Acta odontologica latinoamericana : AOL最新文献

The removal of tissues affected by caries lesions is one of the most frequent procedures in daily dental practice. The aim of this study was to collect information about the habits of members of the academic and non-academic dental community in Argentina regarding the use and conditioning of burs employed in the removal of dentin during the treatment of carious lesions. A 14- item questionnaire was prepared, and once validated in small groups, it was sent to three lists of dental subscribers through the computer services area of the School of Dentistry, University of Buenos Aires, Argentina (FOUBA). By the deadline for receiving responses, which was set as four weeks after the sending date, 294 replies were received. Results: percentage (95%CI): 47.93% (42.18-53.68%) of the respondents were faculty members, of whom 37.24% (31.68-42.81%) claimed to belong to FOUBA. Of the respondents, 26.90% (21.79-32.00%) reported being under 35 years old, 37.59% (32.01-43.16%) 36 to 45 years old, 22.07% (17.30-26.84%) 46 to 55 years and 11.38% (7.72-15.03%) over 55 years. Regarding bur type, 68.07% (62.31%-73.44%) claimed to use round burs to remove carious dentin and 27.72% (22.60%-23.31%) round + others. Regarding rotary speed, 22.07% (17.30-26.84%) use medium speed, 32.76% (27.36-38.16%) use high speed, and 32.76% (27.36-38.16%) use medium + super high. Only 17.93% (13.52- 22.35%) indicated that they know how to quantify the number of times they use their burs, while 50.34% (44.59-56.10%) of the respondents said that they use burs "until they no longer cut", 23.79% (18.89-28.69%) use them 1 to 5 times. 98.27% (96.77-99.77%) said they clean their burs once used. When the answers regarding the use of rubber dam were compared with area of specialization (Chi-square), it was found that faculty members mention the use of burs under rubber dam always or almost always 74.82% (67.60-82.04%) while outside the academic field, 51.01% (42.98-59.03%) of dentists say that they never or almost never do so (p <0.001). Conclusion: Most respondents state that they sterilize their rotary instruments in some way after use. About half of them do not keep track of the number of uses and use burs "until they no longer cut".

The use of correctly designed animal models is a fundamental step prior to clinical trials in humans. Although rats are easy to house and handle, and have molars that resemble those of humans, very few researchers use them as a model for root canal treatment, probably due to their small size and the lack of relevant data necessary to reproduce the model. Our aims were to describe the anatomic and histologic characteristics of the mandibular first molar of the Wistar rat and present a standardised model for its experimental endodontic treatment. Twenty female rats were used. The characteristics of the mesial and distal roots were described histologically and the quality of the results achieved following the treatment protocol presented herein was assessed by means of digital radiographs, micro- CT and histological sections. The age of 55 days was found to be the most adequate for performing this technique, but we consider the interval of 50 to 60 days to be suitable. Both canals are oval, although in opposite planes, and the furcating-facing walls present the minimum dentine thickness. It was essential to become familiar with these aspects in order to decide upon the most appropriate instrumentation and obturation techniques that would enable replication of this model in basic science research.

Severe periodontal disease (SPD) associated with systemic peripheral inflammation, cognitive impairment (CI) and arterial stiffness (AS) has been recognized. The aim of this study was to investigate whether CI and arterial stiffness (AS) occur in cardiovascular disease (CVD) patients with SPD. A crosssectional case-control study included hospitalized patients with CVD. Demographic characteristics, CVD and atherogenic risk factors were recorded. SPD was diagnosed by clinical and radiographic dental examinations. Dental clinical attachment level (CAL) and CAL % were recorded. A Mini-Mental State Examination test (MMSE) assessed cognition, a MMSE score of < 27 was set as the cut-off point of CI; a score ≥ 27 was considered as no CI. Patients were categorized into: MMSE<27 (cases) and MMSE≥27 (controls). AS was evaluated by pulse wave velocity (PWV). Serum VCAM-1 levels were determined in a random sample. Results: This study comprised 91 patients (cases, n=26; 29.6%; controls, n=65, 71.4%); aged 73±8 vs. 73±7 years, respectively (p=0.73), of whom 53.8% and 36.9% respectively, were women; SPD was found to be a risk factor for CI; the presence of SPD increased the risk for MMSE <27 by an average 5.39 times (model 1). PWV was associated with MMSE < 27 in the three models. The risk of having MMSE < 27 increased an average of 2.404-fold for each 1-unit increase in PWV. SPD and AS had significant and independent associations on the risk for development CI. MMSE negatively correlated with CAL% (r=0.69) and PWV (r=0.70). PWV positively correlated with CAL% (r=0.67). Serum VCAM-1 levels were higher in SPD with lower MMSE scores. In conclusion, SPD increases the risk of development of cognitive decline in CVD patients. PWV was directly associated with the risk of cognitive decline. These findings denote a significant opportunity to improve periodontal health in order to avert CI in CVD patients.

Pain control is essential in dental practice, and can be accomplished through various techniques. This study seeks to compare atraumatic and conventional anesthetic techniques, applied during surgeries to remove upper third molars. The endpoints evaluated were pain indices, patient satisfaction and anesthetic efficacy. A random parallel split-mouth clinical trial was conducted with 14 patients. Group A received atraumatic anesthesia without a needle (Comfort-in®) and group B received conventional anesthesia by blocking the posterior superior alveolar nerve (PSAN) and Greater Palatine Nerve (GPN). A Visual Analogue Scale (VAS) was used to assess pain. A significantly (p<0.001) lower perception of pain was observed among individuals who received the atraumatic technique. In 71% of cases, it was necessary to supplement the anesthesia during the procedure. Even considering the need for additional anesthesia, the Comfort-in® technique was more accepted by patients with regard to pain perception than the conventional manual technique.

The aims of the present study were, first, to identify signs of alveolar bone damage in early stages of experimental periodontitis (EP) and, second, to assess its possible prevention by treatment with cannabinoid receptor 2 agonist HU 308. Experimental periodontitis was induced by injections of lipopolysaccharide (LPS) (1mg/ml) in gums surrounding maxillary and mandibular first molar, 3 days per week, and untreated controls were kept for comparison. Then, a 3-week study was conducted including eighteen new rats (six rats per group): 1) controls; 2) experimental periodontitis rats; and 3) experimental periodontitis rats treated daily with HU 308 (500 ng/ml). After euthanasia, alveolar bone loss was assessed by morphometric and histomorphometric techniques, and the content of prostaglandin E2 (PGE2) in gingival tissue was evaluated by radioimmunoassay. The first signs of alveolar bone loss were apparent at 3 weeks of experimental periodontitis (ρ<0.05) in the mandibular first molar, but there was no detectable change at 1 week, leading us to establish 3 weeks as an early stage of experimental periodontitis. Rats subjected to 3-week experimental periodontitis showed less interradicular bone volume, less whole bone perimeter and fewer bone formation areas, and higher periodontal space height, bone resorption areas, number of osteoclasts and gingival content of prostaglandin E2 than controls, while HU 308 prevented, at least partially, the deleterious effects (ρ<0.001). We can conclude that a 3-week term of lipopolysaccharide-induced periodontitis in rats provides a valid model of the early stage of the disease, as emerging damage is observed in bone tissue. Furthermore, harmful effects at 3 weeks could be prevented by local stimulation of cannabinoid receptor 2, before greater damage is produced.