Optimization of orofacial cleft imaging protocols using device-specific low-dose cone-beam computed tomography.

OBJECTIVE: The aim of this study was to present optimized device-specific low-dose cone-beam computed tomography (CBCT) protocols with sufficient image quality for pre-surgical diagnostics and three-dimensional (3D) modelling of cleft defects. METHODS: Six paediatric skulls were acquired, and an artificial bony cleft was created. A high-resolution CBCT scan acted as a reference standard (Accuitomo 170, Morita, Kyoto, Japan) for comparing eight low-dose protocols of Newtom VGi-evo (QR Verona, Cefla, Verona, Italy), which included Eco and Regular protocols with different field of views (FOVs). Delineation of lamina dura, cementoenamel junction (CEJ), trabecular bone and bony bridge were assessed. A 3D model of the defect was also evaluated. RESULT: The dose area product of low-dose protocols ranged from 31 to 254 mGy*cm2. Despite the dose difference of up to eight times between applied protocols, trabecular bone and CEJ exhibited appropriate image quality in all scans. However, Regular small FOV protocols (5 × 5 and 8 × 5 cm2), for both lamina dura and bony bridge, demonstrated a significant improvement in image quality compared to Eco FOV counterparts. Based on 3D defect analysis, no significant difference existed between low-dose protocols and the reference standard. CONCLUSION: The findings highlight the possibility of achieving a considerable reduction (up to eight times) in the radiation dose using low-dose CBCT protocols while maintaining sufficient image quality for assessing anatomical structures and 3D modelling in cleft cases.

Creation of Dimicleft radiological cleft phantom skulls using reversed virtual planning technique.

OBJECTIVES: The aim of this technical report was to develop customized pediatric phantoms for cone-beam computed tomography (CBCT)-related research in cleft patients. METHODS: Six human pediatric skulls (age: 5-10 years) were recruited. A cone-beam computed tomography (CBCT) scan was taken for each skull, followed by virtual modeling through the process of segmentation. An artificial cleft was designed and printed to be applied onto the skull for the creation of an artificial cleft. The skulls were covered with non-radiopaque tape and immersed in melted Mix-D soft tissue equivalent material. The resulting phantoms covered with Mix-D were assessed radiologically by two expert radiologists. These phantoms were referred to as Dimicleft pediatric skull phantoms. RESULTS: Dimicleft phantoms were able to appropriately mimic in vivo circumstances. No gaps existed between Mix-D and bony tissue. Virtual planning allowed the optimal designing of an artificial cleft onto the phantom. The artificially created cleft was suitable to determine the size, location, and extent of the cleft. CONCLUSIONS: Dimicleft phantoms could act as a viable alternative to other commercially available options for assessing image quality and optimizing CBCT protocols in cleft patients for diagnostics and three-dimensional treatment planning.

Moving toward patient specificity for devising cone-beam computed tomography field-of-views: A normative maxillary skeletal dimensional analysis.

BACKGROUND: A lack of evidence exists comprehensively assessing skeletal dimensions in a Caucasian population group at different ages. AIM: To provide age- and gender-specific normative skeletal dimensional measurements of the maxillary region using cone-beam computed tomography (CBCT) imaging. DESIGN: Cone-beam computed tomography images of Caucasian patients were acquired and divided into different age groups ranging from 8 to 20 years. Linear measurements were taken to evaluate seven distance-based variables, which included anterior nasal spine-posterior nasal spine (ANS-PNS) distance, bilateral maxillary first molar's central fossae (CF) distance, palatal vault depth (PVD), bilateral palatal cementoenamel junction (PCEJ) distance, bilateral vestibular CEJ (VCEJ) distance, bilateral jugulare distance (Jug) and arch length (AL). RESULTS: A total of 529 patients (243 male, 286 female) were selected. ANS-PNS and PVD showed the highest change in dimensions from 8 to 20 years of age. On the contrary, AL had the least variability in all age groups. Male patients had larger dimensions and showed a significant change in all dimensional measurements (p < .001) than female patients. CONCLUSION: The maxillary linear dimensions varied across different age groups. The presented maxillary normative data could serve as a reference guide for devising patient-specific CBCT field of views.

Evaluation of 3D visualization, planning and printing techniques in alveolar cleft repair, and their effect on patients' burden.

BACKGROUNDS: The aim of this study was to describe our auxiliary surgical techniques in alveolar cleft reconstruction and evaluate the patients burden after 3 years of surgical experience. METHODS: At the Cleft center, Semmelweis University Budapest, 28 patients underwent alveolar bone grafting between September 2017 and September 2020. We have used CBCT scans and computer software to perform 3D simulation of the alveolar defect and planning of patient- and defect specific grafts. An individual graft mold was designed for each alveolar defect and 3D printed for intra-operative use. During the surgical intervention, the mold was used to harvest the most appropriate amount and precise shape of graft material. We used cancellous iliac crest graft. After performing a descriptive statistical analysis of our patient group, we used a quality-of-life questionnaire to measure the patient's self-perception. RESULTS: In all cases the treatment sequence could be applied, planning and surgery was successful and uneventful. Patients did not experience more pain, bleeding or any feeding impairment. No inflammatory or wound healing reactions were observed. There were no major adverse effects causing permanent problems. CONCLUSIONS: Our follow-up and patient satisfaction questionnaire showed that our treatment sequence with auxiliary techniques brought no further burden to the patients care and hospitalization, even though it is more complex. Efficacy of this treatment method and improvement in graft integration has yet to be determined.