Ossifying fibroma of the skull: interactive image-guided minimally invasive localization and resection

Ossifying fibroma is a benign fibro-osseous tumor commonly affecting the craniofacial bones. It is considered to be a locally aggressive and quickly expansible bone lesion. Because of its aggressive nature and high recurrence rate, early detection and complete surgical removal are essential. Usually, these lesions are excised extensively by craniectomy, and bone loss is reconstructed by cranioplasty using acrylic resin or titanium implants. Alternatively, in the management of skull-ossifying fibroma, an image-guided technique using surgical navigation may provide precise information about localization, enabling complete removal, thereby operating with minimal exposure and within narrow resection borders and avoiding significant bone deformity. A 39-year-old male patient with a history of renal cell carcinoma was admitted to our hospital because a radionuclide scintigraphic bone scan revealed increased uptake in a small area located at the left lateral skull bone. The high-resolution computed tomography scan showed that the lesion was located inside the diploe, destroying the inner table of the calvarium. The patient underwent minimally invasive bone lesion removal using an interactive image-guided approach. Complete resection of the neoplastic lesion was achieved. The histopathological examination revealed an ossifying fibroma. The postoperative course was uneventful, and the patient was discharged 3 days after intervention. To date, there has been no evidence of local recurrence. Interactive multimodal planning and intraoperative image guidance offer an interesting approach for biopsy and minimally invasive removal of small ossifying fibroma lesions of the skull, especially in less accessible locations.     

Computer-aided dental implant planning

Computer-aided dental implant planning increases the predictability of replacing missing teeth in partially and fully edentulous cases. This article describes how Nobel Biocare's Procera surgical planning software converts a patient's double CT scan data into a virtual three-dimensional model of the alveolar bone and overlying prosthesis. Using these images, the practitioner virtually places implants in the bone in precise relation to their position in the final prosthesis. Procera uses this virtual plan to fabricate a customized surgical template that guides the placement of the implants safely, precisely, and accurately. Then the dental laboratory can construct the master cast and provisional restoration before surgery, allowing the restoration to be inserted immediately after placement of the implants. Furthermore, computer-based guided implant surgery is minimally invasive and requires a shorter chair time and fewer appointments than traditional methods.     

Minimal invasive biopsy of intraconal expansion by PET/CT/MRI image-guided navigation: A new method

Intraorbital tumours are often undetected for a long period and may lead to compression of the optic nerve and loss of vision. Although CT, MRI's and ultrasound can help in determining the probable diagnosis, most orbital tumours are only diagnosed by surgical biopsy. In intraconal lesions this may prove especially difficult as the expansions are situated next to sensitive anatomical structures (eye bulb, optic nerve). In search of a minimally invasive access to the intraconal region, we describe a method of a three-dimensional, image-guided biopsy of orbital tumours using a combined technique of hardware fusion between ¹⁸F-FDG Positron Emission Tomography (¹⁸F-FDG PET), magnetic resonance imaging (MRI) and Computed Tomography (CT).Method and materialWe present 6 patients with a total of 7 intraorbital lesions, all of them suffering from diplopia and/or exophthalmos. There were 3 female and 3 male patients. The patients age ranged from 20 to 75 years. One of the patients showed beginning loss of vision. Another of the patients had lesions in both orbits. The decision to obtain image-guided needle biopsies for treatment planning was discussed and decided at an interdisciplinary board comprising other sub-specialities (ophthalmology, neurosurgery, maxillofacial surgery, ENT, plastic surgery). All patients underwent 3D imaging preoperatively (¹⁸F-FDG PET/CT or ¹⁸F-FDG PET/CT plus MRI). Data was transferred to 3D navigation system. Access to the lesions was planned preoperatively on a workstation monitor. Biopsy-needles were then calibrated intraoperatively and all patients underwent three-dimensional image-guided needle biopsies under general anaesthesia.Results7 biopsies were performed. The histologic subtype was idiopathic orbital inflammation in 2 lesions, lymphoma in 2, Merkel cell carcinoma in 1, hamartoma in 1 and 1 malignant melanoma. The different pathologies were subsequently treated in consideration of the actual state of the art. In cases where surgical removal of the lesion was performed the histological diagnosis was confirmed in all cases.ConclusionThere is a wide range of possible treatment modalities for orbital tumours depending on the nature of the lesion. Histological diagnosis is mandatory to select the proper management and operation. The presented method allows minimal-invasive biopsy even in deep intraconal lesions, enabling the surgeon to spare critical anatomical structures. Vascular lesions such as cavernous haemangioma, tumour of the lacrimal gland or dermoid cysts present a contraindication and have to be excluded.     

Accuracy of guided biopsy of the jawbone in a clinical setting: A retrospective analysis

The aim of this study was to investigate the accuracy of a previously described technique for guided biopsy of osseous pathologies of the jawbone in a clinical setting. The data sets of patients who had undergone guided biopsy procedures were retrospectively examined for accuracy. Digital planning of the biopsies and manufacturing of the tooth-supported drilling template were performed with superimposed cone beam computed tomography and intraoral scans using implant planning software. After a trephine biopsy was taken using the template, the postoperative low-dose cone beam computed tomography was analyzed for accuracy using the planning software with the corresponding (digitally-planned) biopsy cylinder. The mean angular deviation was 4.35 ± 2.5°. The mean depth deviation was ?1.40 ± 1.41 mm. Guided biopsy seems to be an alternative to a conventional approach for minimally invasive and highly accurate jawbone biopsy.     

应用数字化流体树脂注射导板快速关闭正畸后前牙间隙1例

前牙间隙或缺损是临床修复治疗中的常见问题，针对患牙的不同情况经过数字微笑设计、蜡型等预告技术确认后，常采用贴面、全冠等修复方式来关闭间隙，而传统树脂直接修复技术关闭间隙是目前比较微创的修复方案，但费时费力，外形控制更加依赖经验。运用数字化技术可以更加精确快速地进行美学修复空间的设计、转移，使便捷地关闭前牙间隙及修复缺损成为可能。该技术流程按照实操次序，先后整合了虚拟设计与实体蜡型、实体导板转移设计轮廓形态、就位导板后通过预设通道注射树脂等核心步骤，简化医生的临床操作步骤与时间，与传统手工涂塑技术相比有效地提高了修复效果的可预测性和精确度，降低了技术敏感性，节约椅旁操作时间，为快速关闭前牙间隙及修复缺损提供了新的技术方案。     

Maxillo Mandibular Fixation in Edentulous Scenarios: Combined MMF Screws and Gunning Splints

A fracture of the maxillary or mandibular bone requires the afflicted to undergo a maxillo mandibular fixation for the establishment of pre traumatic occlusion. This process is quiet tedious and consumes a considerable period of time before any surgical procedure can commence. Such a situation can be complicated in case the individual with maxillomandibular fracture has sparse or absent dentition; for such cases a splint is fabricated or an erstwhile existing denture is used for maintaining a vertical jaw proportion. Stabilizing such splints to the jaw requires various invasive approaches that can bring into harm’s way, adjacent soft tissue vital structures. We describe here an innovative technique combining the time tested method of the “gunning splint” and the advanced minimally invasive MMF screws for obtaining closed reduction in edentulous jaw fractures.     

Surgical navigation for implant placement using transtomography

Objectives: To present a new guidance technique using transtomography in the operating room and to test the accuracy of this surgical protocol.
Material: A new concept of operating room, integrating when necessary this imagery to secure flapless procedures by intraoperative control, is described. This operating room concept, including X ray protection of the operators, is explained in addition to the transport system of the panoramic machine for its transfer to the patient who remains seated on his surgical chair.
Methods: Twenty-five single-tooth edentulous patients were treated by implant placement with a flapless or a minimally invasive procedure using transtomographic navigation. The surgical protocol is explained: after the first limited drill through mucosa and bone, intraoperative transtomography is performed with a custom-made titanium guide inserted into the bone. Images show the drilling axis in three dimensions. This form of navigation allows rectifying the drill axis. We explain how this protocol respects asepsis.
Results: The mean angular deviation was 2.04° in the mesiodistal direction (range: 0°–4.8°, variance: 2.88) and 2.71° in the buccal or the palatolingual direction (range: 0°–5.4°; variance: 2.63). Implant tip deviation was calculated: the mean mesiodistal tip deviation was 0.42 mm, and the mean buccal or palatolingual tip deviation was 0.5 mm. The maximum tip mesiodistal deviation was 1.08 mm and the maximum vestibular or palatolingual tip deviation was 1.22 mm.
Conclusion: This protocol appears to be as accurate as other guided or navigation systems. The advantages and limitations of this technique are explained, followed by future prospects with the new 3D cone beam computed tomography developed with the same panoramic machine.     

Accelerated orthodontic treatment with piezocision: a mini-invasive alternative to conventional corticotomies

An increasing number of adult patients are seeking orthodontic treatment and a short treatment time has become a recurring request. To meet their expectations, a number of surgical techniques have been developed to accelerate orthodontic tooth movement. However, these have been found to be quite invasive. We are introducing here a new, minimally invasive flapless procedure, combining micro incisions, piezoelectric incisions and selective tunneling that allows for hard- or soft-tissue grafting. Combined with a proper treatment planning and a good understanding of the biological events involved, this novel technique can locally manipulate alveolar bone metabolism in order to obtain rapid and stable orthodontic results. Piezocision allows for rapid correction of severe malocclusions without the drawbacks of traumatic conventional corticotomy procedures.     

Flapless approach to maxillary sinus augmentation using minimally invasive antral membrane balloon elevation

In the atrophic posterior maxilla, successful implant placement is often complicated by the lack of quality and volume of available bone. In these cases, sinus floor augmentation is recommended to gain sufficient bone around the implants. Sinus elevation can be performed by either an open lateral window approach or by a closed osteotome approach depending on available bone height. This case series demonstrates the feasibility and safety of minimally invasive antral membrane balloon elevation, followed by bone augmentation and implant fixation in 20 patients with a residual bone height of 2 to 6 mm below the sinus floor. The surgical procedure was performed using a flapless approach. At 18 months follow-up, the implant survival rate was 100%. Absence of patient morbidity and satisfactory bone augmentation with this minimally invasive procedure suggests that minimally invasive antral membrane balloon elevation should be considered as an alternative to some of the currently used methods of maxillary bone augmentation.     

Computed tomography-guided transfacial buccal space core biopsy of deep head and neck space lesions: our experience

Deep head and neck space lesions can present a number of diagnostic challenges due to their deep anatomical position and difficult access for diagnostic tissue sampling. We describe a series of percutaneous ‘transfacial’ buccal space computed tomography (CT)-guided core biopsies of these lesions and subsequent histological findings. Six patients underwent CT-guided core biopsy of deep parotid, parapharyngeal, or masticator space lesions over a 30-month period. We describe our biopsy technique and correlate our histological findings with subsequent surgical resection where performed. Five of six of CT-guided biopsies obtained sufficient tissue for histological interpretation with varying findings, including salivary gland tumours and squamous cell carcinoma confirmed on subsequent resection. One patient was treated palliatively following core biopsy. No biopsy-related complications were observed. In our small series, percutaneous CT-guided transfacial biopsy via the buccal space has proved an excellent option for the minimally invasive tissue acquisition of deep head and neck space lesions.     

Minimally invasive tibial bone harvesting under intravenous sedation.

PURPOSE: Collecting high amounts of autogenous bone often results in considerable donor site morbidity. The hypothesis evaluated with this prospective study is that a modified approach for tibial bone harvesting using a minimally invasive access under local anesthesia plus sedation in an office setting compares favorably in terms of amount of bone harvested, morbidity, and patient satisfaction with more aggressive approaches previously reported. PATIENTS AND METHODS: Thirty-eight patients (18 women, 10 men) were treated using this method and followed prospectively. A medial approach to the proximal tibia was performed in all cases. A 10 mm incision gives access to an 8 mm manual trephine, which creates a bony window. Cancellous bone is released from the proximal compartment and a bone filter connected to suction allows fast removal of bone particles. Amount of bone harvested (compressed and non-compressed), surgical time, and complications were recorded. RESULTS: Mean surgical time was 14 minutes (range, 9 to 20 minutes). Volume of compressed cancellous bone ranged between 18 and 30 cc (mean, 28 cc). CONCLUSION: Tibial bone harvesting through a medial minimally invasive approach with a bone filter yields satisfactory results in terms of bone volume, surgical time, and patient satisfaction.     

数字化导板引导技术辅助微创治疗前牙钙化根管

结合数字化导板技术及微创车针，建立数字化导板技术引导微创治疗钙化根管的临床方法。     

Internal sinus manipulation (ISM) procedure: a technical report

Background The sinus augmentation procedure has facilitated dental implant treatment in the posterior maxilla where there is insufficient bone for implant placement. A modified Caldwell‐Luc, lateral window technique can be applied in most cases needing sinus augmentation in order to create a larger bone volume. However, treatment morbidity can be a concern, especially in the form of postoperative swelling due to surgical trauma. Vertical augmentation using osteotomes has also been selected as a choice of treatment due to less invasive surgery and less postoperative trauma. Although the osteotome technique enables the surgeon to raise the sinus membrane internally through an implant osteotomy site, the quantity and predictability of bone augmentation can be limiting due to the elasticity of the Schneiderian sinus membrane, difficulty of the membrane to separate from the floor as well as the inability to have direct tactile access to “peel” the membrane off of the floor. Purpose The objective of this report is to present a new, minimally invasive sinus augmentation technique, called the Internal Sinus Manipulation (ISM) procedure, which has been developed to facilitate sinus floor augmentation while reducing treatment morbidity and yet have direct tactile access to raise the membrane off of the sinus floor. Surgical Technique Access to the Schneiderian sinus membrane is achieved without perforation of the membrane through a conventional osteotomy drilling procedure alone or combined with osteotome technique, followed by reflection of the membrane utilizing special ISM instrumentation and bone graft procedure laterally and vertically through the osteotomy site. A planned implant is then placed. Conclusion The Internal Sinus Manipulation procedure can be used as an alternative treatment modality for sinus augmentation as compared to the external lateral window technique while reducing postoperative morbidity for the patients who need implant treatment in posterior maxillary areas.     

CAD/CAM-generated high-density polymer restorations for the pretreatment of complex cases: a case report

Complex rehabilitations represent a particular challenge for the restorative team, especially if the vertical dimension of occlusion (VDO) needs to be reconstructed or redefined. The use of provisional acrylic or composite materials allows clinicians to evaluate the treatment objective over a certain period of time and therefore generates a high predictability of the definitive rehabilitation in terms of esthetics and function. CAD/CAM technology enables the use of prefabricated polymer materials, which are fabricated under industrial conditions to form a highly homogeneous structure compared with those of direct fabrication. This increases long-term stability, biocompatibility, and resistance to wear. Furthermore, they offer more suitable CAD/CAM processing characteristics and can be used in thinner thicknesses than ceramic restorative materials. Also, based on the improved long-term stability, the transfer into the definitive restoration can be divided into multiple treatment steps. This article presents different clinical cases with minimally invasive indications for CAD/CAM-fabricated temporary restorations for the pretreatment of complex cases.     

Individually Prefabricated Prosthesis for Maxilla Reconstuction.

The reconstruction of maxillofacial bone defects by the intraoperative modeling of implants may reduce the predictability of the esthetic result, leading to more invasive surgery and increased surgical time. To improve the maxillofacial surgery outcome, modern manufacturing methods such as rapid prototyping (RP) technology and methods based on reverse engineeing (RE) and medical imaging data are applicable to the manufacture of custom-made maxillary prostheses. After acquisition of data, an individual computer-based 3D model of the bony defect is gernerated. These data are tranferrred into RE software to create the prosthesis using a computer-aided design (CAD) model, which is directed into the RP machine for the production of the physical model. The precise fit of the prosthesis is evaulated using the prosthesis and skull model. The prosthesis is then directly used in investment casting such as "Quick Cast" pattern to produce the titanium model. In the clincical reports presented here, reconstructions of two patients with large maxillary bone defects during the operations, and surgery time was reduced. These cases show that the prefabrication of a prosthesis using modern manufacturing technology is an effective method for maxillofacial defect reconstruction.     

Minimally invasive subnasal elevation and antral membrane balloon elevation along with bone augmentation and implants placement

Atrophic edentulous anterior maxilla is a challenging site for implant placement and has been successfully treated surgically by anterior maxillary osteoplasty. This procedure is associated with considerable discomfort, morbidity, and cost-and consequently reduced patient acceptance. The efficacy and safety of minimally invasive bone augmentation of the posterior maxilla has not been extended thus far to the anterior subnasal maxilla. We present 2 representative cases in which minimally invasive subnasal floor elevation was performed along with minimally invasive antral membrane balloon elevation. Both segments underwent bone grafting and implant placement during the same sitting. Minimally invasive anterior maxilla bone augmentation appears to be feasible. Designated instruments for alveolar ridge splitting and nasal mucosa elevation are likely to further enhance this initial favorable experience.     

The accuracy of fine needle aspiration cytology in the clinical diagnosis of minor salivary gland tumours

The objective of this study was to investigate the accuracy of fine needle aspiration cytology (FNAC) and biopsy for the clinical diagnosis of minor salivary gland tumours (MSGTs). This retrospective study of 32 MSGT cases was conducted over a 5-year period. Clinical features including age, sex, and location of the tumour were obtained from the patient clinical records. All cases were also assessed histologically according to the 2017 World Health Organization Classification of Head and Neck Tumours. The results of FNAC and biopsy were correlated with those of histopathology, and their sensitivity, specificity, and diagnostic efficacy were calculated using histopathology as the gold standard. Eighteen malignant MSGTs (56.3%) and 14 benign MSGTs (43.8%) were diagnosed by pathological diagnosis. The most common malignant tumour was mucoepidermoid carcinoma (seven cases, 38.9%). Most benign cases were pleomorphic adenomas (13 cases, 92.9%). FNAC was performed for 23 cases and biopsy for 13 cases. The sensitivity and specificity of FNAC were 66.7% and 91.0%, respectively, while those of biopsy were 90.0% and 100.0%, respectively. Although FNAC is a minimally invasive and cost-effective procedure, it is less accurate than biopsy in the assessment of MSGTs. Repeated FNAC or biopsy should be considered in negative and unsatisfactory FNAC cases.     

基于配准技术的微创牙种植导向模板的制作方法及应用

目的设计制作精确的微创牙种植导向模板,以指导医生准确地手术定位。方法对行种植手术的患者下颌骨进行CT扫描,依据CT数据构建三维牙颌模型,并利用Simplant专业种植软件在三维模型的基础上进行模拟种植,确定种植体的位置和深度。对牙颌石膏模型进行数字化扫描,通过曲率配准技术将石膏模型和CT三维模型进行对齐,确定种植体设计位置与牙颌扫描模型的关系,根据种植体位置,在牙颌石膏数字化模型上利用3-Matic软件完成导向模板的设计,最后利用快速成型技术制作导向模板。结果通过配准技术将CT数据与牙颌数字化数据相融合,设计出的微创导板定位精确,在无需切开口腔黏膜的情况下依然能够很好地为医生在实际种植时提供导向。结论将三维配准技术应用于种植领域,结合Simplant模拟种植和快速成型等技术制作的微创种植导向模板定位准确,实现了手术的微创性与精确性,值得临床推广使用。     

Guided Endodontic Access of Calcified Anterior Teeth

Pulp canal calcification is characterized by the deposition of calcified tissue along the canal walls. As a result, the root canal space can become partially or completely obliterated. Recently, “guided endodontics” has been reported as an alternative solution in cases of partial or completed canal obliteration. Although this technique can enhance minimally invasive access to the calcified canal, it has been shown that the incisal surfaces are often removed during the access of anterior teeth. This report describes 2 cases of guided endodontics using conventional palatal access in calcified anterior teeth and discusses the applicability of this approach in cases of pulp canal calcification with apical periodontitis and acute symptoms. The method demonstrated high reliability and permitted proper root canal disinfection expeditiously, without the unnecessary removal of enamel and dentin in the incisal surface.     

PRESS and Piezo Microsurgery (Bony Lid): A 7-Year Evolution in a Residency Program Part 1: Surgeon-defined Site Location

IntroductionTreatment of a failing endodontic procedure via microsurgical revision presents better outcomes due, in part, to the integration of the surgical operating microscope (SOM) and cone-beam computed tomography (CBCT) into clinical practice. But challenges still remain with respect to the operational locations and the techniques required to address them. Posterior sites, with substantial cortical plate thicknesses and sensitive anatomy, present the dichotomy of visualization versus postsurgical regeneration of bone. The bony lid technique bridges the gap between these 2 concepts, and the application of piezosurgery renders a precise and biocompatible osseous incision. The purpose of this paper was to outline, through case reports, the progression of piezo-guided surgery in a postgraduate resident setting.MethodsThe primary evolution of the bony lid technique relied on the transfer of measurements from defined landmarks in the CBCT volume to the cortical plate of the surgical site. The secondary evolution used the same measurement protocols transferred to a laboratory model of the patients' arch. A vacuformed stent was fabricated with pertinent fiducial markers in gutta percha defining the surgical site parameters, and a scan exposed with the stent in place. These 2 evolutions are designated as the surgeon-defined site location method and are explained in greater detail in this the first of 2 parts of the topic. All surgeries were executed using the piezosurgical method with increasing levels of guidance and precision throughout the evolution process.ResultsEach step in the technique implementation enabled the resident to assimilate a new technique and skill set while maintaining bone architecture and minimizing volume loss postoperatively. The patient benefits were an increase in intraoperative safety and postoperative comfort. The resident benefits were accelerated regeneration timetables, and increase in the confidence level of the resident and number of scheduled posterior surgical procedures.ConclusionsThe progression from crude on-site measurements to elegant and precise surgical guides enabled the access and manipulations of difficult surgical sites without compromising visibility, postoperative osseous regeneration, or patient comfort.