Treating Nerve Injury after Endodontic Microsurgery Using Laser Photobiomodulation: A Report of 2 Cases.

The purpose of this case report was to inform dentists and dental specialists about a noninvasive, viable treatment option that could aid in the recovery of patients who have experienced iatrogenic nerve injuries. Nerve injury is an inherent risk of many dental procedures and a complication that can negatively impact a patient's quality of life and activities of daily living. Managing neural injuries presents a challenge for clinicians because there are no standard protocols reported in the literature. Although spontaneous healing of these injuries can occur, the duration and degree of healing can vary greatly between individuals. Photobiomodulation (PBM) therapy is used as an adjunct in medicine for functional nerve recovery. Once target tissues are illuminated with a low-level laser during PBM, the light energy is absorbed by the mitochondria causing adenosine triphosphate production, modulation of reactive oxygen species, and the release of nitric oxide. These cellular changes explain why PBM has been shown to aid in cell repair, vasodilation, a reduction in inflammation, accelerated healing, and an improvement in postoperative pain. This case report presents 2 patients with neurosensory alterations after endodontic microsurgery with a significant improvement in their condition after PBM treatment using a 940-nm diode laser.

Cytotoxicity Analysis of Human Dental Pulp Stem Cells After Silver Diamine Fluoride Application.

Purpose: The purpose of this study was to evaluate the cytotoxicity of silver diamine fluoride (SDF) to human dental pulp stem cells (hDPSC). Methods: hDPSC were exposed to dilutions of 38 percent SDF ( 10-3, 10-4, and 10-5) and incubated for 24 hours. Cell viability was assessed with colorimetric detection assay at 24 hours. Fresh media was used as a negative control, and 0.1% sodium dodecyl sulfate was used as a positive control. Three independent experiments were performed in triplicate. Cell viability data were analyzed using analysis of variance and Tukey's multiple comparison test. Results: Cells exposed to dilution of 38 percent SDF 10-3 had an average cell viability of 17.0±3.5 (standard deviation) percent. Cells exposed to SDF 10-4 and 10-5 had an average cell viability of 101±2.5 percent and 94±4.4 percent, respectively. Dilution of 10-3 had significantly lower cell viability than the negative control (P<0.001). Dilution of 10-4 and 10-5 SDF had significantly higher cell viability than the positive control (P<0.001) and cells treated with a dilution of 10-3 (P<0.001). Conclusions: Thirty-eight percent silver diamine fluoride was cytotoxic to human dental pulp stem cells at a dilution of 10-3, but not at 10-4 and 10-5. In light of the cytotoxicity of SDF to hDPSC, this in vitro study supports the concern that exposure of the full concentration of 38 percent SDF to the pulp should be avoided.

Effect of surface preparation and light curing on penetration of silver particles from 38% silver diamine fluoride in dentin of primary teeth: An in vitro evaluation.

PURPOSE: To evaluate the effect of light cure, as well as various dentin surface treatment approaches, on the penetration depth of silver precipitating from 38% silver diamine fluoride into primary dentin tubules. METHODS: The occlusal dentin surfaces of 42 non-carious primary molars were exposed and then sectioned into halves bucco-lingually. The halves from each tooth pair were randomly split in two mega-groups, and each mega-group was divided randomly as follows into six experimental groups: prepared by either carbide bur (G1, G2), ceramic bur (G3, G4), or erbium laser (G5, G6). SDF was then applied to all prepared surfaces, and finally even-numbered groups (G2, G4, G6) were light cured. One mega-group was assigned to quantitative evaluation of silver penetration depth along the axial wall, and the other mega-group was reserved for qualitative observation of relative silver distribution on the occlusal surface, both via scanning electron microscope. RESULTS: No significant difference was observed in silver penetration depth between light cure and non-light cure groups (P= 0.8908). There was a statistically significant association between tooth preparation method and depth of silver penetration (P< 0.000001); laser-treated groups had significantly deeper silver penetration (1,148.9 µm G5, 1160.4 µm G6) than carbide bur (P< 0.05; 184.7 µm G1, 301.8 µm G2) or ceramic bur (P< 0.05; 184.1 µm G3, 131.0 µm G4) groups. A significant difference (P< 0.05) was noted in percentage occlusal surface coverage of particles between laser (51.4% G5, 35.8% G6) and carbide groups (21.1% G1, 19.3% G2). Light cure had no significant effect on the depth of silver penetration from 38% SDF in the dentin of primary teeth. Laser preparation resulted in deeper silver penetration than carbide or ceramic bur. CLINICAL SIGNIFICANCE: Exposure of 38% silver diamine fluoride-treated dentin to light cure did not affect the depth of penetration of silver particles into the dentin tubules of primary teeth. Rather, tooth preparation approaches that reduce the smear layer, like laser ablation, resulted in the deepest penetration of silver into the tubules. Clinical application of these findings will depend on scenario and treatment aim.

Impact of simulated patients on students' self-assessment of competency in practice of geriatric dentistry.

PURPOSE: The evaluation of the effectiveness of simulation training in dentistry has previously been focused primarily on psychomotor hand skills. This study explored the impact of simulated patient (SP) encounters in simulation on students' self-assessment of competency in their clinical and communication abilities with geriatric patients. METHODS: Students from 2 cohorts were recruited for this study. Cohort 1 (n = 30) participated in the standard curriculum with no simulation training and served as the control group. Cohort 2 (n = 34) participated in a SP experience, simulating the initial stages of a care visit for 2 nursing home patients. Students' perceptions of competency to perform these clinical and communication tasks were assessed. A group debriefing session was held 5 weeks post-simulation where Cohort 2 completed a student feedback form. RESULTS: A statistically significant change (P < 0.00001) was noted for both cohorts in their self-reported competence to perform clinical tasks following exposure to an independent clinical experience. In addition to this gain, individuals in Cohort 2 demonstrated improvements following simulation and expressed different responses of impact to questions related to treatment, pharmacology, and managing a complex medical history. CONCLUSIONS: This study suggests that simulation of patient interactions using SPs can strengthen students' self-assessment of competency in their abilities, leading to more genuine interactions with actual patients. These findings will help inform the design of future SP encounters as a component of an evolving humanistic curriculum.

Grading Class I Preparations in Preclinical Dental Education: E4D Compare Software vs. the Traditional Standard.

The aim of this study was to compare the effectiveness of a novel assessment software system with the traditional grading protocol used in the University of Texas School of Dentistry at Houston operative dentistry preclinical curriculum. In the study, conducted in 2016, 98 Class I preparations were evaluated both traditionally and digitally by two teams of calibrated preclinical faculty members (two evaluators for each team). Scores from each faculty pair were averaged for the traditional and the digital grading systems, and the scores for the two grading systems were compared. The analysis found no significant difference between the two grading systems with respect to isthmus width (p=0.073) and remaining marginal ridge (p=0.5841), but there was a significant difference with respect to pulpal floor depth assessment (p<0.0001). The data suggested that both grading techniques can be used with repeatable confidence for two out of three grading criteria: isthmus width and remaining marginal ridge. In addition, the software offers a self-assessment tool for students to perfect their psychomotor skills while promoting independence and immediate feedback.

Impact of Technique-Specific Operative Videos on First-Year Dental Students' Performance of Restorative Procedures.

The aim of this study was to examine the impact of psychomotor operative video demonstrations on first-year dental students who are performing specific procedures for the first time in a preclinical setting. The class was randomly divided into two groups, and three restorative procedures were selected. On the date on which each procedure was to be performed in the preclinical laboratory for the first time, one group (experimental, n=50) was shown a technique video for that specific procedure immediately before commencing the exercise; the control cohort (n=50) did not view the video. Technical performance on procedures was evaluated by students and two calibrated and blinded examiners. The students' perceptions of the experience were also collected in a survey. All first-year students participated in the study, for a 100% response rate. A Mann-Whitney U test did not show any group differences in technical performance (mean values on preparation: 77.1 vs. 77.8; amalgam: 82.7 vs. 82.8; composite: 79.7 vs. 78.0). A Spearman rho test revealed a significantly higher correlation in 13 out of 25 evaluation categories between student self-assessment and blinded examiner assessment for the experimental group. A chi-square test of questionnaire responses revealed a positive student perception of administering these videos for the preparation (X(2)=4.8, p<0.03), the amalgam restoration (X(2)=12.4, p<0.001), and the composite restoration (X(2)=11.3, p<0.001). The psychomotor video demonstrations did not immediately improve student performance on preclinical operative procedures, but they were well received by students and augmented self-assessment ability. These findings suggest that videos can be a useful teaching aid in a preclinical environment, especially regarding comprehension of concepts.

Is a drill-less dental filling possible?

Dental caries, a bacterial process that results in the acidic destruction of tooth structure, has historically been managed by the mechanical excavation of diseased tooth structure and then restoration with a synthetic material. The mechanical excavation of the infected site is most commonly achieved by a dental handpiece, or "drill"; this handpiece may induce stress and anxiety in many patients. Alternatively, a drill-less filling will involve the utilization of silver diamine fluoride (38%) to arrest and prevent dental caries, followed by restoration with a bonded filling material to achieve adequate seal at the lesion margins. This is a minimally invasive procedure that addresses both microbial and mechanical issues posed by dental caries.