Quintessence International, 10/2019

Every orthograde endodontic procedure requires restoration of the coronal (access) cavity. The specific type of treatment used in individual cases greatly depends on the amount and configuration of the residual coronal tooth structure. In practice there are Class I access cavities as well as coronally severely damaged, even decapitated, teeth and all conceivable manifestations in between. The latest attempts to review results from clinical trials to answer the question of whether post placement or crowning can be recommended for the restoration of endodontically treated teeth or not are inconclusive. For dental practitioners, this is not a satisfactory result. This appraisal evaluates available evidence and trends for coronal restoration of single endodontically treated teeth with a focus on clinical investigations, where available. It provides specific recommendations for their coronal restoration to assist clinicians in their decision making and treatment planning. Keywords: coronal restoration, direct restoration, endodontically treated teeth (ETT), endodontics, fiber post, indirect restoration, seal

Objective: To analyze the antimicrobial activity of photodynamic therapy as an adjunct to conventional endodontic treatment, particularly against Enterococcus faecalis. Method and materials: A total of 42 single-rooted teeth obtained from 33 patients with apical periodontitis were included. Sampling was developed in three stages: (1) immediately after accessing the root canal, (2) after chemical and mechanical instrumentation, and finally, (3) after photodynamic therapy application. The bacterial load of each sample was quantified by seeding on blood agar plates and selective M-Enterococcus agar. All growing colonies were identified using MALDI-TOF (Bruker; matrix-assisted laser desorption/ionization time-of-flight), and the entire bacterial microbiota composition was determined in the first sample by PCR-DGGE (polymerase chain reaction denaturing gradient gel electrophoresis), using 16 rDNA primers and selective nucleotide sequencing. Results: The endodontic therapy obtained a mean reduction in the cultivable bacterial load of 1.12 log, whereas the photodynamic therapy combination significantly increased the bacterial clearance (P .0001). Viable cells of E faecalis were detected in 16.6% of root canals, with a mean value of 93 CFU per tooth, which was reduced to 67 and 9 CFU/tooth after conventional endodontic and photodynamic therapy treatments, respectively. Molecular E faecalis detection demonstrated that this species was present in 23.2% of baseline samples. DGGE analysis demonstrated the existence of a more complex microbiota than those observed using classical cultures. Conclusion: Photodynamic therapy as an adjunct to root canal treatment produces a significant reduction in E faecalis bacterial load, and it should be considered in the prevention of apical periodontitis. Keywords:  apical periodontitis, endodontics, Enterococcus, oral microbiota, photodynamic therapy

Objectives: The standard application of a mean value of 2.04 mm for the biologic width has been demonstrated to result in inconsistent amounts of tooth extension following a crown lengthening procedure. Biologic width has been replaced by the supracrestal gingival tissue dimension, which includes the biologic width and sulcular depth. The question whether supracrestal gingival tissue dimension established at tissue maturation following a crown lengthening procedure is not significantly different from the presurgical dimension has not been fully answered. The primary objectives of the present prospective clinical study were to compare the preoperative and the 24-week dimensions of supracrestal gingival tissue following a crown lengthening procedure and assess the alterations in gingival margin position. A secondary objective was to assess selected patient- and surgery-related factors on supracrestal gingival tissue reestablishment. Method and materials: Twenty adult systemically healthy patients requiring a crown lengthening procedure were recruited for the study. A crown lengthening procedure was performed at 33 teeth and the patients were followed up to 24 weeks. The following parameters were recorded using customized stents for measurement reproducibility: stent-gingival margin (baseline, immediately after surgery, and at 6, 12, and 24 weeks), stent-bottom of sulcus (baseline and at 6, 12, and 24 weeks), stent-bone crest (baseline, at completion of osseous resection, and at 24 weeks), bone thickness (baseline, postsurgery), buccal gingival thickness (baseline, 24 weeks), and radiographic interproximal bone width (baseline, 24 weeks). Supracrestal gingival tissue, crown extension, and distance between the immediate postoperative position of the gingival margin relative to the contoured bone crest (F) were calculated. Results: There were no statistically significant differences between supracrestal gingival tissue measurements at baseline and at 24 weeks for any of the four tooth sides. Crown extension remained significantly increased at 24 weeks compared to baseline for all sides, with the largest amounts of gingival creeping mesially and distally. A highly significant positive correlation (r = 0.97, P .001) was demonstrated between flap positioning and stability of the gingival margin during the healing period. The closer was the F measurement to baseline supracrestal gingival tissue dimension, the less change in gingival margin was observed. Conclusions: The preliminary results of this investigation suggest the following: The presurgical supracrestal gingival tissue dimension can be used as a guideline measurement in crown lengthening procedures as it is reestablished with a similar apico-coronal dimension 24 weeks postoperatively; and crown extension is stable when the distance between the sutured gingival margin and the contoured osseous crest is similar to the preoperative supracrestal gingival tissue dimension. Keywords: biologic width, crown lengthening, flap positioning, osseous resection, supracrestal gingival tissue

Over the past decades, the walking bleach technique using sodium perborate was considered a safe and effective method to bleach nonvital discolored teeth. However, sodium perborate has been classified as carcinogenic, mutagenic, and toxic for reproduction by European Union legislation. Its use is therefore prohibited since April 2015. The initially described inside/outside bleaching technique, combining internal and external application of 10% carbamide peroxide, is an alternative to the walking bleach technique using sodium perborate. While good esthetic results and low risks of external cervical resorptions have been associated with this technique, its main drawback is that the access cavity is left open. To overcome this disadvantage, the present authors propose to seal the bleaching agent in the access cavity instead of leaving the latter open. Through a clinical case, this paper presents and discusses several aspects of this protocol, including the clinical steps, the design of the bleaching tray, and the treatment of potential recurrences. The present authors believe that the protocol proposed in this article is easier to use for the patient. Moreover, it prevents the accumulation of food debris in the access cavity and avoids the colonization of coronary dentin by bacteria. Keywords: carbamide peroxide, case report, inside/outside bleaching technique, sodium perborate, walking bleach technique

Objectives: The bidirectional relationship between diabetes mellitus and chronic periodontitis is well known from clinical trials. Periodontitis in diabetic patients is characterized by severe inflammation and tissue destruction. The purpose of this study was to investigate the levels of chromogranin A (CgA), a stress marker, and myeloid-related protein (MRP)-8/14, an inflammatory marker, in saliva from patients with periodontitis and diabetes mellitus, and to investigate the relationship between CgA and MRP-8/14 in all individuals and in the three groups separately. Method and materials: Stimulated saliva was collected from 20 diabetic patients with chronic periodontitis, 16 patients with chronic periodontitis, and 21 healthy individuals. Salivary CgA and MRP-8/14 were determined with enzyme-linked immunosorbent assay. Salivary CgA and MRP-8/14 levels were assessed in the saliva of diabetic periodontitis and periodontitis patients, and the relationship with periodontal disease severity was investigated. Results: CgA values in saliva samples from chronic periodontitis patients and diabetic patients with chronic periodontitis were significantly higher than those of the control group. MRP-8/14 values in saliva from chronic periodontitis patients and diabetic patients with chronic periodontitis was significantly higher than that in the control group. Salivary CgA level was positively correlated to MRP-8/14 in all individuals, but there was no significant correlation within the chronic periodontitis patient group, diabetic patients with chronic periodontitis group, and the healthy patient group. No significant correlation between salivary CgA/MRP-8/14 and clinical parameters of periodontitis was found in the three groups. Conclusions: The results suggest that salivary CgA and MRP-8/14 could be related to the pathogenesis of periodontitis and diabetes. CgA concentration in saliva was positively associated with increased MRP-8/14 in all individuals. Keywords: chromogranin A, diabetes, MRP-8/14 (myeloid-related protein-8/14), periodontitis, saliva

Preauricular swelling followed by limited mouth opening can be a challenging diagnosis. All anatomical structures and related pathologies should be examined. A 41-year-old woman presented to the Emergency Room complaining of limited mouth opening, severe pain that was worse on chewing, and swelling over her right temporomandibular joint (TMJ) that had started 3 days previously. Physical examination revealed localized swelling and redness over her right TMJ. Her right masticatory muscles were very painful and tender on palpation. Mouth opening was slightly limited. A computed tomography (CT) scan demonstrated a collection adjacent to her right TMJ, and reactive arthritis was diagnosed. Aspiration and arthrocentesis were performed, leading to immediate improvement. When symptoms returned 6 months later, magnetic resonance imaging (MRI) demonstrated a cystic lesion adjacent to the TMJ. Under general anesthesia an excisional biopsy was performed, and the pathologic examination revealed fibrous connective tissue with pseudocyst-like formation compatible with ganglion cyst. This case report demonstrates that a CT scan might lead to an incorrect diagnosis, whereas MRI scanning led to the correct diagnosis, thereby emphasizing the importance of choosing the right imaging modality. When a pathologic process of the TMJ is suspected, MRI is the gold standard imaging modality to diagnose the exact TMJ pathology. Complete surgical excision of ganglion cyst is recommended to determine a definite diagnosis. The final diagnosis should eventually be made by combining standard histology and MRI findings. Keywords: ganglion cyst, reactive arthritis, temporomandibular disorders (TMD), temporomandibular joint (TMJ)

Objective: To determine the risk of developing meningiomas after exposure to various types of dental ionizing radiation at diagnostic levels. Method and materials: A literature review was conducted using databases such as PubMed, Scopus, Google Scholar, CINAHL, Clinical Key, and Web of Science. Data extracted from the studies were tabulated and a meta-analysis was performed using all relevant data. Results: Twelve articles related to the topic that met the selection criteria were initially included in the systematic review. After evaluating the methodology and statistical analysis of each study, six were ultimately included in the meta-analysis. A forest plot created using RevMan v5.3 software (Cochrane Collaboration) produced a weighted odds ratio of 1.13 (95% confidence interval, 1.06 to 1.19) for meningioma risk. Conclusions: Studies in the recent past have found a positive association between exposure to ionizing radiation and risk of developing meningiomas. In this study, no association was found between dental x-ray exposure and the development of meningioma. The data were weighted heavily for one of the subgroups due to a larger patient pool as noted via the forest plot. Regardless of the weighting, the majority of the subgroups showed no significant association, further strengthening this conclusion. Keywords: brain tumor, dental x-rays, ionizing radiation, meningioma, meta-analysis, risk assessment

Objective: Scientific papers and books on digital dentistry are in vogue. In most cases, these publications focus clearly on the - undoubted - potentials and possibilities offered by digitalization. The fact that digital dentistry necessarily entails risks and ethical challenges, by contrast, is rarely discussed. This paper aims to complement the discourse on digitalization in dentistry by analyzing precisely these challenges. Method and materials: The study is based on an analysis of international publications and specialist writings on digitalization and its applications in the fields of dentistry and medicine, as well as on the analysis of specific contributions from the disciplines of medical ethics and medical law, and from the public media. Results: The paper identifies and discusses eight core challenges: (1) big data ("digital double" and falsification in dentistry), (2) the dental practitioner-patient relationship, (3) digital literacy, (4) the assumption of responsibility in complex systems, (5) accompanying changes in the dental professions, (6) cost trap and risks of overtreatment in dentistry, (7) consumption spiral and ecologic footprint, and (8) clinical evidence in dental treatments. In addition, a catalog of criteria for assessing the effects of digitalization in dentistry is developed. Conclusion: It is crucial to closely monitor both the potentials and the challenges posed by digitalization in dentistry. Ultimately, it is only those problems that are identified as such that can be resolved and only those technologies that are accepted by dentists, patients, and society that will prevail in the long term. Keywords: big data, clinical evidence, diffusion of responsibility, digital literacy, overtreatment

An important mission statement for modern dentistry is to maintain patients' implants and teeth for a lifetime. As a corollary, a standardized dental caries risk classification should provide the basis for evidence-based specific therapies. This paper proposes that interproximal caries lesions, also termed "restorative invasion," which destroys natural anatomical tooth structure with periodontal and occlusal sequelae, is a key factor in the cascade of destruction of the dentition and periodontitis. Thus it can serve as the basis for caries risk assessment. The standardized Dental Risk Classification system proposed here can provide a basis for therapeutic modalities as well as for public health assessment and insurance reimbursement. Keywords: dental caries, oral health, periodontitis, preventive dentistry, risk assessment, side effects, xerostomia