Detection of Dental Caries and Cracks with Quantitative Light-Induced Fluorescence in Comparison to Radiographic and Visual Examination: A Retrospective Case Study.

The aim of this study was to present an optimal diagnostic protocol by comparing and analyzing a conventional examination and the quantitative light-induced fluorescence (QLF) technique. Selected were 297 teeth of 153 patients to take QLF images and bitewing radiographs. Occlusal dental caries, proximal dental caries and cracks were evaluated and scored using QLF, X-ray and/or visual criteria. The sensitivity, specificity, and area under the curve (AUC) of a receiver operating characteristic analysis were calculated. Two fluorescence parameters (|ΔFmax| and ΔRmax) were utilized to evaluate the fluorescence pattern according to the severity of lesions based on QLF or X-ray criteria. QLF showed higher scores for detecting occlusal dental caries and cracks than the conventional method. ΔRmax increased more clearly than ΔFmax did with occlusal dental caries. The |ΔFmax| values of occlusal dental caries, proximal dental caries and cracks showed good AUC levels (0.84, 0.81 and 0.83, respectively). The ΔRmax of occlusal dental caries showed the highest AUC (0.91) and the ΔRmax of proximal dental caries showed a fail level (0.59) compared to bitewing radiographs. The QLF image could visualize and estimate the degree of occlusal dental caries or cracks. Consequently, the QLF technique may be an adjunct tool to conventional methods for the detection of occlusal caries and peripheral cracks.

Biofluorescence imaging system (BIS) Guided surgery for MRONJ: A Case Series on the Preservation of Teeth and Implants: Biofluorescence imaging system guided MRONJ surgery.

The decision of surgical margin for Medication-Related Osteonecrosis of the Jaw (MRONJ) surgery is challenging. Recently, a method involving biofluorescence imaging system (BIS) has been reported for its application in MRONJ surgery to live detection of pathologic bone tissue from vital bone, which cannot be distinguished during conventional surgery. This case series aimed to assess the outcomes of adjacent teeth and implants near the lesion site in MRONJ patients who underwent BIS-guided MRONJ surgery. This retrospective study was assessed the radiographic and clinical outcomes of seven patients who underwent MRONJ surgery with BIS guidance but chose not to remove adjacent teeth or implants near the lesion. A total of seven patients (1 male, 6 females, 77.2 ± 4.7 years) were included in the study. Four implants and four teeth adjacent to the lesion were preserved. Over an average duration of 8.7 months, all subjects exhibited normal soft tissue healing and function without any complications. In conclusion, the BIS guided MRONJ surgery can be considered a minimally invasive and effective approach.

Development and Validation of Polymer-based Porphyrin-Incorporated Reference Materials for Calibration of Quantitative Light-induced Fluorescence device.

BACKGROUND: This study aimed at developing and validating polymer-based reference materials with varying amounts of porphyrin to accurately assess and calibrate quantitative light-induced fluorescence (QLF) device. METHODS: Reference materials with porphyrin concentrations ranging from 0 to 0.08 wt.% were prepared. The surface properties of the materials were analyzed via gloss and roughness measurements. Color analysis of the specimens was performed on black and white backgrounds with or without filters using a spectrophotometer. This approach revealed the correlations between fluorescence and color. The fluorescence emitted by the specimens was analyzed by measuring ΔR and ΔRmax values using a QLF-D BiluminatorTM. RESULTS: The surface gloss and roughness of the reference materials were not affected by the porphyrin content (p > 0.005). Spectrophotometric measurements revealed significant color differences among most specimen groups depending on the background color and the presence of a filter. QLF-D imaging revealed significant differences in fluorescence (ΔR and ΔRmax) among all specimen groups regardless of the background. The fluorescence values observed on the black backgrounds were higher than those observed on the white backgrounds (p < 0.05). CONCLUSIONS: The developed polymer-based porphyrin-incorporated materials serve as reliable reference standards for accurate assessment and calibration of QLF devices. This study demonstrates the importance of background conditions in fluorescence detection and highlights the potential of these materials as standards for QLF device calibration.

Noninvasive detection of microleakage in all-ceramic crowns using quantitative light-induced fluorescence technology.

The early noninvasive detection of crown microleakage is very important for tooth maintenance and preservation. A crown margin in a subgingival position combined with the obscuring effect of a ceramic crown make it difficult to diagnose microleakage using traditional methods such as visual-tactile examinations and radiography. The aim of this study was to determine the effectiveness of quantitative light-induced fluorescence (QLF) technology for diagnosing microleakage in an all-ceramic crown noninvasively. In this study the red fluorescence glow was detected through a crown wall using the Qraycam QLF device (AIOBIO, Seoul, Republic of Korea). No abnormalities were detected by a visual examination, whereas the Qraycam device revealed both strong red fluorescence and fluorescence loss in suspicious lesions, which were confirmed after crown removal. It was possible to determine that the carious lesions inside the crown were related to bacteria-induced microleakage. After performing caries removal and crown reattachment, the red fluorescence glow was no longer detected. QLF examinations made it easy to identify the presence of microleakage in an all-ceramic crown noninvasively based on red fluorescence. These findings indicate that QLF technology can be effectively applied to provide objective evidence for detecting microleakage and diagnosing carious lesions inside an all-ceramic crown noninvasively.

Effects of different depths of gap on healing of surgically created coronal defects around implants in dogs: a pilot study.

BACKGROUND: This study investigated the bone growth pattern in surgically created coronal defects with various depths around implants in dogs. METHODS: Four mongrel dogs were used. All mandibular premolars were extracted under general anesthesia and left to heal for 2 months. After ostectomy, bony defects were prepared in test sites, using a stepped drill with a diameter of 6.3 mm and two depths: 2.5 mm (test sites 1 [T1]) and 5.0 mm (test sites 2 [T2]). In the control sites, the implants were placed after ostectomy without any coronal defects. T1, T2, and control sites were prepared in the right and left sides of the mandible. Six implants, 3.3 mm in diameter and 10 mm in length, were placed in each dog; the implants were submerged completely. Two dogs were sacrificed 8 weeks after surgery, and the other two dogs were sacrificed 12 weeks after surgery. The stability of all implants was measured with a resonance frequency analyzer after placement and after sacrifice. All sites were block-dissected for ground sectioning and histologic examination. RESULTS: After 12 weeks of healing, only T2 were not filled fully with bone. At week 8, the mean bone-to-implant contact (BIC) was 47.7% for control, 43.6% for T1, and 22.2% for T2. At week 12, the control BIC was 56.7% and the 2.5-mm defect had a greater BIC (58.8%). However, in the 5-mm defect, the BIC was 35.1%. At insertion, stability was reduced at sites with a greater defect depth. Similar stability was noted in all specimens after 8 and 12 weeks of healing. CONCLUSION: Bone healing between an implant and marginal bone was compromised at sites with a deeper defect when the width of the bone defect was 1.5 mm.

Immediate provisionalization of mini-implants with friction-engaging abutments in the mandibular anterior region: a 1-year retrospective study.

This study evaluated the immediate provisionalization of mini-implants with friction-engaging abutments in the mandibular anterior region. A total of 43 mini-implants placed in 30 consecutive patients had a survival rate of 100% over a follow-up period of 1 to 4 years. The overall change in marginal bone level from definitive restoration delivery to 1 year for a single-tooth mini-implant replacement was -0.17 ± 0.42 mm, demonstrating bone gain. The mean changes in marginal bone level on the mesial and distal aspects were -0.18 ± 0.46 mm and -0.16 ± 0.40 mm, respectively, also representing bone gain. The difference between the mesial and distal change in bone level was not statistically significant (P = .93). The peri-implant soft tissue remained relatively unchanged at 1 year posttreatment.