Comparison of the Accuracy and Clinical Parameters of Patient-Specific and Conventionally Bended Plates for Mandibular Reconstruction.

OBJECTIVES: This retrospective study compared two mandibular reconstruction procedures-conventional reconstruction plates (CR) and patient-specific implants (PSI)-and evaluated their accuracy of reconstruction and clinical outcome. METHODS: Overall, 94 patients had undergone mandibular reconstruction with CR (n = 48) and PSI (n = 46). Six detectable and replicable anatomical reference points, identified via computer tomography, were used for defining the mandibular dimensions. The accuracy of reconstruction was assessed using pre- and postoperative differences. RESULTS: In the CR group, the largest difference was at the lateral point of the condyle mandibulae (D2) -1.56 mm (SD = 3.8). In the PSI group, the largest difference between preoperative and postoperative measurement was shown at the processus coronoid (D5) with +1.86 mm (SD = 6.0). Significant differences within the groups in pre- and postoperative measurements were identified at the gonion (D6) [t(56) = -2.217; p = .031 <.05]. In the CR group, the difference was 1.5 (SD = 3.9) and in the PSI group -1.04 (SD = 4.9). CR did not demonstrate a higher risk of plate fractures and post-operative complications compared to PSI. CONCLUSION: For reconstructing mandibular defects, CR and PSI are eligible. In each case, the advantages and disadvantages of these approaches must be assessed. The functional and esthetic outcome of mandibular reconstruction significantly improves with the experience of the surgeon in conducting microvascular grafts and familiarity with computer-assisted surgery. Interoperator variability can be reduced, and training of younger surgeons involved in planning can be reaching better outcomes in the future.

Use and Evaluation of a Computer-Assisted Examination Method for the Diagnosis and Analysis of Medication-Related Osteonecrosis of the Jaw.

The aim of the present study was to analyze the size of the preoperatively calculated defect volume of MRONJ patients (medication-related osteonecrosis of the jaw) and to develop a computer-aided tool based on techniques of AI (artificial intelligence) that facilitates diagnostics of MRONJ. For this purpose, on the basis of 3D (three-dimensional) data sets of 175 MRONJ patients, the outline of the necrosis was marked with the software iPlan 3.0.5 (BrainLAB AG) thus determining the respective volume. The correlation of this volume with other 31 collected parameters was analyzed retrospectively. There was a significant correlation between the defect volume on the one hand, and the MRONJ stage, the number of performed operations, and the therapy invasiveness on the other hand. Furthermore, it could be shown that in one third of the cases no defects could be recognized in the 2D imaging by panoramic radiograph, while in the 3D data sets defects already had been demarcated. On the basis of these data, a computer-aided tool based on the principles of AI was developed and validated, which might allow the automated calculation of the 3D defect extension and classification of the MRONJ cases into a ranking system. In conclusion, preparation of a 3D image can be recommended for reliably making the diagnosis "MRONJ." Moreover, knowledge of the exact defect volume serves as a decision-making aid with regard to the choice of therapy, ensures intraoperative certitude, and allows an assessment of the prognosis.

Removal of stones from the superficial lobe of the submandibular gland (SMG) via an intraoral endoscopy-assisted sialolithotomy.

OBJECTIVES: Sialolithiasis is the most common cause of chronic sialadenitis of the submandibular gland (SMG). Symptomatic superficial lobe stones are often treated by submandibulectomy. A gland preserving operation allows for transoral stone removal through endoscopically assisted sialolithotomy. Herein, we provide clinical and sonographical follow-up data in patients who underwent sialolithotomy under general anesthesia. MATERIALS AND METHODS: Sixty patients treated at the Department of Oral and Maxillofacial Surgery at Düsseldorf University Hospital for superficial lobe sialolithiasis of SMG were included in this study. All received transoral sialolithotomy under general anesthesia. Follow-up was conducted via standardized patient questionnaires, clinical examination, and B-mode and color Doppler sonography. RESULTS: Mean patient age was 48.9 years. 56.6% of right and 43.4% of left SMG were affected. Mean follow-up was 45 months. Fifty-five of 59 detected stones could be removed. Mean operation time was 71 min. 3.3% of patients reported recurrent episodes of postoperative pain and 10% felt recurrent episodes of gland swelling. Persistent postoperative lingual nerve hypesthesia was described in one patient. No facial nerve damages occurred. Salivary flow rates remained reduced in most of the affected glands upon stone removal. Sonographical follow-up data of the previously affected SMG after intraoral endoscopy-assisted sialolithotomy showed a regular gland size in 70.8% of cases, a parenchyma free of inflammation in 93.8%, and without signs of fibrosis in 72.9% of cases. 68.7% of patients showed a regular structure of Wharton's duct at time of follow-up. In total, 89.6% of patients were diagnosed stone-free within both glands on follow-up. No case required subsequent submandibulectomy. CONCLUSIONS: Sialolithotomy of Wharton's duct for removal of stones from the SMG's superficial lobe is a promising alternative to submandibulectomy. CLINICAL RELEVANCE: Reduction of postoperative morbidity through endoscopically assisted sialolithotomy for removal of superficial lobe stones from SMG. TRIAL REGISTRATION: Ethics Committee of Heinrich-Heine-University Düsseldorf (no. 5586).

Histopathological and patient-related characteristics of basal cell carcinomas of the head and neck influencing therapeutic management.

The authors hypothesize that histopathological characteristics of basal cell carcinomas of the head and neck (BCCHN) have changed over time and the correlation of BCCHN localization and histological tumour type can help improving the number and quality of necessary therapeutic interventions. Information of 222 patients with 344 BCCHN was gained. Descriptive measures were compared to prior studies to prove whether or not characteristics of basal cell carcinomas or patients have changed over time. Afterwards descriptive measures were correlated with number of conducted operations to evaluate if tumour localization, histological tumour type and number of operations depend on one another. Aggravating factors which lead to a higher number of operations were older age, greater size of BCCHN, adjacent elastosis, the localizations eye, ear and nose and histological tumour types morpheaform and nodularulcerated. In comparison to earlier studies characteristics of BCCHN and patients showed positive developments because of grown awareness of BCCHN. Furthermore, our correlations demonstrate that therapeutic results of BCCHN treatment are continuously improving. Nevertheless, treatment of aggressive morpheaform BCCHN in combination with distinctive patient characteristics still needs improvement.

Cylindroma of head and neck: review of the literature and report of two rare cases.

Cylindromas are very rare and benign adnexal tumours of the skin. Very few reports of these benign tumours are reported in the literature. Dermal cylindromas are characterised as a benign neoplasm of the eccrine sweat glands. The most frequent location is the head and neck. Multiple occurrences are often linked to the Brooke-Spiegler syndrome. The Brooke-Spiegler syndrome is inherited as an irregular autosomal dominant trait. A malignant transformation to an adenoid cystic carcinoma is also described in the literature. The leading treatment modality described in the literature is the complete surgical removal of the lesions. Here, a systematic review of the literature is presented with two rare cases of cylindromas.

Bilateral multifocal Warthin's tumors in upper neck lymph nodes. Report of a case and brief review of the literature.

Cystadenolymphomas (Warthin's tumors) are the second most frequent lesions of the parotid gland. Due to their benign clinical behavior, the low rates of recurrence and malignant transformation they were classified as tumor-like lesions. In addition, a polyclonal growth of the epithelial components of the tumor could be detected. Warthin's tumors occur bilateral in 7-10%, whereas a multifocal appearance is extremely rare. Even if the pathogenesis is still unclear a heterotopia of salivary tissue during embryogenesis is the most likely explanation for the origin of these tumors in the upper neck and periparotideal region. Here we present a rare case of bilateral, multifocal, extraglandular Warthin's tumors in lymph nodes of the upper neck and give a brief review of the literature. If a primary malignancy can be excluded by a careful staging procedure prior to the operation an isolated excision of the lesions of the neck is the adequate treatment.