Virtual planning for mandible resection and reconstruction.

In mandibular reconstruction, computer-assisted procedures, including virtual surgical planning (VSP) and additive manufacturing (AM), have become an integral part of routine clinical practice. Especially complex cases with extensive defects after ablative tumor surgery benefit from a computer-assisted approach. Various CAD/CAM-manufactured tools such as surgical guides (guides for osteotomy, resection and predrilling) support the transition from virtual planning to surgery.

MRI-detected intraosseous bone marrow edema recedes after effective therapy of periodontitis.

Objectives: T2 STIR MRI sequences can detect preclinical changes associated with periodontal inflammation, i.e. intraosseous edema in the tooth-supporting bone.

Nodal Disease and Survival in Oral Cancer: Is Occult Metastasis a Burden Factor Compared to Preoperatively Nodal Positive Neck?

The impact of neck involvement and occult metastasis (OM) in patients with oral squamous cell carcinoma (OSCC) favors an elective neck dissection. However, there are barely any existing data on survival for patients with OM compared with patients with positive lymph nodes detected preoperatively. This study aims to compare survival curves of patients suffering from lymph nodal metastases in a preoperatively N+ neck with those suffering from OM.

Digital planning and individual implants for secondary reconstruction of midfacial deformities: A pilot study.

Objective: To evaluate the feasibility and accuracy of implementing three-dimensional virtual surgical planning (VSP) and subsequent transfer by additive manufactured tools in the secondary reconstruction of residual post-traumatic deformities in the midface.

Methods: Patients after secondary reconstruction of post-traumatic midfacial deformities were included in this case series. The metrical deviation between the virtually planned and postoperative position of patient-specific implants (PSI) and bone segments was measured at corresponding reference points.

Cancer testis antigen (PRAME) as an independent marker for survival in oral squamous cell carcinoma (OSCC).

Background: The objective was to assess the expression patterns of the cancer testis antigen PRAME, NY-ESO1, and SSX2 in oral squamous cell carcinoma (OSSC) and to correlate the expression with clinical and histopathological parameters including progression-free survival analysis.

Methods: The study variables of this retrospective cohort study (n = 83) included demographic data, histopathological data, and information on progression-free survival. PRAME expression patterns were rated based on immunohistochemistry on tissue microarrays (TMA).

Accuracy of free-hand positioned patient specific implants (PSI) in primary reconstruction after inferior and/or medial orbital wall fractures.

Background: To assess the accuracy with which CAD/CAM-fabricated patient-specific titanium implants (PSI) are positioned for inferior and/or medial orbital wall reconstruction without the use of intraoperative navigation.

Methods: Patients who underwent a primary reconstruction of the orbital walls with PSI due to fractures were enrolled in this retrospective cohort analysis. The primary outcome variables were the mean surface distances (MSD) between virtually planned and postoperative PSI position and single linear deviations in the x-, y- and z-axis at corresponding reference points.

Geometric accuracy of magnetic resonance imaging-derived virtual 3-dimensional bone surface models of the mandible in comparison to computed tomography and cone beam computed tomography: A porcine cadaver study.

Background: Providing accurate 3-dimensional virtual bone surface models is a prerequisite for virtual surgical planning and additive manufacturing in craniomaxillofacial surgery. For this purpose, magnetic resonance imaging (MRI) may be a radiation-free alternative to computed tomography (CT) and cone beam computed tomography (CBCT).

Purpose: The aim of this study was to assess the geometric accuracy of 3-dimensional T1-weighted MRI-derived virtual bone surface models of the mandible in comparison to CT and CBCT.

Prediction of surface area size in orbital floor and medial orbital wall fractures based on topographical subregions.

Objective: This retrospective study evaluates the occurrence and frequency of different fracture patterns in a series of computed tomography (CT) scans in terms of the AOCMF Trauma Classification (TC) orbit module and correlates the assigned defects with measurements of the fracture area in order to get an approximate guideline for fracture size predictions on the basis of the classification.

Material And Methods: CT scans of patients with orbital floor fractures were evaluated using the AOCMFTC to determine the topographical subregions. The coding consisted of: W = orbital wall, 1 = anterior orbit, 2 = midorbit, i = inferior, m = medial.

Magnetic resonance imaging as a diagnostic tool for periodontal disease: A prospective study with correlation to standard clinical findings-Is there added value?

Aim: To evaluate the correlation between standard clinical findings, radiographic (OPT) and magnetic resonance imaging (MRI) as well as to assess whether MRI is capable of providing additional information related to the severity and extent of periodontal disease.

Methods: 42 patients with generalized periodontitis received pre-interventional MRI scans. These were compared to MR images of a periodontal healthy control group (n = 34).

Magnetic resonance imaging based computer-guided dental implant surgery-A clinical pilot study.

Background: Computer-guided implant surgery is currently based on radiographic techniques exposing patients to ionizing radiation.

Purpose: To assess, whether computer-assisted 3D implant planning with template-guided placement of dental implants based on magnetic resonance imaging (MRI) is feasible.

Materials And Methods: 3-Tesla MRI was performed in 12 subjects as a basis for prosthetically driven virtual planning and subsequent guided implant surgery.

Bone regeneration of minipig mandibular defect by adipose derived mesenchymal stem cells seeded tri-calcium phosphate- poly(D,L-lactide-co-glycolide) scaffolds.

Reconstruction of bone defects represents a serious issue for orthopaedic and maxillofacial surgeons, especially in extensive bone loss. Adipose-derived mesenchymal stem cells (ADSCs) with tri-calcium phosphates (TCP) are widely used for bone regeneration facilitating the formation of bone extracellular matrix to promote reparative osteogenesis. The present study assessed the potential of cell-scaffold constructs for the regeneration of extensive mandibular bone defects in a minipig model.

Clinical analysis of MatrixMANDIBLE Preformed Reconstruction Plate design.

MatrixMANDIBLE Preformed Reconstruction Plates (MMPRPs) were developed to overcome laborious bending procedures of conventional reconstruction plates. The design comprises three sizes with a nonbendable centerpiece and two bendable sections (proximal and distal). According to the surgical protocol unnecessary parts are trimmed after the last used screw hole.

Mechanical and biological effects of infiltration with biopolymers on 3D printed tricalciumphosphate scaffolds.

The aim of this study was to evaluate the influence of infiltrating 3D printed (TCP) scaffolds with different biodegradable polymers on their mechanical and biological properties. 3D printed TCP scaffolds with interconnecting channels measuring 450±50 µm were infiltrated with four different biodegradable copolymers. To determine the average compressive strength, a uniaxial testing system was used.

Comorbidity Assessment in Patients With Oral Squamous Cell Carcinoma: Can Imaging Techniques (Fludeoxyglucose Positron-Emission Tomographic Computed Tomography and Contrast-Enhanced Computed tomography) Provide Additional Information?

Purpose: This study evaluated the role of imaging staging examinations (positron-emission tomographic computed tomography [PET/CT] and contrast-enhanced computed tomography [ceCT]) for the assessment of the comorbidity status of patients with oral squamous cell carcinoma (OSCC). A binary null hypothesis was drafted: 1) imaging staging examinations do not augment knowledge about the comorbidity status of patients with OSCC and 2) there is no difference between PET/CT and ceCT in this regard.

Materials And Methods: A retrospective cohort study design was selected to address the research question.

Magnetic resonance imaging of the inferior alveolar nerve with special regard to metal artifact reduction.

Purpose: Magnetic resonance imaging (MRI) is an excellent imaging modality for displaying peripheral nerves. Since the knowledge about MRI of the inferior alveolar nerve (IAN) is limited, this pilot study aims to identify the prospects and limitations of MRI of the IAN, with special consideration of metal artifacts.

Materials And Methods: Initially, in vitro MRI of a dental implant was performed to establish an optimized protocol for metal artifact reduction using WARP sequences (a software package provided by Siemens Healthcare, Erlangen, Germany) including view angle tilting (VAT) and slice-encoding metal artifact correction (SEMAC) techniques.

Comparative 3D micro-CT and 2D histomorphometry analysis of dental implant osseointegration in the maxilla of minipigs.

Aim: The bone implant contact (BIC) has traditionally been evaluated with histological methods. Thereupon, strong correlations of two-dimensional (2D) BIC have been detected between μCT and destructive histology. However, due to the high intra-sample variability in BIC values, one histological slice is not sufficient to represent 3D BIC.

Micro-CT vs. Whole Body Multirow Detector CT for Analysing Bone Regeneration in an Animal Model.

Objectives: Compared with multirow detector CT (MDCT), specimen (ex vivo) micro-CT (μCT) has a significantly higher (~ 30 x) spatial resolution and is considered the gold standard for assessing bone above the cellular level. However, it is expensive and time-consuming, and when applied in vivo, the radiation dose accumulates considerably. The aim of this study was to examine whether the lower resolution of the widely used MDCT is sufficient to qualitatively and quantitatively evaluate bone regeneration in rats.

Computer-Assisted Designed and Manufactured Procedures Facilitate the Lingual Application of Mandible Reconstruction Plates.

Purpose: Lingual positioning of mandible reconstruction plates can prevent typical complications such as plate exposure and orocutaneous fistulas. The aim of this study was to evaluate the feasibility and clinical outcomes of lingually applied patient-specific reconstruction plates.

Materials And Methods: A retrospective cohort study of patients managed with reconstruction plates positioned at the lingual side of the mandible was performed.

Iterations of computer- and template assisted mandibular or maxillary reconstruction with free flaps containing the lateral scapular border--Evolution of a biplanar plug-on cutting guide.

Background: Computer-assisted planning and intraoperative implementation using templates have become appreciated modalities in craniofacial reconstruction with fibula and DCIA flaps due to saving in operation time, improved accuracy of osteotomies and easy insetting. Up to now, a similar development for flaps from the subscapular vascular system, namely the lateral scapular border and tip, has not been addressed in the literature.

Patients/method: A cohort of 12 patients who underwent mandibular (n = 10) or maxillary (n = 2) reconstruction with free flaps containing the lateral scapular border and tip using computer-assisted planning, stereolithography (STL) models and selective laser sintered (SLS) templates for bone contouring and sub-segmentation osteotomies was reviewed focussing on iterations in the design of computer generated tools and templates.

Are There Clinical or Pathological Parameters of Maxillary Oral Squamous Cell Carcinoma With an Influence on the Occurrence of Neck Node Metastasis? An Appraisal of 92 Patients.

Purpose: To determine the proportion of patients with cervical metastases caused by maxillary oral squamous cell carcinoma (OSCC) and to identify any clinical or pathologic parameters that might be associated with the occurrence of metastatic neck disease.

Materials And Methods: A retrospective cohort study of all patients managed with primary surgical resection of maxillary OSCC at the authors' institution from 2006 through 2013 was performed. Cervical lymph node dissection and adjuvant therapy were performed as warranted by preoperative staging examinations or histopathologic evaluation or as recommended after multidisciplinary consultation, and regular follow-up protocols were followed.

Vascular endothelial growth factor receptor isoforms: are they present in oral squamous cell carcinoma?

Purpose: Although the clinical importance of vascular endothelial growth factor (VEGF) overexpression in oral squamous cell carcinoma (OSCC) has been investigated, there are limited data about the overexpression of VEGF receptors (VEGF-Rs) and their clinical importance. VEGF-R isoforms have proven influence on proliferation rates, metastasis, and survival in different neoplasms. This study was conducted to investigate VEGF-R expression levels in OSCC samples and to identify any clinical relevance.

Imaging characteristics of a Stafne bone cavity--panoramic radiography, computed tomography and magnetic resonance imaging.

Introduction: A rare case of Stafne bone cavity (SBC) with salivary gland herniation confirmed by magnetic resonance imaging (MRI) is described.

Results: It was diagnosed in a 72-year-old male patient. Surgical intervention was avoided.

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.

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.