Biomedical subjects

Michèle Muller-Bolla

Publications and source records attributed to Michèle Muller-Bolla.

8 recordsLinked to original sources

PubMed2006

Er:YAG laser cavity preparation and composite resin bonding with a single-component adhesive system: relationship between shear bond strength and microleakage.

BACKGROUND AND OBJECTIVES: The purpose of this study was to assess the performances of a single-component adhesive system when an Er:YAG laser was used to prepare cavities. STUDY DESIGN/MATERIALS AND METHODS: Shear bond strength tests were performed on composite rods bonded with a single-component adhesive system to dentin surfaces prepared using either bur+acid, Er:YAG laser (fluence = 44 J/cm2), or Er:YAG laser+acid. Class V cavities were prepared differently according to the molar surface: buccal surfaces were prepared using a diamond bur, and lingual surfaces using the Er:YAG laser. In group 1, cavity walls were not acid treated after Er:YAG laser preparation. In group 2, only the enamel walls were acid treated. In group 3, all the enamel and dentin walls were acid treated. Microleakage was assessed using a methylene blue dye penetration method. RESULTS: Bond strength values did not differ significantly between the three groups (P = 0.162). Better marginal adaptation was obtained between the composite resin and cavity walls when Er:YAG laser preparation was followed by a total acid etching (P = 0.008). CONCLUSIONS: Our results supported the use of single-component adhesive systems in cavities prepared using Er:YAG laser. The step of acid etching must be maintained for the whole cavity walls in regard of the microleakage values.

Aluminum↗

PubMed2006

Retention of resin-based pit and fissure sealants: A systematic review.

The aim of the present study was to perform a systematic review on the retention of resin-based sealants (RBSs) according to the material used and the clinical procedure. An electronic search in MEDLINE, EMBASE, Cochrane library and SCOPUS was completed by a hand search in conference proceedings. One hundred and twenty-four studies were identified, 31 of which were included. The retention rate of auto-polymerized and light-cured RBSs did not differ significantly. Light-cured RBSs had a significantly higher retention rate than fluoride-containing light-cured RBSs at 48 months (RR = 0.80, 95% CI: 0.72-0.89) and more. Concerning the clinical procedure, the scarcity of well-conducted studies made judgement difficult, except for the isolation stage. If using a rubber dam did not affect retention of auto-polymerized RBSs, it did for fluoride-containing light-cured RBSs (RR = 2.03, 95% CI: 1.51-2.73).

Acid Etching, Dental↗

PubMed2005

Scanning electron microscopy analysis of experimental bone hacking trauma.

The authors report on their macro- and microscopy study of bone lesions made by a sharp force instrument (a single blade knife), and a sharp-blunt instrument classified as a chopping weapon (a hatchet). The aim of this work was to attempt to identify the instrument by analyzing the general class characteristics of the cuts. Each weapon was used on human bones. The results indicate that macroscopic analysis is more problematic. The microscopic analysis assessed that characteristics examined were effective in distinguishing sharp from sharp-blunt injury to the bone. The microscope facilitates analysis unachievable with macroscopic methods, some three-dimensional characteristics not visible to the naked eye being clearly defined with its use. Emphasis has been placed on the value of SEM as an anthropologist's tool in bone lesion injuries.

Femur↗

PubMed2004

Scanning electron microscopic evaluation of resin-dentin interface after Er:YAG laser preparation.

BACKGROUND AND OBJECTIVES: The aim of this study was to observe the morphological characteristics of dentin-resin interfaces when a composite resin was bonded to Er:YAG laser irradiated dentin. STUDY DESIGN/MATERIALS AND METHODS: Human dentin surfaces were divided into three equal areas. One third was prepared using a carbide bur and etched with phosphoric acid, the second third was conditioned using an Er:YAG laser, the third one was irradiated and etched. A hybrid composite resin was bonded on dentin surfaces using a single-component adhesive system. Longitudinal sections were exposed to 5 N HCl then to 1% NaOCl. The thickness of the hybrid layer and the dimensions of the resin tags were measured using scanning electron microscopy (SEM) pictures and an image analysis software. RESULTS: When acid etching was performed, a hybrid layer as well as the characteristic funnel-shaped resin tags were observed. When Er:YAG laser was used alone, no hybrid layer could be detected. The resin tags appeared thinner and exhibited a cylindrical shape. CONCLUSIONS: The acid pre-treatment of the irradiated surface allowed both the seal of the dentinal surface and the increase of the diameter of the resin tags.

Composite Resins↗

PubMed2004

Microleakage of a pit-and-fissure sealant: effect of air-abrasion compared with classical enamel preparations.

PURPOSE: The aim of this study was to assess the microleakage of a pit-and-fissure sealant after classical enamel preparations (prophylaxis followed by acid etching alone and mechanical widening with bur) and after air abrasion. MATERIALS AND METHODS: Ninety noncarious freshly extracted third molars were randomly assigned to three groups of 30. In each group, the mesial halves of the fissures were treated with air abrasion and conditioned with acid etching for 15 s. In group 1, the distal halves were treated with acid etching alone. In group 2, the distal halves of the fissures were widened mechanically with a bur and etched for 15 s. In group 3, the distal halves were prepared with air abrasion alone. Then the sealant (Clinpro) was applied on the occlusal fissures of all teeth, according to the manufacturer's recommendations. The teeth were thermocycled and the samples placed in a 1% methylene blue dye solution. The teeth showing microleakage and the means of infiltration were assessed with an image analysis system. RESULTS: The microleakage of sealants prepared with air abrasion alone displayed significantly greater microleakage (80%) (p < 0.0001) than the ones placed after prophylaxis and etching (13.33%), bur and etching (20%), or air abrasion and etching (22.2%). The samples prepared with air abrasion alone also showed the highest mean microleakage (1.14 +/- 1.4 mm) when compared to samples receiving prophylaxis and acid etching (0.12 +/- 0.41), bur and acid etching (0.08 +/- 0.26), or air abrasion and acid etching (0.09 +/- 0.4) (p < 0.05). No significant difference was noted between the three types of enamel preparation when etching was performed. CONCLUSION: Air-abrasion treatment does not eliminate the need for etching the enamel surface before applying the sealant.

Acid Etching, Dental↗

PubMed2003

Orofacial trauma and rugby in France: epidemiological survey.

A stratified epidemiological survey was carried out among the best French rugby players to assess the prevalence of trauma to the lower or middle part of the face (TLMPF) and the frequency at which the mouthguards (MGs) were worn. The 1140 randomized players (elite 1, elite 2 and national 1 clubs) filled in the same form anonymously. The variables were first subjected to univariate analysis (Chi-square, anova). Secondly, they were included in a multivariate model (logistic regression). Some 29.57% of players had already been affected by a TLMPF. The risk increased for the oldest forward players. It also increased with the number of yearly competitions and number of hours of weekly training. Some 64.3% of players used a MG. The frequency at which it was worn increased with the number of yearly competitions, for those who had experinced a previous trauma and for the pack players who had been playing for a long time.

Adult↗

PubMed2003

Age estimation from teeth in children and adolescents.

The aim of this cross-sectional study was to evaluate the dental formulas according to age because of possible changes during the last decades. From these dental formulas, the median age of emergence for the permanent teeth was deduced. The study population corresponded to the 1 to 15 year-old children who had consulted either a pediatric dentist or orthodontist in the city of Nice (France). Data were collected from the 5,848 patients' charts that included an orthopantomography. This permitted the observation of emerged teeth and agenesis. Bar charts were used to indicate the dental formula according to age. There was no significant difference in the emergence pattern of both controlateral maxillary and mandibular teeth. Only the anterior tooth emergence significantly differed according to the maxillary. The lower central incisor was the lone tooth with a median age earlier than others; the remaining teeth had an age equivalent to those of previously estimates.

Adolescent↗

PubMedDate not supplied

A survey of disinfection of irreversible hydrocolloid and silicone impressions in European Union dental schools: epidemiologic study.

PURPOSE: The objective of this cross-sectional study was to describe corresponding procedures for irreversible hydrocolloid and silicone impressions taught and used in European Union dental schools. MATERIALS AND METHODS: A self-administered questionnaire requesting information about rinsing and disinfection methods was sent to each of the 373 heads of prosthodontic, pedodontic, and orthodontic departments in the 131 European Union dental schools. Response rate was 94%. Statistical analysis included chi-square or Fisher exact tests, and ANOVA or Kruskall-Wallis tests. RESULTS: Of the responding departments, 92% systematically rinsed their impressions. Fifteen percent of the departments, mostly orthodontics, never disinfected irreversible hydrocolloid impressions, and 11% never disinfected silicone impressions. The immersion method was used by 65% for irreversible hydrocolloid impressions (73% for silicone), with a disinfection time of 10.3 +/- 6.3 minutes (11.8 +/- 7.4 for silicone). The disinfected impressions were not rinsed by 16% for irreversible hydrocolloid and 14% for silicone. Most departments used brand-name products. CONCLUSION: The same disinfection procedure for both irreversible hydrocolloid and silicone impressions was used by 78% of departments. There was great diversity, however, between departments in the procedure used for each impression material.

Alginates↗