Search PubMed⌕ Search

Biomedical subjects

J C Franquin

Publications and source records attributed to J C Franquin.

At least 37 records · Page 2Linked to original sources
PubMed1996

The use of a resorbable membrane in mucogingival surgery. Case series.

A surgical technique involving a resorbable membrane was used to treat 3 to 7 mm localized human buccal recessions on 10 consecutive patients. The exposed root surface was scaled and a trapezoidal mucoperiosteal flap was elevated after de-epithelization of the papillae. The space between the root and the membrane was created using a bur to form a concavity on the root and by bending the membrane with a suture. The flap was positioned as coronally as possible covering the membrane. The sutures were removed 15 days postsurgery and tetracycline therapy prescribed for 10 days. The results were evaluated at 12 months. The surgical procedure resulted in a significant reduction in recession (2.9 mm +/- 1.3) as well as a gain in attachment (3.4 mm +/- 2.1). Calculation of mean root coverage was 59.6%. There was no significant change of the keratinized tissue width. For therapeutic reasons, re-entry was performed in 2 cases: newly formed tissue was observed on the previously exposed roots. Guided tissue regeneration using a resorbable membrane appears to provide good results in cases of localized buccal recession.

Adult↗
PubMed1995

Helium-neon laser effects on conditioning-induced oral mucositis in bone marrow transplantation patients.

BACKGROUND: Oral mucositis is a common complication of bone marrow transplantation (BMT) conditioning therapy. Sequelae consist of increased risk for infection, moderate to severe pain, compromised oral function, and bleeding. This study investigated helium-neon laser treatment for prevention of conditioning-induced oral mucositis in BMT patients. Patterns and severity of mucositis for specific conditioning drug regimens also were analyzed. METHODS: Twenty patients received laser radiation to their oral mucosa, either left or right of midline. The contralateral side was sham-treated and served as a control. Mucositis severity was scored independently by two modified versions of the Oral Mucositis Index Scale (OMI-A and OMI-B) and the Eastern Cooperative Oncology Group (ECOG) Oral Toxicity Scale; pain severity was scored by subjects on a visual analogue scale (VAS). Cumulative scores were analyzed for differences between the laser-treated and sham-treated sides. RESULTS: Oral mucositis and pain scores were significantly lower for the treated versus the untreated side by OMI-A and B (P < 0.005) and VAS (P = 0.027) criteria, respectively. Ulcerative lesions occurred in all patients bilaterally; severity increased until Day +6, and lesions resolved by Day +21. Mucositis was more severe for patients conditioned with busulfan/carboplatin/thiotepa than for patients conditioned with busulfan/cyclophosphamide/etoposide. CONCLUSIONS: Helium-neon laser treatment was well-tolerated and reduced the severity of conditioning-induced oral mucositis in BMT patients.

Adult↗
PubMed1993

Biocompatibility testing of restorative materials influencing dentin and pulp.

A comparative study was carried out using 27 healthy human bicuspids that had been extracted for orthodontic reasons from adolescents 11-14 years old. A microphotometrical analysis of buccal and lingual odontoblast layer thickness was performed using the SAMBA 2000 system and the results were submitted to statistical comparison. The buccal odontoblast layer (BOL) was found to be thicker than the lingual odontoblast layer (LOL). These results were independent of age, sex, and tooth position in the dental arch. Moreover, a strong relationship existed between the layer thicknesses as linear function on a logarithmic scale. Standards for the evaluation of pulp-dentin biocompatibility are based essentially upon qualitative or semiquantitative histological criteria. A method of quantitative evaluation based upon microphotometrical measurements of the thickness of the buccal odontoblast layer, considered variable, and the lingual odontoblast layer, considered stable, was applied to coronal filling materials that had previously been tested by a classic method. Seventy bicuspids extracted from adolescents 11-14 years of age whose class-V cavities had been filled in situ with one of four restorative materials, and whole residual dentin thickness was less than 750 microns, were divided into two groups: an intermediate-term group (A) and a long-term group (B); both groups were subdivided into four experimental series as a function of test materials. A microphotometrical analysis was carried out using an automatic scanning system (SAMBA 2000) for the quantification of buccal and lingual odontoblast layer thicknesses. The results confirmed that due to the stability of the LOL thickness it may legitimately be used as reference in the study of the analogous BOL thickness.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1992

Effects of culture passages on collagen immunostaining in human dental pulp and gingival fibroblasts.

In this study, a scanning microscopic computer-assisted image analysis system was used for the immunocytochemical characterisation of collagen types I, III and V in normal human fibroblasts from pulp and gingival explants, using specific purified antibodies and peroxidase labeling. The culture conditions were standardized in order to evaluate simultaneously the expression of the three antigens in four different culture passages of the two fibroblast types. The optical density values of immunostaining intensities were quantified, the integrated optical density per cell was calculated, and the results were analyzed by a variance test. It was found that all three collagen types were present in the tissues, and in both gingival and pulp fibroblasts after three to nine culture passages. A non-parametric statistical analysis of the staining intensity variances revealed significant differences between antigenic levels depending on the tissue origin of the fibroblasts and an effect of culture passages. The results seemed to justify application of this technique at the light microscope level for the evaluation of collagen production, the principal function of fibroblasts, but the tissue origin and number of culture passages should be taken into consideration for in vitro biocompatibility testing of dental materials.

Adult↗
PubMed1992

[Laser therapy in the prevention and treatment of mucositis caused by anticancer chemotherapy].

The appearance of mucositis is a frequent and painful secondary effect of anticancer chemotherapy. Patients who develop oral toxicity during the first course of treatment will almost assuredly show identical side effects during each subsequent course unless the drugs are changed or the doses are lowered. In the absence of an efficacious antidote or preventive prophylaxis for such lesions to date, this report presents the results of a preliminary retrospective non-randomized study of the effect of soft-laser treatments on mucositis in cancer patients receiving combination chemotherapy, including 5-fluorouracil. Iatrogenic mucositis was observed during 43% of 53 chemotherapy cycles in the case control population. Curative laser therapy reduced the time to repair lesions and the rate of therapeutic modifications. For patients who received soft-laser therapy as a preventive measure, the incidence of oral complications was reduced to 6% during 101 cycles of chemotherapy. All of these patients, even those who have encountered mucositis before receiving preventive laser therapy, terminated their cancer therapy as originally scheduled. Well designed and carefully controlled trials will be necessary to define the place of helium-neon laser therapy in the repair and prevention of oral complications due to cancer chemotherapy.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1990

[Osseous biocompatibility of Endomethasone(R)].

The root canal filling paste "Endométhasone" was tested, following the F.D.I. criterions by bone implants on rabbits. The tissue reaction after four weeks can be appreciated as moderate and as mild after twelve weeks. Taking in count the criterions selected and the experimental conditions of this study, the "Endométhasone" can be considered as a root canal cement with acceptable in vivo tolerance.

Administration, Topical↗
PubMed1990

[Analysis of bone-implant stress distribution. Finite element modeling].

A two-dimensional finite element partial mandibular model allows a first comparison between two types of titanium cylindrical implants, one full, the other hollow. The study cases correspond to a distal edentulous rehabilitated with a three-unit bridge supported mesially by a healthy second premolar and distally by one of the two concerned implants. The model includes the mandible from the canine region to the condyle, and allow to investigate the interactions between implants and bone tissue, under a normal biting load (100 N) distributed over the different teeth of the model. On a general way, the highest stresses magnitudes are in the implants, so there are no pathologic actions in bone, even if the distal cervical region of the implants are more stressed than any place else of the alveolar bone. It is well known that bone resorptions are often found in that region. Furthermore the bone trunk of the hollow implant is no more stressed than the rest of the mandibular, that is good for bone affixing. The outcome of this work, over the first results exposed, is that it gives the opportunity to understand the complexity of such a problem.

Alveolar Bone Loss↗
PubMed1990

Helium-neon laser treatment transforms fibroblasts into myofibroblasts.

The differentiation of myofibroblastic cells from normal human gingival fibroblasts in vitro has been established by transmission electron microscopy and quantitated by immunohistochemistry, using antigelsolin monoclonal antibodies. Untreated control cultures were compared to cultures exposed to Helium-Neon (He-Ne) laser irradiation. A direct and massive transformation of the cultured fibroblasts into myofibroblasts was observed as early as 24 hours after laser treatment, whereas control cultures were comprised of only resting fibroblasts and active fibroblasts. This in vitro induction of myofibroblasts may be analogous to that which occurs in vivo. Therefore we undertook a similar study using biopsies from gingival tissues after wisdom tooth extraction. Myofibroblasts were present in the connective tissue of laser-treated gums 48 hours after irradiation, but not in untreated contralateral control tissues. These data provide evidence that the primary biologic effect of the Helium-Neon laser on connective tissue is the rapid generation of myofibroblasts from fibroblasts. The induction of a phenotype with contractile properties may have clinical significance in the acceleration of the wound-healing process.

Actins↗
PubMed1989

[Induced remineralization of carious dentin. Electronic microprobe analysis].

Our electron microprobe studies show the preferential incorporation in vitro of tin and fluorure into carious dentin. These ions do penetrate only into carious dentin through the body of the lesion. These ions do not progress through the sclerotic dentin barrier, when it exists which tend to demonstrate their affinity for demineralized tissues. Results of microprobe analysis may suggest the hypothesis of a crystalline arrangement as the product of reaction between residual apatite in carious dentin with stannous fluoride. A new crystalline phase could occur within the carious zone, up to the sclerotic barrier. This method does not permit to indicate its identity or its structure. However, it has been recognized in previous studies as a tin phosphate compound. Further analytic studies, using crystallographic technics of the treated zones could provide additional data of the observations from the electron microprobe and confirm the hypothesis of the ability of carious dentin to be remineralized by the use of stannous fluoride containing solutions or materials.

Dental Caries↗
PubMed1989

[Evaluation of the cytotoxicity of two capping materials: in vitro cell culture study].

Evaluation of the biocompatibility of a crown reconstruction material in vivo on human teeth by histologic observation of pulpal reactions is a long lasting and expensive procedure. Before to start it, a first examination can be done by testing the material on cell cultures. If the used culture cells contain antibiotics, it is necessary to combine these tests with a bacteriologic examination of the tested material. Two calcium hydroxide containing materials for dentin-pulp capping, were submitted to cytotoxicity tests using human pulpal fibroblasts cultures. The cytotoxicity of one over the two materials could be related to its lability and bacterial contamination.

Calcium Hydroxide↗
PubMed1988

[Effect of a helium-neon laser on cellular growth: an in vitro study of human gingival fibroblasts].

For a better understanding of the clinical effects obtained with lasers of low power on oral wounds, an in vitro study was conducted on human fibroblasts obtained from a primary gingival culture in order to evaluate the effect of one or several irradiations obtained with a Helium-neon laser (632.8 nm, 10 mW). An irradiation of 10 minutes (1.2J/cm2) induced a growth acceleration of the cellular population compared to a non-irradiated control population. The greatest effect was obtained four days after treatment. Furthermore, if the cells were submitted to repeated irradiations every four days, the cellular divisions increased after each treatment. A careful interpretation of these in vitro results on healing time of oral wounds in vivo would suggest that it may be due partly to a recycling actin of low power lasers on resting cells.

Cell Division↗