Evaluation of the relationship between tympanic plate morphology and degenerative bone changes of condyle and articular eminence

INTRODUCTION

This study aimed to evaluate the relationship between tympanic plate morphology and degeneration of temporomandibular joint (TMJ) condyle and articular eminence (AE).

MATERIAL AND METHODS

Cone beam computed tomography images of 700 patients (345 males, 355 females) were evaluated. The prevalence and location of tympanic plate pneumatization (TPP) and foramen tympanicum (FT) were recorded. Sagittal scans of the TMJs were classified according to the degenerative bone changes of condyle and AE (flattening, osteophytes, erosion, sclerosis, and subcortical cysts).

RESULTS

TPP was found in 106 of 700 patients (15.2%) while FT was found in 165 (23.2%) of the patients. TPP and FT were bilateral in 52 (49.1%) patients and 46 (27.9%) patients, respectively. The mean axial diameter of FT was 2.53mm and the mean sagittal diameter was 2.52mm. The most common degenerative changes for condyle and AE were flattening.

CONCLUSION

To know these structures is important for surgical operations in the region of TMJ and ear to prevent complications. CBCT is useful to evaluate these anatomical landmarks and the relationship between them and the degenerative bone changes of condyle and AE.

Evaluation of the effects of hemoglobinopathies on the mandible with fractal dimension analysis

Aims

The aim of this study was to evaluate the mandibular bone changes on panoramic radiographs of thalassemia and sickle cell anemia (SCA) patients using fractal dimension (FD) analysis and to compare the findings obtained from healthy individuals.

Materials and Methods

A total of 90 panoramic radiographs (from 30 patients with thalassemia, 30 patients with SCA and 30 healthy individuals) were assessed to measure FD, mandibular cortical width (MCW), panoramic mandibular index (PMI) in the mandible. Three region of interests (ROI) of angulus, corpus, and interdental bone were created. FD was calculated using ImageJ program.

Results

In thalassemia group, the mean value of FD was 1.11, 1.03, and 1.02 in interdental bone, corpus, and angulus, respectively. In SCA group, the mean value of FD was 1.10, 1.05, and 1 in interdental bone, corpus, and angulus, respectively. In control group, the mean value of FD was 1.09, 1.04, and 1 in interdental bone, corpus, and angulus, respectively. FD value of interdental bone are significantly higher in thalassemia group than control group. FD values of corpus and angulus values did not show a significant difference between the groups.

Conclusions

Fractal analysis may be used and recommended for evaluation of the bone changes induced by hemoglobinopathies.

Effects of first permanent molar extractıon on space changes observed in the dental arch using data mining method

Aim

The high incidence of caries in first permanent molars (FPMs) makes premature extraction of these teeth common. The extraction of the permanent teeth results in various changes in the dental arch. The aim of this study was to evaluate space closure, the eruption of second permanent molars (SPMs), and changes in dental arch after extraction of the FPMs.

Materials and Methods

Eruption of 83 SPMs was recorded and radiographically developmental stage of these SPMs in the pre-extraction panoramic radiograph was assessed. Space was measured between the distal surface of the second premolar and the mesial surface of SPM.

Results

Out of 55 patients, 28 (50.9%) were males and 27 (49.1%) were females. Thirty-seven (44.6%) of 83 teeth belonged to category 1, 17 (20.5%) teeth belonged to category 2, and 5 (6.02%) teeth belonged to category 3. Although category 4 was not found, 24 (28.9%) teeth were observed to be in category 5. Out of all SPMs, 10.8% represented the ''ideal'' stage of Demirjian's dental development, stage E.

Conclusion

In patients who had the FPMs extracted before the eruption of the SPM, it is important with regards to the patients' comfort and health to review the patient regularly and to determine any need for orthodontic treatment.