Accuracy and reliability of cone beam computed tomographic measurements of the bone labial and palatal to the maxillary anterior teeth.

PURPOSE: The aim of this study was to measure the thickness of bone labial and palatal to maxillary anterior teeth on cone beam computed tomographic (CBCT) images and to compare these measurements with direct clinical measurements to determine the reliability and accuracy of CBCT. MATERIALS AND METHODS: Eighteen healthy subjects were randomly selected from among candidates for immediate implant placement in the anterior maxilla. After extraction, labial bone thickness was measured at 1, 4, and 8 mm from the bone crest. Palatal bone thickness was also measured at 1 and 4 mm from the bone crest. The same measurements were performed on presurgical CBCT images. The CBCT measurements were compared to the direct measurements, and their accuracy and reliability were assessed by Pearson correlation coefficients and intraclass correlation coefficients, respectively. RESULTS: The mean width of labial bone was 0.50 ± 0.32 mm and 0.76 ± 0.37 mm for direct and CBCT measurements, respectively. Average thickness of the palatal bone was 1.16 ± 0.53 mm and 1.41 ± 0.51 mm for direct and CBCT measurements, respectively. The mean absolute error and mean relative error of CBCT measurements compared to direct measurements were 0.28 ± 0.29 mm and 0.60 ± 0.84 mm, respectively. The Pearson correlation between CBCT and direct measurements was 0.795 (P < .001) and the intraclass correlation coefficient between direct and CBCT measurements was 0.840. The correlation between the measurement series increased significantly when the measured bone was more than 1 mm thick. CONCLUSION: CBCT measurements of labial bone mostly overestimated bone thickness. CBCT has relatively good accuracy and reliability for measurement of labial bone thickness when the alveolar bone is thicker than 1 mm. However, most subjects have labial bone thinner than 1 mm; therefore, CBCT could result in large errors in many patients.

Diagnostic Accuracy of Inverted and Unprocessed Digitized Periapical Radiographs for Detection of Peri-Implant Defects.

OBJECTIVES: This study aimed to compare the diagnostic accuracy of inverted and unprocessed digitized periapical radiographs for detection of peri-implant defects. MATERIALS AND METHODS: A total of 30 osteotomy sites were prepared in three groups of control, study group 1 with 0.425 mm defects and study group 2 with 0.725 mm defects using the SIC and Astra Tech drill systems with 4.25mm and 4.85mm diameters. Small and large defects were randomly created in the coronal 8mm of 20 implant sites; implants (3.4mm diameter, 14.5mm length) were then placed. Thirty periapical (PA) radiographs were obtained using Digora imaging system (Soredex Corporation, Helsinki, Finland), size 2 photostimulable storage phosphor (PSP) plate sensors (40.0mm×30.0mm) and Scanora software. Unprocessed images were inverted using Scanora software by applying image inversion and a total of 60 images were obtained and randomly evaluated by four oral and maxillofacial radiologists. Data were analyzed using the t-test. RESULTS: Significant differences were observed in absolute and complete sensitivity and specificity of the two imaging modalities for detection of small and large defects (P<0.05). Unprocessed digital images had a higher mean in terms of absolute sensitivity for detection of small defects, complete sensitivity for detection of large peri-implant defects and definite rule out of defects compared with inverted images. CONCLUSION: Unprocessed digital images have a higher diagnostic value for detection of small and large peri-implant defects and also for definite rule out of defects compared with inverted images.

Bone regeneration with a combination of nanocrystalline hydroxyapatite silica gel, platelet-rich growth factor, and mesenchymal stem cells: a histologic study in rabbit calvaria.

OBJECTIVE: This study aimed to assess NanoBone as a carrier construct for mesenchymal stem cells (MSCs) and platelet-rich growth factor (PRGF). STUDY DESIGN: In the calvarial bone of 8 mature New Zealand White male rabbits, four 8-mm defects were created. Each defect received one of the following treatments: Group 1, 0.2 mg Nano-hydroxyapatite (HA) granule + 2 mL culture medium; Group 2, 0.2 mg Nano-HA + 1 mL autologous PRGF + 2 mL acellular culture medium; Group 3, 0.2 mg Nano-HA + 2 mL culture medium containing 100,000 autogenous MSCs; Group 4, 0.2 mg Nano-HA + 2 mL culture medium containing 100,000 autogenous MSCs + 1 mL autologous PRGF. RESULT: Histomorphometric analysis at 6 and 12 weeks demonstrated significantly higher bone formation in group 4 (29.45% and 44.55%, respectively) (P < .05). Bone formation in groups 1, 2, and 3 were as follows: 11.35% and 32.53%, 29.10% and 39.74%, and 25.82% and 39.11%, respectively. CONCLUSIONS: NanoBone with MSCs and PRGF seems to be an effective combination for bone regeneration in a rabbit calvaria model.

Massive craniofacial intraosseous vascular malformation resembling cystic angiomatosis: report of 2 cases and review of the literature.

Cystic angiomatosis of bone is a rare condition of multifocal angiomas of the skeleton. The condition is believed to be congenital, grows slowly and starts in first decades of life. Two cases of progressive bimaxillary enlargement, presented here with a history of slowly enlargement of facial bones when they were 9 and 6 year old, respectively. Radiographic evaluation of the craniofacial bones revealed aggressive hypertrophy with severe displacement of the teeth. The histopathological evaluation of the gross specimen showed vital bone containing capillary and cavernous spaces with endothelial lining. Aggressive cystic angiomatosis of the facial bones was described here as the most probable diagnosis.