International Journal of Dentistry最新文献

Introduction: It is important to take into account variations in structures related to dental pulp for planning the most adequate endodontic treatment management. The objective of this study was to determine the morphology of roots and canals of maxillary first premolars (MFPs) using cone-beam computed tomography (CBCT). Materials and Methods: This retrospective study included a sample of 392 CBCTs of Peruvian adults proportionally selected by sex, age, and quadrant. One MFP per individual was selected for evaluation by a calibrated evaluator based on the number of roots and canal configuration according to the Vertucci classification (VC; Cohen's κ ≥ 0.834). Pearson's χ ² and Kruskal-Wallis tests were used with a significance level of P < 0.05. Results: Most MFP presented double roots (59.9%) and were VC type IV (52%). Morphology showed a nonsignificant difference by quadrants (P=0.994). A significant positive association was found between the presence of double roots and type IV in men and with older age, while single roots and type I and II were associated with women and younger age (P < 0.05). Double roots were associated with VC type IV (86%) and single roots with types III (34%), II (32%), and I (26%; P < 0.001). Conclusions: MFPs in a Peruvian sample presented a higher frequency of double roots with two separate canals. The morphology of root and canals was associated with age and sex.

Objectives: To evaluate the impact of surface conditioning of titanium, zirconia thickness, and cement type on the final color of zirconia luted to the titanium. Methods: A total of 192 grade 5 titanium specimens with the final dimensions 10 mm × 10 mm × 2 mm were fabricated and subjected to four different surface conditioning including, that is, sandblasting, etching, and anodization. In addition, 192 zirconia specimens with the same dimensions as the titanium specimens but altered thicknesses of 0.7 (n = 96) and 1.0 (n = 96) mm were fabricated using 5Y-TZP zirconia. Color as expressed by L ^∗ (lightness), a ^∗ (red-green axis), and b ^∗ (blue-yellow axis) of titanium and zirconia specimens as well as the joined titanium-zirconia complex, total assembly (Panavia V5 clear, PC; opaque, PO, each n = 96) were determined under standardized conditions using a spectroradiometer (SpectraScan P-650). Color differences were calculated using the ΔE ₀₀ formula. ANOVA supplemented with post hoc Tukey test for group comparisons was compiled to estimate possible effects of titanium conditioning, zirconia thickness, and type of cement used on the final zirconia color (SPSS Ver. 28; α = 0.05). Results: All investigated factors affected the zirconia color of the total assembly (p  < 0.001). Using PO mean values of all groups were still close to baseline colors (ΔE ₀₀ between 5.5 and 6.2). When using PC, the final color was significantly altered, irrespective of the other parameters. Specimens luted with PO appeared lighter, less reddish (a ^∗ was affected predominately by sample thickness), and more bluish, while luting with PC resulted in reduced lightness combined with large shifts along the red and yellow axes. Significance: Color changes of zirconia luted to titanium are primarily affected by the color of the substrate if a translucent cement was used. Vice versa, the application of an opaque cement effectively masked the dark substrate color. Substrate color and choice of cement have to be taken into consideration when performing shade selection.

Objectives: This study aims to evaluate the color-matching ability of OMNICHROMA composite, a single-shade composite, using the CIE L ^∗ a ^∗ b ^∗ system and determining ΔE values. Materials and Methods: In this in vitro study, 30 intact premolar teeth were collected, cleaned, and disinfected with 0.5% thymol solution. The teeth were stored in distilled water at 37°C. A putty index calibrated the color assessment sites on buccal and lingual surfaces. Two cavities were prepared, one with 1.25 mm depth (enamel) and another with 2.25 mm depth (dentin), and restored using OMNICHROMA composite resin. The putty index measured the color of the cured composite, and ΔE between the composite and original tooth color was calculated. Statistical analysis: Data analysis included t-tests, correlation coefficients, and Fisher's exact test (α = 0.05). Results: The mean ΔE was 2.39 in enamel cavities and 2.32 in dentin cavities, both within the clinically acceptable range (<3.3). In enamel cavities, the composite color was darker than the tooth, shifting toward green and blue shades. In dentin cavities, the composite color was lighter than the tooth, with shifts toward green and yellow shades. Color matching was slightly better in dentin cavities, but the difference was not statistically significant (p=0.719). Conclusion: OMNICHROMA composite resin's color matching falls within the clinically acceptable range, unaffected by cavity depth.

Objective: The purpose of this study is to determine the prevalence and features of oral and maxillofacial lesions found in the residents of Al-Qassim region, Saudi Arabia. Methods: A retrospective study was conducted at King Fahad Specialist Hospital, Buraidah, Qassim, KSA. The data for all biopsied oral and maxillofacial lesions were retrieved from January 2014 until August 2022. All patients' data including age, gender, location of the lesion, and histopathologic diagnosis were reviewed and analyzed using IBM SPSS version 23 and Microsoft Excel. Results: A total of 381 oral pathology biopsies for individuals aged 18 and above were included in a descriptive analysis. One hundred ninety five (51.18%) of patients were male, and 186 (48.82%) were female. The site most commonly biopsied was the oral mucosa (26%). The diagnosis was categorized according to the histopathological diagnosis into 13 categories including all pathological lesions in the oral and maxillofacial area. The frequently biopsied category was soft tissue pathological lesion category (26%), second to that is the odontogenic cyst category (22%), and third is the immunological-mediated lesion category (13%). The sub-diagnosis that was mostly observed was radicular cyst, lichen planus, and focal fibrous hyperplasia with the percentages of 13.6%, 10.8%, and 9.4%, respectively. Conclusion: The findings provide important information about the oral and maxillofacial pathology in Al-Qassim region, Saudi Arabia. This study found that biopsied oral lesions were more prevalent in males and in patients in the fourth decade of life. The oral mucosa was the most biopsied site, and the majority of the biopsies were soft tissue pathological lesions and radicular cyst was the most frequent diagnosis. Knowledge of such demographic and clinical features of oral and maxillofacial pathology cases helps in prediction of disease incidence and subsequent proper patient care in the region.

Introduction: This study investigated the distribution pattern of tenascin-C and syndecan-1 in the dental mesenchyme during root development of immature swine teeth in order to define the differentiation dynamics of both pulp tissue progenitors and apical papilla cells, as well as to assess the adequacy criticize of the apical papilla to induce dentin-pulp regeneration. Methods: Three 7-month-old miniature swine were used in this study. A total of 12 teeth, including two immature permanent incisors and two premolar teeth of each case, were extracted and processed for histological and immunohistochemical analysis. Different populations of mesenchymal cells located at the root apex were morphologically evaluated in hematoxylin-eosin serial sections. Additionally, the distribution patterns of tenascin-C and syndecan-1 were assessed immunohistochemically. Results: Syndecan-1 was strongly expressed in the dental pulp, particularly along the odontoblasts of the root and the newly deposited predentin layer. Tenascin-C was intensely expressed in the dental pulp. The apical papilla and dental follicle showed no expression of either molecule. Conclusions: Cell differentiation potential in the developing swine apex is progressively restricted to the newly formed dental pulp, whereas phenotypic expression of apical papilla cells remains undetermined unless the new microenvironment triggers cell differentiation towards the odontoblastic lineage.

Background: Pain-related temporomandibular joint disorders (TMJD) are a major public health problem, including the diagnoses of disc displacement (DD) with and without reduction (DDwR/DDwoR). Objectives: The study aimed to examine the matrix remodeling and the inflammatory profile in synovial tissues of patients with TMJ-DD, with a view to understand the pathophysiology, and to contribute to the development of tissue-based diagnostic criteria. Methods: This laboratory-based observational case-control study included 30 synovial tissue samples obtained from 30 patients, diagnosed with delayed (DO) or sudden (SO) onset of DDwoR, which were compared against the reference patient material, DDwR (n = 10/diagnosis group). Tissue samples were investigated histologically and via quantitative immunohistochemistry for a panel of antibodies targeted against extracellular matrix proteins and inflammatory markers. The data were analyzed using a generalized linear model with a gamma family distribution (p < 0.05). Results: Quantification of immunostaining revealed significant differences in the distribution of collagen type III (DO, p < 0.001), lumican (DO, p < 0.05), matrix metalloproteinase-2 (DO, p < 0.05), CD4 T-helper cells (DO, p < 0.01; SO, p < 0.001), and CD68 monocytic immune cells (both SO and DO, p < 0.001) in DDwoR groups compared to the reference patient material, DDwR. Conclusions: The observations confirmed differences in matrix remodeling and an increase in local inflammatory activity in the DDwoR diagnosis compared to the reference patient material, DDwR. The study highlighted the importance of synovial tissue characterization to unite micropathology and clinical findings, leading to more reliable diagnostic tools.

Purpose: The aim of this study was to develop a competency framework based on entrustable professional activities (EPAs) in oral cancer management by postgraduate trainees in oral and maxillofacial surgery through expert consensus.

Materials and methods: The study design was based on a modified Delphi technique and involved iterative online surveys with two rounds of data collection and analysis. Initial development of the questionnaire identified five EPAs based on 42 competencies along with supervision level and assessment strategies. The first Delphi round involved administration of the survey questionnaire online to maxillofacial surgeons meeting the inclusion criteria for experts. Consensus was achieved on five EPAs and 36 competencies (≥80% response rate). Six competencies were rephrased and sent again in the Round 2 questionnaire to achieve a consensus.

Results: A total of 45 experts participated in Round 1 followed by input from 27 experts in Round 2 of the Delphi panel. Following two iterative rounds of online surveys and feedback, expert consensus was achieved to develop an EPA framework in five EPA domains focused on the management of oral cancer by postgraduate trainees in maxillofacial surgery including 38 specific competencies, supervision level, and assessment strategies. High content validity of the study was established through a comprehensive literature search, and expert feedback was evidenced by an excellent response rate (93.34%, and 64.28%) and a stringent criteria of response agreement amongst experts (≥80%).

Conclusion: In conclusion, this study employed expert consensus to identify five EPAs with 38 competencies along with the required supervision level of postgraduate maxillofacial trainees for the management of oral cancer. This EPA framework provides a roadmap for training supervisors to map the learning outcomes in oral oncology for postgraduate trainees in oral and maxillofacial surgery.

Background: Phenotype alterations of nociceptive neurons have been shown to be a key step in the pathogenesis of many pain-related diseases. However, it is unclear if the characteristic changes of temporomandibular joint (TMJ) primary afferent neurons are related to the pathogenesis of temporomandibular joint osteoarthritis (TMJOA) chronic pain. This study aimed to determine the morphological and neurochemical changes in trigeminal ganglion (TG) neurons innervating the TMJ in TMJOA chronic pain rats. Materials and Methods: Monosodium iodoacetate (MIA)-induced TMJOA chronic pain rat model was established (n = 6), and saline was injected in rats of the control group (n = 6). TMJ primary afferent neurons were labeled with retrograde tracing (Dil). The spatial distribution and the expression of calcitonin gene-related peptide (CGRP), isolectin B4 (IB4), and neurofilament 200 (NF200) of TMJ primary afferent neurons in TG were investigated using immunofluorescence. Intracellular calcium signaling was recorded by calcium imaging (n = 20). Results: TMJ primary afferent neurons were located only in the V3 region of the TG from both saline- and MIA-injected rats. The number of TG neurons innervating the TMJ was increased in MIA-injected rats. Elevated number and intracellular calcium concentration of small- and medium-sized instead of large-sized Dil+ TG neurons were found in MIA-injected rats. The upregulated expression of CGRP and IB4, but not NF200, in TG neurons innervating the rat TMJs was accompanied by TMJOA chronic pain. Conclusion: This study suggests that sensitization of small- to medium-sized Dil+ TG neurons and CGRP- and IB4-positive Dil+ TG neurons might contribute to the development of TMJOA chronic pain in rats. This will provide valuable information for more efficient control of TMJOA chronic pain.

Aim: The current review aims to explore postoperative neurological complications in third molar extractive surgery.

Materials and methods: The PRISMA protocols were followed when conducting this review. We found a total of 2,250 articles that matched our topic using the Boolean keywords, mandibular nerve complications AND oral surgery, from PubMed (1,083), Scopus (435), and Web of Science (732), with the filters of English language articles, time range January 1, 2003, to September 30, 2023, and human studies. After 762 duplicates were eliminated, there remained 1,488 articles. Eleven final articles were deemed of the highest relevance to our topic by eliminating articles in animals, non-English language, reviews, meta-analysis, and off-topic. A potential risk in the third molar extraction was temporary loss of sensibility often caused by mild compression or irritation of the mandibular nerve. This typically resolves within weeks or months, but in severe cases, recovery might take longer. Permanent loss of sensation can occur, indicating significant nerve damage and lasting effects on touch, temperature, or pain perception.

Conclusions: Various treatments exist for nerve damage, including low-level laser therapy, pain management medications, or physical therapy. While these therapies may improve neurosensory impairment, patients often report a decline in their quality of life.

Purpose: Children's fear of the injection of local anesthetic agents affects their cooperation in pediatric dentistry. Different techniques are available to decrease the injection pain, including the use of precooling agents or vibrators. The present study investigated the effectiveness of Buzzy (Buzzy MMJ Labs, Atlanta, GA, USA). This device transfers cold and external vibration to the injection site during the inferior alveolar nerve block (IANB) injection. Materials and Methods: The present self-control, randomized, and double-blind clinical trial evaluated 30 children aged 6-12, who had bilateral mandibular permanent or primary carious molar teeth. On one side, the BUZZY was applied before and during the IANB injection, and the other side was considered as control. On both sides, a topical anesthetic gel was applied before injection. The pain severity and children's anxiety were determined using Wong-Baker, face, leg, activity, cry, consolability (FLACC) scales, and the heart rate. Results: The mean age of the participants was 7.18 ± 1.5 years, with 12 girls and 18 boys. The Wong-Baker scale and FLACC scale did not show any statistically significant difference between BUZZY and control (p value = 0.9 and 0.15, respectively). In addition, BUZZY tool did not significantly decrease pain and anxiety during injection, assessed through the heart rate difference (p=0.38). Conclusion: Under the limitations of the present study, a combination of precooling and vibration using the BUZZY device did not decrease pain and anxiety in children during the IANB injection.