Evaluation of the relationship between sphenoid sinus morphology and area and volume by computed tomography.

OBJECTIVES: The aim of this study is to investigate the effect of sphenoid sinus pneumatization types, Onodi cell (OC), internal carotid artery (ICA), optic nerve (ON) on sinus volume and area on computed tomography (CT) images. METHODS: The CT images of 150 patients were evaluated. Sphenoid sinus pneumatization types, OC prevalence, protrusion and dehiscence of ICA and ON, the volume and area were evaluated. RESULTS: The sinus volume and area were statistically higher in patients with bilateral protrusion of ICA and ON then patients without protrusion of ICA and ON. The mean volume and area of sinus were 9949.4 ± 351.0 mm3 and 4570.9 ± 1604.9 mm2, respectively. The volume and area of sphenoid sinus did not differ significantly between groups with and without OC. The postsellar b type sphenoid sinus had the highest volume, while conchal type has the least volume. CONCLUSIONS: Bilateral protrusion and dehiscence of ICA and bilateral protrusion of ON caused a significant increase in the sphenoid sinus volume and area. The presence of ICA and ON, the pneumatization of the sinus is an anatomical structure that can affect the sinus volume and area. Before the operation, three-dimensional evaluation should be performed to determine whether these structures are bilateral/unilateral and it should be remembered that the sinus volume and area can change.

Multiple Regression Modeling for Age Estimation by Assessment and Comparison of Spheno-Occipital Synchondrosis Fusion and Cervical Vertebral Maturation Stages.

Objectives The aim of this study was (1) to evaluate the relationship between spheno-occipital synchondrosis (SOS) fusion stages, cervical vertebral maturation (CVM) stages, and clivus sizes with chronological age on cone-beam computed tomography (CBCT) images, and (2) to compare these methods for accurate age estimation using regression analysis. Methods The CBCT images of 200 individuals (102 females and 98 males) were included in the study. The SOS fusion stages and CVM stages were evaluated. The width and length of the clivus were measured. The effects of SOS fusion stages, CVM stages, clivus width, and clivus length on age estimation were evaluated by univariate tests and the effects of coexistence with ANCOVA and regression model. Spearman rank correlation analysis was also used to investigate the relationship between the SOS fusion stage, CVM stage, clivus width, and clivus length. Results The SOS stages, CVM stages, and clivus width were not shown statistically significant differences between the sexes ( p -values = 0.205, 0.162, and 0.277, respectively), whereas clivus length was significantly longer in males (42.9 ± 4.26 mm) than in females (41.04 ± 3.74 mm). Multiple regression analysis showed 80% success when all parameters (SOS fusion stages, CVM stages, clivus width, and clivus length) were taken into consideration. Conclusion In conclusion, with the use of CVM stages and SOS fusion stages together, an accurate and reliable age estimation can be obtained in forensic medicine.

Evaluation of the visibility of peri-implant bone defects using ultrasonography with two types of probes.

Background: The aim of the present study was to evaluate the efficacy of intraoral and extraoral ultrasonography evaluations performed with two different types of probes (linear and "hockey stick") for the visibility of peri-implant bone defects. Material and methods: Fourteen implants were inserted into sheep heads. Peri-implant bone defects were created without knowing the depth, which served as the gold standard for the defects. The defects were scanned with two different probe types (linear and hockey stick probes) extraorally and intraorally, using two different ultrasonography systems. For intra- and interobserver agreements for each probe types, Kappa coefficients were calculated. Results: The lowest ICC values were found in both intra- (ICC = 0.696) and interobserver reliability (ICC = 0.762) obtained with the extraorally used linear probe. There was a high agreement with the gold standard when using hockey sticky probes intraorally. For both linear probes, there were no significant differences in agreement among the two observers and the gold standard (p >0.05). Conclusions: High agreement was found when using high-frequency hockey stick probes intraorally, which means that they can be used with good effect for the evaluation of the visibility of peri-implant bone defects. To the best of our knowledge, this study is the first one on this subject. Thus, it can be stated that US can be an alternative method of examining defects. However, further studies are needed to evaluate the effectiveness of US in visualizing peri-implant bone defects.

Observation of the Pulp Chamber of Maxillary First Premolars: A Micro-computed Tomographic Study.

BACKGROUND: There are a few studies about the evaluation of maxillary first premolars internal structure with micro-computed tomography (micro-CT). The aim of this study was to assess morphological features of the pulp chamber in maxillary first premolar teeth using micro- CT. METHODS: Extracted 15 maxillary first premolar teeth were selected from the patients who were in different age groups. The distance between the pulp orifices, the diameter of the pulp and the width of the pulp chamber floor were measured on the micro-CT images with the slice thickness of 13.6 µm. The number of root canal orifices and the presence of isthmus were evaluated. RESULTS: The mean diameter of orifices was 0.73 mm on the buccal side while it was 0.61 mm on palatinal side. The mean distance between pulp orifices was 2.84 mm. The mean angle between pulp orifices was -21.53°. The mean height of pulp orifices on the buccal side was 4.32 mm while the mean height of pulp orifices on the palatinal side was 3.56 mm. The most observed shape of root canal orifices was flattened ribbon. No isthmus was found in specimens. CONCLUSION: Minor anatomical structures can be evaluated in more detail with micro-CT. The observation of the pulp cavity was analyzed using micro-CT.