Volumetric analysis of keratocystic odontogenic tumors and non-neoplastic jaw cysts - Comparison and its clinical relevance

Optimal time to definitive enucleation of large cysts following marsupialization: a single center, retrospective study

OBJECTIVES

Optimal time to enucleation following marsupialization of large odontogenic mandibular cysts is undefined. We aim to assess volume reduction throughout follow-up, to indicate optimal time to enucleation. Secondary objectives include the identification of factors influencing cyst reduction.

STUDY DESIGN

We retrospectively enrolled 15 patients with mandibular cysts of different histological types treated with marsupialization at our center between 2018-2022. Cyst volume was assessed with cone-beam computed tomography (CBCT) and a semi-automatic segmentation algorithm, at baseline and between 6-8 months post marsupialization.

RESULTS

The overall mean cyst volume reduction percent (VR%) was 57.7% or 0.2% per day. VR% at 8 months was significantly higher than those assessed at 6-7 months (67.1% vs 47.1%, p=0.003). Time to CBCT was the only independent variable influencing cyst VR%.

CONCLUSION

Our study proves that the optimal time to enucleation for mandibular cyst is 8 months, independent of histological cyst type, patient age, baseline cyst volume and the number of pre-operative residual bone walls.

Volumetric Assessment of Apical Periodontitis Using Cone-Beam Computed Tomography-A Systematic Review

This systematic review aimed to investigate the scientific literature on volumetric studies concerning the diagnosis and treatment of apical periodontitis using CBCT. A systematic review protocol was written following the preferred reporting items for the systematic reviews and meta-analyses (PRISMA) checklist. Four electronic databases were searched for relevant publications in English, which were published up to 21 January 2023. The inclusion criteria and corresponding search keys were applied. The risk of bias was assessed using the Joanna Briggs Institute Meta-Analysis of Statistic Assessment and Review Instrument. The search strategy identified 202 studies, with 123 studies excluded during the title and abstract screening and 47 studies left for full text screening. A total of 17 studies met the inclusion criteria. The lesion volume was measured and classified according to different indices which compared the effectiveness of their diagnostics. Moreover, the volume of AP lesions increased with the thickness of the maxillary sinus mucosa in primary and secondary infections and decreased due to endodontic treatment. Volumetric measurements using CBCT are useful in the correct definition of periapical tissue pathosis using a CBCT periapical volume index and assessment of the dynamics of the treatment of apical lesions.

A Volumetric and Morphological Analysis of Recurrent Odontogenic Keratocysts by Semiautomatic Segmentation

PURPOSE

The authors conducted this study to provide morphological and volumetric data of recurrent odontogenic keratocysts of the upper and lower jaw to emphasize risk factors in accordance with their radiological appearance and guide clinical decisions for jeopardized patients.

METHODS

By applying the open-source software "ITK-Snap" on cone-beam computed tomography images, volumetric measurements of histopathologically diagnosed recurrent odontogenic keratocysts could be performed. For statistical investigations, descriptive statistics and independent Student t test were performed. The intraclass correlation coefficient was used to assess intra- and inter-rater reliabilities. P values P < 0.05 were considered significant.

RESULTS

Forty patients (24 male and 16 female) were included in this study. Recurrent odontogenic keratocysts had a mean maximum diameter of 28.91 mm ± 12.00 mm and a mean volume of 4.48 cm3 ± 4.29 cm3. According to morphology, irregular shape (P = 0.001; P = 0.005), unclear margin (P = 0.001; P = 0.001), multilocular morphology (P = 0.001; P = 0.001), and cortical bone exceedance (P = 0.001; P = 0.007) are statistically significantly associated with a larger cyst diameter and volume. Furthermore, significant differences by diameter and volume could be shown between patients with and without iliac crest graft reconstruction (P = 0.001; P = 0.001).

CONCLUSIONS

Volumetric analysis reveals that recurrent odontogenic keratocysts show large diametric and volumetric extension that leads to complex reconstruction by iliac crest grafts, adding an argument that special attention should be paid to this entity and its recurrence. In case of difficult histopathological examination, lesions with irregular shape and margin, multilocular morphology, cortical bone exceedance, and clinically visible symptoms should be considered for close morphological and volumetric clinico-radiological follow-up.

Dynamic Maxillary Sinus Changes of Facial Vascularized Composite Allotransplants

SUMMARY

Skin is one of the target tissues of rejection in face transplants and, because of its easy accessibility, has become the gold standard in the diagnosis of rejection. The allograft contains deeper tissues where rejection can occur, but samples cannot be obtained because of difficult access. Deep tissue changes were monitored on computed tomographic scans of the midface in six face transplant recipients with the help of image segmentation. The maxillary sinus was identified as a dynamic anatomical compartment. Observed changes in volume of the aeration relative to the opacification (aeration coefficient) of the maxillary sinus were quantified with the help of image segmentation. Changes in the aeration coefficient as a surrogate of mucosal swelling were quantified and related to time, treatment, and skin rejection grade. Lower aeration coefficients were found only in patients with transplanted maxillary sinus mucosa. Pathologic changes were not observed in face transplant recipients with a native maxillary sinus. The data show that the aeration coefficient was significantly lower at the time of biopsy-proven allograft rejection. Neither mechanical, nor infectious, nor medication side effects sufficiently explain the findings presented herein. The authors' findings are important to consider for clinical management of face transplant patients who receive parts of the sinonasal tract. The authors identify a potential radiologic biomarker of deep tissue allograft rejection. In the future, the proposed methodology might prove useful in monitoring deeper dynamic tissue changes in vascularized composite allografts and might help in designing patient-specific, individualized treatment strategies.

Volumetric analysis of mucous retention cysts in the maxillary sinus: A retrospective study using cone-beam computed tomography

Purpose

The aim of this study was to evaluate the volumetric characteristics of mucous retention cysts (MRCs) in the maxillary sinus and to analyze potential associations of MRCs with dentoalveolar pathologies.

Materials and Methods

Cone-beam computed tomography (CBCT) scans exhibiting bilateral maxillary sinuses that were acquired from January 2016 to February 2019 were initially screened. A total of 227 scans (454 sinuses) that fulfilled the inclusion criteria were included. The presence, location, and volumetric characteristics of the diagnosed MRCs were evaluated on CBCT images using the 3D-Slicer software platform. The presence of MRCs was correlated with potential influencing factors including age, sex, and dentoalveolar pathology. For MRCs located on the sinus floor, factors with a potential impact on the volume, surface, and diameter were analyzed.

Results

An MRC was present in 130 (28.6%) of the 454 sinuses. Most MRCs were located on the sinus walls and floor. The mean MRC volume, surface, and diameter were 551.21±1368.04 mm³, 228.09±437.56 mm², and 9.63±5.40 mm, respectively. Significantly more sinuses with associated endodontically treated teeth/periapical lesions were diagnosed with an MRC located on the sinus floor. For MRCs located on the sinus floor, endodontic status exhibited a significant association with increased volume, surface, and diameter.

Conclusion

Periapical lesions might be a contributing factor associated with the presence and volume of MRCs located on the sinus floor. The 3D-Slicer software platform was found to be a useful tool for clinicians to analyze the size of MRCs before surgical interventions such as sinus floor elevation procedures.

Postoperative complications after bimaxillary orthognathic surgery: A retrospective study with focus on postoperative ventilation strategies and posterior airway space (PAS)

PURPOSE

The aim of this study was to evaluate the impact of extubation time on postoperative complications in patients undergoing bimaxillary orthognathic surgery. We therefore retrospectively compared the effect of early extubating (EE) in the operating room versus delayed extubating (LE) on the intensive care unit (ICU) regarding postoperative complications and length of ICU/hospital stay (LOICUS/LOHS). Furthermore, we analyzed the influence of the PAS change on postoperative complications.

METHODS

The clinical data of 117 patients were retrospective analyzed regarding postoperative complications using Clavian-Dindo Classification. Volumetric calculations of the pre- and postoperative PAS were conducted using ITK-SNAP software. The Fisher's exact test was performed to evaluate the significance of differences between categorical variables. Continuous variables were analyzed using the Mann-Whitney U-Test or the Kruskal-Wallis one-way analysis of variance. Regression analysis was used estimating predictors for postoperative complications.

RESULTS

EE led to significant shortening of LOICUS (p < 0.001) and LOHS (p = 0.023). In total, we recorded 38 complications (minor n = 30; major n = 8) within the hospital stay. Complication rates were without significant differences with respect to the postoperative ventilation strategy. Large changes in PAS volume led to an increase in the major complication rates (p = 0.031). Increase or decrease of PAS was independent from postoperative complication rates (p = 1.000). Higher body mass index (p = 0.04) and a higher ASA PS score (p = 0.016) were associated with increased major complication rates.

CONCLUSION

Early extubation after surgery is a safe procedure and is associated with a reduced LOICUS and LOHS. Complications seem to occur more frequently in marked changes of the PAS and should be considered in perioperative risk stratification.

The presentation of odontogenic keratocysts in the jaws with an emphasis on the tooth-bearing area: a systematic review and meta-analysis

PURPOSE

This study was conducted in order to gain insight in the actual ratio of odontogenic keratocysts occurring in the tooth-bearing area as compared to the posterior region of the jaws in order to come up with reliable data to base upon a rational treatment policy.

METHODS

We searched MEDLINE, Web of Science, Scopus, and Cochrane databases for studies reporting on the location of mandibular and maxillary odontogenic keratocysts. All records were independently assessed and a meta-analysis was performed. Risk difference with a confidence interval of 95% of having the lesion in the posterior region versus the tooth-bearing area was the effect measure. P value for the summary effect of < 0.05 was considered statistically significant.

RESULTS

The 2615 records retrieved were reduced to 34 studies to be qualitatively/quantitatively assessed. The pooled values showed that the difference in the clinical risk of having keratocysts in the posterior region of the mandible and in the tooth-bearing area of the maxilla is 21 and 43%, respectively (P < 0.02 and P < 0.00001).

CONCLUSIONS

A substantial amount of keratocysts occur in the tooth-bearing area of the jaws, requiring attention.

Image segmentation-based volume approximation-volume as a factor in the clinical management of osteolytic jaw lesions

OBJECTIVE

Size characterization of osteolytic jaw lesions (OJL), in particular of neoplastic nature, is heterogeneously performed and lacks standardization in the medical literature and clinical practice. An OJL's volume holds promise as a surrogate for treatment response and prognosis. We comparatively evaluate various methods for size characterization of odontogenic OJLs.

METHODS

We retrospectively performed semiautomatic image segmentation of CBCT data sets for volume approximation of neoplastic (51) and non-neoplastic odontogenic OJLs (100). We assessed the three greatest orthogonal diameters and calculated the volume using the cuboid- and ellipsoid-formula. Image segmentation was carried out using ITK-SNAP. Image segmentation-based volume approximation served as reference. Intra- and inter-rater variability were evaluated at hand of Bland-Altman-Analysis and dice similarity coefficient (DSC).

RESULTS

Concerning the intrarater variability, we found the DSC to be highest for image segmentation-based volume approximation, simultaneously showing the tightest limits of agreement and greatest reliability. The cuboid formula showed consistent overestimation of the lesion's volume with a percent mean difference of -52 % (upper and lower limits of agreement +8.57 %  and -112.63%, respectively). In mean, the ellipsoid formula underestimated the lesion's volume by 10.1% (upper and lower limits of agreement +76.8%  and -56.6%, respectively). Inter rater variability was higher for formula-based volume approximation. Volume and multilocularity (p = 0.001) correlate with aggressiveness and growth potential.

CONCLUSIONS

Segmentation-based volume approximation holds great promise for patient individualized treatment planning and clinical management. The data suggest that maximum tumour diameter-based size characterization, especially the cuboid-formula and the maximum diameter alone, should not be recommended.

FAMI Screws for Mandibulo-Maxillary fixation in mandibular fracture treatment - Clinico-radiological evaluation

Mandibulo-maxillary fixation (MMF) is indispensable for mandibular fracture treatment. Various means for MMF have been proposed, of which arch bars are widely considered to be the mainstay. However, disadvantages to this method have initiated a quest for an alternative, leading to the introduction of MMF screws. MMF screws have frequently been criticized for poor stability of fracture sites, root damage, hardware failure, and nerve damage. We retrospectively evaluate the FAMI (Fixation and Adaptation in Mandibular Injuries) screw in mandibular fracture treatment by scanning for clinically and radiologically visible complications. In total, 534 FAMI screws were used in the successful treatment of 96 males and 34 females. Condylar fractures were most commonly encountered, representing 120 of 241 fracture sites. 15 general fracture-related complications occurred, with the most common being nerve function impairment (3.8%) and postoperative malocclusion (4.6%). In nine cases (7%), clinically visible FAMI-screw-related complications occurred, with the most prevalent being screw loosening (2.3%) and mucosal signs of inflammation (3.1%). Duration of FAMI screws was associated with the occurrence of clinically visible complications (p = 0.042). Radiologically, clinically invisible dental hard tissue damage was noted in 21 individuals (16%). Therefore, FAMI screws seem to be a reliable and safe method for mandibulo-maxillary fixation.