cell carcinoma (SCC) of the oropharynx (32), oral cavity (22), hypopharynx (7), larynx (6), paranasal sinus (3), and an unknown primary, respectively. Mean and median follow up was 19 months (2-48), and 17.6 months. 83% were treated with IMRT-chemotherapy. Mean prescribed dose was 66.3 Gy (60-70), delivered with doses per fraction of 2-2.3 Gy, respectively. RESULTS: 2-year local, nodal, and distant control rates were 95%, 91%, and 96%, disease free and overall survival 90% and 83%, respectively. The corresponding survival rates for the subgroup of patients with a follow up time >12 months (n = 43) were 98%, 95%, 98%, 93%, and 88%, respectively. Distribution according to histopathologic risk features revealed 15% and 85% patients with intermediate and high risk, respectively. All loco-regional events occurred in the high risk subgroup. CONCLUSION: Surgery followed by postoperative IMRT in patients with substantial risk for recurrence resulted in high loco-regional tumor control rates compared with large prospective 3DCRT trials.