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Biomedical subjects

Francesco Cairo

Publications and source records attributed to Francesco Cairo.

8 recordsLinked to original sources

Balloonborne lidar for cloud physics studies.

An innovative balloonborne microjoule lidar (MULID) has been developed within the framework of the HIBISCUS project to provide nighttime measurements of visible and subvisible cirrus and aerosols. MULID has been designed to be a low-cost and an ultralow consumption instrument, due to the remote possibilities of payload recovery and the necessity of a low-weight battery power supply. Ground tests have been performed at the Observatory of Haute Provence (France), and the first technical flight has been made from Trapani, Italy, on a stratospheric balloon; finally, the instrument has been scientifically deployed during the pre-HIBISCUS and HIBISCUS tropical campaigns in Bauru, Brazil, in February 2003 and February 2004, respectively. A description of the instrument is provided together with the results of the ground-based and flight tests as well as an overview and discussion of the first results.

Journal Article↗

The potential prognostic value of some periodontal factors for tooth loss: a retrospective multilevel analysis on periodontal patients treated and maintained over 10 years.

BACKGROUND: The great challenge in clinical periodontology is assigning a prognosis to a periodontally affected patient. Many different factors can affect the long-term maintenance of periodontally compromised teeth. The main questions usually considered by the periodontist are: 1) Will a tooth lose more bone in the future? 2) Will the tooth itself be lost in the future? The purpose of this retrospective study was to evaluate the value of some clinical, genetic, and radiographic variables in predicting tooth loss in periodontal patients (aged 40 to 60 years) treated and maintained for 10 years. METHODS: Sixty consecutive non-smoking patients (aged 46.77 +/- 4.96 years) with moderate to severe chronic periodontitis (CP) were treated with scaling and root planing (SRP). Some patients also underwent additional surgical treatments. All patients were maintained in the same private practice for 10 years. The frequency of recall appointments was 3.4 +/- 1.0 months. At baseline (T(0)) and 10 years later (T(2)) the following clinical variables were evaluated: the number of teeth, probing depths (PD), tooth mobility (TM), and presence of prosthetic restorations (PR). In addition, radiographic measurements were taken of the mesial and distal distances from the cemento-enamel junction (CEJ) to the bottom of the defect (BD), to the bone crest (BC), and to the root apex (RA). At T(2), a genetic test to determine the IL-1 genotype and genetic susceptibility for severe periodontal disease was performed for all 60 patients, and they were classified as IL-1 genotype positive (G+) or negative (G-) according to the test results. Tooth loss was used as the outcome variable. Different predictor variables were then tested using a two-level statistical model (patient and tooth levels). At the patient level, these were: age, gender, mean bone loss (mean CEJ-BD)(T0), the interleukin-1 (IL-1) genotype, the interaction between mean bone loss, and IL-1 genotype (mean CEJ-BD(T0) x IL-1 genotype). At the tooth level, the variables were: TM(T0), prosthetic restorations (PR)(T0), molar teeth (MT)(T0), the infrabony component of the defect (BC-BD)(T0), PD(T0), bone level (CEJ-BD)(T0), and residual supporting bone (BD-RA)(T0). RESULTS: Among the considered predictor variables, the following were significantly associated with the outcome variable: 1) MT(T0) (P <0.0001); 2) BC-BD(T0) (P = 0.0377); and 3) BD-RA(T0) (P <0.0001). MT(T0) were found to be more prone to loss and the amount of BD-RA(T0) prognostic for tooth loss: the lower the residual amount of supporting bone, the higher the probability of tooth loss. Conversely, the BC-BD(T0)was associated with a reduced probability of future tooth loss: the greater the infrabony component, the lower the probability of tooth loss. None of the other considered predictors proved predictive for tooth loss. CONCLUSIONS: Within the scope of this study, many traditional prognostic factors were ineffective in predicting future tooth loss and, therefore, were of no prognostic value. Conversely, a few specific factors at the tooth level emerged as viable prognostic factors. The use of these factors may be of great value to practitioners as predictors of tooth loss when assigning a prognosis.

Adult↗

Determination of polar stratospheric cloud particle refractive indices by use of in situ optical measurements and T-matrix calculations.

A new algorithm to infer structural parameters such as refractive index and asphericity of cloud particles has been developed by use of in situ observations taken by a laser backscattersonde and an optical particle counter during balloon stratospheric flights. All three main particles, liquid, ice, and a no-ice solid (NAT, nitric acid trihydrate) of polar stratospheric clouds, were observed during two winter flights performed from Kiruna, Sweden. The technique is based on use of the T-matrix code developed for aspherical particles to calculate the backscattering coefficient and particle depolarizing properties on the basis of size distribution and concentration measurements. The results of the calculations are compared with observations to estimated refractive indices and particle asphericity. The method has also been used in cases when the liquid and solid phases coexist with comparable influence on the optical behavior of the cloud to estimate refractive indices. The main results prove that the index of refraction for NAT particles is in the range of 1.37-1.45 at 532 nm. Such particles would be slightly prolate spheroids. The calculated refractive indices for liquid and ice particles are 1.51-1.55 and 1.31-1.33, respectively. The results for solid particles confirm previous measurements taken in Antarctica during 1992 and obtained by a comparison of lidar and optical particle counter data.

Algorithms↗

Root curvature: differences among dental morphotypes and modifications after mechanical instrumentation.

BACKGROUND: This study was designed to describe a method for measuring root curvature of extracted teeth, compare root curvature of four different dental morphotypes before mechanical instrumentation, and measure root curvature after mechanical instrumentation. METHODS: Fifty-five maxillary (14 central incisors, 13 lateral incisors, 14 cuspids, 14 premolars) extracted teeth were analyzed. Measurements were recorded on the horizontal plane at the most apical point of the cemento-enamel junction (CEJ). A 4 mm wide root portion on the buccal aspect was selected and recorded on this plane. A digital scanner traced the circle coinciding with the profile of this root portion and calculated its radius, arc, chord, and arrow (i.e., the perpendicular bisector of the chord). Since root curvature is the inverse of the radius (1/r), the radius was related to root curvature; the arc to the mesio-distal dimension of the root portion; and the reduction of the arrow to root flattening after mechanical instrumentation. The measurements were recorded four times: before treatment (baseline), after polishing, after a first root planing, and after a second root planing. The radii of each dental morphotype (upper central incisors, upper lateral incisors, upper canines, upper premolars) recorded in the first measurement were calculated and used for the statistical analyses: one-way analysis of variance (ANOVA) test and the Tukey multiple comparison method were used to study the curvature. The measurements of the radius, the arc, and the arrow at the four times were used for the statistical analyses: the two-way ANOVA test and the Tukey multiple comparison method were applied in the study of the root modifications after mechanical instrumentation. The accuracy and reliability of the method were also evaluated. RESULTS: The mean radii of the four dental morphotypes were: central incisors: 3.613 +/- 0.258 mm; lateral incisors: 2.558 +/- 0.256 mm; canines: 2.822 +/- 0.238 mm; and premolars: 2.321 +/- 0.179 mm. The statistical analyses revealed differences among central incisors, canines, lateral incisors, and premolars. There was no statistically significant difference between lateral incisors and premolars. Regarding the root modifications after mechanical treatment, the radius did not show statistically significant differences in any of the comparisons. The arc and the arrow did not show significant differences between baseline and polishing, while they did show significant differences after the second root planing. CONCLUSIONS: This study indicates that: 1) the method of measuring is accurate and reliable; 2) there are statistically significant differences among the root curvatures of different dental morphotypes; and 3) polishing did not modify the root. A vigorous root planing did not modify root curvature, but it did reduce the mesio-distal dimension and flatten the root surface slightly.

Analysis of Variance↗

Prevention of alveolar ridge deformities and reconstruction of lost anatomy: a review of surgical approaches.

Prevention and treatment of alveolar ridge deformities aim at preserving and/or reconstructing soft and hard tissues of the edentulous ridge. Different surgical techniques may be used to prevent ridge collapse before tooth extraction or to reconstruct lost ridge anatomy before tooth replacement. In cases of mild or moderate ridge defects, soft tissue augmentation is generally sufficient to repair the deformity. On the other hand, hard tissue augmentation should be selected primarily when implant therapy is scheduled. In cases of severe ridge defects, a staged or a combined approach may be appropriate. This article reviews the various approaches for the prevention and treatment of ridge deformities.

Alveolar Bone Loss↗

An autologous cell hyaluronic acid graft technique for gingival augmentation: a case series.

BACKGROUND: An autologous cell hyaluronic acid graft was used for gingival augmentation in mucogingival surgery. METHODS: Seven sites from 6 patients were used in this study. Five patients (5 sites) needed gingival augmentation prior to prosthetic rehabilitation, and one patient (2 sites) needed augmentation because of pain during daily toothbrushing. Full-mouth plaque score (FMPS), full-mouth bleeding score (FMBS), probing depth (PD), and clinical attachment level (CAL) were recorded for the sites at baseline and 3 months after surgery. The amount of keratinized tissue (KT) was measured in the mesial, middle, and distal sites of each involved tooth. A small 2 x 1 x 1 mm portion of gingiva (epithelium and connective tissue) was removed from each patient, placed in a nutritional medium, and sent to the laboratory. The gingival tissue was processed: keratinocytes and fibroblasts were separated and only fibroblasts were cultivated. They were cultured on a scaffold of fully esterified benzyl ester hyaluronic acid (HA) and returned to the periodontal office under sterile conditions. During the gingival augmentation procedure, the periosteum of the selected teeth was exposed, and the membrane containing cultivated fibroblasts was adapted to and positioned on the site. RESULTS: Three months after surgery, an increased amount of gingiva was obtained, and the histological examination revealed a fully keratinized tissue on all the treated sites. CONCLUSION: Tissue engineering technology using an autologous cell hyaluronic acid graft was applied in gingival augmentation procedures and provides an increase of gingiva in a very short time without any discomfort for the patient.

Absorbable Implants↗

The prognostic value of several periodontal factors measured as radiographic bone level variation: a 10-year retrospective multilevel analysis of treated and maintained periodontal patients.

BACKGROUND: Assigning a prognosis to a periodontal patient is one of the greatest challenges in clinical practice. Many different factors can affect the result of periodontal therapy. The purpose of this study was to evaluate the prognostic value of some clinical, genetic, and radiographic variables in predicting bone level variation in periodontal patients (aged 40 to 60) treated and maintained for 10 years. METHODS: Sixty consecutive non-smoking patients (mean age 46.77 +/- 4.96) with moderate to severe chronic periodontitis were treated with scaling and root planing (SRP). Some patients also underwent additional surgical treatments. All patients were maintained in the same private practice for 10 years. At baseline (T0) and at least 10 years later (T2), the following clinical variables were evaluated: probing depth (PD), tooth mobility (TM), presence of prosthetic restorations (PR), and molar teeth (MT). In addition, radiographic measurements were taken of the mesial and distal distances from the cemento-enamel junction (CEJ) to the bottom of the defect (BD), to the bone crest (BC), and to the root apex (RA). At T2, a genetic test to determine the IL-1 genotype and genetic susceptibility for severe periodontal disease was performed for all 60 patients. Based on the results of this assay, the patients were categorized as IL-1 genotype positive (G+) or negative (G-). The differences between the bone levels measured at T0 and T2 (ABD), indicating the bone level variation, was used as the outcome variable. Different predictor variables were then tested using a 3-level statistical model (multilevel statistical analysis; patient, tooth, and site level). At the patient level these were: age, gender, and interaction between mean bone loss and the IL-1 genotype (mean CEJ-BD(T0) x IL-1 genotype). At the tooth level the variables were: TM(T0), PR(T0), MT(T0); and at the site level the evaluated factors were: the infrabony component of the defect (CEJ-BD(T0) - CEJ-BC(T0), PD(T0), bone level (CEJ-BD(T0)), and the residual supporting bone (BD-RA(T0)). RESULTS: Among the considered predictor parameters, the following were significantly associated with the outcome variable: 1) mean CEJ-BD(T0) x IL-1 genotype (P = 0.0019); 2) TM(T0) (P < 0.0000); 3) CEJ-BD(T0) (P < 0.0000); 4) CEJ-BD(T0) - CEJ-BC(T0) (P < 0.0000); 5) PD(T0) (P = 0.0010). Deeper probing depths at a site and tooth mobility at baseline were associated with worst prognosis. Greater CEJ-BD(T0) distance and infrabony component at a site at baseline were associated with a better prognosis. The interaction between mean CEJ-BD measurement at baseline and IL-1 genotype was significantly associated both with a good or a poor prognosis. The other parameters evaluated - age, gender, presence of molars and prosthetic restorations, and residual supporting bone - were not significantly associated with bone level variation. CONCLUSIONS: Within the scope of this study design, many traditional prognostic factors were ineffective in predicting future bone level variation and therefore were of no prognostic value. Conversely, a few specific factors at each level emerged as valuable prognostic factors. At the patient level, the prognostic factor was initial mean bone level in conjunction with a positive IL-1 genotype. At the tooth level, the prognostic factor was tooth mobility. At the site level, the significant prognostic factors were initial bone level at a site, the infrabony component of a defect, and initial probing depth at a site. The use of these factors may be of value to clinicians as predictors of bone level variation when assigning a prognosis to a patient, a tooth, or a site.

Adult↗