Cone-beam computed tomography evaluation of maxillary sinusitis

Introduction

Dental pain originating from the maxillary sinuses can pose a diagnostic problem. Periapical lesion development eliciting inflammatory changes in the mucosal lining can cause the development of a sinusitis. The purpose of this study was to describe the radiographic characteristics of odontogenic maxillary sinusitis as seen on cone-beam computed tomography (CBCT) scans and to determine whether any tooth or any tooth root was more frequently associated with this disease.

Methods

Eighty-two CBCT scans previously identified as showing maxillary sinus pathosis were examined for sinusitis of odontogenic origin in both maxillary sinuses.

Results

One hundred thirty-five maxillary sinusitis instances with possible odontogenic origin were detected. Of these, 37 sinusitis occurrences were from nonodontogenic causes, whereas 98 instances were tooth associated with some change in the integrity of the maxillary sinus floor. The average amount of mucosal thickening among the sinusitis cases was 7.4 mm. Maxillary first and second molars were 11 times more likely to be involved than premolars, whereas either molar was equally likely to be involved. The root most frequently associated with odontogenic sinusitis is the palatal root of the first molar followed by the mesiobuccal root of the second molar.

Conclusions

Changes in the maxillary sinuses appear associated with periapical pathology in greater than 50% of the cases. Maxillary first or second molar teeth are most often involved, and individual or multiple roots may be implicated in the sinusitis. The use of CBCT scans can provide the identification of changes in the maxillary sinus and potential causes of the sinusitis.     

Dentofacial effects of two facemask therapies for maxillary protraction: Miniscrew implants versus rapid maxillary expanders

Objective:To compare the dentofacial effects of maxillary protraction with two facemask therapies in growing Class III patients: facemask in association with miniscrew implants (MSI/FM) and facemask with rapid maxillary expanders (RME/FM).Materials and Methods:Forty-three Chinese patients with Class III malocclusion and maxillary deficiency were randomly assigned to a MSI/FM sample of 20 patients and a RME/FM sample of 23 subjects. The changes in dentofacial cephalometric variables from the beginning (T1) to the end of treatment (T2) were compared with t-test for paired samples in both groups and for independent samples between the two groups.Results:No significant cephalometric differences were observed between the two groups in active treatment effects except for maxillary dental variables. However, significant favorable changes in both maxillary and mandibular skeletal components were noted in two groups after treatment. Sagittal measurements showed the maxilla was advanced, mandibular projection was reduced, and the relative sagittal intermaxillary discrepancy improved. Patients experienced additional unfavorable outcomes of clockwise rotation of the mandible as well as retroclination of the lower incisors. The soft tissue profile was improved remarkably in both groups. Proclination of the maxillary incisors and mesialization of the maxillary dentition were significantly different between the two groups. The increases in U1-SN, U1-VR, and U6-VR were 6.41°, 2.78 mm, and 1.24 mm less in the MSI/FM group than in the RME/FM group, respectively.Conclusions:Compared with the RME/FM therapy, the MSI/FM protocol using a smaller magnitude of protraction force improves skeletal relationships and soft tissue profile and reduces the undesired dentoalveolar effects.     

Upper airway assessment using four different maxillary expanders in cleft patients: A cone-beam computed tomography study

Objective:To evaluate the anterior and posterior maxillary width, the nasal passage volume, the oropharyngeal minimum axial area, and volume changes in unilateral cleft lip and palate patients treated with one of the following four expanders: Hyrax, Fan-Type, inverted mini-hyrax supported on the first permanent molars (iMini-M), or inverted mini-hyrax supported on the first premolars (iMini-B).Materials and Methods:A total of 40 patients with transverse maxillary deficiency who were submitted for rapid maxillary expansion were divided in four groups according to type of expander used. Cone-beam computed tomography images were taken before and 3 months after expansion. One-way analysis of variance was used to analyze the differences among the groups, and paired t-tests were used to evaluate the changes in each group.Results:All groups showed a significant increase in the anterior maxillary width, with no intergroup differences. The iMini-B was the only group that did not show a significant increase in the posterior maxillary width. The intergroup comparison demonstrated differences among all groups except between Hyrax and iMini-M, which showed the greatest posterior expansions. The intragroup analysis showed a significant increase in the nasal passage volume in hyrax and inverted mini-hyrax on the molar groups, but the intergroup comparison revealed a significant difference only between Fan-Type and inverted mini-hyrax on the molars. None of the expanders caused significant changes in the oropharyngeal measurements.Conclusions:Only the Hyrax and inverted mini-hyrax on the molar expanders effectively increased the nasal passage volume, and none of the expanders evaluated in this study modified the oropharyngeal airway.     

种植支抗辅助内收前牙后牙槽骨的改建

目的：探讨种植支抗在大幅度内收前牙后牙槽骨的改建状况。方法：12例正畸治疗患者，上牙槽前突，UD—SN、U1-SN大于正常一个标准差，轻度拥挤，正畸需拔除第一前磨牙，以种植支抗辅助内收切牙。其中，男3例，女9例，年龄20～54岁，平均25岁；正畸治疗前、后，分别拍摄头颅CT、三维重建，确定每颗牙的正中矢状面、牙长轴，分别在牙槽嵴、牙根1／2、根尖3个平面，测量每颗前牙的唇、腭侧牙槽骨厚度，分析牙槽骨随牙移动的改建程度。测量数据应用SPSS10．0软件包进行配对t检验。结果：测量数据显示，牙槽嵴区牙槽骨唇侧增厚，舌侧变薄；在根中和根尖处，唇侧变薄，舌侧增厚。牙相对于牙槽骨作倾斜移动，正畸治疗前、后比较，有显著性差异，P〈0．05。牙根尖移向唇侧骨皮质，牙根颈部移向牙槽骨舌侧：在个别牙发现牙根的唇侧骨皮质开窗，根尖明显穿破骨皮质，横断面可见根尖处骨皮质断裂、不连续。结论：种植支抗增强了正畸移动牙的能力，但牙移动中仍无法避免倾斜移动，牙槽骨腭侧致密的骨皮质改建缓慢，限制了牙的移动。在种植支抗辅助正畸治疗中，应避免盲目及过度矫正，造成牙周支持组织永久性损伤。     

口腔种植术前锥形束CT影像评估上颌窦状况

锥形束CT（CBCT）在种植术中具有非常重要的作用,通过CBCT可以了解种植术前术后的情况,判断种植体植入前植入床的基本条件,判断能否进行种植、种植植入方向、方法以及术后评估等。涉及到上颌窦的种植术应常规拍摄CBCT。本文通过临床实例介绍使用CBCT进行种植术前上颌窦分析评估及判断术后可能发生的改变。     

应用CBCT回顾分析牙源性上颌窦病变

［摘要］ 目的 通过回顾CBCT资料评估牙源性上颌窦炎的影像学表现及最易引起牙源性上颌窦炎的牙位。方法 将500例CBCT资料分为正常上颌窦、牙源性上颌窦病变、非牙源性上颌窦病变和无法判断来源的上颌窦病变,并进行统计学分析。结果 牙源性上颌窦炎的影像学表现是发生龋病、不良修复体的上颌后牙或对应牙位有未愈合的拔牙创,无论其是否伴有根尖周病变,该病变牙相应上颌窦底黏膜会呈局部隆突性增厚影像。牙源性上颌窦炎发病率占常人的12.4%,占上颌窦病变病人的48.6%。上颌第一磨牙最易引起牙源性上颌窦炎。发生上颌窦炎,即黏膜增厚>2 mm的病例中,黏膜平均增厚(6.11±4.43) mm。结论 牙源性因素占上颌窦炎发病因素的一半;上颌第一磨牙最易引起牙源性上颌窦炎;CBCT能清晰反映上颌窦的解剖解构及上颌窦炎所引起的变化。     

A comparative study of magnetic resonance imaging versus computed tomography for the evaluation of maxillary and mandibular tumors

The relative value of magnetic resonance imaging (MRI) versus computed tomography (CT) for imaging benign and malignant lesions of the maxilla and mandible was studied in a group of 16 patients. The imaging methods were evaluated for their ability to detect the lesion and define lesion margins, soft tissue extension, and bone involvement. The abnormality was identifiable with both imaging methods. For benign cystic lesions of either the maxilla or mandible (50%), MRI was overall equal to or better than CT. Magnetic resonance imaging was superior to CT in the evaluation of lesion margins and soft tissue extent of disease, whereas it was equal or slightly inferior to CT in lesion detection and in the evaluation of bone involvement. In the imaging of malignant neoplasms (50%), MRI was overall superior to CT in all four categories reviewed. Magnetic resonance imaging also had the highest rate of correlation with clinical findings, either from physical examination or at the time of surgery.     

Nasal soft- and hard-tissue changes following tooth-borne and hybrid surgically assisted rapid maxillary expansion: A randomized clinical cone-beam computed tomography study

PurposeThe aim of this study was to assess the effects of tooth/bone-borne (hybrid) and tooth-borne (TB) surgically assisted rapid maxillary expansion (SARME) on the width of the nasal soft and hard tissue.Patients and methodsTwenty skeletally mature patients (nine males and 11 females; mean age 19.4 years) with transverse maxillary hypoplasia were randomly assigned to hybrid or TB devices. The patients had undergone SARME operations, performed by the same surgical team using the same procedure (Le Fort I osteotomy with pterygomaxillary dysjunction, midline osteotomy, and no down-fracture). Nasal soft- and hard-tissue changes were analyzed using CBCT preoperatively (T0), at the end of the active expansion phase (T1), and after 6 months of retention (T2). The study was approved by the relevant ethics committee.ResultsThe skeletal and soft-tissue nasal parameters increased significantly in the T0–T1 and T0–T2 periods in both groups (P < 0.05). No statistically significant differences between the groups were observed. The mean piriform aperture width increased from 1.26 mm in T0–T1 to 0.97 mm in T1–T2 and 2.17 mm in T0–T2 (P < 0.008). In the soft tissue, the alar base width increased to 2.78 mm and the alar width to 2.95 mm in T0–T2 (P = 0.001). There was a positive correlation (63.6%) between the changes in skeletal and soft-tissue values.ConclusionThe hybrid and TB devices led to similarly significant widening effects in nasal soft and hard tissues in both the short term and 6 months after SARME.     

Three-dimensional prospective evaluation of tooth-borne and bone-borne surgically assisted rapid maxillary expansion

AimTo three-dimensionally (3D) assess the long-term effects of tooth-borne and bone-borne surgically assisted rapid maxillary expansion (SARME).Subjects and methodsThis prospective cohort study comprised 45 consecutive skeletally mature non-syndromic patients with transverse maxillary hypoplasia. In 28 patients, a tooth-borne distractor (Hyrax) was used for expansion, whereas in the remaining 17 a bone-borne distractor (transpalatal distractor, TPD) was used. Cone beam computed tomography (CBCT) scans were performed before treatment (T0) and 22 months later, after fixed appliance treatment (T1). 3D models were constructed from CBCT data and superimposed using voxel-based matching. Distance maps between the superimposed models were computed to evaluate the amount of skeletal changes.ResultsThe distance maps of the superimposed models showed positive distances on the right and left posterior alveolar segments of the maxilla indicating lateral expansion. The anterior maxillary region showed negative distances or posterior displacement and remodelling of the anterior alveolar region. There was no statistically significant difference between TPD and Hyrax for the three alveolar segments (p values ranged 0.63–0.81).ConclusionBone-borne and tooth-borne SARME were found to produce comparable results at the end of fixed appliance treatment regarding skeletal changes.     

Hyrax application as a tooth-borne distractor for maxillary advancement

Distraction osteogenesis (DO) has become a mainstream surgical technique for patients with jaw deformities. The aim of this study was to report the use of internal DO in the treatment of maxillary hypoplasia in a patient with cleft lip and palate. The case illustrates a 17-year-old boy with class III malocclusion, maxillary deficiency, and cleft lip and palate. Because the patient was experiencing severe hypernasality, it was decided to treat him by DO. The treatment process began by mounting a hyrax in the upper jaw for lateral expansion. A second hyrax was mounted in a way to create anteroposterior expansion. One day after the second hyrax application, the patient underwent a modified Le Fort I osteotomy. He was instructed to turn the screws twice per day for 12 days. The treatment was continued by means of a conventional face mask for 2 months. After 16 months of active treatment, favorable correction of the skeletal problem was observed. The S-N-A angle increased by 5 degrees, and patient's hypernasality was comprehensively improved.     

自制牙支持式牵张器治疗上颌骨畸形

目的:探讨运用自制牙支持式牵张器治疗上颌骨畸形.方法:利用自制牙支持式牵张器进行上颌骨牵张,治疗唇腭裂术后继发上颌发育不足、重度上颌后缩畸形、上颌骨获得性畸形等,共28 例.结果:除2 例因牵张器松动致牵张失败需重新手术外,余者术创正常愈合,牵张过程顺利,达到预期牵张目的.结论:牙支持式牵张器可有效的治疗上颌骨发育不足及软组织量不足的患者.     

上颌窦内壁分隔的 CBCT 观测

目的：通过CBCT观测上颌窦内壁间隔的解剖特点及分布规律。方法：调取苏州口腔医院放射科接受CBCT扫描的汉族患者的CT图像资料360例。 Mimics 17．0软件对上颌窦进行三维重建。对上颌窦间隔的发生率、数目、形态、位置及双侧分布状况进行观测。结果：360例中,上颌窦间隔的人群总发生率为37．8％,双侧发生占34．6％,双侧相关系数tau值为0．357（P＜0.01）。分布位置常位于磨牙区。不同性别组、年龄组、牙列缺失缺损及牙列完整组间发生率的差异无统计学意义（P＞0．05）。结论：上颌窦间隔在汉族人具有较高的发生率,了解其解剖特点及分布规律具有重要的临床意义。     

Quantitative analyses of maxillary sinus using computed tomography

The aim of this study was to evaluate the precision and accuracy of linear measurements of maxillary sinus made in tomographic films, by comparing with 3D reconstructed images. Linear measurements of both maxillary sinus in computed tomography CT of 17 patients, with or without lesion by two calibrated examiners independently, on two occasions, with a single manual caliper. A third examiner has done the same measurements electronically in 3D-CT reconstruction. The statistical analysis was performed using ANOVA (analyses of variance). Intra-observer percentage error was little in both cases, with and without lesion; it ranged from 1.14% to 1.82%. The inter-observer error was a little higher reaching a 2.08% value. The accuracy presented a higher value. The perceptual accuracy error was higher in samples, which had lesion compared to that which had not. CT had provided adequate precision and accuracy for maxillary sinus analyses. The precision in cases with lesion was considered inferior when compared to that without lesion, but it can't affect the method efficacy.     

Relationship between maxillary canine intra-alveolar position and maxillary incisor angulation: a cone beam computed tomography study

The aims of the present study were to evaluate the angulation and inclination of permanent maxillary incisors and to correlate the results to the intra-alveolar permanent maxillary canine position during mixed dentition, using cone beam computed tomography (CBCT). The subjects were 30 children aged 7 to 10 years in the inter-transitory period of mixed dentition (permanent incisors and first molars erupted; primary canines, first and second molars erupted; and permanent canines intraosseous). The CBCT scans were obtained and, using the Dolphin Imaging(?) software - version 11.0, 3D images were reconstructed and the measurements were performed. The angulation of the right and left lateral and central maxillary incisors was measured in relation to the sagittal plane and their inclination was measured in relation to the coronal plane. The intra-alveolar height of the right and left maxillary canines was measured from the cusp tip to the axial plane. Pearson's correlation at 5% significance level showed positive correlation between the canine height and the lateral incisor angulation. It was concluded that the intra-alveolar position of the maxillary canines has a direct influence on the angulation of maxillary incisors, especially the lateral incisors.