Search Results (13)

The term “periapical lesion” refers to a pathological change in the tissues surrounding the apex of a tooth root, defined by its anatomical location rather than a distinct disease entity. Periapical lesions may be of endodontic origin, most commonly resulting from microbial infection of the root canal system following pulp necrosis due to caries, trauma, or other insults, or of non-endodontic origin, such as developmental cysts, benign and malignant odontogenic and non-odontogenic tumors, and fibro-osseous lesions. Accurate diagnosis requires a systematic approach combining patient history, clinical examination, pulp vitality testing, and radiographic assessment; histopathological evaluation is indicated when clinical and radiographic findings are inconsistent or suspicious. The pathophysiology of these lesions involves dynamic interactions between root canal microorganisms and the host immune-inflammatory response. The primary management for endodontic periapical lesions is root canal treatment, which aims to reduce or eliminate root canal microorganisms through mechanical debridement and chemical disinfection. Persistent or extensive endodontic lesions and non-endodontic lesions may require surgical intervention. Molecular and inflammatory biomarkers have been investigated as adjunctive tools for assessing disease activity and prognosis; however, these remain largely investigational and are not yet part of routine clinical practice. Future developments in artificial intelligence, advanced imaging, molecular diagnostics, and personalized therapies may enhance the diagnosis and management of periapical lesions, although further clinical validation is required. Full article

Background: Apical periodontitis (AP) is a common inflammatory condition of the periapical tissues, most often associated with persistent endodontic infection. Conventional two-dimensional radiography may underestimate AP because of anatomical superimposition and limited sensitivity. Cone-beam computed tomography (CBCT) allows three-dimensional visualization of periapical structures and has been increasingly used in epidemiological research. Objective: This study aimed to evaluate the prevalence and distribution of apical periodontitis, with particular emphasis on apical periodontitis associated with root canal-treated teeth (AP-RCT), in a Saudi subpopulation using CBCT imaging. Methods: This retrospective cross-sectional study analyzed CBCT scans of Saudi patients obtained for routine diagnostic purposes between 2017 and 2021. Apical periodontitis was identified using standardized radiographic criteria requiring the presence of periapical radiolucency in more than one imaging plane. Demographic and clinical variables were recorded. Descriptive statistics were used to estimate prevalence. Associations between demographic factors and AP-RCT counts were evaluated using multivariable negative binomial regression. Regional tooth distribution was analyzed using generalized estimating equation models accounting for within-participant clustering. Results: A total of 320 CBCT scans were analyzed. Apical periodontitis was detected in 231 participants (72.2%) and in 667 teeth (8.3% of examined teeth). Of the affected teeth, 457 (68.5%) were associated with root canal treatment. The mean number of AP-RCT per participant was 1.36 ± 1.81 (median: 1; IQR: 0–2). Multivariable analysis identified age as the only significant predictor of AP-RCT. Compared with individuals aged 21–30 years, higher AP-RCT rates were observed in the 31–40-year and 41–50-year age groups, while participants ≤20 years showed lower rates. Tooth-level analysis demonstrated higher AP-RCT prevalence in maxillary premolars, maxillary molars, and mandibular molars, whereas mandibular anterior teeth showed the lowest prevalence. Conclusions: Apical periodontitis, particularly AP-RCT, was frequently observed in this Saudi subpopulation when assessed using CBCT. Age and tooth location were the primary determinants of disease distribution. These findings provide population-level epidemiological data on the prevalence and anatomical distribution of apical periodontitis in root canal-treated teeth. Clinical Significance: CBCT-based epidemiological assessment enables detailed evaluation of the distribution of apical periodontitis in dentate populations and may assist in characterizing disease patterns in anatomically complex regions, without implying comparative diagnostic accuracy or treatment outcome assessment. Full article

Charcot–Marie–Tooth disease (CMT), caused by dominant loss-of-function mutations in DNM2, encoding the GTPase dynamin-2, impairs motor and sensory function. However, the respective contributions of muscle and nerve pathology, and the therapeutic potential of increasing DNM2 expression, remain unresolved. We evaluated tissue-targeted and systemic approaches to increase DNM2 in a mouse model carrying the common K562E-CMT mutation. Muscle-specific DNM2 overexpression from embryogenesis in Dnm2^K562E/+ mice ameliorated desmin and integrin mislocalization, membrane trafficking defects, mitochondrial abnormalities, and fibrosis in skeletal muscle, resulting in improved locomotor coordination despite persistent muscle atrophy. Conversely, systemic postnatal AAV delivery of human DNM2 increased DNM2 in muscle but failed to transduce nerves and paradoxically worsened the muscle pathology, producing centronuclear myopathy-like features. These findings reveal a primary pathogenic impact of DNM2-CMT mutation within skeletal muscle, independent of nerve involvement. Collectively, they underscore that precise DNM2 dosage is critical for neuromuscular homeostasis and reveal a narrow therapeutic window for safe and effective therapeutic intervention. This paradox, in which efforts to compensate for a loss-of-function neuropathy risk inducing a gain-of-function myopathy, highlights the need for tightly controlled modulation of DNM2 activity in future therapeutic strategies. Full article

Background/Objectives: Dentin hypersensitivity (DH) is associated with gingival recession and dentin exposure. Biomimetic hydroxyapatite (HAp) reduces DH by occluding dentinal tubules, with conventional toothpaste formulations showing benefits. High-density HAp mouthwashes may enhance bioavailability, but comparative evidence is scarce. This trial assessed the immediate desensitizing efficacy of a conventional HAp toothpaste and a high-density HAp mouthwash after professional oral hygiene. Methods: One hundred participants were randomized 1:1 to Biorepair^® (Coswell S.p.A., Funo, BO, Italy) Total Protection Toothpaste (Control) or Biorepair^® (Coswell S.p.A., Funo, BO, Italy) High-Density Mouthwash (Test). Assessments were performed at baseline (T0), post-debridement (T1), and after product use (T2). The primary endpoint was patient-level Schiff Air Index (SAI). Secondary endpoints included tooth-level SAI, Visual Analog Scale (VAS) scores, and gingival recession (GR). The trial was registered at ClinicalTrials.gov (NCT07057141) and followed CONSORT 2025 guidelines. Friedman and Dunn’s tests and regression models were applied. Results: Both groups showed significant reductions in hypersensitivity. Patient-level mean SAI decreased from 1.47 to 0.66 in the Control and from 1.48 to 0.45 in the Test group, while VAS declined from 3.66 to 1.57 (Control) and from 4.15 to 1.37 (Test). Post hoc analyses showed significant intragroup reductions between T0/T1 and T2 in both groups, with no significant differences between groups at any timepoint. GR remained stable across the study. Regression analyses identified follow-up time and GR as significant predictors, whereas treatment allocation was not, indicating that the acute advantage of the mouthwash at T2 did not persist once longitudinal trends were considered. Conclusions: Both HAp formulations effectively reduced dentin hypersensitivity 30 s after application. The high-density mouthwash exhibited slightly lower mean values at T2, although these differences were not statistically significant. Full article

Primary aggressive oral lymphomas (PAOL) are a rare subset of extranodal non-Hodgkin lymphomas arising in the oral cavity without evidence of other systemic involvement at diagnosis. PAOL accounts for only about 2–3% of all lymphomas. They most commonly belong to aggressive B-cell subtypes such as Diffuse large B-cell lymphoma (DLBCL) and plasmablastic lymphoma (PBL), with occasional cases of Burkitt lymphoma and T-cell/NK-cell lymphomas. Clinically, these malignancies often present with non-specific symptoms (e.g., swelling, pain, ulceration, tooth mobility) that mimic benign dental conditions, leading to diagnostic delays. An integrated diagnostic approach—combining thorough oral examination, imaging (CT, MRI, PET), and definitive biopsy with immunohistochemistry and genetic studies—is critical for accurate diagnosis and staging. Treatment typically involves systemic chemotherapy, often combined with rituximab for CD20+ tumors and adjunctive radiotherapy for localized disease. Ongoing research into the genomic and microenvironmental landscape of PAOL is paving the way for novel targeted therapies to improve outcomes. In HIV+ or transplant patients, PAOL are often driven by viral co-infections (EBV, HHV-8) and may require tailored therapy, including optimization of immune status. The dentist’s role encompasses not only diagnosis but also active participation in cancer therapy through preventive and supportive dental care, and persists thereafter by monitoring for recurrence and treating chronic treatment sequelae. This review provides a comprehensive overview of PAOL‘s epidemiology, clinical-pathologic and molecular features, current and emerging treatments, and the essential collaborative role of dentists and hematologists in patient care. Full article

Background/Objectives: The aim of this narrative review is to perform an updated literature review of the root canal microbiome in secondary endodontic infections and the bacterial dynamics that govern the processes leading to the development of these persistent endodontic infections and periapical lesions. Methods: A literature search of scientific publications issued in the last 8 years, i.e., 2017–2024, was conducted in PubMed (MEDLINE) and ScienceDirect databases, using the following keywords: endodontic microbiome; endodontic pathogens; periapical lesion; primary endodontic infection; secondary/persistent endodontic infection; functional redundancy. Discussions: Secondary endodontic infections (SEIs) are a highly prevalent pathological condition affecting a minimum of one tooth in more than half of adults worldwide. The transition from primary endodontic infection (PEI) to secondary endodontic infection (SEI) is mainly governed by Enterococus faecalis (EF) that invades and dominates the previous endodontic biofilm initiated by Fusobacterium nucleatum (FN). Conclusions: The findings from different studies indicate that secondary endodontic infections are polymicrobial. In SEIs, the microbial species interactions are crucial in influencing the ecology of infected root canals. The issue of the keynote pathogen is still under debate. Both EF and FN pathogens cooperate with neighboring residents. Functional redundancy of the endodontic microbiome explains how the ecological diversity modulates its pathogenicity. Full article

Background: Root canal treatment is an important element of dental treatment, and broken instruments are one cause of endodontic treatment failure. Broken instruments are rarely reported in primary teeth because of their inherently wider and relatively straighter root canals. We describe a case of a patient with a broken instrument in a primary tooth and reviewed the literature across three databases. Case presentation: A boy aged 7 years and 2 months was referred to our hospital because of pain persisting despite multiple dental treatments. Radiographic examination revealed a broken instrument in the maxillary right primary second molar. The patient experienced dental fear, so the treatment proceeded with the use of behavioral management and nitrous oxide, after which his pain disappeared. At the age of 9 years and 2 months, eruption of the successive permanent teeth was confirmed, and no pathological findings were observed except enamel hypoplasia. We undertook a literature review across three databases and found only two articles about broken instruments in primary teeth, neither of which described the eruption of the permanent teeth. All three cases involved primary molars. Conclusions: We removed a broken instrument from the root of a primary molar and performed root canal treatment, resulting in a good outcome for the primary molar until it was replaced with successive permanent teeth. Although rare, broken instruments in the roots of primary molars do occur, and care should be taken during root canal treatment of primary molars. Full article

The periodontal ligament (PDL) is a complex connective tissue that connects the tooth root to the dental alveolar bone and plays crucial mechanical roles. PDL also exhibits regenerative roles and regulatory functions to maintain periodontium integrity and homeostasis. While PDL exposure to oral microbial pathogens is common, virtually nothing is known regarding viral infections of PDL. In particular, human herpes simplex virus type 1 (HSV-1) persistently infects the oral cavity through infections of the oral epithelium, connective tissue and neurons. While the oral spread of HSV-1 is generally asymptomatic, this virus has also been implicated in various oral pathologies. In this study, using a primary cell model derived from PDL (PDL cells), and whole surgical fragments of PDL, we provide evidence supporting the efficient infection of PDL by HSV-1 and the promotion of cytopathic effects. Infection of PDL by HSV-1 was also associated with an acute innate inflammatory response, as illustrated by the production of antiviral interferons and pro-inflammatory cytokines. Furthermore, this inflammatory response to HSV-1 was exacerbated in the presence of bacterial-derived products, such as peptidoglycans. This work therefore highlights the ability of HSV-1 to infect mesenchymal cells from PDL, suggesting that PDL may serve as a viral reservoir for the periodontal spread of HSV-1. Moreover, this raises questions about HSV-1 oral pathogenesis, as HSV-1-associated cytopathic and inflammatory effects may contribute to profound alterations of PDL integrity and functioning. Full article

Background: We investigated the relationship between the mandibular Curve of Spee (COS) and a persisting primary second mandibular molar (ppM2) due to an agenesis of the second mandibular premolar, using a digital software technique. Methods: Digital dental casts were obtained from 200 patients at the Department of Orthodontics in Innsbruck and Vienna, Austria. Patients (age-, gender-, and malocclusion-matched) were equally divided into two groups (n = 100) according to the existence of a ppM2. COS depth, overjet, overbite, and angle-classification were measured digitally using the OnyxCeph3^TM (version 3.2.147) software. ANOVA and Kruskal–Wallis tests were used to analyze relationships. For statistical analyses, p < 0.05 was considered as statistically significant, p < 0.01 as highly significant. Results were visualized with box plots and bar charts. Results: The deepest COS was present in patients with a ppM2. Furthermore, a positive correlation was shown between COS depth and angle-class II, between COS depth and age, as well as between COS depth and overbite. No gender differences could be observed. Conclusions: In our study population the COS depth was dependent on whether there is a ppM2 due to an agenesis of a second mandibular premolar or not, as well as on the malocclusion in sagittal direction. Full article

Persistent primary tooth (PPT) is a prevalent clinical condition that occurs when a primary tooth is over-retained beyond the established period of its normal exfoliation time, remaining in the oral cavity. Many factors could be involved in the risk of PPT; therefore, the aim of this study was to evaluate if single nucleotide polymorphisms (SNPs) in the COX2 gene are associated with PPT. Children undergoing orthodontic treatment were screened. Orthopantomographs were assessed to evaluate PPT according to the Nolla stage of its permanent successor. The primary tooth was considered retained when its successor permanent tooth was in Nolla stage 8 and below the alveolar crypt, Nolla stage 9, or Nolla stage 10. A saliva sample from each child was collected and used for DNA extraction. A real-time PCR of two SNPs, rs689466 (−1195 G/A) and rs5275 (+665 T/C), was performed. A chi-square test was used to compare the allele and genotype distribution. Haplotype analysis was also performed. A total of 100 children were included in the study. Fifty-one had at least one PPT, while 49 children were classified as a control. The number of teeth persistent in the oral cavity ranged from 1 to 8. The genotype distribution was associated with PPT in the co-dominant model (p = 0.006) for SNP rs5275. The individuals that carry two T alleles (TT) compared with the individuals that carry at least one C allele (C + TC) had an almost three times higher chance of presenting with PPT (p = 0.012; OR = 2.99, CI95% 1.28 to 6.95–recessive model). The haplotype C-A for the SNPs rs5275 and rs689466, respectively, was significantly associated (p = 0.042). In conclusion, single nucleotide polymorphisms in the gene encoding for COX2 are associated with persistent primary tooth and may delay permanent tooth eruption. Full article

Background: The permanent maxillary canine is the most impacted tooth after third molars. There are many possible surgical techniques to approach impacted canines. The literature reports that high-intensity laser therapies (HILTs) can be used for opercolectomy of an impacted tooth. The aim of this study is to propose a new orthodontic-surgical approach using a laser for the disinclusion of palatally impacted canines. Methods: Nine patients presented maxillary primary canine persistence in the dental arch. Orthopanoramic X-ray and cone beam computed tomography (CBCT) showed the impaction of permanent maxillary canines. Surgical exposure was performed using a diode laser (Raffaello, DMT, Lissone, Italy, 980 nm + 645 nm). No orthodontic devices were applied for impacted tooth traction. Canine movement was monitored at 1, 8, 16 weeks post-surgery with photos and a CS3500 intraoral scanner (Carestream Dental, Atlanta USA) to evaluate their autonomous eruption. Results: No complications were observed. In all the cases, complete disimpaction of the treated canines was obtained in only four months. Conclusions: Impacted canine exposure with a diode laser has many advantages if compared with traditional surgery. The pre-orthodontic exposure and autonomous eruption of impacted canines provided simplified and predictable outcomes. The absence of traction and the reduced time for orthodontic treatment increased compliance during the orthodontic alignment. Full article

Caries is the most common cause of pulp-periapical disease. When the pulp tissue involved in caries becomes irreversibly inflamed and progresses to necrosis, the treatment option is root canal therapy because the infected or non-infected necrotic pulp tissue in the root canal system is not accessible to the host's innate and adaptive immune defense mechanisms and antimicrobial agents. Therefore, the infected or non-infected necrotic pulp tissue must be removed from the canal space by pulpectomy. As our knowledge in pulp biology advances, the concept of treatment of pulpal and periapical disease also changes. Endodontists have been looking for biologically based treatment procedures, which could promote regeneration or repair of the dentin-pulp complex destroyed by infection or trauma for several decades. After a long, extensive search in in vitro laboratory and in vivo preclinical animal experiments, the dental stem cells capable of regenerating the dentin-pulp complex were discovered. Consequently, the biological concept of ‘regenerative endodontics’ emerged and has highlighted the paradigm shift in the treatment of immature permanent teeth with necrotic pulps in clinical endodontics. Regenerative endodontics is defined as biologically based procedures designed to physiologically replace damaged tooth structures, including dentin and root structures, as well as the pulp-dentin complex. According to the American Association of Endodontists’ Clinical Considerations for a Regenerative Procedure, the primary goal of the regenerative procedure is the elimination of clinical symptoms and the resolution of apical periodontitis. Thickening of canal walls and continued root maturation is the secondary goal. Therefore, the primary goal of regenerative endodontics and traditional non-surgical root canal therapy is the same. The difference between non-surgical root canal therapy and regenerative endodontic therapy is that the disinfected root canals in the former therapy are filled with biocompatible foreign materials and the root canals in the latter therapy are filled with the host's own vital tissue. The purpose of this article is to review the potential of using regenerative endodontic therapy for human immature and mature permanent teeth with necrotic pulps and/or apical periodontitis, teeth with persistent apical periodontitis after root canal therapy, traumatized teeth with external inflammatory root resorption, and avulsed teeth in terms of elimination of clinical symptoms and resolution of apical periodontitis. Full article

To persist in the oral cavity, bacteria must be able to tolerate rapid and substantial environmental fluctuations, particularly in pH and nutrient source and availability. Various species of Streptococcus, one of the most abundant genera in the mouth, are associated with oral health, as well as with dental caries. Cariogenic streptococci depend on a biofilm lifestyle for survival and persistence in the oral cavity and have developed sophisticated mechanisms to cope with environmental stresses. Here, we analyze the primary factors that allow these bacteria to emerge as significant members of tooth biofilms during adverse conditions. Our focus is on the molecular mechanisms of biofilm formation, stress tolerance and sugar metabolism by pathogenic oral streptococci, mainly Streptococcus mutans. Overlaps in the roles and regulation of these virulence attributes are highlighted and areas of research that deserve further investigation are proposed. Full article