3D-CT imaging processing for qualitative and quantitative analysis of maxillofacial cysts and tumors

Deep learning in the diagnosis for cystic lesions of the jaws: a review of recent progress

Cystic lesions of the gnathic bones present challenges in differential diagnosis. In recent years, artificial intelligence (AI) represented by deep learning (DL) has rapidly developed and emerged in the field of dental and maxillofacial radiology (DMFR). Dental radiography provides a rich resource for the study of diagnostic analysis methods for cystic lesions of the jaws and has attracted many researchers. The aim of the current study was to investigate the diagnostic performance of DL for cystic lesions of the jaws. Online searches were done on Google Scholar, PubMed, and IEEE Xplore databases, up to September 2023, with subsequent manual screening for confirmation. The initial search yielded 1862 titles, and 44 studies were ultimately included. All studies used DL methods or tools for the identification of a variable number of maxillofacial cysts. The performance of algorithms with different models varies. Although most of the reviewed studies demonstrated that DL methods have better discriminative performance than clinicians, further development is still needed before routine clinical implementation due to several challenges and limitations such as lack of model interpretability, multicentre data validation, etc. Considering the current limitations and challenges, future studies for the differential diagnosis of cystic lesions of the jaws should follow actual clinical diagnostic scenarios to coordinate study design and enhance the impact of AI in the diagnosis of oral and maxillofacial diseases.

Study Between Panoramic Radiography and Cone Beam-Computed Tomography in the Diagnosis of Ameloblastoma, Odontogenic Keratocyst, and Dentigerous Cyst

OBJECTIVE

To determine how the diagnosis may or may not be influenced by cone-beam computed tomography (CBCT), comparing the diagnostic hypotheses obtained using images of panoramic radiographs and CBCT in cases of ameloblastoma, odontogenic keratocyst, and dentigerous cyst.

STUDY DESIGN

Five cases were selected for each lesion. Panoramic radiographs and CBCT scans were analyzed by 15 dentists for the formulation of the diagnostic hypotheses. Two observers performed the analyses and measurement of qualitative and quantitative features of the lesions evaluated in the CBCT.

RESULTS

There was no statistically significant difference in correct diagnostic average between panoramic radiography and CBCT, but there was a significant difference in correct diagnostic average in the diagnosis of ameloblastoma using CBCT compared to panoramic radiography. Master's and PhD-level observers had greater correct diagnostic average in the diagnosis of odontogenic keratocyst using panoramic radiograph compared to specialists, with a significant difference.

CONCLUSION

Cone-beam computed tomography images revealed that the ameloblastomas were greater in size and expansion compared to the odontogenic keratocyst and the dentigerous cysts. Ameloblastomas showed a higher incidence of multiloculated aspects compared to odontogenic keratocyst and dentigerous cysts. There were no differences between quantitative and qualitative features of odontogenic keratocyst and dentigerous cysts.

CBCT Evaluation of the Vital Mandibular Interforaminal Anatomical Structures

BACKGROUND

Oral implants are considered safe in the mandibular anterior region, but complications often occur if vital structures such as inferior alveolar nerve, mandibular incisive canal (MIC), anterior mental loop (AL), or mental foramen (MF) are not properly identified.

AIM

The aim was to evaluate vital anatomical structures in the mandibular interforaminal region and to investigate sexual dimorphism and differences with respect to left and right side regions using cone-beam computed tomography (CBCT).

MATERIALS AND METHODS

Eighty CBCT scans (forty male and forty female) were analyzed for MF position and shape, presence and measurement of AL and MIC (both in mm), emergence patterns of mandibular canal, and symmetry of MF and AL. A pilot study was conducted on five patients to determine interobserver reliability among two oral and maxillofacial radiologists, considered for interpretation of CBCT images. All the scans were taken by CS 9300, CBCT machine adjusted at 80 kVp, 15 mA, voxel size 0.3 × 0.3 × 0.3, and field of view of 10 × 5 (mandible only). The acquired images were reconstructed into multiplanar views (axial, panoramic, and cross-sectional) for evaluation.

RESULTS

The mean age of the study population was 42.64 ± 16.22 years, with males noted with slightly higher age. Position 4 of MF (below the apex of the second premolar) was noted the most on the right side, whereas position 3 (between the first and second premolars) was noted on the left side, with 75% of symmetrical MF position. The oval-shaped MF was most common among both genders and sides. The prevalence of MIC was noted in 93.75% of patients with a mean length of 12.09 ± 5.95 mm. The prevalence of AL was 53.13%, with a mean length of 1.07 ± 1.42 mm. No statistically significant sexual dimorphism (P > 0.05) was found between genders or sides for all the evaluated interforaminal parameters.

CONCLUSION

CBCT evaluation of vital anatomical structures needs to be elicited before planning an interforaminal placement of implants, and no sexual dimorphism was found regarding them.

Evaluation of mandibular odontogenic keratocyst and ameloblastoma by panoramic radiograph and computed tomography

OBJECTIVES:

The purpose of this study was to describe and compare the main imagenological features of mandibular ameloblastomas and odontogenic keratocyst (OKC) using panoramic radiograph (PR) and CT.

METHODS:

The sample consisted of nine cases of ameloblastomas and nine cases of OKC. PR and CT images were analyzed according to shape, internal structure, borders, associated unerupted tooth, root resorption, expansion and perforation of cortical bones.

RESULTS:

PR evaluation allowed the identification of the lesion's location, presence of sclerosis in the periphery, presence of associated non-erupted tooth and expansion of the mandible's lower border cortical bone. CT was more accurate than PR in the assessment of the lesion shape, presence of inner bone septa, root resorption, buccolingual expansion and rupture of cortical bone. Most cases of ameloblastoma and OKC presented buccolingual expansion and erosion of cortical bone. Only ameloblastomas showed tooth root resorption.

CONCLUSIONS:

Although PR is very helpful and widely used, CT provides more precise information on buccolingual expansion, calcification, bone septa, perforation of cortical bones and tooth resorption, features that are frequently underdescribed in the literature, particularly in OKC.

Advances in assessing the volume of odontogenic cysts and tumors in the mandible: a retrospective clinical trial

PURPOSE

To compare two methods of creating three-dimensional representations of mandibular cysts and tumors on the basis of computed tomography (CT) and cone beam computed tomography (CBCT) data.

METHODS

A total of 71 patients with acquired jaw cysts took part in this retrospective clinical study. CT and CBCT scans were obtained from all patients and saved in the Digital Imaging and Communications in Medicine (DICOM) format. Data were analyzed twice with iPlan software. Analysis was performed manually and using an interpolarization algorithm. The accuracy of the two methods in assessing cyst volume was compared.

RESULTS

Manual delineation did not provide more accurate results than the interpolarization algorithm.

CONCLUSION

There are no major differences between manual analysis and analysis using the interpolarization algorithm. The use of the algorithm, however, has the advantage of rapidity.

Application of cone beam computed tomography in oral and maxillofacial surgery

In the past decade, the utility of cone beam computed tomography (CBCT) images in oral and maxillofacial surgery has seen continuous increase. However, CBCT images are not always able to replace other imaging modalities. Based on the current published knowledge, this paper discusses advantages and limitations of CBCT images in the diagnosis and surgical planning of dentoalveolar procedures, odontogenic cysts, benign and malignant tumours, inflammatory changes, orthognathic surgery, maxillofacial trauma, sinus disorders, and systemic and osseous conditions that manifest in the maxillofacial area. This paper also suggests alternative imaging modalities when CBCT images are not adequate for surgical planning.

Healing of bone defects by an osteopromotion technique using solvent-dehydrated cortical bone plate: a clinical and radiological study

Osseous defects of the jaws following trauma, cysts, infection or congenital deformity may show poor osteogenesis and the affected area may never be completely filled with bone. It is widely accepted in guided tissue regeneration that physically halting soft connective tissue proliferation into bone allows bone regeneration. This concept is called the "osteopromotion principle." The purpose of the present study was to evaluate the effect of solvent-dehydrated cortical bone plates as a barrier to allow bone regeneration by assessing the osteopromotion principle. 30 patients (18 male, 12 female) with cystic lesions of the jaws were assigned to two different groups. The patients in Group A were treated by enucleation. In Group B, were treated by removal of the lesion and placing a solvent-dehydrated cortical bone plate on top of the cyst cavity to avoid ingrowth of connective tissue. Both groups were evaluated radiographically using spiral-computed tomography (CT) before surgery and 12 months postoperatively. In group B, all cystic cavities showed complete bone healing in 12 months. At the same period, invasion of the soft connective tissue were observed in the patients treated only by enuclation. This study demonstrates that solvent-dehydrated cortical bone plates can be used as a barrier in treatment of cyst cavities and they hinder ingrowth of connective tissues and promote successful bone healing.

Dentigerous cyst associated with a formocresol pulpotomized deciduous molar

This report presents a case of dentigerous cyst associated with a formocresol pulpotomized deciduous molar detected during routine examination. Dentigerous cyst is an epithelial-lined developmental cavity that encloses the crown of an unerupted tooth at the cementoenamel junction. The present case describes a 9-year-old girl sent to the dental clinic by her dentist, who had accidentally discovered in the panoramic radiograph a single, unilocular, well-defined, radiolucent area enclosing the second left unerupted mandibular premolar. The second left primary molar had been pulpotomized 2 years before and buccal swelling without redness occurred near the tooth, evidencing bone expansion. Surgical treatment was carried out, the tooth was extracted, and a cystectomy was performed under local anesthesia in the dental office. The histological study confirmed the suspected diagnosis of dentigerous cyst. The relation between pulpotomy and dentigerous cysts is discussed.

Clinical-embryological and radiological correlations of oculo-auriculo-vertebral spectrum using 3D-CT

OBJECTIVES

The purpose of this paper is to present a variety of imaging findings of oculo-auriculo-vertebral spectrum (Goldenhar syndrome) using three-dimensional reconstructed images from computed tomography (3D-CT), associating clinical and embryological patterns of the syndrome.

METHODS

The study population consisted of 10 patients with oculo-auriculo-vertebral spectrum with clinically identified hemifacial microsomia. The patients were examined using spiral CT, and abnormal imaging features were grouped under facial, ear and temporal bone, vertebral, and skull base anomalies. The original CT data were transferred to a networked computer workstation with a computer graphics system to generate 3D-CT volume rendered images of the skull and vertebra. Two observers analysed the bone and muscular setting protocols to assess the relationship between bone and muscular structures.

RESULTS

Asymmetric underdevelopment was a characteristic pattern of this syndrome resulting from hypoplasia of the mandibular ramus and condyle, the zygomatic, sphenoid and auricular conduct bones, and the temporal and masseter muscles. The syndrome was associated with local atrophy seen on 3D-CT images using specific bone and muscles protocols in all cases.

CONCLUSIONS

Understanding the aetiology, embryology and wide imaging spectrum of this syndrome is essential to make a correct diagnosis, for treatment planning, and for evaluation when associated with a 3D-CT computer graphics system.