Faculty Bibliography

A COMMENTARY ON/UNASSIGNED:Lucchese A, Marcolina M, Mancini N et al. A comparison of the alterations of oral microbiome with fixed orthodontic therapy and clear aligners: a systematic review. J Oral Microbiol 2025; 17: 2372751. DATA SOURCES/METHODS:The review searched multiple electronic databases (PubMed, Cochrane Library, Embase, Web of Science, Scopus, Ovid, Dentistry and Oral Sciences Source) and gray literature (OpenGray) up to May 30, 2023. STUDY SELECTION/METHODS:The selection of the studies was processed according to PRISMA guidelines. Two reviewers independently screened titles and abstracts, with disagreements resolved by a third reviewer. Full-text articles were then assessed for eligibility based on pre-defined inclusion/exclusion criteria (RCTs, nRCTs, cohort studies; at least two time points for analysis; minimum 10 patients; clear aligners vs. fixed appliances or comparison between them; patients with good systemic health not taking medications). DATA EXTRACTION AND SYNTHESIS/METHODS:Data extraction from the included studies was carried out by two reviewers in consultation with a third reviewer to define the variables for extraction and resolve any disagreements. Extracted data included study characteristics (author, year, design, sample size, patient age), intervention details, sample collection methods (saliva, plaque), microbial analysis methods (16S rRNA sequencing, PCR, BANA test), and microbiological outcomes. A qualitative synthesis was performed due to the heterogeneity of the included studies, precluding meta-analysis. RESULTS:A total of 484 articles were identified, with 9 studies that met the inclusion and exclusion criteria: eight non-randomized controlled trials and one randomized controlled trial. Sample sizes ranged from 10 to 77 participants. Various microbial analysis methods were employed, including 16S rRNA gene sequencing (5 studies), PCR (3 studies), and the BANA test (1 study). Following the application of rating scales, 1 article was classified as having a low risk of bias, 6 as having a moderate risk, and 2 as having a serious risk of bias. CONCLUSIONS:The review suggests that clear aligners may be associated with a less detrimental impact on the oral microbiome compared to fixed appliances, possibly due to improved oral hygiene. Both therapies alter the oral microbiome; however, the changes caused by aligners are more conducive to better oral health compared to fixed appliances.

OBJECTIVE:Extended reality (XR) technology using head-mounted devices enables the operator to visu-alise anatomical structures. We aimed to investigate student perceptions regarding applying XR simu-lation for transferring endodontic educational information between a lecturer in Japan and students in Saudi Arabia. METHODS:In this study, the students engaged with an XR simulation system and viewed teeth in virtual reality (VR). Pictures of dental anatomy were shown in the VR space, allowing participants to manipulate them. Then, the participants viewed a patient-specific three-dimensional printed model and three-dimensional root canal access guide in a second VR area. Before the sessions, the students completed a questionnaire on demograph-ic data and information concerning their VR experience. After the sessions, they completed a questionnaire evaluating the XR simulation system. The questionnaire included questions on dental anatomy, root canal access, usability, emotional impression, and data transfer. RESULTS:Eleven 5th-year dental students, comprising six male and five female students, were enrolled; three of them had previous VR experience, whereas eight did not. The highest levels of satisfaction were noted in the tooth anatomy (4.6+-0.4) and emotional impression (4.5+-0.5) domains, whereas the lowest level was noted in the data transmission domain (3.5+-0.9). Female participants and those without previous VR experience reported higher satisfaction levels across questionnaire domains compared to male participants and those with previous VR experience. CONCLUSION/CONCLUSIONS:XR can be successfully used in dental education and integrated into online lectures. Restrictions on education caused by health crises can be averted by using XR. Further, fifth-generation networks can offer better data transmission than wireless fidelity.

OBJECTIVE:For a successful root canal therapy, it is necessary to locate all the canals debride and seal them with an inert filling material. The clinician must be aware of the internal morphology and variations in a permanent tooth. Mandibular first molars are widely studied to identify variations in the anatomy of the pulp space. In this study, the primary objective was to measure the distance between the mesiobuccal (MB) and mesiolingual (ML) canals in patients with and without a middle mesial canal (MMC) using cone-beam computed tomography (CBCT). The secondary objectives were to assess the tapering degree of the mesial root and to measure the dentinal thickness in relation to the danger-zone area in patients with and without an MMC. MATERIALS AND METHODS:A total of 200 CBCT scans were evaluated for the presence of an MMC. Two observers performed the observations, and the results obtained were subject to statistical analyses. RESULTS:The results revealed the prevalence of MMC was 5%. The average distance between the MB and ML canals was higher when there was an MMC [M(SD) = 3.61 (0.6) vs. 2.69 (0.66)]. However, there were no differences between the groups in the distance to the danger-zone area and the tapering degree of the mesial root. On CBCT images, the MMC was clearly visible 3 mm apical to the level of the cementoenamel junction; beyond 3 mm, the MMC could not be traced. CONCLUSIONS:Based upon the results of this study, the average distance between the MB and ML canals was higher when there was an MMC. A lesser degree of taper would be preferred to prepare the MMC than to prepare the other canals. It is recommended that careful examination of the canal 3 mm apical to the cementoenamel junction should be carried out when attempting to detect an MMC.

BACKGROUND AND AIM: Many studies have examined the nature of tissue formed in the canals of immature necrotic teeth, following revascularization in animals and humans. While speculations have been made that regeneration of the pulp tissue might take place in the canal, the tissue has been found to be cementum-like, bone-like, and periodontal ligament-like. The purpose of this study was to histologically examine the tissue in the root canals in immature dog teeth that had been artificially infected and then revascularized. METHODS: Two 4- to 5-month-old mongrel dogs with immature teeth were used in the study. In one dog, four maxillary and four mandibular anterior teeth, and in another dog, four maxillary and five mandibular anterior teeth were used in the experiment. Pulp infection was artificially induced in the immature teeth. Revascularization was performed on all teeth by disinfecting the root canals with sodium hypochlorite irrigation and triple antibiotic intracanal dressing, completed with induction of intracanal bleeding, and sealed with an MTA plug. The access cavity was restored with silver amalgam. The animals were sacrificed 3 months after revascularization procedures. The revascularized teeth and surrounding periodontal tissues were removed and prepared for histological examination. RESULTS: Besides cementum-like, bone-like, and periodontal ligament-like tissues formed in the canals, residual remaining pulp tissue was observed in two revascularized teeth. In four teeth, ingrowth of alveolar bone into the canals was seen; presence of bone in the root canals has the potential for ankylosis. CONCLUSIONS: Within the limitation of this study, it can be concluded that residual pulp tissue can remain in the canals after revascularization procedures of immature teeth with artificially induced pulp infection. This can lead to the misinterpretation that true pulpal regeneration has occurred. Ingrowth of apical bone into the root canals undergoing revascularization can interfere with normal tooth eruption if ankylosis occurs.