Post-traumatic rehabilitation of anterior teeth with laminates composite veneers in children. Report of two cases.

BACKGROUND: When treating children, a conservative and minimally invasive approach is mandatory. In dental traumas with partial coronal destruction, veneers represent the fastest and most effective method to rehabilitate front teeth of a young patient, since these no- or minimal-preparation restorations were proved to have predictable results without reducing the enamel layer. Indirect additive anterior composite restorations, besides being quick and minimally invasive, have to be considered a good treatment option for rehabilitating children, because they are inexpensive and repairable over time. Current laboratory techniques, associated with a strict clinical protocol, satisfy patients' restorative and aesthetic needs in few appointments and in a short time. CASE REPORT: The cases reported describe the minimally invasive treatment of two lateral incisors with nano-hybrid resin composite veneers after traumatic events. The patient satisfaction and good integration of indirect restorations confirmed the success of this rehabilitation.

Is a new sonic toothbrush more effective in plaque removal than a manual toothbrush?

AIM: Powered or manual toothbrushes are daily-used instrument in the Western area for the control and removal of bacterial biofilm. Among powered-toothbrushes, sonic technology has shown to produce fluid turbulent activity that might assist in plaque removal; however, limited knowledge is available in-vivo. The objectives of this study were to compare the plaque removal efficacy of two different toothbrushes in a population not familiar with sonic technology, and to collect and analyse data regarding oral hygiene habits. The null-hypothesis was that a sonic toothbrush is able to remove a superior amount of plaque compared to the manual type. MATERIALS AND METHODS: Forty young adult patients were enrolled in the study. A single-cohort crossover clinical trial was designed. For each patient, three appointments were scheduled: the first (T0) was used for oral care education and explanations of toothbrushes techniques, for a preliminary professional hygiene session, and for delivery of a questionnaire; at one week (T1), plaque evaluation was performed (Turesky modification of the Quigley and Hein index) at baseline and after asking patients to brush with the randomly selected manual or sonic device. At the last appointment (week 3, T2), the same plaque evaluations of T1 were repeated asking patients to brush with the other toothbrush. Entire mouth indexes were calculated and mean reductions in whole mouth plaque scores were obtained (pre-brushing minus post-brushing values) for the two tested toothbrushes. Multiple ANOVA tests (p = 0.05 ) were used 1) to compare plaque levels between male and female subjects at baseline and post-brushing, regardless the type of toothbrush, and 2) to differentiate between mean reductions in whole mouth plaque scores according to the type of toothbrush (manual versus sonic). The study population was subjected to descriptive statistical analysis; potential relationships between socio-demographic variables and obtained plaque scores were evaluated (Mann-Whitney and Kruskal-Wallis tests). RESULTS: Full-mouth plaque levels were reduced at post-brushing sessions, regardless the device, by approximately 62% (p<0.0001). Mean plaque index reductions for manual and sonic toothbrush were of 1.05 ± 0.22 and 1.19 ± 0.37, respectively. A statistically significant difference was found between the two devices (p = 0.0342). The powered sonic toothbrush removed about 10% more plaque than the manual type. From the collected questionnaire financial data, willingness to pay (WTP) values expressing economic efforts of patients for the purchase of toothbrushes were of Euros 4.83 ± 3.86 and of Euros 54.75 ± 36, for the manual and sonic devices, respectively. CONCLUSION: Within the limitations of the study, in subjects without any previous experience of a similar technology, the single use of the sonic toothbrush showed a significantly greater plaque reduction compared to the manual traditional toothbrush (null-hypothesis accepted).

Treatment of traumatic dental injuries: evaluation of knowledge among Italian dentists.

AIM: The aim of this study was to evaluate the degree of knowledge in the management of different scenarios of dental trauma in a population of Italian dentists. MATERIALS AND METHODS: A closed-ended questionnaire consisting of 5 clinical cases of common traumatic dental injuries was asked to be filled out by dentists in the area of Milan, Italy. A total of 500 questionnaires were collected; after a descriptive analysis of the population, results of correct answers were expressed in frequency distribution and computed in percentages. To examine possible associations between the level of knowledge for each question (number/percentage of correct answers) and independent variables of the population (sex, number of years after graduation, attendance of dental trauma courses, type of clinical activity) appropriate correlation tests were performed (Pearson chi-square, or Fisher's exact; level of significance = 0.05) for identification of statistically significant differences. RESULTS: More than 75% of participants answered correctly to the questions regarding crown fracture and extrusive luxation injuries; only 40% of dentists responded correctly about the duration and type of splinting following avulsion; 60% of participants incorrectly chose immediate invasive therapies (tooth extraction or endodontic procedures) for horizontal middle-root fracture. There was a trend towards slightly better knowledge (in 7 out of 9 questions) for dentists 1) working in hospitals and 2) who had attended a post-graduate course in traumatology. CONCLUSION: The level of knowledge in the group of dentists considered was heterogeneous; problems in the management of traumatic dental injuries were restricted to specific clinical cases and topics.

Second order root control of self-ligating brackets and traditional brackets: a "typodont" study.

AIM: Aim of the study was to evaluate if self-ligating brackets (SLB) and conventional brackets (CB) have the same degree of second order root control in closing extraction spaces. METHODS: Two resin models, left and right sides of an upper arch, with two wells in the premolar area, were used. Wells have been filled with wax and resin premolars with anatomic root structure were placed in them. Resin premolars were bonded with CB and SLB. We performed 20 pairwise runs: CB on one side against SLB on the other side. We tested 0.018 and 0.016x0.022 stainless steel arches. Models were put in warm water to allow teeth to move in the softened wax by the force excerpted by NiTi coils. Root control in the second order was evaluated with the aid of metallic markers on the roots and digital radiographies taken before and after each run. RESULTS: On 0.018 wires CB moved 4.0 mm (SD 1.06 mm), mean root control angle was 14.8° (SD 9.15°), while SLB moved 4.1 mm (SD 1.33 mm), mean angle in the second order was 11.8° (SD 5.01°). On 0.016x0.022 wires CB moved 3.6 mm (SD 1.24 mm), mean angle in the second order was 9.7° (SD 5.48°) while SLB moved 3.4 mm (SD 1.05 mm), mean angle was 10.7° (SD 3.92°). CONCLUSION: It seems that, on typodont, CB and SLB are equally efficient in moving teeth crowns and have the same degree of second order root control, both when 0.018 and 0.016x0.022 stainless steel wires are used.

Esthetics in the edentulous: clinical steps for recovering of maxillary anterior teeth harmony.

Smile designing for edentulous patients has not been much investigated; the selection of artificial teeth is a task that follows multiple consequential steps such as choosing their form, size, material, color and disposition. Even if smile designing is thought to involve some artistic abilities, specific techniques or suggestions have been proposed in the literature to perform each step of the selection of artificial teeth, keeping in mind the importance of consultation and understanding of the patient preferences. This article will focus on the recovering of maxillary anterior teeth harmony in an edentulous patient; a clinical case report will show the rationale process of anterior teeth selection, supported by scientific guidelines found in the literature.

Human erythrocyte delta-aminolevulinate dehydratase inhibition by monosaccharides is not mediated by oxidation of enzyme sulfhydryl groups.

The heme pathway enzyme delta-aminolevulinate dehydratase is a good marker for oxidative stress and metal intoxication. This sulfhydryl enzyme is inhibited in such oxidative pathologies as lead, mercury and aluminum intoxication, exposure to selenium organic species and diabetes. Oxidative stress is a complicating factor in diabetes, inducing non-enzymatic glucose-mediated reactions that change protein structures and impair enzyme functions. We have studied the effects of high glucose, fructose and ribose concentrations on delta-ALA-D activity in vitro. These reducing sugars inhibited delta-ALA-D with efficacies in the order fructose=ribose>glucose. The possible mechanism of glucose inhibition was investigated using lysine, DTT, and t-butylamine. Oxidation of the enzyme's critical sulfhydryl groups was not involved because DTT had no effect. We concluded that high concentrations of reducing sugars or their autoxidation products inhibit delta-ALA-D by a mechanism not related to thiol oxidation. Also, we are not able to demonstrate that the formation of a Schiff base with the critical lysine residue of the enzyme is involved in the inhibition of delta-ALA-D by hexoses.

On the decomposition of stress and strain tensors into spherical and deviatoric parts.

It is well known that Hooke's law for a linearly elastic, isotropic solid may be written in the form of two relations that involve only the spherical or only the deviatoric parts of the tensors of stress and strain. The example of the linearly elastic, transversely isotropic solid is used to show that this decomposition is not, in general, feasible for linearly elastic, anisotropic solids. The discussion is extended to a large class of work-hardening rigid, plastic solids, and it is shown that the considered decomposition can only be achieved for the incompressible solids of this class.