Christian Doll

Patient and treatment-related risk factors for osteoradionecrosis of the jaw in patients with head and neck cancer

OBJECTIVE The purpose of this study was to evaluate risk factors for and the incidence of osteoradionecrosis (ORN) of the jaw in patients with head and neck cancer. STUDY DESIGN This study was a retrospective analysis of the risk for ORN and outcome for 149 of 540 patients with head and neck cancer of the oral cavity (65%), oropharynx (26%), or other head and neck sites (9%) treated with radiotherapy between 2004 and 2009. ORN was graded according to Late Effects of Normal Tissues/Somatic Objective Management Analytic Scale (LENT/SOMA) criteria. RESULTS Within a median follow-up of 41 months (95% confidence interval: 27.4-54.6), 38 patients (25.5%) had developed ORN, 37 patients (25%) had a local recurrence, and 53 patients (36%) had died. The median time to diagnosis of ORN was 14.5 months (range: 3-80), and 79% were diagnosed within 2 years of RT. Eleven of these patients had undergone previous mandibular surgery. Univariate significant risk factors for ORN were any comorbidity, poor oral hygiene, pre-radiotherapy osteotomy, close tumor-to-bone proximity, post-radiotherapy dentoalveolar surgery (DAS), DAS without sufficient wound closure, alcohol consumption, and denture pressure sores. In multivariate analysis, comorbidities, pre-radiotherapy mandibular surgery, poor oral hygiene, and insufficient DAS remained significant. CONCLUSIONS Reducing the risk of ORN calls for maintaining optimal oral hygiene, ensuring good denture fit, receiving proper training in DAS, and helping patients to stop drinking and smoking.

Long-term peri-implant bone level changes of non-vascularized fibula bone grafted edentulous patients

Long-term results of reconstructions and prosthetic rehabilitation of patients presenting severely atrophied edentulous ridges remains a challenge for clinicians. Among the various available augmentation materials there is evidence that avascular fibula bone grafts possess a reliable resistance against resorption and may thus provide a valuable source to reduce the loss of vertical bone height after reconstruction of the severely atrophied mandible and maxilla. The purpose of the present study was to assess long-term crestal bone level stability in avascular fibula bone grafts. 8 edentulous female patients (average age 70.6 years) with Class-VI-atrophy and less than 5 mm residual bone volume received onlay-grafting with avascular fibula bone grafts and were monitored with a mean observation time of 133.7 months (121-186). A total of 39 implants were placed in the maxilla and mandible. Three patients received immediate and five patients delayed implant placement 3 months after grafting. All patients were provided with bar-retained dentures. Postoperative evaluation included clinical implant success (Buser) and radiographic examinations (orthopantomogram) to quantify crestal bone resorption. Grafting was successfully performed in all patients with no regrafting necessary. All implants but one, lost 2 years after abutment connection, remained successfully integrated and fulfilled the Buser criteria, rendering to a success rate of 97%. Mean bone resorption after 10 years was mesial 1.4 mm and distal 1.4 mm at each implant-site. Maximum bone resorption occurred between postoperative and first year, thereafter no significant resorption was measured in re-examinations up to 15 years. Avascular fibula grafts are a reliable bone graft for augmentation procedures in atrophied edentulous ridges. Dental implants that integrated in the autogenous fibular bone grafts showed a stable crestal peri-implant bone level up to 15 years after implant placement.

Drill‐related root injury caused by intraoperative intermaxillary fixation: an analysis of 1067 screw applications

BACKGROUND/AIMS Intermaxillary fixation is a standard procedure for the treatment of mandibular fractures or in orthognathic surgery. Predrilling for screws poses the risk of accidental tooth root injury, potentially leading to further pathological processes. Limited evidence about accidental tooth injury during intermaxillary fixation is available due to heterogenous study designs. The aim of this study was to evaluate the risk of root trauma using predrilled transgingival fixation screws and the clinical consequences for the affected teeth. MATERIALS AND METHODS In this retrospective study, the data of open reduction and internal fixation surgery files with intraoperative application of predrilled intermaxillary fixation screws were analysed. The postoperative radiographic images were evaluated for the occurrence of tooth root injury. Patients diagnosed with root injury were clinically followed up with respect to the dental health for the affected teeth. RESULTS A total of 133 radiologically diagnosed tooth root injuries were recorded (12.5% of screws). The median follow-up interval was 16 months (range: 3-77 months). The return rate was 49.5% for all patients. Of these, four of the injured teeth (3%) needed endodontic treatment. No toothache was reported, no tooth was lost, and no negative impact on periodontal health was clinically evident. CONCLUSION Intermaxillary fixation with predrilled transgingival screws is a safe way to manage mandibular fractures. The incidence of tooth root injury is not uncommon, but the adverse side effects are rare and the health of the affected teeth is mostly not compromised.

Retrospective long-term analysis of bone level changes after horizontal alveolar crest reconstruction with autologous bone grafts harvested from the posterior region of the mandible.

Purpose The goal of this study was to evaluate the long-term success of horizontal alveolar crest augmentation of the retromolar region of the mandible with particulated bone, as well as factors affecting subsequent peri-implant bone loss. Methods A total of 109 patients (68 female, 41 male) suffering from alveolar ridge deficiencies of the maxilla and mandible were included in this study. All patients were treated with particulated retromolar bone grafts from the mandible prior to the insertion of endosseous dental implants. Mesial and distal peri-implant crestal bone changes were assessed at six time points. Several parameters, including implant survival and the influence of age, gender, localisation of the implant, diameter, covering procedures, and time points of implant placement, were analysed to identify associations with bone level changes using the Mann-Whitney U-test, the Kruskal-Wallis test, and Spearmans rank-order correlation coefficient. Results A total of 164 dental implants were placed in the maxilla (n=97) and in the mandible (n=67). The mean observation period was 105.26±21.58 months after implantation. The overall survival rate was 97.6% after 10 years. Overall, peri-implant bone loss was highest during the first year, but decreased over time. The mean amount of bone loss after 10 years was 2.47 mm mesially and 2.50 mm distally. Bone loss was significantly influenced by implant type and primary stability. Conclusions The use of particulated autologous retromolar bone grafts is a reliable technique for the horizontal reconstruction of local alveolar ridge deficiencies. Our results demonstrate that implants placed in augmented bone demonstrated similar bone level changes compared to implants inserted in non-augmented regions.

Severe tooth loss after root damage caused by predrilled intermaxillary fixation screw: a case report

Intermaxillary fixation (IMF) with screws is routinely used as a conservative therapy or to obtain normal occlusion during the surgical procedure of open reduction and internal fixation for treating mandibular fractures. The risk of iatrogenic dental damage caused by interdental drilling is widely known. Several side effects are described, including loss of response to pulp sensibility testing, root fracture, and, loss of the tooth. This is a case report about a young man who had undergone temporary IMF treatment with a single proven root damage. The patient did not appear for follow-up but he presented 5 years afterward with local purulent osteomyelitis concerning the affected and the adjacent teeth. Osteotomy and extraction of two premolars and one molar were necessary for rehabilitation. This case report illustrates the importance of careful use of predrilled IMF screws and the necessity of frequent follow-ups in cases of proven tooth root damage due to IMF treatment.

Clinical characteristics and immunohistochemical analysis of p53, Ki-67 and cyclin D1 in 80 odontogenic keratocysts

OBJECTIVE The aim of this study was to evaluate clinical parameters and expression patterns of Ki-67, cyclin D1 and p53 in odontogenic keratocysts. MATERIAL AND METHODS In this study, fifty-three patients with 80 odontogenic keratocysts were included. The medical records of these patients were reviewed retrospectively. To elucidate the molecular pathogenesis of the disease, the expression of p53, Ki-67 and cyclin D1 was analyzed using immunohistochemistry. RESULTS A total of 53 patients (mean age 38 years) with a median follow-up of 4.2 years (ranging from 4 days to 14.4 years) were evaluated. The rates of recurrence and post-operative complications varied depending on the surgical approach: cystectomy and peripheral ostectomy led to manageable low rates of complications and recurrence frequency. Immunohistochemical evaluation revealed that all lesions were positive for Ki-67 and cyclin D1 expression. The expression of Ki-67 was associated with the degree of inflammation. Cyclin D1 was expressed significantly higher in syndrome-associated keratocystic lesions. In contrast to non-syndromal lesions, all syndromal lesions expressed p53. CONCLUSION This investigation demonstrates that the pathogenesis of syndromal keratocysts appears to differ from sporadic odontogenic keratocysts. Additionally, the primary and recurrent non-syndromal keratocysts have a similar etiology, as no differences in the expression patterns of Ki-67, p53 and cyclin D1 were observed.

Possible Estrogen Dependency in the Pathogenesis of Branchial Cleft Cysts

Background Even though branchial cleft cysts are currently accepted as a congenital anomaly, there is often a long delay until clinical presentation; branchial cleft cysts classically appear in the second to fourth decade of life. Our observation of their occurrence in three pregnant women encouraged us to contemplate a possible hormonal influence. Methods Immunohistological analysis was performed for the evaluation of the estrogen receptor alpha (ERα) in paraffin-embedded tissue specimens of 16 patients with a diagnosis of branchial cleft cyst, with three of them being pregnant. Results Expression of ERα was detected within epithelial cells only in branchial cleft cysts in pregnant females; moreover, higher growth fractions (Ki-67/Mib1) were found. Conclusion The fact that the estrogen receptor was expressed only in pregnant women, in contrast to 13 investigated cases, may suggest that the high level of estrogen in pregnancy is a possible explanation for the spontaneous growth of branchial cleft cysts.

The lower trapezius island myocutaneous flap in tunnelled technique to cover complicated tissue defects located between the craniocervical and cervicothoracic junction following spinal surgery

PURPOSE Stable coverage of complicated defects located between the craniocervical and cervicothoracic junction following wound healing disturbance after spinal surgery can be challenging. Especially in cases where devices are exposed, well-vascularized coverage is required to achieve stable wound conditions. Therefore, the aim of the present study was to evaluate the clinical outcome of the lower trapezius island myocutaneous flap (LTIMF) as a possible treatment option. MATERIALS AND METHODS Four patients with a mean age of 68.8 years (ranging from 50 to 93 years) with wound healing disturbance following spinal surgery leading to defects of the dorsal neck/upper back refractory to conservative treatment and surgical debridement were included. All defects were reconstructed with a LTIMF based on the transverse cervical artery. RESULTS Mean follow-up was 16.5 months (ranging from 5 to 30 months). No major flap failure occurred; minor complications in three patients including lateral superficial skin necrosis were easily handled. In all patients, excellent functional and aesthetic results were achieved. CONCLUSION The lower trapezius island myocutaneous flap represents a reliable treatment option to cover complicated defects located between the craniocervical and cervicothoracic junction following wound disturbance after spinal surgery.