Autologous versus prosthetic nasal and auricular reconstruction - patient, professional and layperson perceptions.

The aim of this study was to retrospectively evaluate the perceptions of aesthetic outcome following the autologous and prosthetic reconstruction of nasal and auricular defects among patients, professionals (oral and maxillofacial surgeons and ear, nose and throat surgeons) and people unfamiliar with reconstructive surgery. The influence of anatomical subunits on the overall perception of nasal and auricular reconstructions was also determined. A total of 119 patients treated for nasal and auricular defects between 1997 and 2016, with a minimum follow-up period of 6 months, were selected, and photographs of 77 of these patients (65%) were presented in a digital survey and reviewed using a standardized questionnaire. No clinically relevant correlations were found between the age or gender of patients (as well as those of the respondents) and their scores. Prosthetic reconstructions of nasal and auricular defects were considered advantageous over autologous reconstructions in terms of the subjective aesthetic outcome in the view of the professionals, in particular oral and maxillofacial surgeons; however, the patients judged both techniques to be equally effective in terms of aesthetics. No anatomical subunits were found to have a significant impact on the overall match of a nasal or auricular reconstruction with the patient's face.

Reliability and accuracy of cone beam computed tomography versus conventional multidetector computed tomography for image-guided craniofacial implant planning: An in vitro study.

PURPOSE: To assess the reliability and accuracy of linear measurements on three-dimensional (3D) cross-sectional images, both acquired with cone beam computed tomography (CBCT) and multi-detector row CT (MDCT). Bone thickness was evaluated with regard to image-guided planning of craniofacial implant surgery. MATERIALS AND METHODS: Five dry human skulls were used. Cuts were made with a circular bone saw at the ideal implant positions in the nasal, orbital, and temporal regions prior to acquisition of CBCT and MDCT scans. After imaging examination, bone width was assessed by three independent observers using a caliper and defined as a reference. In the next step, cross-sectional images of the regions with the aforementioned cuts were reconstructed from 3D virtual models generated from the digital DICOM datasets with the use of 3D image-based planning software. Subsequently, linear measurements were performed. The systematic difference and interobserver and intraobserver variation of MDCT and CBCT linear measurements were compared with the physical measurements at different locations in the nasal, orbital, and temporal region, respectively. Also, the potential influence of different gray-level values was investigated. The quantitative accuracy of distance measurements was performed using a two-way analysis of variance (ANOVA) and variance component analyses. Only differences with P values < .05 were considered significant. RESULTS: All radiologic measurements showed a significant overestimation of the bony dimensions, reaching more than the used voxel sizes of 0.3 mm for CBCT and 0.5 mm for MDCT. For CBCT, an average measurement bias of 0.39 to 0.53 mm and for MDCT of 0.57 to 0.59 mm was found. MDCT images showed less interobserver variation in linear measurements on cross-sectional images from 3D virtual models compared with CBCT images. Contrast settings statistically significantly influenced linear measurements of bone width for CBCT images (P < .0015) and interobserver variation on MDCT imaging (P < .029). CONCLUSION: Both CBCT images (KaVo 3D eXam Imaging System) and MDCT images (Aquilion ONE, Toshiba) showed a highly consistent submillimeter overestimation of the anatomical truth in assessing bone thickness of nasal, orbital, and temporal regions of ex vivo specimens. When using CBCT and MDCT images for presurgical assessment, one should be aware of the overestimation of the cortical bone thickness.

Reliability and accuracy of skin-supported surgical templates for computer-planned craniofacial implant placement, a comparison between surgical templates: With and without bony fixation.

INTRODUCTION: The purpose is to determine the accuracy of guided implant placement in the orbital, nasal, and auricular region using computer-aided designed stereolithographic skin-supported surgical templates with and without bone fixation pins. MATERIALS AND METHODS: Preoperatively, cone-beam CT (CBCT) and multiple detector computed tomography (MDCT) scans were acquired from 10 cadaver heads, followed by virtual planning of implants in the orbital margin, auricular region and nasal floor. Surgical skin-supported templates were digitally designed to allow flapless implant placement. Fixation pins were used for stabilization comprising half of all templates in predetermined bone areas. The accuracy of the surgical templates was validated by comparing the achieved implant location to its virtual planned implant position by calculating the linear and angular deviations. RESULTS: Surgical templates with the use of bone fixation pins produced statistically significant greater implant deviations as compared to the non-fixated surgical templates. CONCLUSION: The results of this study indicate that significant deviation has to be taken into account when placing cranio-maxillofacial implants using skin-supported surgical templates. Surprisingly, the use of bone-fixated pins worsened the accuracy.

Clinical relevance of cone beam computed tomography in mandibular third molar removal: A multicentre, randomised, controlled trial.

PURPOSE: The aims of this study were to investigate the effectiveness of cone beam computed tomography (CBCT) compared to panoramic radiography (PR), prior to mandibular third molar removal, in reducing patient morbidity, and to identify risk factors associated with inferior alveolar nerve (IAN) injury. MATERIAL AND METHODS: This multicentre, randomised, controlled trial was performed at three centres in the Netherlands. Adults with an increased risk for IAN injury, as diagnosed from PR, were included in the study. In one arm of the study, patients underwent an additional CBCT prior to third molar surgery. In a second arm of the study, no additional radiographs were acquired. The primary outcome measure was the number of patient-reported altered sensations 1 week after surgery. As secondary outcome measures, the number of patients with objective IAN injury, with long-term (>6 months) IAN injury, the occurrence of other postoperative complications, the Oral Health Related Quality of Life-14 (OHIP-14) questionnaire responses, postoperative pain (visual analogue scale score), duration of surgery, number of emergency visits, and number of missed days of work or study were scored. RESULTS: A total of 268 patients with 320 mandibular third molars were analysed according to the intention-to-treat principle. The overall incidence of IAN injury 1 week after surgery was 6.3%. No significant differences between CBCT and PR for temporary IAN injury (p = 0.64) and all other secondary outcomes were registered. A lingual position of the mandibular canal (MC) and narrowing, in which the diameter of the MC lumen was decreased at the contact area between the MC and the roots, were significant risk factors for temporary IAN injury. CONCLUSION: Although CBCT is a valuable diagnostic adjunct for identification of an increased risk for IAN injury, the use of CBCT does not translate into a reduction of IAN injury and other postoperative complications, after removal of the complete mandibular third molar. In these selected cases of a high risk for IAN injury, an alternative strategy, such as monitoring or a coronectomy, might be more appropriate. (http://clinicaltrials.gov, NCT02071030).

[A diagnosed follicular cyst turned out to be a squamous cell carcinoma]. / Een gediagnosticeerde folliculaire cyste bleek een plaveiselcelcarcinoom.

A 50-year-old man had undergone a complicated removal of tooth 48 which initially seemed related to a follicular cyst. Subsequently, it turned out that a squamous cell carcinoma had probably developed from the follicular cyst. The patient underwent excision of the tumour, hemimandibulectomy, a neck dissection, and reconstruction of the mandibula using a metal plate, followed by postoperative local radiotherapy. This type of development of a squamous cell carcinoma presents very rarely. From the literature, it can be concluded that the prognosis is unfavourable and that the tumour tends to grow aggressively. In case of abnormal wound healing after the removal of a tooth (with a follicular cyst), it is recommended to examine representative tissue histologically.

Interforaminal implant placement in oral cancer patients: during ablative surgery or delayed? A 5-year retrospective study.

In a retrospective study, two mandibular prosthetic rehabilitation strategies supported by implants in oral cancer patients were evaluated: implants placed in the non-resected edentulous symphyseal area during ablative surgery (DAS implants); or at a later stage (postponed (P) implants). Medical files of patients from two head-neck oncology groups from 2000 to 2005 were screened for study inclusion. DAS protocol was used in one group and P protocol in the other. After a 5 year follow-up of 261 edentulous patients with oral cancer in the second group, P implants were placed in 27 patients to support an overdenture. Of the 249 edentulous patients in the first group, 82 patients were given an implant supported overdenture using the DAS implant protocol. Regarding implant loss, no statistically significant differences were seen between the DAS and P implants. In the DAS group, more patients benefited from an implant-supported lower overdenture (39 versus 11%, respectively), and they received their overdenture on average 20.0 months sooner (sd=11.01, p<0.001) after ablative surgery. 17.1% of DAS implants and 4.6% of P implants were never loaded due to tumour and patient related factors including unfavourable implant soft tissue, tumour recurrence near the implant, or radiotherapy induced trismus.

Extra-oral implants: insertion per- or post-ablation?

Although the benefit of extra-oral implants in the reconstruction of maxillofacial oncological defects is undisputable, some relevant issues need to be clarified. The purpose of this retrospective study was to evaluate the relationship between implants placed during ablation (DA-implants) and after ablation (AA-implants) of the tumor with respect to implant survival. In total, 103 implants were assessed: 44 nasal implants (17 patients) and 59 orbital implants (18 patients). All patients received their implant-retained maxillofacial epithesis between 1997 and 2010, with a mean follow-up of 35 months (range 8-156 months). The survival rate of DA-implants was 90.0% for the orbital region and 93.5% for the nasal region. The survival rate of the AA-implants for the orbital and the nasal region was 82.8% and 61.5%, respectively. This study shows a significant higher survival rate of extra-oral implants placed during ablative surgery compared to implants in a later stage (p=0.044), thereby stressing the importance of installing extra-oral implants during the ablative surgical session.

[Face the facial furuncle]. / De furunkel in het (ge) zicht.

The furuncle is a staphylococcal infection of a single hair follicle which can occur on the skin in the maxillofacial region. Untreated, this infection can lead to life-threatening situations. This article discusses the etiology, clinical findings, possible complications as well as a series of differential diagnoses. In addition, several therapeutic and preventive strategies are described.