Revisiting major anatomical risk factors of maxillary sinus lift and soft tissue graft harvesting for dental implant surgeons.

The anatomical variations of the maxillary sinus septa, greater palatine artery, and posterior superior alveolar arteries might cause unexpected complications when they are damaged. Dentists who know these structures well might hope to learn more practical knowledge to avoid and assess injury preoperatively. Therefore, this review paper aimed to review the reported anatomy and variations of the maxillary sinus septa, greater palatine artery/nerve, and posterior superior alveolar artery, and to discuss what has to be assessed preoperatively to avoid iatrogenic injury. To assess the risk of injury of surgically significant anatomical structures in the maxillary sinus and hard palate, the operator should have preoperative three-dimensional images in their mind based on anatomical knowledge and palpation. Additionally, knowledge of the average measurement results from previous studies is important.

Coexistence of frontal sinus hypoplasia with maxillary sinus hypoplasia: a radiological study.

The goal of this study was to determine whether frontal sinus hypoplasia coexists with maxillary sinus hypoplasia. Analyzing paranasal CT scans retrospectively, we included 86 patients who had a hypoplastic maxillary sinus at least on one side and 80 patients with bilateral normal maxillary sinuses (control group). We classified hypoplastic maxillary sinuses using the classification system previously defined by Bolger et al. (Otolaryngol Head Neck Surg 103(5):759-765, 1990). We classified the frontal sinuses as aplastic, hypoplastic, medium-sized, and hyperplastic; as previously defined by Guerram et al. (Am J Phys Anthropol 154(4):621-627, 2014). We compared the presence of frontal sinus hypoplasia using Chi-square test between the groups. The mean age of the maxillary sinus group was 43.2 (range 18-84) years. Of 86 patients, 33 (38.4%) had unilateral and 53 (61.6%) had bilateral maxillary sinus hypoplasia. Of 139 maxillary sinuses totally included, 73 (52.5%) were type 1, 51 (36.7%) were type 2 and 15 (10.8%) were type 3 hypoplastic maxillary sinuses. Of 332 frontal sinuses totally included, 25 (7.5%) were aplastic, 32 (9.6%) were hypoplastic, 172 (51.9%) were medium-sized, and 103 (31%) were hyperplastic. Of 86 patients with a hypoplastic maxillary sinus at least on one side, 29 (33.7%) had a hypoplastic and/or aplastic frontal sinus, while 10 (12.5%) had a hypoplastic and/or aplastic frontal sinus at least on one side in control group. Incidence of frontal sinus hypoplasia and/or aplasia was significantly higher in patients with maxillary sinus hypoplasia compared to the patients with bilaterally normal maxillary sinuses (χ2 = 10.384, P = 0.001). Maxillary sinus hypoplasia has a significantly higher coexistence with frontal sinus hypoplasia. This study may have an implication for anatomical studies about the development of the paranasal sinuses and paranasal sinus surgery as well as further morphological studies.

Localization of orbit in patients with maxillary sinus hypoplasia: a radiological study.

PURPOSE: We aimed to investigate the medial and inferior localization of orbit in patients with maxillary sinus hypoplasia using paranasal computerized tomography. METHODS: We included 76 patients who had a hypoplastic maxillary sinus at least on one side, and 76 patients with normal maxillary sinuses (control group). To assess the localization of orbit, we measured the distances from middle meatal antrostomy point to medial border of orbital medial wall and to the lower border of orbital floor in all patients. We performed statistical comparisons between the groups. RESULTS: Of 76 patients, 26 (34.2%) had unilateral and 50 (65.8%) had bilateral maxillary hypoplasia. Of 126 maxillary sinuses, 70 (55.6%) was type 1, 42 (33.3%) was type 2 and 14 (11.1%) was type 3 hypoplastic. The mean distance from antrostomy point to lamina papyracea was 4.36 ± 2.62 mm in the hypoplasia group, and 1.08 ± 1.7 mm in the control group. The mean distance from antrostomy point to orbital floor was 1.53 ± 1.73 mm in the hypoplasia group, and 1.87 ± 1.96 mm in the control group. Lamina papyracea showed a significant medial localization in the maxillary hypoplasia group as compared to the control group (p < 0.001). CONCLUSION: The orbit has a medial localization in patients with maxillary sinus hypoplasia resulting in a higher complication risk during endoscopic sinus surgery.

Ectopic Infra Orbital Nerves: Case Series of a Dangerous Normal Variant.

Normal variations in the paranasal sinus region are well documented in literature. We present five cases of a little known normal variant, which can have serious implications for the patient as well as the operating surgeon. An ectopic infra orbital nerve canal coursing through the maxillary sinus has rarely been described in imaging literature. This may sometimes be mistaken for a simple septum in the maxillary sinus and may cause serious complications during Functional Endoscopic sinus surgery (FESS) surgeries. We describe the imaging findings and present a brief review of the previous publications on the same subject.

The effect of the presence of the accessory maxillary ostium on the maxillary sinus.

This study was conducted to investigate the presence of the accessory maxillary ostium and its effects on the maxillary sinus, and the concurrent occurrence of morphological variations of neighboring anatomical structures. This study was performed in a tertiary referral center. This is a cross-sectional retrospective study that evaluated coronal CTs of patients to determine the frequency of the accessory maxillary ostium and investigated any simultaneous morphological variations in neighboring anatomical structures. The presence of the accessory maxillary ostium (AMO) plus any concurrent morphological variations of neighboring structures were investigated in 377 patients, with 754 sides. AMO was found to be present in 19.1 % (72/377) of the patients. A concurrent mucus retention cyst was found to be statistically significant on both sides (right side: p = 0.00, left side: p = 0.00), as well as mucosal thickening (right side: p = 0.00, left side: p = 0.00), and maxillary sinusitis (right side: p = 0.04, left side: p = 0.03). No other concurrent variations of statistical significance were detected in the neighboring structures. Our study demonstrated that with the presence of AMO, the likelihood of encountering a mucus retention cyst (48.6 %) had an approximately threefold increase, and that of encountering mucosal thickening (43.0 %) and maxillary sinusitis (29.1 %) had a twofold increase.

Silent sinus syndrome an acquired condition and the essential role of otorhinolaryngologist consultation: a retrospective study.

The silent sinus syndrome (SSS) is a rare clinical entity characterized by painless spontaneous enophthalmos, hypoglobus, and facial deformities secondary to chronic maxillary sinus atelectasis. The aim of this study was to present an SSS diagnostic feature and evaluate the relationship between nasal septum deviation and maxillary sinus volume. A retrospective chart review of the clinical characteristics of 20 patients diagnosed with SSS between January 2013 and July 2014 were analyzed by the Department of Otorhinolaryngology of University Hospital Complex of Santiago de Compostela. 14 patients were females and six males. The mean age was 43 years (range 28-67 years). The right maxillary sinus was involved in 12 patients and the left maxillary sinus in eight patients. There was no statistical difference between gender and the presence of SSS. Maxillary sinus sizes were significantly smaller on the same side as the deviation (p < 0.01). 14 patients were treated with functional endoscopic sinus surgery (FESS) with maxillary antrostomy. We concluded that patients with SSS usually present with facial asymmetry, and the best approach to document and show all facial asymmetries for these patients are the frontal and craneo-caudal photographs. The present study demonstrates that, in adult patients, SSS generally presents a septal deviation to the affected maxillary sinus. We recommend performing a paranasal sinus CT scan when the patient has a deviated nasal septum, retraction of the malar eminence (evidenced from the viewpoint cranio-caudal facial) and hypoglobus. FESS performing postero-anterior uncinectomy and enlargement of the maxillary ostium is recommended to restore sinus pressure and prevent progression of the enophthalmos, hypoglobus and facial deformities.

Infraorbital canal bilaterally replaced by a lateroantral canal.

The infraorbital canal (IOC) normally courses above the maxillary sinus in the orbit floor. During a retrospective study of cone beam computed tomography (CBCT) scans, we found a previously unknown variant of the IOC. The IOCs were absent, being replaced by lateroantral canals coursing around and not above the maxillary sinus to open at infraorbital foramina which were located above the second upper premolar teeth. On coronal multiplanar reconstructions, the lateroantral canals were located anatomically at the outer limit of the zygomatic recess of each maxillary sinus, while the upper wall of the sinus was devoid of any canal. Such rare variant should be kept in mind by dental practitioners and surgeons, as it can determine modifications of common procedures. In this regard, the anatomy of maxilla, as well as mandible, should be evaluated in CBCT on a case-by-case basis.

Anatomic variations of paranasal sinuses-clinical case report.

This article describes the clinical case of an 86-year-old female patient with an asymptomatic clinical condition, without presenting a history of previous traumatisms. When routine radiographic exam-panoramic radiograph-was performed, the following extensions of the paranasal sinuses were found: maxillary sinus (palate), sphenoid sinus (pterygoid process, major wing, and anterior clinoid process), and supraorbital portion of the frontal sinus. Thus computerized tomography was performed to confirm the diagnosis.

Occurrence of maxillary sinus abnormalities detected by cone beam CT in asymptomatic patients.

BACKGROUND: Although cone beam computed tomography (CBCT) images of the maxillofacial region allow the inspection of the entire volume of the maxillary sinus (MS), identifying anatomic variations and abnormalities in the image volume, this is frequently neglected by oral radiologists when interpreting images of areas at a distance from the dentoalveolar region, such as the full anatomical aspect of the MS. The aim of this study was to investigate maxillary sinus abnormalities in asymptomatic patients by using CBCT. METHODS: 1113 CBCT were evaluated by two examiners and identification of abnormalities, the presence of periapical lesions and proximity to the lower sinus wall were recorded. Data were analyzed using descriptive statistics, chi-square tests and Kappa statistics. RESULTS: Abnormalities were diagnosed in 68.2% of cases (kappa = 0.83). There was a significant difference between genders (p < 0.001) and there was no difference in age groups. Mucosal thickening was the most prevalent abnormality (66%), followed by retention cysts (10.1%) and opacification (7.8%). No association was observed between the proximity of periapical lesions and the presence and type of inflammatory abnormalities (p = 0.124). CONCLUSIONS: Abnormalities in maxillary sinus emphasizes how important it is for the dentomaxillofacial radiologist to undertake an interpretation of the whole volume of CBCT images.

[Maxillary sinus septa. Prevalence and anatomy]. / Les septums du sinus maxillaire. Prévalence et anatomie au travers d'une revue de la littérature de 1980 à 2009.

BACKGROUND: Maxillary sinus septa may complicate sinus elevation procedures, especially when they are not diagnosed prior to surgery. The authors had for aim to review published data, to analyze the etiology, the prevalence, the localization, and the size of maxillary sinus septa, and to determine what were the best preoperative radiological examinations. PATIENTS AND METHODS: The Medline search was made with keywords such as "maxillary sinus anatomy, maxillary sinus augmentation, maxillary sinus septa, sinus graft/complications, dental implants". The search was limited to studies published in English from 1980 to January 2009. RESULTS: Twenty-two articles were analyzed. The prevalence of maxillary sinus septa ranged between 14.3% and 33.3%. There was no specific geographic distribution within the sinuses. The mean heights of septa ranged between 2.8 and 8.1 mm. DISCUSSION: It is recommended to systematically use preoperative CT or CBCT scan imaging because of the prevalence, the variable anatomy, and the bad contribution of conventional X-rays.

Partial congenital arrhinia: never seen before adult presentation.

BACKGROUND: Arrhinia is defined as the partial or complete absence of the nasal structures. It is a defect of embryonal origin and can be seen in association with other craniofacial anomalies, central nervous system anomalies, absence of paranasal sinuses, and other palatal and ocular abnormalities. Very few patients with arrhinia have been reported so far in the history of modern medicine. CASE REPORT: This study reports an adult patient with congenital partial arrhinia and reviews the literature along with the embryological basis of such a rare disease. CONCLUSION: Arrhinia is a medical condition with scarce documentation in the literature. This article presents the clinical as well as radiological features of this rare entity.

Combined aplasia of sphenoid, frontal, and maxillary sinuses accompanied by ethmoid sinus hypoplasia.

OBJECTIVE: To report the case of a woman who had combined aplasia of sphenoid, frontal, and maxillary sinuses accompanied by ethmoid sinus hypoplasia. METHODS AND RESULTS: A 47-year-old woman presented with complaints of headache, nasal obstruction, and postnasal drainage. She had no previous history of either facial trauma or systemic diseases affecting the skeletal system. She had a history of functional endoscopic sinus surgery twice in an other institution. However, the surgeries did not significantly alter her symptoms. Coronal and axial computed tomographic scans of the nose and the paranasal sinuses showed poorly developed frontal, sphenoid sinuses, ethmoid cells, and very severe and profound hypoplasia (aplasia) of bilateral maxillary sinuses. CONCLUSIONS: To our knowledge, this patient seems to be the first case having combined aplasias of the sphenoid, frontal, and maxillary sinuses with hypoplastic ethmoid cells without any systemic or skeletal disease.

Maxillary sinus septa: a systematic review.

This review analyzes articles published on the presence of septa in maxillary sinuses. An automated search was conducted on PubMed using different key words. This search resulted in 11 papers in which the presence of antral septa was assessed. These septa are barriers of cortical bone that arise from the floor or from the walls of the sinus and may even divide the sinus into two or more cavities. They may originate during maxillary development and tooth growth, in which case they are known as primary septa; or they may be acquired structures resulting from the pneumatization of maxillary sinus after tooth loss, in which case they are called secondary septa. Several methods have been used in their study, direct observation on dried skulls or during sinus lift procedures; and radiographic observation using panoramic radiographs or computed tomographs. Between 13 and 35.3% of maxillary sinuses have septa. They can be located in any region of the maxillary sinus and their size can vary between 2.5 and 12.7 mm in mean length. Some authors have reported a higher prevalence of septa in atrophic edentulous areas than in non-atrophic ones. If a sinus lift is conducted in the presence of maxillary sinus septa, it may be necessary to modify the design of the lateral window in order to avoid fracturing the septa.

Prevalence and morphological variations of maxillary sinus septa in different age groups: a CBCT analysis.

BACKGROUND: There are limited data from Saudi Arabia on the prevalence and characteristics of maxillary sinus septa. OBJECTIVE: Determine the prevalence and morphological characteristics of septa in the maxillary sinus and their relationship to gender and age using cone beam computed tomography (CBCT). DESIGN: Cross-sectional SETTING: CBCT images acquired from the maxillofacial radiology department in a dental school. PATIENT AND METHODS: CBCT scans of 1010 maxillary sinuses from 505 patients were analyzed to determine the prevalence, location, type, and orientation of maxillary sinus septa. Descriptive statistics, chi-square tests and t tests were used to analyze the data. MAIN OUTCOME MEASURES: The prevalence, location, type, and orientation of maxillary sinus septa. SAMPLE SIZE: 1010 sinuses from 505 patients. RESULT: Approximately 46% of the studied patients had maxillary septa, which were present in 370 (37%) sinuses. About 64% of the septa were present on the right side and 85.7% of all septa were mediolater-ally oriented. The mean height of the septa was 6.06 mm (0.84) in the right sinuses and 5.70 mm (0.93) in the left sinuses. Multiple septa were found in 101 patients (20%). Among males, 58.5% had septa compared to 34% of females (P<.001.) A significant positive association was found between age and the presence and number of septa, P<.001. CONCLUSIONS: Maxillary sinus septa were highly prevalent with various heights and directions among the studied sample. Careful assessment of different anatomic variation must be conducted prior to any maxillary sinus augmentation, particularly in older patients. LIMITATIONS: Cross-sectional evaluation of CBCT images from one dental school patient population; thus, the findings cannot be generalized to other populations. CONFLICT OF INTEREST: None.

Maxillary Sinus Pneumocele Presenting as Aesthetic Deformity: A Case Report With Literature Review.

We report an interesting case of maxillary sinus pneumocele that presented with aesthetic deformity and completely treated with Caldwell-Luc approach and thoroughly review all of the past literature focusing on clinical symptoms and surgical approach. Based on our comprehensive review of maxillary sinus pneumocele, we found 2 important characteristics. First, maxillary sinus pneumocele may be asymptomatic but cause various symptoms owing to the displacement of neighboring structures, such as facial symptoms, eye symptoms, and nasal obstruction. Second, there is no standard operation technique for maxillary sinus pneumocele, but surgical approach should be individualized depending on patient's symptoms and needs. Therefore, more case studies are needed to confirm this.

Hemifacial microsomia. A report of two cases.

Hemifacial microsomia (HFM) is an asymmetrical congenital deformity of the head and face caused by anomalous development of the structures derived from the first and second branchial arches. Oral and maxillofacial malformations present diagnostic and treatment challenges unique to the dental profession. The etiology, a report of two cases and a brief description of treatment modalities are discussed in this article.

Maxillary sinus pain with radiolucent sinuses due to agenesis of the membranous ostium.

INTRODUCTION: The absence of opacities on CT scan usually eliminates paranasal sinus disease as a cause of facial pain. The authors report a case, which constitutes an exception to this general rule, corresponding to a new aetiology of sinus pain. CASE REPORT: A 16-year-old boy presented with very painful "recurrent acute sinusitis" triggered by pressure changes (altitude, diving, surfing), with no sinus opacity on CT scan. Surgical exploration demonstrated absence of a primary or accessory maxillary ostium. Middle meatus antrostomy relieved the patient's pain. DISCUSSION: The pathophysiology of this case of recurrent acute pseudo-sinusitis and the efficacy of antrostomy can be explained by the evo-devo theory of the origin and function of the paranasal sinuses. This case illustrates the absence of communication in the ethmoid of the membranous sac lining the maxillary sinus, formed by degeneration of the maxillary erythropoietic bone marrow. Under stable environmental conditions, the continuous production of nitric oxide by the sinus epithelium is eliminated by simple transmembrane diffusion, but is insufficiently eliminated in the case of rapid pressure changes, inducing sometimes very severe sinus pain, mimicking sinusitis. This case report paves the way for more detailed studies on the role of the paranasal sinuses in facial disease and respiratory physiology.

Elevación de seno transcrestal con inserción de implantes ultracortos de 4.5 mm de longitud en zonas maxilares posteriores con hueso residual menor o igual a 3 mm de altura / Transcrestal sinus lift with insertion of 4.5 mm long ultrashort implants in posterior maxillary areas with residual bone less than or equal to 3 mm in height

Introducción: La atrofia posterior del maxilar con la neumatización del seno maxilar es un problema frecuente. Los protocolos para rehabilitar esta zona han ido cambiando desde la elevación de seno convencional, hasta la elevación transcrestal. Aun así, existen casos con un volumen óseo disponible en altura muy disminuido que precisan de nuevos procedimientos como los implantes de 4,5 mm. En la siguiente serie de casos clínicos se muestran pacientes tratados con este procedimiento. Material y métodos: Se presenta un estudio retrospectivo en el que se han evaluado implantes de 4,5 mm de longitud, insertados en sectores posteriores maxilares con una altura ósea residual igual o menor a 3 mm, realizándose al mismo tiempo una elevación de seno transcrestal. Posteriormente, se realiza un seguimiento radiográfico estimándose la pérdida ósea crestal y la supervivencia de los implantes.La variable principal fue la supervivencia del implante y como variables secundarias se registraron la pérdida ósea mesial y distal. Resultados: Fueron reclutados 13 pacientes en los que se insertaron 15 implantes. La media de la altura inicial de la cresta, en el estudio fue de 2,85 mm (+/- 0,20) con un rango entre 2,50 y 3 mm. Los implantes presentaron un seguimiento medio de 13,33 meses tras la carga (+/- 3,09) no encontrándose complicaciones ni fracasos durante este tiempo, por lo que la supervivencia fue del 100%. Conclusiones: Los datos preliminares obtenidos en el presente estudio muestran una alternativa a la elevación de seno mediante ventana lateral con una menor morbilidad para los pacientes. (AU)

Introduction: PPosterior maxillary atrophy with pneumatization of the maxillary sinus is a common problem. The protocols for rehabilitating this area have changed from conventional sinus lift to transcrestal lift. Even so, there are cases with a very low available bone volume in height that require new procedures such as 4.5 mm implants. The following case series shows patients treated with this procedure. Material and methods: A retrospective study is presented in which 4.5 mm long implants inserted in maxillary posterior sectors with a residual bone height equal to or less than 3 mm were evaluated and a transcrestal sinus lift was performed at the same time. Subsequently, a radiographic follow-up was carried out, estimating crestal bone loss and implant survival. The primary variable was implant survival and mesial and distal bone loss were recorded as secondary variables. Results: Thirteen patients were recruited and 15 implants were inserted that met the previously established inclusion criteria. The mean initial ridge height where the implants included in the study were placed was 2.85 mm (+/- 0.20) with a range between 2.50 and 3 mm. No complications related to the surgery were reported in any of the cases. The implants had a mean follow-up of 13.33 months after loading (+/- 3.09) with no complications or failures during this follow-up time, so survival was 100%. Conclusions: Preliminary data obtained in the present study show a predictable alternative to lateral window sinus lift with less morbidity for patients. (AU)

Elevación de seno transcrestal con inserción de implantes ultracortos de 4.5 mm de longitud en zonas maxilares posteriores con hueso residual menor o igual a 3 mm de altura / Transcrestal sinus lift with insertion of 4.5 mm long ultrashort implants in posterior maxillary areas with residual bone less than or equal to 3 mm in height

Introducción: La atrofia posterior del maxilar con la neumatización del seno maxilar es un problema frecuente. Los protocolos para rehabilitar esta zona han ido cambiando desde la elevación de seno convencional, hasta la elevación transcrestal. Aun así, existen casos con un volumen óseo disponible en altura muy disminuido que precisan de nuevos procedimientos como los implantes de 4,5 mm. En la siguiente serie de casos clínicos se muestran pacientes tratados con este procedimiento. Material y métodos: Se presenta un estudio retrospectivo en el que se han evaluado implantes de 4,5 mm de longitud, insertados en sectores posteriores maxilares con una altura ósea residual igual o menor a 3 mm, realizándose al mismo tiempo una elevación de seno transcrestal. Posteriormente, se realiza un seguimiento radiográfico estimándose la pérdida ósea crestal y la supervivencia de los implantes.La variable principal fue la supervivencia del implante y como variables secundarias se registraron la pérdida ósea mesial y distal. Resultados: Fueron reclutados 13 pacientes en los que se insertaron 15 implantes. La media de la altura inicial de la cresta, en el estudio fue de 2,85 mm (+/- 0,20) con un rango entre 2,50 y 3 mm. Los implantes presentaron un seguimiento medio de 13,33 meses tras la carga (+/- 3,09) no encontrándose complicaciones ni fracasos durante este tiempo, por lo que la supervivencia fue del 100%. Conclusiones: Los datos preliminares obtenidos en el presente estudio muestran una alternativa a la elevación de seno mediante ventana lateral con una menor morbilidad para los pacientes. (AU)

Introduction: PPosterior maxillary atrophy with pneumatization of the maxillary sinus is a common problem. The protocols for rehabilitating this area have changed from conventional sinus lift to transcrestal lift. Even so, there are cases with a very low available bone volume in height that require new procedures such as 4.5 mm implants. The following case series shows patients treated with this procedure. Material and methods: A retrospective study is presented in which 4.5 mm long implants inserted in maxillary posterior sectors with a residual bone height equal to or less than 3 mm were evaluated and a transcrestal sinus lift was performed at the same time. Subsequently, a radiographic follow-up was carried out, estimating crestal bone loss and implant survival. The primary variable was implant survival and mesial and distal bone loss were recorded as secondary variables. Results: Thirteen patients were recruited and 15 implants were inserted that met the previously established inclusion criteria. The mean initial ridge height where the implants included in the study were placed was 2.85 mm (+/- 0.20) with a range between 2.50 and 3 mm. No complications related to the surgery were reported in any of the cases. The implants had a mean follow-up of 13.33 months after loading (+/- 3.09) with no complications or failures during this follow-up time, so survival was 100%. Conclusions: Preliminary data obtained in the present study show a predictable alternative to lateral window sinus lift with less morbidity for patients. (AU)