Florian Probst

Tooth extraction in patients receiving oral or intravenous bisphosphonate administration: A trigger for BRONJ development?

INTRODUCTION Scientific debate outlines tooth extraction as a potential trigger for the onset of bisphosphonate-related osteonecrosis of the jaw (BRONJ). Therefore, the aim of this study was to investigate the outcome of tooth extractions in patients receiving bisphosphonate therapy. PATIENTS AND METHODS A retrospective cohort study was performed on patients with a history of oral or intravenous bisphosphonate administration and tooth extraction between 2007 and 2013 in a single university hospital oral and maxillofacial surgical unit. In all patients, extractions were performed according to the guidelines of the German Society of Oral and Maxillofacial Surgery. The outcome variable was the onset of typical BRONJ signs during postoperative follow-up. RESULTS In 72 subjects (53 female, 19 male; mean age 67.5 years) receiving oral (n = 27) and/or intravenous (n = 45) bisphosphonates due to malignant tumor (n = 43) or osteoporosis (n = 29), 216 tooth extractions were performed. The mean duration of intake was 36.2 months. In 67 out of 72 patients (93.1%) and 209 out of the 216 extraction sites the postoperative course was uneventful and the wounds healed without complications. Three of the 72 patients (4.2%) developed osteonecrosis of the jaw in four of the 216 extraction sites (1.9%). Duration and route of administration, oral hygiene and steroid intake were identified as potential risk factors for the development of BRONJ. CONCLUSION Tooth extraction in patients receiving bisphosphonates can be performed in a safe and predictable way, even in high-risk patients, when performed according to established guidelines. It is not tooth extractions themselves, but rather prevailing infectious conditions that may be a key risk factor for the development of BRONJ.

MatrixMANDIBLE Preformed Reconstruction Plates—A Two-Year Two-Institution Experience in 71 Patients

PURPOSE To evaluate handling, complication rates, clinical and treatment outcomes of the MatrixMANDIBLE Preformed Reconstruction Plates (MMPRPs), in particular with regard to the frequency of fatigue fractures and operative time. PATIENTS AND METHODS A cohort of 71 subjects with an indication for a load-bearing osteosynthesis of the mandible was enrolled in the present study. The indications for plate use were defects due to tumor, trauma, or osteonecrosis. The outcome variables were fitting accuracy, application time, and postoperative complications, defined as plate exposure, loosening of plates or screws, plate fracture, and orocutaneous fistulas. Additionally, the feasibility of a transoral approach was tested. RESULTS The sample included 71 subjects with a mean age of 54.8 ± 15.0 years, including 43 men (60.6%). MMPRPs could be placed in 70 of the 71 patients. In 10 patients a transoral approach for plate application was successfully performed. The mean time investment to contour the plates was 13.1 minutes. The fitting accuracies of the nonbendable sections were satisfying. No plate fracture was observed within an average follow-up period of 11.8 months. Postoperative complications occurred in 19 (27.1%) of the 70 patients. Plate removal was required in 11 (15.7%) of 70 patients. CONCLUSIONS The results of the present study suggest that the use of MMPRPs coincides with a reduced operative time and a minimized risk of fatigue fractures. Thus, MMPRPs seem to be a useful standard device in a scope of indications for load-bearing osteosynthesis of the anterolateral division of the mandible, additionally facilitating a transoral approach for application.

Clinicopathologic Features of Oral Squamous Cell Carcinoma: Do They Vary in Different Age Groups?

PURPOSE To analyze clinicopathologic parameters of oral squamous cell carcinoma (OSCC) in different age groups. We hypothesized that clinical and pathologic parameters of OSCCs will vary in different age groups. MATERIALS AND METHODS A retrospective cohort study was performed. All patients who were treated for a primary manifestation of OSCC at a single institution from 2001 to 2012 were reviewed and allocated to predefined age groups (predictor variable) as follows: young (≤40 years), middle-aged (40-80 years), and very elderly (≥80 years). The following outcome variables were recorded: demographic parameters, classic risk factors, tumor location and size, neck node involvement, histopathologic and therapeutic details, and association with human papillomavirus (HPV). The descriptive statistics were computed. Parametric and nonparametric tests were used for additional analysis. The significance level was set at P < .05. RESULTS We reviewed 739 patients and identified 11 (1.4%) young (mean age 34.2 ± 2.8 years) and 17 (2.3%) very elderly patients (mean age 83.1 ± 1.2 years). The predilection site for OSCC was the oral tongue (63%) in young patients, the floor of the mouth (52%) in middle-aged patients, and the alveolar process (60%) in very elderly patients. One patient in the young group (9%) and 8 patients in the very elderly group (47%) had been exposed to risk factors; however, all of the examined middle-aged patients had had such exposure. The association of OSCC with HPV was distributed equally among the age groups. No age-related differences in the histopathologic parameters of OSCC were found. CONCLUSIONS The features of OSCC that vary at different ages are the anatomic predilection site and the association with classic risk factors. HPV was not an age-related independent risk factor for OSCC development in the present study.

Etiology and clinical characteristics of symptomatic unilateral maxillary sinusitis: A review of 174 cases.

The purpose of the study was to analyze the causative pathology associated with symptomatic unilateral maxillary sinusitis requiring surgical treatment. A retrospective review of all patients that have been treated surgically for unilateral symptomatic maxillary sinusitis between 2006 and 2013 at a single institution was performed. Demographic, anamnesis, clinical, radiological, microbiological and histological data were gathered and analyzed. The patients were allocated into groups depending on the underlying cause of the disease. Descriptive and inferential statistics were computed (level of significance: p ≤ 0.05). The study sample was composed of 174 patients (72 female; 102 male) with a mean age of 52.7 years (SD 16.9). Most cases (130; 75%) were triggered by odontogenic pathology following dentoalveolar surgical interventions (83/130 patients; 64%). Other etiological factors for odontogenic unilateral sinusitis were periapical (23/130 cases; 18%) and periodontal pathology (13/130 cases; 10%). Rhinogenic factors for sinusitis were detected in 13 patients (7.5%) and dental implant-associated unilateral maxillary sinusitis was diagnosed in nine patients (5.2%). Four patients (2.3%) had undergone previous sinus augmentation surgery. A leading cause for the sinus infection could not be identified in 18 patients (10%) who all had a history of midfacial surgery. Medication-related osteonecrosis of the jaw (8) and squamous cell carcinoma (2) were incidental findings. There were no differences in the clinical appearance of the disease with respect to its etiology. Odontogenic causes for maxillary sinusitis must be considered especially in unilateral cases. Maxillary dental implants may induce symptomatic unilateral maxillary sinusitis.

Patient-specific reconstruction plates are the missing link in computer-assisted mandibular reconstruction: A showcase for technical description

INTRODUCTION Preoperative planning of mandibular reconstruction has moved from mechanical simulation by dental model casts or stereolithographic models into an almost completely virtual environment. CAD/CAM applications allow a high level of accuracy by providing a custom template-assisted contouring approach for bone flaps. However, the clinical accuracy of CAD reconstruction is limited by the use of prebent reconstruction plates, an analogue step in an otherwise digital workstream. TECHNICAL REPORT In this paper the integration of computerized, numerically-controlled (CNC) milled, patient-specific mandibular plates (PSMP) within the virtual workflow of computer-assisted mandibular free fibula flap reconstruction is illustrated in a clinical case. Intraoperatively, the bone segments as well as the plate arms showed a very good fit. Postoperative CT imaging demonstrated close approximation of the PSMP and fibular segments, and good alignment of native mandible and fibular segments and intersegmentally. Over a follow-up period of 12 months, there was an uneventful course of healing with good bony consolidation. CONCLUSION The virtual design and automated fabrication of patient-specific mandibular reconstruction plates provide the missing link in the virtual workflow of computer-assisted mandibular free fibula flap reconstruction.

Transoral Open Reduction and Fixation of Mandibular Condylar Base and Neck Fractures in Children and Young Teenagers—A Beneficial Treatment Option?

PURPOSE To evaluate the possible benefits of open surgery, endoscopically assisted reduction and fixation using a transoral route was used in a selected series of pediatric patients with displaced condylar base and neck fractures. PATIENTS AND METHODS A cohort of 6 patients (1 male and 5 female; age range, 7 to 15 yr; mean, 13.4 yr) with displaced condylar base and neck fractures (n = 9) were included. Inclusion criteria were age younger than 16 years, fracture of the condylar base or neck, and displacement of the fracture by at least 45°. Fractures were classified using conventional radiography, cone-beam computed tomography, or computed tomography. Patients underwent transoral endoscopically assisted open reduction and fixation using miniplate osteosynthesis. Postoperatively, patients were followed clinically and radiographically for 18 months. RESULTS Complete follow-up varied from 18 to 35 months (median, 24.5 months). All patients showed normal occlusion and pain-free unrestricted function of the temporomandibular joint at 3, 6, 12, and 18 months postoperatively. There were no signs of incomplete remodeling or deformation of the condyles. CONCLUSION Transoral endoscopically assisted surgical treatment of severely displaced condylar base and neck fractures in children and young teenagers offers a reliable solution to preclude the sequelae of closed treatment, such as altered morphology and functional disturbances, eliminates visible scars, and lowers the risk of facial nerve damage compared with open reduction using an extraoral approach.

A concept for scaffold-based tissue engineering in alveolar cleft osteoplasty

BACKGROUND Alveolar cleft osteoplasty (ACO) using autologous bone grafts, is used worldwide as a standard treatment in the management of patients with clefts. Harvesting of the various autologous bone grafts is accompanied by considerable donor-site morbidity. Use of scaffold-based tissue engineering in ACO could potentially provide treatment options with decreased, or no donor-site morbidity. This study aims to demonstrate the technical and cell biological feasibility of using scaffold-based tissue engineering in ACO. MATERIAL AND METHODS Pre-existing cone-beam computed tomography scans were used for 3D printing of custom-made scaffolds (tricalcium phosphate-polyhydroxybutyrate (TCP-PHB)) according to the individual geometry of the alveolar bone in patients with clefts. The scaffolds were seeded with commercially available human mesenchymal stem cells (hMSCs). Cell survival and cell proliferation was monitored by live-dead assay, scanning electron microscopy (SEM) and WST-1 assay. The osteogenic differentiation of hMSCs on the scaffolds was evaluated by alkaline phosphatase (ALP) assay. RESULTS The custom-made scaffolds were nearly identical to the size and shape of the digital master. Approximately 91% of the subsequently applied mesenchymal stem cells could be seeded on the rails. We could demonstrate successful cell proliferation by a factor of 5-7 over the first 3 weeks. SEM showed a pore-border growth of the hMSCs on the scaffolds after 3 weeks of cell proliferation. The successful osteogenic differentiation of the scaffold-seeded cells could be demonstrated. CONCLUSION The concept of scaffold-based tissue engineering provides great potential as an alternative for the present gold standard of autologous bone grafts in ACO. The treatment causes less morbidity and is less invasive for managing young patients with cleft alveolar bone defects. Further in vivo studies and clinical trials are needed to demonstrate the advantages of this novel treatment for ACO in the clinical setting.

Ibandronate treatment of diffuse sclerosing osteomyelitis of the mandible: Pain relief and insight into pathogenesis.

PURPOSE Diffuse sclerosing osteomyelitis of the mandible (DSO) is a rare and poorly understood disease. Current treatment protocols, including steroid or analgesic medication and corticotomies, show poor or frustrating outcome results and are accompanied by potentially severe side effects. The aim of this study was to determine whether there is a beneficial role of infusions with nitrogen-containing bisphosphonates (ibandronate) in acute conditions of DSO. MATERIAL AND METHODS Eleven patients were enrolled in the study. In acute conditions of treatment-resistant DSO, single-shot infusions of ibandronate (6 mg) were administered. Pain levels were documented 10 days before and after the infusion on a visual analogue scale (VAS). Patients were monitored regularly. RESULTS Of the 11 patients, 10 showed a distinct improvement in pain (based on VAS scores) within 48-72 h after infusion. The pain levels of the patients were significantly lower after ibandronate infusions (p < 0.01). The majority of patients were free or almost free of complaints over the following months. Four of the 11 patients returned for repeated infusions. At the time of writing, no severe side effects have been observed, and in particular there has been no case of medication-related jaw osteonecrosis. CONCLUSION We conclude that single-shot bisphosphonate infusions on demand are promising treatment alternatives in acute DSO. Single-shot bisphosphonate infusions of ibandronate were well tolerated and resulted in distinct, long lasting improvement in subjective pain levels based on VAS scores.

Antibiotic Concentrations in Saliva: A Systematic Review of the Literature, With Clinical Implications for the Treatment of Sialadenitis

PURPOSE The current recommendations for the treatment of bacterial salivary gland infections are mainly empirical. Therefore, an evidence-based literature review was conducted to identify antibiotics with favorable pharmacokinetics in saliva and to establish recommendations for the antibiotic treatment of sialadenitis. MATERIALS AND METHODS The authors performed a systematic review of the pertinent literature published from 1985 to 2013. If the predefined inclusion criteria were met, the articles were screened for various variables: antibiotic type, mode of administration, type of examined saliva, peak salivary antibiotic concentrations, biochemical methodology, and minimal inhibitory concentrations of bacteria implicated in sialadenitis (Staphylococcus aureus, Viridans streptococci, various gram-negative strains, and anaerobes). RESULTS The review included 18 studies. The systematic analysis of the reported results concurred that intravenously administered cephalosporins achieve the highest concentrations in saliva, followed by orally administered cephalosporins and fluoroquinolones. These concentrations exceed the minimal inhibitory concentrations of the bacteria of interest. Phenoxymethylpenicillin and tetracyclines are not secreted in the saliva at bactericidal levels. The antibiotic peak salivary levels depended on the type of saliva examined (parotid vs submandibular vs minor salivary gland) and the biochemical method of measurement (high-performance liquid chromatography vs bioassay). CONCLUSION Cephalosporins and fluoroquinolones display superior pharmacokinetics in saliva and cover the spectrum of all bacteria implicated in sialadenitis. Within the limitations of this review, they can be recommended for the treatment of bacterial salivary gland infections.

Conservative management of medication-related osteonecrosis of the maxilla with an obturator prosthesis

Advanced maxillary medication-related osteonecrosis of the jaw can cause extensive hard and soft tissue destruction that results in long-term oroantral fistulae. The surgical treatment of medication-related osteonecrosis of the jaw may relieve acute symptoms and eliminate the signs of inflammation, but the primary and sustained plastic closure of these defects can challenge both the clinician and the patients. Although the use of obturator prostheses for maxillary defects after ablative oncologic surgery is well documented, studies about this treatment for similar medication-related osteonecrosis of the jaw-related defects are missing. This presentation of clinical situations describes the use of obturators as a conservative alternative to repetitive surgery for the rehabilitation of selected maxillary defects with oroantral communications.