Biomedical subjects

G Varvara

Publications and source records attributed to G Varvara.

16 recordsLinked to original sources

PubMed2005

Copper-zinc superoxide dismutase activity in healthy and inflamed human dental pulp.

AIM: To examine copper-zinc superoxide dismutase (Cu, Zn-SOD) activity in clinically healthy and symptomatic human dental pulps. METHODOLOGY: Twenty-five systemically healthy patients, 14 females and 11 males (age: 13.1-34.6 years; mean: 21.7 +/- 6.3), were the source of the pulp tissue. The condition of the pulps was assessed using clinical and radiographic evaluation. The pulp tissue was collected by longitudinally grooving and splitting the teeth (if extracted) or during endodontic treatment, and were age- and sex-matched between the healthy and the irreversible symptomatic pulpitis tissue groups. Cu, Zn-SOD activity was determined through spectrophotometric methods and a Mann-Whitney test assessed the significance of differences between the groups. RESULTS: The enzyme activities were 144.8 +/- 42.2 and 68.1 +/- 25.0 U mg(-1) in the healthy and irreversible symptomatic pulp tissue, respectively. The difference between the groups was statistically significant (P < 0.001). CONCLUSIONS: These results demonstrate a potential role for Cu, Zn-SOD during dental pulp inflammation in humans.

Adolescent↗

PubMed2003

Catalase activity in human healthy and inflamed dental pulps.

AIM: To examine the catalase activity in clinically healthy and symptomatic human dental pulps to verify if an active defence system against oxidizing agents is present as a response to bacterial invasion. METHODOLOGY: Thirty-three systemically healthy patients, 18 females and 15 males (ages: 11.0-25.9 years; mean 18.8 +/- 3.6), were the source of the pulp tissue. The condition of the pulps was assessed using clinical and radiographic evaluations. The specimens were recovered by longitudinally grooving and splitting the teeth (if extracted) or during endodontic treatment, and were matched for age and sex between the healthy and inflamed specimen groups. Catalase activity was determined through spectrophotometric methods. RESULTS: Enzymatic activity was 1126 +/- 343 and 3074 +/- 698 mU mL(-1) x mg of total protein in the healthy and inflamed pulp tissue specimens, respectively. This difference was statistically significant (P<0.01). CONCLUSIONS: These results indicate a role for catalase during dental pulp inflammation in humans, and may represent an inherent biological defence system against reactive oxidants of this tissue.

Adolescent↗

PubMed2002

Cerec 3 for orthodontics: a tool for treating deep bite.

Bite-opening procedures are used in the early stages of orthodontic fixed treatment in order to: ease antero-posterior tooth movements; bracket the mandibular arch and level the Curve of Spee; prevent mandibular brackets from debonding; use regular straight archwires to proceed with treatment. For these purposes, removable or bonded biteplanes are universally recognized as very effective when the bite-opening is needed. Conventional orthodontic procedures include clinical solutions which effectively open the bite, but they all lack sufficient hygiene, comfort, and esthetics. The authors propose the use of the CAD-CAM technology with the Cerec 3 system (Sirona, Bensheim, Germany) to create an overcrown able to open the bite through clinical crown lengthening of the mandibular second premolars. The laboratory steps are described and the clinical efficacy is demonstrated with an orthodontic case report.

Adolescent↗

PubMed2001

Root canal treatment in mandibular canines with two roots: a report of two cases.

AIM: To highlight anatomical variation in the mandibular canine. SUMMARY: Two clinical case reports are presented to illustrate anatomical variation in the human mandibular canine. Endodontic treatment may sometimes fail because morphological features of the tooth adversely affect the treatment procedures. Many investigators have reported the anatomical variations associated with mandibular canines. Mandibular canines are recognized as usually having one root and one root canal in most cases, although approximately 15% may have two canals or sometimes two roots. This paper describes two clinical cases of mandibular canines with two roots and two canals. KEY LEARNING POINTS: Failure to control infection in the root canal system has an adverse impact on outcome. Clinicians should be aware of anatomical variations in the teeth they are managing, and should never assume that canal systems are simple. The majority of mandibular canines have one root and root canal, but 15% may have two canals, and a smaller number may have two distinct roots.

Cuspid↗

PubMed2000

Localization of the e-NOS enzyme in endothelial cells and odontoblasts of healthy human dental pulp.

Nitric oxide synthases (NOS) are important enzymes present in different cells such as endothelial cells, macrophages, etc. Recently, it has been found that nitric oxide (NO) is responsible for vasodilation, blood pressure regulation, platelet aggregation, cardiac contractility, and the mediation of immunity during bacterial infections and inflammation. However, the production and role of NO in various structures of the oral cavity have not been investigated extensively. The aim of this study was to evaluate the presence of e-NOS in healthy human odontoblasts and endothelial cells of the dental pulp. Twenty healthy human dental pulps were collected and frozen and pulp slices were obtained using a cryostat. The e-NOS enzyme was revealed by immunohistochemical analysis and the enzyme level was detected by Western blotting and mRNA expression by RT-PCR. The immunohistochemical results demonstrated, for the first time, the presence of e-NOS in odontoblasts and in endothelial cells. The presence of e-NOS m-RNA was confirmed by RT-PCR and the expression of the protein by Western blotting. These results clearly show that the e-NOS enzyme is present in both odontoblasts and endothelial cells of healthy human pulp. The presence of e-NOS in the odontoblast and endothelial cells of the dental pulp may mediate local vasodilation and cell proliferation.

Blotting, Western↗

PubMed2000

Broken instrument removal--two cases.

This paper reports two clinical aids for the removal of broken instruments in root canals using a combination of hand instrumentation and ultrasonic devices. This technique is based on two phases: hand instrumentation with stainless-steel K-file instruments for bypassing the fragments, and K-files mounted on an ultrasonic handpiece for loosening and retrieval of the broken instruments. This method offers the following advantages: conservation of the remaining dentin wall of the root canal and elimination of the necessity for surgical treatment.

Adult↗

PubMed2000

Canal filling in primary teeth. Description of two particular cases.

Endopedodontics is that branch of child dentistry that regards pulp treatment in childhood. It involves endodontic treatment of all primary teeth and incisives, and of the first permanent molars with immature apex. The pedodontist has to exactly evaluate the techniques and the material to use in treating his patients. It is important to realize that we are facing a continuously evolving and absolutely unstable dentition. Therefore, the success of our work is the result of a careful evaluation of diagnostic parameters and of the techniques and the material. In the current clinical cases it is obvious how the lack of only one of the parameters listed, could represent the cause of severe damage to the patient's dental health and it could lead to psychological discomfort (if not damage), considering the age of the patient.

Child↗

PubMed1999

An evaluation of the action of different root canal irrigants on facultative aerobic-anaerobic, obligate anaerobic, and microaerophilic bacteria.

The aim of this study was to test the effect of different concentrations of sodium hypochlorite, chlorhexidine, and cetrimide on the following bacterial strains: Facultative aerobes-anaerobes: Candida albicans ATCC 10231; Enterococcus faecalis ATCC 29212; Escherichia coli ATCC 25,922; Pseudomonas aeruginosa ATCC 27,853; Streptococcus mitis ATCC 9811; Streptococcus mutans ATCC 35668; Streptococcus salivarius ATCC 13419; and Streptococcus sanguis ATCC 10556. Microaerophiles: Actinobacillus actinomycetemcomitans ATCC 29522. Obligate anaerobes: Actinomyces odontolyticus ATCC 17929; Fusobacterium nucleatum ATCC 25,586; Porphyromonas gingivalis ATCC 33277; and Prevotella melaninogenica ATCC 25845. Each irrigant was kept in contact with the bacterial species used for the experiment for 10, 20, or 30 min. Results showed that all irrigants had a bactericidal effect on both facultative aerobes-anaerobes and on microaerophilic and obligate anaerobic strains, in all concentrations and even after short periods of contact.

Anti-Infective Agents, Local↗

PubMed1998

[Alpha-hemolytic streptococci and root canal irrigants. An evaluation of the bactericidal efficacy of sodium hypochlorite and chlorhexidine gluconate plus cetrimide].

BACKGROUND AND AIMS: The main bacterial species present in pulpal and periapical microbic flora is alpha-hemolytic streptococci. They are regarded as facultative anaerobes which prefer to grow in anaerobiosis. Canal irrigation plays an important role in the success of endodontic treatment given that, on the one hand, it encourages the gradual elimination of the smear layer, and on the other it neutralises microbic flora in the root canal. The aim of this study was to test the microbiological efficacy of sodium hypochlorite 1% and s new generation irrigant based on chlorhexidine 0.2% and cetrimide 0.2%. METHODS: The test was performed on the following alpha-hemolytic streptococci bacteria (Dasit, Cornaredo, Italy): Streptococcus mitis ATCC 9811; Streptococcus mutans ATCC 35668; Streptococcus salivarius ATCC 13419; Streptococcus sanguis ATCC 10556. The working concentration (CFU/ml) was defined as 0.5 Mc Farland which corresponds to a concentration of microorganisms of approximately 1.5 x 10(8) bacteria. The following canal irrigants were used: 1) cetrimide 0.2% + chlorhexidine 0.2% (Cetrexidin Vebas, S. Giuliano Milanese, Italy); 2) NaOCl 1% (Ogna, Milan, Italy). Each individual substance remained in contact with the bacterial species used in the test for 10'-20'-30'. RESULTS: The results obtained show the bactericidal efficacy of both the irrigants used, even after a short period of contact. CONCLUSIONS: This does not mean that all irrigants are equal and/or promise the same results. This was a microbiological study, but it is nonetheless important to take other variables into account, such as contact time. Moreover, in order to increase the probabilities for the success of endodontic treatment, canal irrigants must also present other characteristics, namely: biocompatibility, scarce toxicity, high proteolytic power.

Anti-Bacterial Agents↗

PubMed1998

[A comparative in-vitro study of the bactericidal efficacy of sodium hypochlorite and chlorhexidine gluconate plus cetrimide on root canal anaerobic bacterial flora].

INTRODUCTION: The permanence of necrotic tissues and/or bacteria may be responsible for persistent root canal infection. Root canal irrigation plays an important role in the success of endodontic treatment given that, on the one hand, it encourages the progressive elimination of the smear layer and, on the other, it neutralises microbic flora within the canal. The aim of this study was to test root canal irrigants from a microbiological point of view: sodium hypochlorite 5% (Niclor Ogna, Milan) and a new generation irrigant based on chlorhexidine gluconate and cetrimide (Cetrexidine VEBAS S. Giuliano Milanese-MI). METHODS: The experiments were performed on a series of obligatory anaerobic bacteria which are most frequently found in the endodontium, all belonging to the international collection "American Type Culture Collection" (ATCC) and supplied by Dasit SpA, Cornaredo (MI). The following bacterial strains were used in the experiment: Actinimyces odontolyticus ATCC 17929, Fusobacterium nucleatum ATCC 25586, Prevotella melanginogenica ATCC 25845, Porphyromonas gingivalis ATCC 33277. The working concentration (CFU/ml) was defined as 0.5 McFarland which corresponds to a concentration of microorganisms equivalent to approx. 1.5 x 10(3) bacteria. Each irrigant was kept in contact with the bacterial species used for this experiment for 10', 20', 30'. RESULTS: The results obtained confirm the bactericidal efficacy of both irrigants used, even after a short contact time. CONCLUSIONS: This does not mean that all irrigants are the same and/or promise the same results. This was a microbiological study, but in practice it is important to bear in mind other variables, such as contact time. Moreover, in order to increase the probability of endodontic treatment, root canal irrigants are also required to satisfy other criteria: biocompatibility, scarce toxicity, high proteolytic power.

Anti-Bacterial Agents↗

PubMed1997

[Epidemiologic evaluation of dental and periodontal disorders in a sample of children active in sports].

BACKGROUND: Caries and paradontal diseases occupy an important position among the various diseases of the organism. The spread of these pathologies entails consequences of an aesthetic, functional and economic nature. The aim of this study was to evaluate the oral health conditions of an age-matched and sex-matched sample population with a uniform socioeconomic background all of whom played sports. MATERIALS AND METHODS: The age groups taken into consideration are those specified by the WHO: 8-9 years old and 12-13 years old. A total of 684 children were examined within the framework of medical checkups for fitness to play sports. The epidemiological indices specified by the WHO were used to assess oral health conditions: dmf-t; DMF-T; plaque index (PLI) and paradontal index of need for paradontal treatment in community (CPITN). RESULTS: By comparing the results of this study with the targets set by the WHO for the year 2000 and with those of other studies it was seen that higher values were recorded. CONCLUSIONS: This discrepancy may probably be correlated to the marked consumption of super-calorific substances during the day by children playing sports.

Adolescent↗

PubMedDate not supplied

Risk/prevention indicators for the prevalence of dental caries in schoolchildren: results from the Italian OHSAR Survey.

The Italian Oral Health of Schoolchildren of the Abruzzo Region (OHSAR) Survey was designed to assess indicators associated with the prevalence of caries in both the primary and permanent dentitions in the same schoolchildren, and it comprised a representative sample of 5,938 7-, 9- and 11-year-old schoolchildren from three provinces within the region of Abruzzo, Italy, a low fluoride concentration area. Gender, age, geographic location, socioeconomic level, dietary and oral hygiene habits, and the use of F supplements were all considered as indicators. The subsequent multivariate analyses showed that the socioeconomic level, snack consumption frequency, consumption of sweets and the use of F supplements were mostly associated with caries prevalence in both dentitions. Other indicators, such as gender, age, geographic location, between-meal snack consumption frequency, consumption of sweet drinks, toothbrushing frequency and onset of regular toothbrushing habits also showed some significant associations with dental caries across the age groups and/or dentitions. Of interest, the consumption of commercial bottled mineral water was also seen to be a preventive indicator for dental caries of the primary dentition, particularly in the 7-year-old group. The consumption of sweet snacks, use of interdental floss and kind of toothbrush mainly used (manual or electric) did not show any relevant association with the outcomes. The strong effect of the geographic location, socioeconomical level and the preventive effects of commercial bottled mineral water are worth further investigation.

Analysis of Variance↗

PubMedDate not supplied

Residual and inflammatory radicular cysts. Clinical and pathological aspects of 2 cases.

Inflammatory odontogenic cysts include radicular cysts and its etiological variance, residual cysts. Among these lesions, the radicular cyst is the most frequent. It is caused by the growth of remnants of Malassez cells involved in the development of the dental organ. Clinically, radicular cysts are difficult to diagnose. Histologic diagnosis is of primary importance in order to definitely discriminate the different kinds of periapical lesions. In this paper, the clinical, radiographic, etio-physio-pathological and microscopic features of these pathological formations are described. A case of a large radicular cyst and a case of residual cyst are reported and the surgical treatment and histologic differential diagnosis are presented.

Adult↗

PubMedDate not supplied

[Comparative study of the effects of rotating instruments on the dental surface].

This study analyses the relationship between the use of rotating instruments, the production of a smear layer and the presence of alterations to enamel microstructures. The rotating instruments used were carbide (8-12 blade) and diamond tipped (30-15 m) cutters. Cavities were made in extracted teeth. Subsequently, half the sample was analysed using the rugosimeter before and after the application of ortophosphoric acid at 35% for 15 and the other half suing a Scansion Electronic microscope (SEM). The results obtained showed on the one hand that carbide cutters leave a smoother surfacer than diamond tipped cutters, and on the other that the smear layer is eliminated better by carbide cutters compared to diamond tipped cutters. Moreover, there are no major traumatic-type alterations at the level of the enamel affecting the microstructure after the use of carbide cutters.

Dental Cavity Preparation↗

PubMedDate not supplied

[The evaluation of the clinical efficacy and tolerance of azithromycin in odontostomatological infections].

BACKGROUND: Common oral bacteria are involved in the etiology of odontostomatological infections and there is a prevalence of Gram negative anaerobic microorganisms that are increasingly often found to be resistant to common beta-lactamases. In the light of this phenomenon, the use of beta-lactamases has been replaced by macrolides. The development of azithromycin, which is active against anaerobes and characterised by a wider spectrum of action against Gram negative bacteria, has opened new horizons in the therapeutic approach to odontostomatological infections. AIMS: The aim of the study was to evaluate the clinical efficacy and the tolerability of azithromycin in odontostomatological infections. The study was performed using an open test method, without a comparative drug. METHODS: One hundred patients, including 51 males and 49 females aged between 18 and 64 years old, were included in the study. These patients showed clinical and radiographic symptoms of acute apical periodontitis, periodontal abscess, or third molar dysodontiasis. They were divided into three groups. The drug protocol used was 500 mg/day for three days. The efficacy of the antibiotic was assessed one week after the start of treatment by evaluating the evolution of the pathology on the basis of subjective symptoms (pain) and objective signs (reddening, swelling, basal temperature). A progressive system was used to quantify the clinical findings using an arbitrary score from 0 to 3. The tolerability of treatment was evaluated by recording any signs observed in the patients' data records. RESULTS: The initial mean score for painful symptoms passed from 2.88 to 0.34. The initial mean score for the reddening parameter also fell from 2.3 to 0.34. The same results were found for the reddening sign which presented a mean value of 2.1 at the start of treatment and 0.38 at the end. The 8 patients who presented fever also showed a remission. The overall incidence of side effects was 8%. The side effects affected the gastrointestinal tract. CONCLUSIONS: From an analysis of these results it can be affirmed that azithromycin achieved good therapeutic results in odontostomatological infections in terms of both efficacy and tolerability.

Adolescent↗

PubMedDate not supplied

[Amalgam tattooing. Report of a case].

The authors describe a case of amalgam tatooing which was referred to their attention. Based on a careful revision of the literature on this pathology they describe the clinical aspects, localisation and etiopathogenesis, focusing in particular on the importance of histological analysis, the only means of distinguishing amalgam tatooing from a highly aggressive lesion such as melanoma.

Adult↗