Combining amino amide salts in mucoadhesive films enhances needle-free buccal anesthesia in adults.

Needle-phobia is usually a great concern in dentistry, and the replacement of painful injections by patient-friendly needle-free topical formulations would bring several advantages in dental practice worldwide. In this pursuit, the effects of combining prilocaine hydrochloride (PCL) and lidocaine hydrochloride (LCL) in different proportions in mucoadhesive films on their in vitro permeation and retention through porcine esophageal mucosa was studied. Complementarily, the permeation and retention of isolated LCL was investigated. The in vitro model used for evaluating buccal anesthetic penetration and retention in buccal epithelium was validated. In addition, the feasibility of a novel in vivo model to evaluate the painful sensation due to puncture "needle-shaped" gum jaw of adults at shallow and deep levels was demonstrated. The in vivo clinical survey revealed the efficiency of the films, which had onset of anesthesia at 5min, peak of anesthetic effect within 15 and 25min and anesthesia duration of 50min after being placed in maxillary sites. The in vitro drug flux, permeability coefficient and retention in the epithelium significantly correlated with in vivo onset, peak and extent of shallow and deep anesthetic effect. At shallow level, the permeation of LCL has shown to be closely related to the onset of anesthesia, while the penetration of PCL has a significant impact in the peak of anesthetic effect. Concerning the deep level, the penetration of PCL is required to attain the onset of anesthetic effect. The total amount of drug retained in the epithelium showed to modulate the extent of both shallow and deep anesthesia. Thus, the combination of LCL and PCL in mucoadhesive films may offer dentists and their patients a safe improvement for pain management during dental procedures.

Different sealing materials preventing the microbial leakage into the screw-retained implant restorations: an in vitro analysis by DNA checkerboard hybridization.

OBJECTIVES: The aim of this controlled in vitro study was to identify and quantify up to 38 microbial species penetrating through the screw-retained implant prostheses with different sealing materials. MATERIAL AND METHODS: Sixty morse cone implants were restored with single-unit screw-retained prostheses. All the components were randomly divided into five groups (n = 12) according to the proposed materials: (1) polytetrafluoroethylene tape+composite resin; (2) polytetrafluoroethylene tape+gutta-percha; (3) polytetrafluoroethylene tape+light-polymerized provisional composite; (4) cotton pellet+gutta-percha; and (5) cotton pellet+light-polymerized provisional composite. Human saliva was used as contaminant media, and DNA checkerboard hybridization was used to identify and quantify microbial species. RESULTS: Microbial leakage was observed in all groups: M. salivarium, S. pasteuri, P. nigrescens, and P. melaninogenica were the species presenting the highest values of genome count, prevalence, and proportion within the groups. The total microbial mean counts (×105 , ±SD) were as follows: Group 1 (2.81 ± 0.38), Group 2 (3.41 ± 0.38), Group 3 (6.02 ± 1.48), Group 4 (6.40 ± 1.42), and Group 5 (17.45 ± 1.67). Group 5 showed the higher microbial counts (P < 0.001). CONCLUSIONS: Moderate to high counts of pathogenic/nonpathogenic species were detected in the inner parts of implants from all groups. The lowest values of microbial counts were recorded for polytetrafluoroethylene tape associated with composite resin or gutta-percha; cotton pellet associated with light-polymerized provisional composite presented the highest microbial counts.

Effectiveness of three antimicrobial mouthrinses on the disinfection of toothbrushes stored in closed containers: a randomized clinical investigation by DNA Checkerboard and Culture.

OBJECTIVES: The aim of this in vivo study was to evaluate the efficacy of three antimicrobial solutions on the disinfection of toothbrushes after storage in closed containers. MATERIALS AND METHODS: Sixteen healthy subjects were enrolled in this randomized cross-over clinical investigation. The study was conducted in four phases, in which mouthrinses (chlorhexidine gluconate-based or cetilpiridinium-based) and sterile tap water (control group) were used to individually store used toothbrushes in closed containers during 7 days of toothbrushing. Five toothbrushes were used as negative control for bacterial colonisation before contact with oral cavity. Conventional culture and DNA Checkerboard hybridization were used to detect bacterial contamination on the toothbrushes. Subsequently, the number of bacterial species on the bristles was estimated by the DNA Checkerboard method. RESULTS: One toothbrush presented bacterial contamination in the negative control test. Both culture and DNA Checkerboard showed positive signals of bacterial contamination in the toothbrushes with no differences in the frequency of detection. The control group showed higher total bacterial counts when compared with the mouthrinse groups. Porphyromonas gingivalis had the highest bacterial count followed by Parvimonas micra. CONCLUSION: Culture and DNA Checkerboard showed positive signals of bacterial contamination. Mouthrinses that contains 0.12% of chlorhexidine gluconate were more effective in reducing bacterial colonisation on the toothbrushes.

Morse taper implants at different bone levels: a finite element analysis of stress distribution

Aim: To explore the biomechanical effects of the different implantation bone levels of Morse taper implants, employing a finite element analysis (FEA). Methods: Dental implants (TitamaxCM) with 4x13 mm and 4x11 mm, and their respective abutments with 3.5 mm height, simulating a screwed premolar metal-ceramic crown, had their design performed using the software AnsysWorkbench10.0. They were positioned in bone blocks, covered by 2.5 mm thickness of mucosa. The cortical bone was designed with 1.5 mm thickness and the trabecular bone completed the bone block. Four groups were formed: group 11CBL (11 mm implant length on cortical bonelevel), group 11TBL (11 mm implant length on trabecular bone level), group 13CBL (13mm implant length on cortical bone level) and group 13TBL (13 mm implant length on trabecular bonelevel). Oblique 200 N loads were applied. Von Mises equivalent stresses in cortical and trabecular bones were evaluated with the same design program. Results: The results were shown qualitatively and quantitatively by standard scales for each type of bone. By the results obtained, it can be suggested that positioning the implant completely in trabecular bone brings harm with respect to the generated stresses. Its implantation in the cortical bone has advantages with respect to better anchoring and locking, reflecting a better dissipation of the stresses along the implant/bone interfaces. In addition, the search for anchoring the implant in its apical region in cortical bone is of great value to improve stabilization and consequently better stress distribution.Conclusions: The implant position slightly below the bone in relation to the bone crest brings advantages as the best long-term predictability with respect to the expected neck bone loss.

Problemas na junção implante/prótese: uma alternativa para resolução do caso / Problems at the implant/prosthesis junction: an alternative for solving the case

A Implantodontia vem se destacando entre as diversas áreas da Odontologia moderna. As possibilidades de tratamento envolvendo os implantes dentários têm facilitado e ampliado a gama de opções ao cirurgião dentista. No entanto, a proposta de tratamento envolvendo reabilitação sobre implantes traz consigo problemas a serem solucionados, já que tal tratamento também é passível de intercorrências. A curva de aprendizagem com o emprego da Implantodontia deve ser respeitada, já que tanto na fase cirúrgica quanto na fase protética, existem critérios a serem respeitados para um bom prognóstico do tratamento. Além disso, quando surgem as intercorrências é imprescindível o preparo e conhecimento do profissional em questão. O presente caso clínico relata uma reabilitação unitária sobre implante, a qual necessitou ser realizada fora dos padrões normais da Implantodontia, já que foi constatada deformação na plataforma hexagonal do mesmo. É possível que tal ocorrência tenha sido causada na fase cirúrgica, durante a instalação do implante, devido a um provável torque excessivo, resultando na impossibilidade da adaptação dos componentes protéticos. A resolução do caso ocorreu com a instalação de um núcleo metálico fundido sobre o implante e confecção de prótese metalocerâmica cimentada. Com o presente relato, pode-se notar a importância do conhecimento de conceitos básicos por parte do cirurgião dentista, assim como sua flexibilidade frente às intercorrências do tratamento

The Implantology has become highlighted among the various areas of modern dentistry. The treatment possibilities involving dental implants have facilitated and expanded the range of options to the dentist. However, the treatment involving rehabilitation with implants can bring problems to be solved, as this treatment is also susceptible to complications. Learning curve with the use of implants should be respected, both in the surgical and prosthetic phases, because there are criteria to be met for a good treatment prognosis. Also, when complications occur, it is essential preparation and knowledge of the professional. This case report describes unit rehabilitation with implant, which needed to be performed outside of the normal standards of implant dentistry, as was observed deformation on the hexagonal platform. It is possible that it has been caused during implant installation surgery phase, due to an excessive torque, resulting in the inability to adapt the prosthetic components. The case resolution was with the installation of a cast metal core on the implant and making a metaloceramic cemented prosthesis. With this case report may be noted the importance of knowledge of basic concepts by the dentist, as well as its flexibility in the face of complications of treatment