Evaluation of microbial air quality and aerosol distribution in a large dental clinic.

PURPOSE: To evaluate the microbial air quality during dental clinical procedures in a large clinical setting with increasing patient capacity. METHODS: This was a single-center, observational study design evaluating the microbial air quality and aerosol distribution during normal clinical sessions at 5% (sessions 1 and 2) and at > 50% (session 3) treatment capacity of dental aerosol generating procedures. Sessions 1 and 2 were evaluated on the same day with a 30-minute fallow time between the sessions. Session 3 was evaluated on a separate day. For each session, passive air-sampling technique was performed for three collection periods: baseline, treatment, and post-treatment. Blood agar plates were collected and incubated at 37°C for 48 hours. Colonies were counted using an automatic colony counter. Mean colony forming units (CFU) per plate were converted to CFU/m²/h. RESULTS: Kruskal Wallis test was performed to compare the mean CFU/m²/h between the clinic sessions. Statistically significant differences were observed between sessions 1 and 2 (P< 0.05), but not between sessions 2 and 3 (P> 0.05). Combining all clinical sessions, the mean CFU/m²/h were 977 (baseline), 873 (treatment), and 1,631 (post-treatment) for the collection periods. A decrease-to-increase CFU/m²/h trend was observed from baseline to treatment, and from treatment to post-treatment that was observed for all clinic sessions and was irrespective to treatment capacity. Higher amounts of CFU/m²/h were found near the air exhaust outlets for all three clinic sessions. Microbial aerosol distribution is most likely due to the positions and power levels of the air inlets and outlets, and to a lesser extent with patient treatment capacity. CLINICAL SIGNIFICANCE: Dental clinics should be designed and optimized to minimize the risk of airborne transmissions. The results of this study emphasize the need to evaluate dental clinic ventilation systems.

Management of Root Sensitivity following Socket Shield Technique with Anterior Single Immediate Implant Placement and Provisionalization.

It is challenging for implants in the esthetic zone to maintain the facial soft tissue contour and interimplant papillae. To counteract the inevitable hard and soft tissue changes after tooth extraction, the socket shield technique (SST) has been advocated as means to maintain the facial and/or interproximal osseous and gingival architecture. As SST is a technique-sensitive procedure, various complications related to SST have been reported. This article presents a unique complication after a socket shield procedure and a novel management of the complication.

Enhancement of peripheral seal of medical face masks using a 3-dimensional-printed custom frame.

BACKGROUND: During the COVID-19 pandemic, American Society for Testing and Materials level 3 and level 2 medical face masks (MFMs) have been used for most health care workers and even for the first responders owing to a shortage of N95 respirators. However, the MFMs lack effective peripheral seal, leading to concerns about their adequacy to block aerosol exposure for proper protection. The purpose of this study was to evaluate the peripheral seal of level 3 and level 2 MFMs with a 3-dimensional (3D-) printed custom frame. METHODS: Level 3 and level 2 MFMs were tested on 10 participants with and without a 3D-printed custom frame; the efficiency of mask peripheral seal was determined by means of quantitative fit testing using a PortaCount Fit Tester based on ambient aerosol condensation nuclei counter protocol. RESULTS: The 3D-printed custom frame significantly improved the peripheral seal of both level 3 and level 2 MFMs compared with the masks alone (P < .001). In addition, both level 3 and level 2 MFMs with the 3D-printed custom frame met the quantitative fit testing standard specified for N95 respirators. PRACTICAL IMPLICATIONS: The 3D-printed custom frame over level 3 and level 2 MFMs can offer enhanced peripheral reduction of aerosols when using collapsible masks. With the shortage of N95 respirators, using the 3D-printed custom frame over a level 3 or level 2 MFM is considered a practical alternative to dental professionals.

A clinical investigation of dental evacuation systems in reducing aerosols.

BACKGROUND: The route of transmission of severe acute respiratory syndrome coronavirus 2 has challenged dentistry to improve the safety for patients and the dental team during various treatment procedures. The purpose of this study was to evaluate and compare the effectiveness of dental evacuation systems in reducing aerosols during oral prophylactic procedures in a large clinical setting. METHODS: This was a single-center, controlled clinical trial using a split-mouth design. A total of 93 student participants were recruited according to the inclusion and exclusion criteria. Aerosol samples were collected on blood agar plates that were placed around the clinic at 4 treatment periods: baseline, high-volume evacuation (HVE), combination (HVE and intraoral suction device), and posttreatment. Student operators were randomized to perform oral prophylaxis using ultrasonic scalers on 1 side of the mouth, using only HVE suction for the HVE treatment period and then with the addition of an intraoral suction device for the combination treatment period. Agar plates were collected after each period and incubated at 37 °C for 48 hours. Colony-forming unit (CFU) counts were determined using an automatic colony counter. RESULTS: The use of a combination of devices resulted in significant reductions in CFUs compared with the use of the intraoral suction device alone (P < .001). The highest amounts of CFUs were found in the operating zone and on patients during both HVE and combination treatment periods. CONCLUSIONS: Within limitations of this study, the authors found significant reductions in the amount of microbial aerosols when both HVE and an intraoral suction device were used. PRACTICAL IMPLICATIONS: The combination of HVE and intraoral suction devices significantly decreases microbial aerosols during oral prophylaxis procedures.

A Retrospective Comparison of Outcome in Patients Who Received Both Nonsurgical Root Canal Treatment and Single-tooth Implants.

INTRODUCTION: Currently, no study has compared the outcome of nonsurgical root canal treatment (NSRCT) and single-tooth implants (STIs) provided to the same patient. The purpose of this study was to determine if the survival outcome of the 2 treatment modalities is different. METHODS: The medical/dental records of 3671 patients with at least 1 STI and 1 NSRCT were reviewed. One hundred seventy patients with at least a 5-year follow-up were included. The survival outcome of NSRCT and STI and related factors were evaluated. RESULTS: Both treatments had a 95% survival rate with a mean 7.5-year follow-up. Most preoperative and postoperative factors involved in both procedures had no significant effect on the treatment outcomes. The number of adjunct and additional treatments, the number of appointments, the elapsed time before the final restoration, the number of prescribed medications, and the cost of the treatment were significantly higher for STI in comparison with NSRCT. CONCLUSIONS: Both NSRCT and STI are highly successful treatments. Compromised teeth that could otherwise be saved by NSRCTs and deemed restorable should not routinely be treatment planned for STI.

Effect of apex size on the leakage of gutta-percha and sealer-filled root canals.

OBJECTIVES: There are no data comparing coronal leakage of teeth prepared to different apical sizes and obturated with gutta-percha and sealer. The aim of this study was to investigate the effect of apical preparation size on the leakage of obturated root canals. Large apical openings are encountered as a result of pulp necrosis in immature teeth, apical resorption, or over-enlargement of the apical foramen. Complete cleaning, shaping, obturation, and apical seal of root canal systems are essential for the success of root canal treatment. METHOD AND MATERIALS: One hundred twenty-five extracted human teeth were divided into groups containing 25 samples each and prepared to apical file sizes 30, 40, 50, 60, and 70. Twenty teeth served as positive and negative controls. Obturation was completed with gutta-percha and sealer via warm vertical compaction. Bacterial leakage was investigated after 112 days using Proteus vulgaris. Data were analyzed via independent-samples Kruskal-Wallis test. RESULTS: The average time for leakage of apical preparation sizes 30, 40, 50, 60, and 70 were 57.5, 52.4, 47.2, 37.5, and 28.4 days, respectively. Significant differences in leakage were observed between apical preparation sizes 70 versus 30, 70 versus 40, 70 versus 50, as well as 60 versus 30. A trend for more leakage occurred when apical preparation sizes exceeded size 60. CONCLUSIONS: Based on these results, it appears leakage of gutta-percha and sealer as obturation materials increases when apical preparation size exceeds 60. Consideration should be given to using sealing materials other than gutta-percha and sealer when the apex size exceeds 60.

Evidence-Based Practice Knowledge, Perceptions, and Behavior: A Multi-Institutional, Cross-Sectional Study of a Population of U.S. Dental Students.

The aim of this study was to help inform faculty and curriculum leaders in academic dental institutions about the knowledge, skills, perceptions, and behavior of an institutionally diverse population of dental students with respect to evidence-based practice (EBP). A survey utilizing the validated Knowledge, Attitudes, Access, and Confidence Evaluation instrument developed by Hendricson et al. was conducted in 2012 with fourth-year dental students at seven geographically dispersed U.S. dental schools. The survey addressed elements of EBP knowledge, attitudes toward EBP, behavior in accessing evidence, and perceptions of competence in statistical analysis. A total of 138 students from the seven schools participated. A slight majority of these students correctly responded to the knowledge of critical appraisal questions. While the students demonstrated positive attitudes about EBP, they did not report high levels of confidence in their critical appraisal skills. The findings also showed that the students accessed various sources of evidence with differing frequencies. The most frequently accessed resources were colleagues, the Internet (excluding Cochrane Database of Systematic Reviews), and textbooks. The results of this study help to identify areas for improvement in EBP education in order to advance dental students' preparation to become evidence-based practitioners.

Survival of Intentionally Replanted Teeth and Implant-supported Single Crowns: A Systematic Review.

INTRODUCTION: Although nonsurgical initial root canal treatment and retreatment have high success rates, periapical disease can remain. The survival rates of 2 surgical procedures, intentionally replanted (IR) teeth and implant-supported single crowns (ISCs), have yet to be compared. The purpose of this systematic review and meta-analysis was to examine the literature and quantify the survival of IR teeth and compare it with that of ISCs. METHODS: Systematic searches were enriched by citation mining. Weighted survival means and 95% confidence intervals (CI) were estimated using a random-effects model and compared. RESULTS: The quality of the IR and ISC articles was only moderate. Data for ISCs were much more plentiful than for IR teeth. Meta-analysis revealed a weighted mean survival of 88% (95% CI, 81%-94%) for IR teeth. Root resorption was reported with a mean prevalence of 11%. The weighted mean survival of ISCs was 97% (95% CI, 96%-98%). The mean survival of ISCs was significantly higher than that of IR teeth (P < .001). A recent study on IR teeth indicated that orthodontic extrusion before intentional replantation improved survival rates. CONCLUSIONS: A systematic review and meta-analysis found that the mean survival of ISCs was significantly higher than IR teeth. However, treatment decisions must be based on a wide variety of treatment and patient-specific parameters. Intentional replantation may have a role when ISC is not practicable. Studies using contemporary treatment and analytic methods should be used to identify and measure intentional replant prognostic and treatment variables.

Clinical implications of the smear layer in endodontics: a review.

It has been recognized for many years that root canal instrumentation produces a smear layer that covers the surfaces of prepared canal walls. This layer contains inorganic and organic substances such as fragments of odontoblastic processes and necrotic debris. There is a lack of agreement regarding the effect of the smear layer on the quality of instrumentation and obturation, but the smear layer itself may be infected and may protect the bacteria within the dentinal tubules. Various methods have been used to remove the smear layer. Conflicting results have been obtained from numerous in vitro studies regarding the significance of the presence or the removal of the smear layer.

Evaluating postdoctoral dental candidates: assessing the need and recommendations for a national qualifying examination.

Increasingly, U.S. dental schools report pass/fail grades and do not rank students. In addition, the Joint Commission on National Dental Examinations will report National Board Dental Examination (NBDE) scores as pass/fail after January 1, 2012. This article discusses how these changes will force postdoctoral dental program directors to modify how they assess candidates and how noncognitive evaluations might enhance those assessments. The authors propose developing a national qualifying examination for postdoctoral dental programs that will measure knowledge, decision making, and noncognitive traits including empathy, self-confidence, integrity, and emotional intelligence. Without NBDE scores, class rank, and GPA as a basis for decision making, a single national qualifying examination would assist postdoctoral programs in selecting high-quality candidates based on knowledge, critical thinking skills, and noncognitive traits.

Outcomes of nonsurgical retreatment and endodontic surgery: a systematic review.

INTRODUCTION: The purpose of this systematic review was to compare the clinical and radiographic outcomes of nonsurgical retreatment with those of endodontic surgery to determine which modality offers more favorable outcomes. METHODS: The study began with targeted electronic searches of MEDLINE, PubMed, and Cochrane databases, followed with exhaustive hand searching and citation mining for all articles reporting clinical and/or radiographic outcomes for at least a mean follow-up of 2 years for these procedures. Pooled and weighted success rates were determined from a meta-analysis of the data abstracted from the articles. RESULTS: A significantly higher success rate was found for endodontic surgery at 2-4 years (77.8%) compared with nonsurgical retreatment for the same follow-up period (70.9%; P < .05). At 4-6 years, however, this relationship was reversed, with nonsurgical retreatment showing a higher success rate of 83.0% compared with 71.8% for endodontic surgery (P < .05). Insufficient numbers of articles were available to make comparisons after 6 years of follow-up period. Endodontic surgery studies showed a statistically significant decrease in success with each increasing follow-up interval (P < .05). The weighted success for 2-4 years was 77.8%, which declined at 4-6 years to 71.8% and further declined at 6+ years to 62.9% (P < .05). Conversely, the nonsurgical retreatment success rates demonstrated a statistically significant increase in weighted success from 2-4 years (70.9%) to 4-6 years (83.0%; P < .05). CONCLUSIONS: On the basis of these results it appears that endodontic surgery offers more favorable initial success, but nonsurgical retreatment offers a more favorable long-term outcome.