Analysing the informative content of the upper jaw pathology visual examination

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Introduction

Multispiral computed tomography (MSCT) is considered by domestic and foreign authors to be the gold standard for diagnosing the pathology of connective tissue structures in the human body, including the maxillofacial region [1; 2]. The interface and software of MSCT-apparatuses produced by different manufacturers differ enormously in terms of quantity and quality, from the possibility of elementary ‘drawing’ of silhouettes to the detailed metric elaboration of objects with their interpretation, differentiation by density in Hounsfield units, step-by-step analysis of native slices and 3D reconstruction [3]. In experts' opinion, each programme has advantages and disadvantages, inaccuracies that require considering, which is possible with sufficient practice and academic knowledge [4]. The high resolution performance of most MSCT devices does not provide a detailed analysis of teeth root anatomy, including the maxilla, and tissues adjacent to the sinus floor. The developers, after numerous recommendations and requests of dental surgeons and maxillofacial surgeons, took into account the anatomo-topographical peculiarities of the upper jaw and directed their efforts to the design of cone-beam computed tomography (CBCT), which has a number of advantages. The software and other design solutions are developed to work with the finest facial bone structures possible. They also provide the most detailed view of the alveolar process and its covering mucosa, tooth roots, bone defects and the internal lining of the sinus cavity [5]. Each method of additional examination has certain advantages and disadvantages: thus, the main advantage of CBCT is the possibility to construct and view 3 reformatted images with structural volume elements (voxels) of a specified size, which, depending on the apparatus, vary from 1.125 to 0.3 mm per examination step. The smaller the step, the higher the visual informativeness of the study, which is necessary for differentiating pathological processes in the tiniest structures of the maxilla [6]. The results of modern examinations demonstrate the high accuracy of any CT scanner in the evaluation of complex structures of the maxillary sinus (MS) in imaging terms compared to X-ray examination in any view. The latter method (due to the huge number of overlapping anatomical structures) requires, even in a normal case, that the specialist has a high enough qualification with a mandatory course of classes in the ‘dissecting room’ with sawing of the skeletonised skull. This approach is time consuming, resource intensive, and, given the variability of pathology and the diversity of the human body structure, becomes less popular. Furthermore, this was confirmed by the results of the study of A.A. Ivanov (2010), obtained after determining the mean relative error of the measured (MRE) maxillary sinus volume. It did not exceed 0.6 ± 0.1 mm³ at the limit of agreement of indicators (LOI) – 1.2 ± 0.2 mm³ [7]. In the work of S.S. Petrova (2011), it was found that the mean relative error (MRE) volume in sinus length measurement was 0.5 ± 0.2 mm, and the value limit of agreement was 1.0 ± 0.3 mm [8]. Based on the results obtained, researchers highlight the unique evolutionarily determined features of sinus transformation that favourably influenced the adaptation mechanisms of the entire maxillofacial area [9]. In practical terms, the volume, height, the ratio of the tooth roots to the lower sinus wall, the degree of pneumatisation as well as the bone type and the state of the mucous membrane are of particular importance in the placement of dental implants. The volume of the maxillary sinus can vary from 2 to 18 mm³ depending on the sex, age, and racial characteristics of the individual [10; 11]. Analysis of anthropometric features of the maxillary sinus allows the specialist to determine the degree of pneumatisation, the ratio of the tooth root apexes to the floor of the nasal cavity, left and right sinuses, which is necessary in planning operations for immediate implantation, increasing the volume of bone tissue. Our study is aimed at finding the most informative method of imaging diagnostics.

Materials and methods

We analysed 96 CDs of patients with CBCT data and multispiral computed tomography of the upper jaw from the archives of the State Budgetary Institution of the Stavropol Krai “Pyatigorsk city clinic“, Republic Clinic named after Vishnevsky, Makhachkala, State Budgetary Institution of Stavropol Krai ”Stavropol Krai clinic”, Stavropol, Urgent care hospital No. 1, Rostov-on-Don, from 2010 to 2024. Patients who underwent two examination method, multispiral computed tomography and CBCT when radiographs were available, were included in the study. The main reason for performing two diagnostic methods was the insufficient informative value of one of them. MSCT of 48 patients was performed on Toshiba Aquilion CXL 128 with analisys in Radiant 3.0 software, 2023, the examination was prescribed for one or another reason by specialists of non-dental profile. Radiologists recommended patients to consult a dentist or maxillofacial surgeon after occasional ‘findings’. The deficit of information on MSCT data was the reason for performing 48 CBCT examinations. CBCTs were performed on Planmeca ProMax 3DClassic with subsequent analysis by Planmeca Romexis Viewer Win software. The volume of the maxillary sinuses was measured detailing the height, depth and width of the sinuses, which provided specific details of the pneumatisation and symmetry of the sinuses. The adjacent connective tissue structures were compared by determining the height and thickness of bone in the projection of the missing teeth using a virtual ruler with the determination of the length of the tooth roots and the distances from the anatomical root apex to the floor of the maxillary sinus.

Statistical analysis of data was performed using Statistica software package, version 10.0 (StatSoft, Inc.). Quantitative data are expressed as M ± σ, where M is the average value, σ is the standard deviation. Comparison of quantitative values between the groups was made by Student's criterion. All differences were considered significant at p < 0.05.

Results and discussion

The volume of the maxillary sinus averaged 7.94 ± 0.33 cm³. According to CBCT data, the location of the root apexes of teeth 14, 15, 16, 17, 24, 25, 26, 27 relative to the sinus floor is quite variable. The root apexes of tooth 1.4 in 66 % (32 patients) had an average distance of 2.16 ± 0.17 mm to the maxillary sinus floor according to multispiral computed tomography. According to CBCT in the same group of patients, the average distance was 1.81 ± 0.26 mm.

The root tips of teeth 15, 16, 17, 25, 26, 27 in 38 % (18 patients) had the evidence of apex location in the maxillary sinus according to CBCT. The same patients, according to MSCT data, detailed examination of the ratio of tooth root apexes, their permeability and obturation was difficult due to multiple artefacts that could not be analyzed by Radiant software interface, metric measurements had a low confidence level due to multiple overlapping structures and impossibility to change the examination step in the software.

Signs of pneumatisation reduction of various degrees were detected in 83.64 % of the examined patients. Verification of signs of reduction according to MSCT data consisted in determination of content density in the maxillary sinus cavity in 35.2 % of 20 Hounsfield units, which indicated the presence of exudate (transudate) in 64.8 % from 40 to 50 Hounsfield units, which was considered as neoplastic process.

In 11.71 % – hyperpneumatisation, the thickness of the bone plate separating the maxillary sinus from the maxilla did not exceed 3.2 ± 1.8 mm in 40 % patients, in 60 % the thickness reached 5.62 ± 3.4 mm, with multiple crypts protruding into the maxillary sinus.

4.65 % patients had moderate pneumatisation, no pathology was found in the maxillary sinus.

The comparative analysis pays attention to the condition of the mucous membrane, especially in patients with cavities, crypts, other defects and deformations of bony structures, the causes of which could not be determined. Differential diagnosis of anatomical features and pathologies of connective tissue structures of the maxilla and adjacent structures requires comprehensive analysis. MSCT with a 64-slice step is almost impossible to determine the configuration of crypts, cavities, spiky deformities. Thin structures not exceeding 1.5 mm in diameter are imaged as foci of hypopneumatisation, which can be mistakenly considered as a soft tissue or fluid component; in addition, multiple artefacts also make it difficult to aim the diagnosis. Radiographic images in any projection also do not provide reliable visualisation of the smallest details of the anatomical features of the maxilla due to overlapping structures. The accuracy, sensitivity, and specificity of X-ray examinations were evaluated subjectively based on visual parameters and objectively based on the results of surgical intervention [12].

Medical case 1

Patient E. MSCT was carried out in the preoperative stage. Based on the results of the study, the following conclusion was obtained: CT picture of maxillary sinus neoplasm on the left side against the background of hyperostosis of its walls, deformation of the lower wall of the orbital cavity, thickening of the mucous cells of the lattice bone (Fig. 1). The radiologists' reading of the data suggested aggressive surgery with wide surgical access to the inferior wall of the orbit and creation of a bony window more than 1 cm in diameter.

 

Fig. 1. Patient E., preoperative MSCT, maxillary sinus – left side view

 

According to CBCT data, the following interface was obtained: diffuse decrease in pneumatisation of the maxillary sinus on the left side, foreign body (most likely, filling material) in the distal third of the maxillary sinus floor on the left side, cystogranulomas in the projection of the root tips of teeth 2.5 and 2.7, the integrity of the lower wall of the orbit was not disturbed, no bone- dystrophy was visualized (Fig. 2).

 

Fig. 2. Patient E., preoperative CBCT, maxillary sinus – left side view

 

Following the examinations, the tactics of surgical intervention (classical maxillomotomy and cystectomy in the projection of the root apexes of teeth 2.5 and 2.7) was proposed taking into account the diagnosis: chronic odontogenic maxillary sinusitis on the left side. With the patient's consent, surgical intervention was performed with subsequent histological examination of the obtained materials (filling material in the maxillary sinus cavity, signs of chronic maxillary sinusitis in the exacerbation stage).

Imaging of the bony structures of the middle third of the face based on MSCT data was inaccurate due to the background response to the presence of foreign bodies in the oral cavity (orthopaedic structures), which raised a number of concerns about the state of connective tissue structures (Fig. 3).

 

Fig. 3. Patient E., preoperative MSCT, maxillary sinus – left side view

 

The CBCT data provided detailed information on the dental and maxillofacial system features, particularly the tooth roots, which were the cause of the pathological process in the maxillary sinus (Fig. 4).

 

Fig. 4. Patient E., preoperative CBCT, maxillary sinus – left side view

 

CBCT reformatting functions enabled maximum number of cross-sections of the maxillary sinus and surrounding structures to be imaged for differential diagnosis and subsequent success of surgical intervention (Fig. 5).

 

Fig. 5. Patient E., preoperative CBCT, maxillary sinus – left side view

 

Medical case 2

Patient С. MSCT was carried out in the preoperative stage. The examination results led to the following conclusion: areas of fibrous osteodysplasia of the left maxillary sinus, the left maxillary sinus is hypoplastic, deformed, there is a bony bridge in the anterior sinus, a small volume of fluid in the maxillary sinus cavity, irregular hypertrophy of the mucosa, maxillary ostium is not defined (Fig. 6). Otorhinolaryngologists evaluated the data as an aggressive surgical intervention with wide surgical access involving the bony structures of the maxilla.

 

Fig. 6. Patient C., preoperative CBCT, maxillary sinus – left side view

 

CBCT data revealed: absence of dystrophic changes in connective tissue structures, the left maxillary sinus is hypoplastic, deformed, there is a bony bridge in the anterior sinus, a neoplasm, most likely a true cyst of the maxillary sinus with a diameter of 13.46 mm, maxillary ostium is not detected in the distal third of the maxillary sinus floor (Fig. 7).

 

Fig. 7. Patient C., preoperative CBCT, maxillary sinus – left side view

 

After CBCT, the patient was diagnosed as having exacerbation of chronic maxillary sinusitis on the left side and maxillary sinus cyst on the left side. The patient underwent minimally invasive drainage of the maxillary sinus with cystectomy and formation of maxillary-nasal ostium under local anaesthesia.

Conclusions

When diagnosing the pathology of the dentoalveolar system, CBCT is recognised as an advantage compared to MSCT. CBCT software enables detailed examination of anatomical structures, their integrity, visualisation of foreign bodies (inlays, filling material) in the cavity of the crown and root parts of the tooth, as well as the ability to differentiate the integrity and defects of hard tissues, to determine the etiology and pathogenesis of the process with maximum accuracy, analyzing their micro dimensions step by step. In case of disputable cases, re-examination using higher resolution and more advanced programmes provided with CBCT equipment allowed to avoid unnecessary surgical interventions or to reduce their scope, thereby improving the quality of life in the postoperative period.

About the authors

A. M. Idrisova

Dagestan State Medical University

Email: sshakbanov789@mail.ru
ORCID iD: 0009-0007-2734-0725

Lecturer of the Department of Dental Surgery and Maxillofacial Surgery

Russian Federation, Makhachkala

Kh. M. Magomedova

Dagestan State Medical University

Author for correspondence.
Email: sshakbanov789@mail.ru
ORCID iD: 0000-0001-8744-2976

Lecturer of the Department of Dental Surgery and Maxillofacial Surgery

Russian Federation, Makhachkala

A. K. Shakhbanov

Dagestan State Medical University

Email: sshakbanov789@mail.ru
ORCID iD: 0009-0006-6637-3223

Head of the Department of Maxillofacial Surgery

Russian Federation, Makhachkala

Kh. A. Ordashev

Dagestan State Medical University

Email: sshakbanov789@mail.ru
ORCID iD: 0000-0002-4290-2665

PhD (Medicine), Head of the Department of Dental Surgery and Maxillofacial Surgery

Russian Federation, Makhachkala

S. A. Shakhbanov

Dagestan State Medical University

Email: sshakbanov789@mail.ru
ORCID iD: 0009-0001-3313-3729

Maxillofacial Surgeon

Russian Federation, Makhachkala

K. S. Gandylyan

Stavropol State Medical University

Email: sshakbanov789@mail.ru
ORCID iD: 0000-0001-8682-6986

PhD (Medicine), Associate Professor, Head of the Department of Dental Surgery and Maxillofacial Surgery

Russian Federation, Stavropol

I. A. Shakhbanov

Dagestan State Medical University

Email: sshakbanov789@mail.ru
ORCID iD: 0009-0008-3483-0287

Lecturer of the Department of Dental Surgery and Maxillofacial Surgery

Russian Federation, Makhachkala

O. N. Belousova

Belgorod National Research Yniversity

Email: sshakbanov789@mail.ru

DSc (Medicine), Associate Professor, Professor of the Department of Hospital Therapy, Endocrinologist

Russian Federation, Belgorod

A. A. Sletov

Belgorod National Research Yniversity

Email: sshakbanov789@mail.ru
ORCID iD: 0000-0001-5183-9330

DSc (Medicine), Professor of the Department of General Dentistry

Russian Federation, Belgorod

References

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