Effects of Pterygomaxillary Separation on Skeletal and Dental Changes After Surgically Assisted Rapid Maxillary Expansion: A Single-Center, Double-Blind, Randomized Clinical Trial.

PURPOSE: Surgically assisted rapid maxillary expansion (SARME) is a procedure routinely performed to correct transverse maxillary deformities and can be performed with or without pterygomaxillary disjunction (PD). The aim of the present study was to measure the effect of the amount of expansion and stability of SARME with or without PD. PATIENTS AND METHODS: We designed and implemented a double-blind, randomized clinical trial. The patients were randomly assigned to 2 groups: group 1, SARME without PD; and group 2, SARME with PD. Cone-beam computed tomography scans were performed at 3 points: baseline (T0), after maxillary expansion (T1), and at the end of the retention period (T2). Dental and bone expansion and dental inclination at the maxillary canine and first molar regions were assessed. Two-way repeated measures analysis of variance was used to evaluate the differences between the 2 groups at the 3 evaluation periods (T0, T1, and T2), using a level of significance of P < .05. RESULTS: A total of 24 patients underwent maxillary surgical expansion (group 1, n = 12; and group 2, n = 12). Both techniques promoted a significant transverse dental expansion in the first molar at T2 (with PD, 5.4 mm; vs without PD, 6.4 mm; change, -6.18 mm to 1.48 mm). However, no statistically significant differences were observed between the 2 groups. The tipping molars at T2 remained at a higher level in the SARME, no PD group than in the SARME, PD group (with PD, 2.3°; vs no PD, 4.6° for 3 teeth; change, -12.72° to 5.57°; and with PD, 1.6° vs without PD, 3.6° for 14 teeth; change, -9.96° to 9.83°). CONCLUSIONS: SARME with and without PD is a reliable method for obtaining maxillary expansion, with slight differences in the patterns of skeletal and dental alterations.

Primitive Squamous Cell Carcinoma of Pterygopalatine Fossa.

Primitive tumors of pterygopalatine fossa (PPF) are often benign tumors or extension of a malignant sinonasal tract. Primitive tumors may rarely occur in PPF.The authors present a 71-year-old woman with a 6-month history of left cranial nerve palsy. Magnetic resonance imaging and positron emission tomography-computed tomography showed an enhancing isolated lesion at the PPF. A transmaxillary biopsy was performed, leading to diagnosis of primitive squamous cell carcinoma. The patient underwent radiotherapy treatment.Primitive tumors of PPF are rare and diagnosis may be difficult. Endoscopic access for diagnosis can be performed. Squamous cell carcinoma occurring in PPF is associated with poor prognosis.

Clarifying the mechanism of effect of the Bionator for treatment of maxillary protrusion: A percentile growth study.

AIM: The reported effects of Bionator treatment in patients with mandibular retrognathism are conflicting. This study evaluated the changes in craniofacial morphology resulting from treatment with a Bionator, based on measurement percentiles previously reported, to clarify the mechanism of the effect of this commonly used functional device. MATERIALS AND METHODS: Study Design: Retrospective. SETTING: A private orthodontic clinic. PARTICIPANTS: Forty-two children (mean age, 10.13 years) requiring treatment with a Bionator for Class II malocclusion (mandibular retrognathism). Children were randomly assigned to a Bionator group with or without an expansion screw. Measurements on lateral cephalometric radiographs were taken before and upon completion of Bionator treatment. All parameters measured were characterised according to the measurement percentiles previously reported. Each parameter was compared before and after treatment for all patients and for each treatment group using Wilcoxon's test. RESULTS: No significant differences in cranial length or mandibular body length were seen in any of the 3 groups, but anterior cranial base length and maxillary length were significantly decreased while mandibular ramus height and mandibular length were significantly increased after treatment in the Bionator with expansion screw group and in the all-patient group. CONCLUSIONS: The findings suggest that treatment with a Bionator with expansion screw during the growth and development stage results in increased mandible length and ramus height and inhibits the growth of the maxilla and anterior cranial base bone.

Schwannoma of the Sinonasal Tract and the Pterygopalatine Fossa with or without Intracranial Extension.

AIMS: Compared with those in other head and neck regions, schwannomas in the nasal cavity or paranasal sinuses are rare. The aim of this study was to present the experience of the authors in 11 schwannoma cases of the sinonasal tract and pterygopalatine fossa over a decade. METHODS: A retrospective study from 2003 to 2014. RESULTS: Three female and 8 male patients from 22 to 61 years of age (mean age 42 years) were admitted. The most common complaints were unilateral nasal congestion. A total of 10 of the patients received surgery, including 6 functional endoscopic sinus surgeries (FESS). The postoperative course was generally uneventful. Among the patients, 10 remained regionally asymptomatic, and there has been no clinical or radiological evidence of recurrence or residual tumor. CONCLUSION: Surgical treatment is effective for schwannomas of the sinonasal tract and the pterygopalatine fossa with a low recurrence rate. Conducting CT and MRI (particularly fluid-attenuated inversion recovery) before surgery is mandatory. FESS could become the primary treatment of choice.

Displacement and stress distribution of the maxillofacial complex during maxillary protraction with buccal versus palatal plates: finite element analysis.

OBJECTIVES: The aim of this study was to analyse the displacement and stress distribution in the maxillofacial complex during maxillary protraction with buccal and palatal plates using three-dimensional finite element analysis. MATERIALS AND METHODS: Three anchorage appliance models-palatal plate (Type A), miniplate at the infrazygomatic crest (Type B), and conventional tooth-borne appliance (Type C)-were designed and integrated into a skull model. Protraction force was 500 g per side and force direction was forward and 30 degree downward to the maxillary occlusal plane. The stress distribution around the circum-maxillary sutures and the displacement of the surface landmarks were analysed. RESULTS: All models showed forward and upward displacement at anterior nasal spine, Point A, and prosthion and forward and downward displacement at posterior nasal spine resulting in a counter-clockwise rotation. This anterior displacement was greatest in Type A. At the maxillary process of the zygoma, upward movement was shown only in Type A, whereas downward movement was observed in Types B and C. The greatest stresses in Type A were at the pterygomaxillary and the zygomaticotemporal sutures. Type B showed the greatest stress at the frontomaxillary suture. LIMITATIONS: Type A showed asymmetric results; however, it was not of clinical significance. CONCLUSION: The palatal plate resulted in wider stress distribution and more forward displacement compared to miniplate at the infrazygomatic crest area and conventional tooth-borne appliances. It might be recommended to consider the application of the palatal plate for maxillary protraction in Class III patients.

Glenoid fossa position in surgically repaired unilateral cleft lip and palate patients.

BACKGROUND: Relative position of the glenoid fossa would play a significant role in the morphology of lower face. The aim of the present study was to cephalometrically evaluate the position of the glenoid fossa in a group of unilateral cleft lip and palate (UCLP) patients in order to better clarify the role of this craniofacial component in skeletal disharmonies associated with this anomaly. METHODS: Lateral cephalometric radiographs of 59 patients (32 males and 27 females) with surgically repaired UCLP (mean age 19.5±1.4 years) along with an equal number of age and gender matched skeletal Class I controls were analyzed for sagittal and vertical position of the glenoid fossa as well as lower anterior face height (LAFH), mandibular plane and length. RESULTS: Paired samples t-test revealed a statistically significant anterior positioning of the glenoid fossa in UCLP subjects. A more cranial positioning of the glenoid fossa, basion, pterygomaxillary fissure, and posterior nasal spine were also seen to be associated with the cleft group on vertical evaluation. Effective length of mandible was normal with significantly steeper mandibular plane and increased LAFH. LIMITATIONS: Further investigations using three dimensional imaging techniques is necessary for better clinical interpretation. CONCLUSIONS: The glenoid fossa is positioned more cranially and anteriorly in UCLP individuals, clinically contributing to the mandibular prominence and concave facial profile inspite of their mandibular length being normal. Steep mandibular planes and increased LAFH reportedly associated with a cranially positioned glenoid fossa is observed in UCLP patients also.

The nasomaxillary complex and the cranial base in artificial cranial deformation: relationships from a geometric morphometric study.

INTRODUCTION: It is widely accepted that there is a relationship between the cranial base and the development of the nasomaxillary complex (NMC). The objective of the present study was to investigate the morphological relationship between these two anatomical units in skulls that have intentionally been subjected to one of two types of artificial deformity of the cranial vault [artificially deformed skulls (ADS)]. MATERIAL AND METHODS: A geometric morphometry study was performed on lateral cephalometric X-rays of three groups of crania: 32 with anteroposterior (AP) deformity, 17 with circumferential (C) deformity, and 39 with no apparent deformity. RESULTS: The cranial base of the ADS showed marked deformity that produced a restriction of AP growth of the NMC, alterations of the roof of the orbit as a consequence of the rotation of anterior cranial fossa, and nasal protrusion. Pronounced morphological differences were found between the three groups: increased vertical development of the maxilla occurred in both ADS groups due to growth of the alveolar process, and rotation of the maxilla and displacement of the orbital rim was observed in the C group. This confirms that the posterior facial plane is regarded as an axial structure that serves as an interface between the middle cranial base and the NMC (Enlow, D.H. and Hans, M.G. (1996) Essential of Facial Growth. WB Saunders Co., Philadelphia, PA). LIMITATIONS: It is important to take into account that these results have been obtained from an archaeological sample, with all the limitations that this implies such as being a small sample and with no absolute certainty regarding the use of the same type of deforming device within each group. Furthermore, this is a lateral two-dimensional study in which transverse development has not been analysed. CONCLUSIONS: Artificial modification of the shape of the vault has repercussions on the NMC that support the theory of an all-inclusive integration of the different cranial units in normal as well as in restricted development.

Case Report: Fractured Needle in the Pterygomandibular Space Following Administration of an Inferior Dental Nerve Block.

Fortunately, needle fracture is a rare complication following the administration of dental local anaesthetic. We present a case of needle fracture following administration of an inferior dental nerve block. The fractured needle was retrieved successfully under general anaesthetic. We also provide some suggestions on how to prevent needle fracture, and advice on how to manage the situation should it arise. Clinical Relevance: Dental practitioners are the largest user group of local anaesthesia in the UK. It is important that practitioners are aware of the risks to the patient of needle fracture, how to minimize the risk of this occurring and be aware of how to manage the situation should it arise.

[Orbitozygomatic approaches to skull base tumors spreading into the orbit, paranasal sinuses, nasal cavity, and pterygopalatine and infratemporal fossae].

The paper analyzes application of orbitozygomatic approaches at the Department of Skull Base and Craniofacial Surgery of the Burdenko Neurosurgical Institute for a 14-year period. During this time, 723 patients were operated on using the orbitozygomatic approach, which has become the workhorse of surgery for skull base tumors spreading into the orbit, paranasal sinuses, and pterygopalatine and infratemporal fossae. The authors describe seven major modifications of the orbitozygomatic approach that they have used in their practice.

Impact of extensive surgery in multidisciplinary approach of pterygopalatine/infratemporal fossa soft tissue sarcoma.

BACKGROUND: To evaluate a strategy whereby extensive surgery ± external radiotherapy (RT) could improve local control in pterygopalatine/infratemporal fossa (PIF) sarcoma. PROCEDURE: Forty-one patients with a diagnosis of sarcoma involving the PIF and referred to our Institute from 1984 to 2009 were included in the analysis. Patients received multidrug chemotherapy and radiotherapy ± surgery, depending on the period of treatment. RESULTS: The median age at diagnosis was 7.6 years (range: 0.1-22 years). There were 36 RMS, 3 undifferentiated sarcoma and 2 other soft-tissue sarcomas. Sixty-eight percent of patients had meningeal risk factors at diagnosis. Local treatment consisted of RT alone in 19 patients, surgery in combination to RT in 19 patients and surgery alone in 3 patients. The local progression rate (LPR) at 5 years was 45% for the entire population, 59% for the 19 patients treated with RT alone and 34% for the 22 patients who had surgery as part of their treatment. All locoregional failures after extensive surgery occurred at the skull base and/or in leptomeningeal spaces. CONCLUSIONS: Multidisciplinary approach including extensive surgery for PIF sarcoma is feasible and yields good local control with 15/22 patients in local complete remission. Future studies are warranted to confirm these promising results, to evaluate the possibility of avoiding RT or limiting the RT field, and to extend the indication for extensive surgery to other "worse" sites of PM sarcoma such as the paranasal sinuses.

Use of coblation in resection of juvenile nasopharyngeal angiofibroma.

We present a series of 4 patients with juvenile nasopharyngeal angiofibroma (JNA) who underwent Coblation-assisted endoscopic resection after preoperative embolization, and discuss the use and advantages of endoscopic Coblation-assisted resection of JNA. Our limited case series suggests that Coblation may be used in the resection of JNA after embolization in a relatively safe, efficient, and effective manner. Coblation allows for decreased bleeding, less need for instrumentation, and improved visualization. There are limited published data in the literature to date on the use of Coblation in endoscopic JNA resection. We describe its use in a more extensive tumor than those previously reported. Further studies are needed to fully define the safety and utility of Coblation technology for this application.

Surgical approach to the pterygopalatine fossa-comparison between anterior approach and lateral approach.

The anterior and the lateral approach for resecting an invading tumor in the pterygopalatine fossa region were compared. An anterior approach was applied for resecting a malignancy that originated from the maxillary tuberosity, upper hard plate, and maxillary sinus, and a lateral approach was applied for resecting a malignancy that originated from the upper gingiva and buccal mucosa. The anterior approach was capable of exposing the whole maxilla, although it was difficult to achieve such exposure by the lateral approach. However, the submandibular incision technique used in the Dingman approach was useful for upper neck dissection as well as for exposure of the artery and vein to anastomose them for reconstruction. The anterior approach should be useful for resection of the pterygopalatine fossa concomitant with total maxillectomy. On the other hand, the lateral approach might have an advantage in terms of its cosmetic effects.

A giant juvenile nasopharyngeal angiofibroma.

Juvenile nasopharyngeal angiofibromas are locally growing and highly vascular tumors. They are primarily treated through surgical excision ranging from an open approach to an endoscopic approach. We presented a 20-year-old man with a giant juvenile nasopharyngeal angiofibroma that bilaterally obliterated the pterygopalatine fossa, invaded the sphenoid bone, and extended to the left nasal passage. His complaints were epistaxis and nasal obstruction. After embolization, the patient was treated surgically using the endoscopic approach and declared cured and discharged without any complications.

The application of 3-dimensional magnetic resonance imaging in nasopharyngeal carcinoma with pterygopalatine fossa invasion.

OBJECT: The pterygopalatine fossa (PPF) is a covert neurovascular pathway in the skull base and connects with numerous intracranial and extracranial spaces. The aim of this study was to explore the magnetic resonance imaging (MRI) features of PPF invasion in patients with nasopharyngeal carcinoma (NPC). MATERIAL AND METHODS: The medical records of 88 patients with stage T3 or T4 NPC were retrospectively analyzed. The 3-Dimensional (3D) volumetric images of MRI were reconstructed for the tiny connecting conduits of the invaded PPFs in the NPC patients. The infiltration incidence of conduits and connected further structures were calculated. RESULTS: Forty-six PPFs from 37 patients were invaded by NPC. The proportions of stage T4 NPC and intracranial extension were higher in patients with PPF invasion than that without PPF invasion (P < 0.05). Each connecting conduit of the PPF had corresponding optimal reconstructed orientation based on 3D volumetric MRI images. The first three most common infiltrated conduits were palatovaginal canal, vidian canal and sphenopalatine foramen, which were adjacent to the nasopharynx. Among the conduits connecting with further structures, the most common infiltrated conduit was pterygomaxillary fissure, followed by foramen rotundum and inferior orbital fissure. Furthermore, The NPC lesions involved stage T4 structures via the conduits from 19.6% of the invaded PPFs. CONCLUSIONS: The application of high-quality reconstruction images based on 3D sequence of MRI in NPC patients proved to be feasible and beneficial for the manifestation of the invaded PPFs and connecting conduits.

Giant dedifferentiated liposarcoma of the right hemifacial area involving the oral cavity.

Although liposarcoma is a reasonably common soft tissue sarcoma in adults, its occurrence within the head and neck region is very rare. The following report presents the case of a giant dedifferentiated liposarcoma initially located in the temporal region and then extending to the entire right maxillofacial region. Clinical as well as histopathological features and therapeutic approaches of dedifferentiated liposarcoma are discussed, and a literature review is presented.

Decellularized porcine derived membrane (Tarsys®) for correction of lower eyelid retraction.

Retraction of the lower eyelid can be consequence of medical and surgical conditions. Various kinds of allotransplants and biomaterial have been used to correct it; we report on the surgical correction of lower lid retraction with a decellularized porcine derived membrane (Tarsys(®)). A 49-year-old patient with a history of adenoid cystic carcinoma in the pterygo-palatine fossa, requiring extensive surgery and repeated radiotherapy, presented with 6 mm lagophthalmus and exposure keratopathy secondary to facial nerve palsy. The lower lid malposition was corrected with a Tarsys(®) implant. Three months after surgery no lagophthalmos was present and substantial relief of signs and symptoms of ocular surface disease and good symmetry between right and left eye was achieved. If general condition or morbidity in potential donor sites hamper harvesting autologous graft material to support the lower lid, bioengineered xenografts can be used successfully to correct eyelid malpositions such as lower lid retraction.

Coronomaxillary space and its significance in complete denture retention--case reports.

The coronomaxillary space defines the distal-most extension of the maxillary denture border, and it usually is tightened during mouth opening. It has been reported that its adequate filling or overfilling is helpful in prosthesis retention. Two types of individual anatomical variations can affect the size of this space: vertical or lateral. With vertical variations, the space increases or does not vary when the mouth is opened; therefore, the prosthesis border must be thicker to obtain adequate retention. With lateral variations, the coronomaxillary space is reduced when the mouth is opened; therefore, the prosthesis border must be thin. The case reports presented here show how complete denture retention can be augmented by the careful recording of the coronomaxillary space dimensions.

Infra-Temporal and Pterygo-Palatine Fossae Tumors: A Frontier in Endoscopic Endonasal Surgery-Description of the Surgical Anatomy of the Approach and Report of Illustrative Cases.

Infratemporal and pterygopalatine fossae (ITF and PPF) represent two complex paramedian skull base areas, which can be defined as jewelry boxes, containing a large number of neurovascular and osteomuscular structures of primary importance. They are in close communication with many craniofacial areas, such as nasal/paranasal sinuses, orbit, middle cranial fossa, and oral cavities. Therefore, they can be involved by tumoral, infective or inflammatory lesions spreading from these spaces. Moreover, they can be the primary site of the development of some primitive tumors. For the deep-seated location of ITF and PPF lesions and their close relationship with the surrounding functional neuro-vascular structures, their surgery represents a challenge. In the last decades, the introduction of the endoscope in skull base surgery has favored the development of an innovative anterior endonasal approach for ITF and PPF tumors: the transmaxillary-pterygoid, which gives a direct and straightforward route for these areas. It has demonstrated that it is effective and safe for the treatment of a large number of benign and malignant neoplasms, located in these fossae, avoiding extensive bone drilling, soft tissue demolition, possibly unaesthetic scars, and reducing the risk of neurological deficits. However, some limits, especially for vascular tumors or lesions with lateral extension, are still present. Based on the experience of our multidisciplinary team, we present our operative technique, surgical indications, and pre- and post-operative management protocol for patients with ITF and PPF tumors.

Diagnosis and endoscopic management of sinonasal schwannomas.

AIMS: Survey the clinical symptoms, radiological features, management, and long-term outcomes of sinonasal and anterior skull base schwannomas. PATIENTS AND METHODS: Retrospective review of patients with sinonasal schwannomas treated from June 2001 through January 2010 at two academic institutions. RESULTS: There were 4 women and 3 men in this study. The mean age was 46 years (range 17-68). The mean tumor size was 2.4 cm (range 1.4-3.8 cm). Tumor locations included ethmoid sinuses (3), nasal cavity (2) and pterygopalatine fossa (2). Six patients had endoscopic resections, while 1 was approached and resected via a lateral rhinotomy. The mean follow-up was 2.8 years. There were no tumor recurrences during the study period. CONCLUSIONS: Schwannomas of the paranasal sinuses and nasal cavity are uncommon tumors that can usually present with vague and nonspecific symptoms. Magnetic resonance imaging can suggest the diagnosis; however, a definitive diagnosis is made by correlation with histopathological findings. Treatment is complete surgical resection. This study illustrates the effectiveness of the endoscopic endonasal approach in the treatment of these benign tumors.