Sentinel lymph node biopsy in recurrent or secondary oral squamous cell carcinoma after previous neck dissection.

OBJECTIVES: The aim of this retrospective study was to evaluate the potential of sentinel lymph node biopsy (SLNB) in patients with recurrent or a secondary oral squamous cell carcinoma (OSCC) without clinical signs of lymph node metastases (cN0), who were previously treated with a surgical approach. PATIENTS AND METHODS: Retrospective analysis of all patients with cN0 recurrent or secondary OSCC, who were treated using SLNB after previous neck dissection. Endpoints were sentinel lymph node (SLN) detection rate, negative predictive value (NPV) and sensitivity. RESULTS: A total of 17 patients with a mean age of 68.6 years were included. SLN were detected in 15 of 17 cases (detection rate: 88.2%). In seven patients (41.2%), a bilateral or contralateral lymph drainage of a unilateral carcinoma was found. Two patients (11.8%) demonstrated a positive SLN upon pathohistological analysis, which led to an upstaging. In one case, a non-SLN was positive, which is considered a false-negative result. The mean follow-up for all patients with histologically negative SLN including the patients without a detected SLN was 11.8 months (range: 0-31 months). Of these, one patient developed (isolated) neck recurrence after 12 months resulting in an overall NPV of 86.7% and a sensitivity of 50.0% for the SLNB as a neck staging procedure. CONCLUSION: SLNB can improve the staging of patients with recurrent or secondary OSCC, who present with a history of a previous neck dissection. Further studies are required to demonstrate the oncological benefit of SLNB in this patient cohort.

A prospective, randomized, single-blind study to compare two methods of treating cystic lesions in the jaw.

OBJECTIVE: The study aimed to assess the usefulness of a bovine bone substitute material in treating cystic lesions in the jaw with a maximum diameter of <4 cm. MATERIAL AND METHODS: In this prospective, randomized, single-blind intervention study of 116 patients, 61 underwent cystectomy with a subsequent filling of the defect using a bovine xenograft, and 55 underwent cystectomy alone. Volumetric measurement of the cysts was performed preoperatively and 6 and 12 months postoperatively using the available digital volume tomography data sets. Follow-up appointments were made 14 days and 1, 3, 6, and 12 months postoperatively. RESULTS: Almost complete regeneration was seen in both treatment groups within 12 months, with no significant difference in absolute volume loss between the 2 groups (P = .521). Examination 14 days after surgery revealed a tendency for more wound healing disorders with the use of a bone substitute (P = .077). It was no longer possible to detect any further differences in later examinations. CONCLUSION: Using bovine bone substitute material has no radiologically measurable advantage over cystectomy alone without defect filling regarding bone regeneration. In addition, there was a tendency for more wound-healing disorders to occur in the bone substitute group.

Antibiotic resistance of the bacterial spectrum of deep space head and neck infections in oral and maxillofacial surgery - a retrospective study.

OBJECTIVES: The aim of this study was to evaluate the current resistance situation concerning routinely used antibiotics for treatment in odontogenic abscesses. MATERIALS AND METHODS: This retrospective study assessed patients with deep space head and neck infections who were treated by surgical intervention under general anesthesia at our department. The target parameter was the ascertainment of the resistance rates in order to identify the bacterial spectrum, sites in the body, length of inpatient stay, and the age and sex of the patients. RESULTS: A total of 539 patients, 268 (49.7%) males and 271 (50.3%) females were included in the study. The mean age was 36.5 ± 22.1 years. There was no significant difference between the two sexes with regard to the mean duration of hospitalization (p = 0.574). The predominant bacteria in the aerobic spectrum were streptococci of the viridans group and staphylococci, in the anaerobic spectrum Prevotella and Propionibacteria spp. Rates of resistance to clindamycin were between 34 and 47% in both the facultative and obligate anaerobic spectrum. Increased resistance was likewise found in the facultative anaerobic spectrum, with 94% resistance to ampicillin and 45% to erythromycin. CONCLUSION: Due to the increasing levels of resistance to clindamycin, their use in empiric antibiotic treatment for deep space head and neck infections should be viewed critically. CLINICAL RELEVANCE: Resistance rates continue to increase compared to previous studies. The use of these antibiotic groups in patients with a penicillin allergy needs to be called into question and alternative medications sought.

Pervasion of beta-tricalcium phosphate with nanodiamond particles yields efficient and safe bone replacement material amenable for biofunctionalization and application in large-size osseous defect healing.

Biofunctionalization of scaffold materials can enable the healing of large bone defects. In case of minimally invasive guided-bone regeneration (GBR), limitations are however hard-to-control side effects related to the potential release of biofactors into the systemic environment. Biofactors can be stably bound to nanodiamond particles (ND) through physisorption. We therefore tested the biological and clinical effects of refining beta-tricalcium phosphate (ßTCP) with ND in vitro and in vivo. In vitro, ßTCP carrying 4% ND resulted in enhanced attachment of mesenchymal stem cells. When assessing GBR after lateral augmentation of the mandible in sheep showed that ND in ßTCP resulted in a consistently steady bone formation when compared to pure ßTCP, demonstrating the biological inert behavior and the potential clinical safety of ND.