Classification of dental diseases using hyperspectral imaging and laser induced fluorescence.

PURPOSE: Early diagnosis of tooth enamel demineralization, and dentin caries lesions, present a valuable solution to avoid or decrease their deleterious effect. The aim of this study was to design a simple, effective, and non-invasive technique, employing a novel laser wavelength to classify and differentiate between various tooth abnormalities in-vitro, by estimating wavelengths, showing distinctive appearance for each tooth class. METHODS: This study implies a fluorescence hyperspectral imaging system employing a 395-nm laser diode source, irradiating a pre-diagnosed 12 molars and premolars teeth. The obtained reconstructed images were displayed and processed by HSAnalysis2XL, accompanied by a custom made digital, and image signal processing algorithms, revealing the exact wavelengths, characterizing the fluorescence of each tooth pre-diagnosed class. RESULTS: The proposed hyperspectral imaging system was able to discriminate between normal, and abnormal dental classes for the entire specimens. Furthermore, a series of wavelengths, noting each lesion individually were obtained from the spectroscopic hyperspectral output. The root calculus, white spot, dentin caries, and enamel caries have a bright visual appearance at λ3 = 702 nm, λ5 = 771 nm, and λ6 = 798 nm respectively. Consequently, these abnormalities exhibit a dark appearance at λ1 = 421 nm, λ2 = 462 nm, and λ4 = 734 nm. The wavelength selections were confirmed by the grayscale image outcomes. CONCLUSIONS: This study provides a set of wavelengths that can be employed by dentists to diagnose white spot, root calculus, and enamel dentin caries lesions under the irradiation of a new UV-vis laser illumination source without, any hazardous thermal or mechanical effects.

Can the rate of cesarean section be reduced?

OBJECTIVE: To look into all cases with previous one cesarean section who were cared for and delivered at Armed Forces Hospital, Riyadh, between January 1990 and December 1998, to determine its prevalence, final method of delivery, and outline measures of reducing its incidence. METHODS: Retrospective analysis of hospital records of all women with previous one cesarean section who had either a repeat cesarean section or delivered vaginally after cesarean section. RESULTS: Between 1990 and 1998, 61,060 mothers were delivered. Two thousand five hundred and seventy eight patients had one previous cesarean section. They represented 3.5% of the total number of deliveries. Nine hundred and sixty eight (37.5%) cases had repeat cesarean section. Of the 1610 (62.5%) mothers who achieved vaginal delivery, 102 (6%) had ventouse, 42 (3%) had forceps and 22 (1%) had an assisted breech delivery. Rupture of uterine scar was reported in 15 cases. There were no maternal or perinatal deaths. CONCLUSION: Patients with one previous cesarean section are three times more likely to have a cesarean section as compared to mothers with unscarred uterus. Reducing the overall cesarean section rate is possible through a closer look at the primary indication for the first cesarean section. A protocol is needed to allow more cases with one or more previous cesarean section to have trial of vaginal delivery under close monitoring and involve the senior staff more in the diagnosis and management of cases of dystocia and the use of Oxytocin when indicated.

Transabdominal cervicoisthmic cerclage.

Full text is available as a scanned copy of the original print version.

Intrapartum rupture of the gravid uterus.

Full text is available as a scanned copy of the original print version.