Detection, treatment and prevention of endodontic biofilm infections: what's new in 2020?

Endodontic disease, a biofilm infection of the root canal space, is a significant cause of dental morbidity worldwide. Endodontic treatment, or root canal treatment, as it is commonly known is founded on the ability to eradicate microbial biofilm infection and prevent re-infection of the highly complex root canal space. Despite many "advances" in clinical endodontics we have seen little improvement in outcomes. The aim of this critical review paper is to provide a contemporary view of endodontic microbiology and biofilm polymicrobiality, provide an understanding of the host response, and how together these impact upon clinical treatment. Ultimately, it is intended to provide insight into novel opportunities and strategies for the future diagnostics, treatment, and prevention of endodontic disease.

Oral microbial biofilms: an update.

Human oral cavity (mouth) hosts a complex microbiome consisting of bacteria, archaea, protozoa, fungi and viruses. These bacteria are responsible for two common diseases of the human mouth including periodontal (gum) and dental caries (tooth decay). Dental caries is caused by plaques, which are a community of microorganisms in biofilm format. Genetic and peripheral factors lead to variations in the oral microbiome. It has known that, in commensalism and coexistence between microorganisms and the host, homeostasis in the oral microbiome is preserved. Nonetheless, under some conditions, a parasitic relationship dominates the existing situation and the rise of cariogenic microorganisms results in dental caries. Utilizing advanced molecular biology techniques, new cariogenic microorganisms species have been discovered. The oral microbiome of each person is quite distinct. Consequently, commonly taken measures for disease prevention cannot be exactly the same for other individuals. The chance for developing tooth decay in individuals is dependent on factors such as immune system and oral microbiome which itself is affected by the environmental and genetic determinants. Early detection of dental caries, assessment of risk factors and designing personalized measure let dentists control the disease and obtain desired results. It is necessary for a dentist to consider dental caries as a result of a biological process to be targeted than treating the consequences of decay cavities. In this research, we critically review the literature and discuss the role of microbial biofilms in dental caries.

Targeting Enterococcus faecalis biofilms with phage therapy.

Phage therapy has been proven to be more effective, in some cases, than conventional antibiotics, especially regarding multidrug-resistant biofilm infections. The objective here was to isolate an anti-Enterococcus faecalis bacteriophage and to evaluate its efficacy against planktonic and biofilm cultures. E. faecalis is an important pathogen found in many infections, including endocarditis and persistent infections associated with root canal treatment failure. The difficulty in E. faecalis treatment has been attributed to the lack of anti-infective strategies to eradicate its biofilm and to the frequent emergence of multidrug-resistant strains. To this end, an anti-E. faecalis and E. faecium phage, termed EFDG1, was isolated from sewage effluents. The phage was visualized by electron microscopy. EFDG1 coding sequences and phylogeny were determined by whole genome sequencing (GenBank accession number KP339049), revealing it belongs to the Spounavirinae subfamily of the Myoviridae phages, which includes promising candidates for therapy against Gram-positive pathogens. This analysis also showed that the EFDG1 genome does not contain apparent harmful genes. EFDG1 antibacterial efficacy was evaluated in vitro against planktonic and biofilm cultures, showing effective lytic activity against various E. faecalis and E. faecium isolates, regardless of their antibiotic resistance profile. In addition, EFDG1 efficiently prevented ex vivo E. faecalis root canal infection. These findings suggest that phage therapy using EFDG1 might be efficacious to prevent E. faecalis infection after root canal treatment.

Self-etching adhesives: possible new pulp capping agents to vital pulp therapy.

Pulp capping is one of the solving for keeping vital pulp in the case of dentin caries, reversible pulpitis or traumatic pulp exposure. The presence of bacteria on the cavity walls or in the pulp was the major factor that leads to the failure of pulp capping. Traditional pulp capping agent, calcium hydroxide, may not prevent microleakage. Selfetching system is a newly developed adhesive system, which could provide less microleakage and would not break down or dissolve, preventing the oral fluids and bacteria from the pulp along the cavity wall. This may reduce such clinical problems as postoperative sensitivity, secondary caries and marginal discoloration. Researches showed that some kinds of self-etching adhesives induced the mild to moderate inflammatory pulp response, with negative bacterial staining. Inclusion of antibacterial components into self-etching system, such as 12-methacryloyloxydodecylpyridinium bromide (MDPB) may inhibit bacteria and provide better clinical effects. It is speculated that using the self-etching adhesive system containing the antibacterial agent, such as MDPB, to the dental pulp directly or indirectly, may inhibit bacteria after the placement of restoration as well as residual bacteria in the cavity.

Facing the challenges of ceramic veneers.

Ceramic veneers are extremely popular and have been used for many years. In spite of their phenomenal success, they offer numerous challenges during service. In this column, I have identified and discussed several degenerative situations commonly observed, and I have described methods of preventing or reducing the problems. When properly placed, ceramic veneers are among the most beautiful and long-lasting of all dental restorations.

Nd:YAG laser em Dentística: revisão de literatura / Nd:YAG laser in dentistry: review of literature

O Nd: YAG laser trabalha no comprimento de onda infravermelho, dentro do espectro invisível, com alta densidade de potência. Tem sido empregado nos tecidos duros dentais com diversas finalidades. Em Dentística Restauradora pode ser usado para selar regiões de cicatrículas e fissuras, impedindo que haja colonização bacteriana, principalmente em fissuras estreitas e profundas. Pode ser usado para aumentar a resistência ácida do esmalte, aumentando inclusive a incorporação de íons fluoreto e fortalecendo o dente contra desmineralização. Na Endodontia, pode ser usado em apicectomias para descontaminação do leito cirúrgico e obliteração dos túbulos dentinários. Em Odontologia Adesiva, na oclusão parcial ou total dos túbulos dentináiros. Procura minimizar o ingresso de fluidos, bactérias e produtos tóxicos em direção ao tecido pulpar. O laser é uma nova alternativa na Dentística, introduzindo uma concepção modernizada nas filosofias preventivas e restauradoras

In search of endodontic pathogens.

Success of root canal therapy depends on the complete eradication of microflora from the root canal system. A great deal of research is needed to identify and define the role of the pathogens which are involved in the pathogenesis of the periradicular diseases. This will help the endodontist to plan the best treatment by irradiation of pathogens which, in turn predict the outcome of the treatment. This article reviews the endodontic microflora, routes of microbial entry, methods to identify endodontic microbes and markers that permit the clinician to know when to conclude the treatment.

Evaluation of aggressive pulp therapy in a population of vitamin D-resistant rickets patients: a follow-up of 4 cases.

This investigation collected clinical and radiographic data from a retrospective chart review of 4 patients receiving prophylactic formocresol pulpotomies and stainless steel crowns following a dental abscess associated with a medical diagnosis of vitamin-D resistant rickets (VDRR) at Texas Scottish Rite Hospital for Children in Dallas, Tex. Clinical and radiographic data were available for 29 primary teeth in 4 children, with follow-up times ranging from 2 years, 1 month to 5 years, 6 months. Based on available recalls of 29 teeth treated following the prophylactic formocresol pulpotomy, 22 failed clinically. The earliest failure occurred at 3 months; the longest time to failure was 3 years, 9 months. No trends were discernable between tooth type and failure rate, although the shorter the time between eruption of the tooth and pulpotomy treatment, the greater the chance of success. Presently, there is not enough evidence to suggest that prophylactic pulpotomy therapy in VDRR patients is beneficial in preserving their primary dentition.

Preserving the vital pulp in operative dentistry: 3. Thickness of remaining cavity dentine as a key mediator of pulpal injury and repair responses.

Confusion surrounds the pivotal role played by the remaining dentine thickness in a cavity in determining pulpal injury and repair response outcomes after restorative treatment. The multifactorial nature of the injury repair response requires that attention is focused on the most important factors, including remaining dentine thickness, to harness the natural regenerative properties of the pulp and to avoid postoperative treatment complications.

An in vivo evaluation of hemorrhage control using sodium hypochlorite and direct capping with a one- or two-component adhesive system in exposed nonhuman primate pulps.

OBJECTIVE: This study evaluated the biologic ability of sodium hypochlorite to control hemorrhage via chemical amputation of the coagulum, to remove dentin chips, to assist healing, and to facilitate formation of a dentinal bridge under two adhesive systems. METHOD AND MATERIALS: Ninety Class V cavities with mechanical pulpal exposures were placed in the teeth of five adult monkeys and histologically observed. All exposures were prepared with a No. 330 bur, and hemorrhage was controlled with 3% sodium hypochlorite. Twenty-two exposures were capped with All-Bond 2 and AElitefil, and 26 exposures were capped with One-Step (OS) and Resinomer (RS). Two pulps were excluded from the final data. Forty-two exposures were capped with calcium hydroxide and amalgam as controls. At 7, 27, and 90 days, tissues were obtained by perfusion fixation, demineralized, sectioned, stained, and histologically graded according to published qualitative criteria. RESULTS: For both adhesives, at 7 days, 12 of 16 pulps showed no coagulum remnants or dentin chips at the material interface. No necrotic pulps were observed. At 27 and 97 days, 26 of 30 capped pulps had dentinal bridges at the adhesive interface. Reparative dentin was present in 28 pulps. Four 97-day pulps exhibited necrosis associated with stained bacteria. One 97-day pulp contained dentin chips throughout the pulp and demonstrated no healing, no reparative dentin, and no stained bacterial profiles. CONCLUSION: Normal soft tissue reorganization and dentinal bridge formation were observed in 86% of pulps treated with sodium hypochlorite and either adhesive system.

Dens evaginatus--how does it present and how should it be managed?

Dens evaginatus is a developmental dental anomaly predominantly affecting premolars in people of Mongolian origin. It is likely to become more prevalent in New Zealand due to the increase in immigration of Asians. The formation of dens evaginatus is postulated to be an abnormal evagination of the internal enamel epithelium and dental papilla into the stellate reticulum during morphodifferentiation. An important complication resulting from damage to the evagination is periapical abscess. When considering treatment options, the long-term prognosis of the tooth, its root length, the general alignment of the teeth, and overall arch length should be reviewed. Management options include composite resin placed at the base of the tubercle, excision of the tubercle followed by direct or indirect calcium-hydroxide pulp capping and composite-resin restoration, and apexification procedures followed by conventional endodontic therapy. Grinding of the intact tubercles of newly erupted evaginated premolars may contribute to secondary infection of the pulp, and is not recommended.

Avaliação clínica da saúde pulpar de primeiros molares permanentes jovens / Clinical evaluation of pulp dissease in early first permanent molars

Este estudo se propôs a verificar as condições pulpares dos primeiros molares permanentes de escolares da cidade de Niterói(RJ) atendidos no Projeto de Saúde Bucal da Faculdade de Odontologia da Universidade Federal Fluminense (FO-UFF). Participaram do estudo 406 escolares de ambos os sexos, entre 6 e 14 anos, que foram submetidos ao exame clínico, anamnese e testes desensibilidade para verificação das condições pulparesdos primeiros molares permanentes. Do total da amostra (1611 dentes), 1020 (63,32 por cento)) dentes estavam hígidos, 145 (9 por cento) restaurados, 412 (25,57 por cento) cariados sem envolvimento pulpar ou com inflamação pulpar reversível, 15 (0,93 por cento) com necrose pulpar e 8 (0,5 por cento) já haviam sido extraídos na época do exame. Somente 43,6 por cento das crianças apresentavam todos os primeiros molares permanentes hígidos, demonstrando a alta prevalência de cárie e uma considerável percentagem de alterações pulpares, ao levarmos em consideração a faixa etária estudada

Advances in endodontics.

Progress in diagnosis, prevention of diseases, treatment of exposed pulp, root canal treatment, retreatment and surgery is reported. Contemporary biological research techniques could set the foundation for a more rational approach to treatment. Pulp inflammation may be prevented by inhibiting bacteria from colonising dentine surfaces. Specific factors could be synthesised to stimulate normal dentine deposition over pulp exposures. Significant improvements have been made in instruments and techniques available for root canal treatment and surgery but there is no clinical evidence that they improve periapical healing.

Caries and dentin. Myths & consequences.

The dentin-pulp complex is sensitive to infection. Restorative treatment should function as a Band-Aid protecting the dentin-pulp complex from bacteria and their byproducts. This article describes different ways of treating the exposed dentin-pulp complex in such a way that bacterial infection can be avoided.

Dens invaginatus--a pathway to pulpal pathology: a literature review.

Dens invaginatus is the most common dental anomaly in a group of dental anomalies, related by their embryologic development and by the fact that their defects provide a potential pathway for bacteria to cause pulpal pathology. It occurs when the inner enamel epithelium invaginates into the dental papilla prior to calcification. It exists in erupted teeth as an enamel-lined tract, which either ends in a blind sac inside the crown or root or exits into the periodontal ligament. The lining may be incomplete in areas and may not protect the pulp. Methods of providing preventive treatment for teeth with dens invaginatus are described. When pulpal pathosis occurs, the dens may displace the pulp and complicate access cavity preparation and subsequent endodontic treatment, adversely affecting the prognosis. The learning objective of this article is to present treatment planning considerations and suggestions.