Association between pulp and periapical disease with type 2 diabetes: A bidirectional Mendelian randomization

AIM

This current Mendelian randomization (MR) study aims to comprehensively explore the potential bidirectional link between pulp and periapical disease (PAP) with type 2 diabetes mellitus (T2DM).

METHODOLOGY

Summary level data of European-based population genome-wide association studies (GWASs) were employed to undertake this MR study. With the selection of single nucleotide polymorphisms (SNPs) as the instrumental variable, the radial inverse-variance weighted (radial IVW) method with modified second-order weights was applied as the primary method. Additionally, a range of sensitivity analyses were conducted to investigate pleiotropy. Results from different sources of outcome were pooled by meta-analysis with the fixed model.

RESULTS

The results of this MR analysis did not suggest a significant impact of pulp and periapical disease on type 2 diabetes (combined OR = 1.04, 95% CI: 1.00-1.07, p = .033) and vice versa (OR = 1.04, 95% CI: 0.96-1.14, p = .329). No significant pleiotropy was detected in the final model after the removal of outliers, demonstrating the reliability of the results in our primary analysis.

CONCLUSIONS

With the limitations inherent in the present MR study, there is no significant evidence in either direction to suggest a causal association between pulp and periapical disease and type 2 diabetes mellitus.

The Role of Sensory Nerves in Dental Pulp Homeostasis: Histological Changes and Cellular Consequences after Sensory Denervation

Homeostatic maintenance is essential for pulp function. Disrupting pulp homeostasis may lead to pulp degeneration, such as fibrosis and calcifications. Sensory nerves constitute a crucial component of the dental pulp. However, the precise involvement of sensory nerves in pulp homeostasis remains uncertain. In this study, we observed the short-term and long-term histological changes in the dental pulp after inferior alveolar nerve transection. Additionally, we cultured primary dental pulp cells (DPCs) from the innervated and denervated groups and compared indicators of cellular senescence and cellular function. The results revealed that pulp fibrosis occurred at 2 w after the operation. Furthermore, the pulp area, as well as the height and width of the pulp cavity, showed accelerated reductions after sensory denervation. Notably, the pulp area at 16 w after the operation was comparable to that of 56 w old rats. Sensory denervation induced excessive extracellular matrix (ECM) deposition and increased predisposition to mineralization. Furthermore, sensory denervation promoted the senescence of DPCs. Denervated DPCs exhibited decelerated cell proliferation, arrest in the G2/M phase of the cell cycle, imbalance in the synthesis and degradation of ECM, and enhanced mineralization. These findings indicate that sensory nerves play an essential role in pulp homeostasis maintenance and dental pulp cell fate decisions, which may provide novel insights into the prevention of pulp degeneration.

Clinical and radiographic features of external cervical resorption - An observational study

AIM

To determine the prevalence of symptoms, clinical signs and radiographic presentation of external cervical resorption (ECR).

METHODOLOGY

This study involved 215 ECR lesions in 194 patients referred to the Endodontic postgraduate Unit at King's College London or Specialist Endodontic practice (London, UK). The clinical and radiographic findings (periapical [PA] and cone beam computed tomography [CBCT]) were readily accessible for evaluation. A checklist was used for data collection. Inferential analysis was carried out to determine if there was any potential association between type and location of tooth in the jaw as well as sex, age of the patient and ECR presentation and radiographic feature.

RESULTS

Eighty-eight patients (94 teeth) were female and 106 patients were male (121 teeth), the mean age (±SD) was 41.5 (±17.7) years. Fifteen patients (7.7%) had more than one ECR lesion. The most affected teeth were maxillary central incisors (21.4% [46 teeth]) and mandibular first molars (10.2% [22 teeth]). ECR was most commonly detected as an incidental radiographic finding in 58.1% [125 teeth] of the cases. ECR presented with symptoms of pulpal/periapical disease in 23.3% [n = 50] and clinical signs (e.g. pink spot, cavitation) in 16.7% [36 teeth] of the cases. Clinical signs such as cavitation (14%), pink spot (5.1%) and discolouration (2.8%) were uncommon, but their incidence increased up to 24.7% when combined with other clinical findings. ECR was detected in the resorptive and reparative phases in 70.2% and 29.8% of the cases respectively.

CONCLUSION

ECR appears to be quiescent in nature, the majority being asymptomatic and diagnosed incidentally from PA or CBCT. When assessed with the Patel classification, most lesions were minimal to moderate in relation to their height (1 or 2) and circumferential spread (A or B). However, the majority of ECRs were in (close) proximity to the pulp. Symptoms and clinical signs were associated with (probable) pulp involvement rather than the height and circumferential spread of the lesion. Clinical signs were more frequently associated when ECR affected multiple surfaces.

Effectiveness of diagnosing pulpitis: A systematic review

BACKGROUND

The diagnosis of the status of the inflamed pulp is essential in clinical diagnosis and treatment provision. There are a limited number of well-designed and well-executed clinical trials on the diagnosis of the true status of the pulp.

OBJECTIVES

Three PICO questions were formulated and agreed a priori by the European Society of Endodontology to evaluate the clinical tests for sensibility testing, determination of biomarkers and pulp bleeding with regard to their suitability to correctly diagnose the condition of the pulp tissue for the development of S3-Level guidelines.

METHODS

A literature search was conducted using PubMed, Clarivate Analytics' Web of Science, Scopus, Google Scholar and Cochrane Central Register of Controlled Trials from inception to 21 January 2022. Additionally, a hand search was performed, and the contents of the major subject journals were also examined. Eligibility criteria followed the proposed PICO questions. Two independent reviewers were involved in study selection, data extraction and appraising the included studies; disagreements were resolved by a third reviewer. The risk of bias was assessed by the QUADAS-2 tool for diagnostic accuracy studies, the Newcastle-Ottawa scale for noncomparative, nonrandomized studies and the Newcastle-Ottawa Quality Assessment scale adapted for cross-sectional studies.

RESULTS

In total, 28 studies out of 29 publications were considered eligible and were included in the review. Twelve studies were identified to investigate the diagnostic accuracy of the pulp vitality. Ten studies fulfilled the criteria to evaluate the diagnostic accuracy of the pulpal conditions, while 6 studies investigating the expression of biomarkers were eligible. Three studies addressing the prognostic factors and therapeutic interventions relating to pulpal status were included.

DISCUSSION

The core problem in pulp diagnostics is that a reliable reference standard is lacking under clinical conditions. Based on limited evidence, the most promising current approach seems to define a combination of different clinical tests and symptoms, probably in future including molecular diagnosis ("diagnostic package") will be required to ascertain the best possible strategy to clinically diagnose true pulpal conditions.

CONCLUSIONS

The effectiveness of diagnosing pulpitis is low due to limited scientific evidence regarding the accuracy and reproducibility of diagnostic tests. There is a lack of evidence to determine the true status of the pulp or to identify prognostic indicators allowing for a reliable pre-operative estimation of the outcome of vital pulp treatment.

REGISTRATION

PROSPERO database (CRD42021265366).

Prevalence of pulp canal obliteration and periapical pathology in human anterior teeth: A three-dimensional analysis based on CBCT scans

This study aimed to determine the prevalence of pulp canal obliteration (PCO) and its association with periapical pathology (Hypodense areas) in cone-beam computed tomography (CBCT) scans of anterior teeth. A total of 2161 CBCT scans from patients 18 years or older taken between 2000 and 2020 were selected. Patient-, tooth- and scan-related data were registered. Two calibrated evaluators recorded the number of teeth with PCO ≥4 mm in the cervical third of the roots and the presence or absence of periapical hypodensities (PH). The length of the root canal that was calcified was also determined. Logistic regression analysis was used to determine whether any of the recorded factors influenced the presence of PCO and the presence of periapical pathology in teeth presenting with PCO. The only factor significantly related to the presence of PCO was patient age. The prevalence of PH in teeth exhibiting PCO was 10%.

The Pulpal Response to Crown Preparation and Cementation

INTRODUCTION

This study aimed to evaluate the risk factors and occurrence of pulpal disease in patients who received either 'full coverage' (crowns) or 'large non-crown' restorations (fillings, inlays, or onlays, involving ≥3 surfaces).

METHODS

A retrospective chart review identified 2,177 cases of large restorations placed on vital teeth. Based on the restoration type, patients were stratified into various groups for statistical analysis. After restoration placement, those who required endodontic intervention or extraction, were classified as having 'pulpal disease'.

RESULTS

Over the course of the study, 8.77% (n=191) of patients developed pulpal disease. Pulpal disease was slightly more common in the 'large non-crown' group than the 'full coverage' group (9.05% vs. 7.54%, respectively). For patients that received large fillings, there was not a statistically significant difference based on operative material (Amalgam vs. Composite: OR = 1.32 [95% CI (0.94, 1.85)], P>0.05) or number of surfaces involved (3 vs. 4: OR = 0.78 [95% CI (0.54, 1.12)], P>0.05). The association between restoration type and pulpal disease treatment performed was statistically significant (P<0.001). The 'full coverage' group more frequently underwent endodontic treatment than extraction (5.78% vs. 3.37%, respectively). Only 1.76% (n=7) of teeth in the 'full coverage' group were extracted, compared to 5.68% (n=101) in the 'large non-crown' group.

CONCLUSIONS

It appears that ∼9% of patients who receive large restorations will go on to develop pulpal disease. The risk of pulpal disease tended to be highest in older patients who receive large (4 surface) amalgam restorations. However, teeth with 'full coverage' restorations were less likely to be extracted.

[Bioactive materials in endodontics]

Bioactive materials is defined as substances that elicit special chemical bonding at the interface between tissues and the material. In recent years, more and more bioactive materials have emerged in endodontic treatment. The present article introduces the definition, classification and application of bioactive materials in endodontics. Combined with evidence-based medicine and bioactive materials, optimum treatment recommendations for various endodontic diseases are provided and the development trend of bioactive materials in endodontics is also discussed.

[Discussion on combined periodontic-endodontic lesion type]

Combined the elaboration on periodontic-endodontic lesion in the textbook Periodontics with the deficiencies existed in the clinical and teaching work and demonstrated the understanding on the type of the combined periodontic-endodontic lesion, and suggested the viewpoint of no sub-type of combined periodontic-endodontic lesion. Only regard the type of pulp disease that induced by periodontal disease as genuine combined periodontic-endodontic lesion.

Crowns and extra-coronal restorations: considerations when planning treatment

Considerations when planning treatment is the third in the series of crowns and other extra-coronal restorations. Articles or chapters on treatment planning in restorative dentistry can make pretty dry reading, often built around a list of factors that might influence your decision-making. In truth though, planning and placing crowns or other extra-coronal restorations cannot be distilled into a series of lists. The decision-making involved requires experience, subtle understanding and a flexible approach, none of which come easily.

Recent development in endodontic research

In essence, endodontics as a clinical discipline is concerned with the prevention and treatment of pulpal and periapical infection. In recent research the infective process has been investigated as well as the mechanisms by which the pulp and periodontium deal with microbial insults. With regard to the pulp, findings on the hemodynamics of pulpitis suggest that the inflammatory response in this tissue is much less influenced by the special anatomic environment of the tooth than was previously believed. Pulpal diseases are being underdiagnosed, mostly because of inadequate examination methods. Laser Doppler flowmetry which gives a vascular rather than a nervous response may gain importance in pulpal diagnostics in the future. It is established that apical periodontitis with bone resorption cannot develop in the absence of bacteria in the root canal system. Root canal infection is characterized by a wide variety of combinations of relatively few anaerobic bacteria, and bacterial synergism plays an important role in maintaining the infection. Microbial invasion of an apical granuloma may take place. Non-oral and environmental organisms like Pseudomonas aeruginosa are frequently isolated from treatment-resistant cases. Success of endodontic treatment depends on the reduction or elimination of the infecting bacteria. This may predictably be obtained after a thorough chemo-mechanical instrumentation and disinfection of the root canal with calcium hydroxide. The standardized technique which entails the preparation of a cylindrical apical box with removal of significant amounts of dentin near the root apex predictably gives a clean canal. This technique has provided excellent clinical and radiographic results in well documented follow-up studies.

Four-phase study of computer-assisted and slide-tape methods of stimulating clinical endodontic problems

1. Computer-assisted instruction of stimulated clinical endodontic problems is superior to a slide-tape presentation for test selection but not for diagnosis and treatment planning. 2. The lack of a difference in diagnosis is likely due to the already superior performance of students in diagnosis at the University of Kentucky without computer assistance. A study with students of less background might reveal a difference in presentation methods. 3. Students with high GPSs score higher on a written test of endodontic clinical judgment. 4. Reliable results on the effects of a human tutor's supplementing machine instruction were not obtained. 5. Students felt that the problems presented in this study were useful in preparing for clinical treatment of patients. 6. After some exposure to machine methods of instruction, students divided into three sizable groups, one preferring a human teacher, another preferring a machine, and the third having no preference. The decision to use only machine or human instruction cannot then be made from student attitudes. 7. Students liked the active participation and immediate responses of the computer but not the time necessary to complete the problems. 8. Students liked the self-pacing, speed, and convenience of the slide-tape method but not the incompleteness of the problems presented by this method. 9. It appears that there is some justification from this study for offering both slide-tape and computer-assisted presentations to students.