Keivan Zoufan DDS, MDS

2. The controversy concerning the depth of caries excavation: the myths and the facts In the previous introductory post I have presented a number of clinical si...tuations, that in my intention should serve as points of discussion, clarification, inquiry and debate. In fact every clinician, endodontist or generalist, has often treated the pulpal complications of caries left under restorations. In the present posts, I will present evidence originating from published histopathologic and histobacteriologic investigations. The recurrent observation is that adverse pulpal reactions invariably occur - with or without clinical symptoms - when bacteria are left in the cavity. Conversely, uninflamed pulp tissue is observed exclusively in the absence of bacteria in the cavity floor. See more

1. The controversy concerning the depth of caries excavation: the myths and the facts The practice of completely excavating the soft tissue until hard sound den...tin before placing a restoration, has been challenged over the last 25-30 years by a new perspectives and a significant change in philosophical views, i.e. the so-called selective or partial caries excavation. The proponents of these relatively new treatment directives still constitute a minority in the dental world, compared to those who recommend complete excavation of the carious tissue, now referred to as non-selective caries excavation. The former gave rise to an international worldwide group that includes cariologists, researchers, and clinicians who are publishing extensively in the international literature. Their concepts are pushed in a pretty aggressive way, culminating in the statement that nowadays non-selective excavation has to be considered overtreatment and no longer advocated (Schwendicke et al 2016). The fact that endodontists started to accept this position raises serious concern. In fact, the European Society of Endodontology (ESE) has produced a recent position statement in which selective carious tissue removal is advocated in teeth with reversible pulpitis (Duncan et al 2019). The fact that endodontists accept bacteria over the pulp sounds astonishing, considering that they are specialists who routinely treat the pulpal and periapical complications of dentinal infection. In this series of posts, I will critically analyze all the statements made by the proponents of selective caries excavation, on the bases of both basic clinical observations and scientific data originating from histopathologic and histobacteriologic investigations. See more

I've had a few requests from people to share this. It's a hack I found online to get a better fit for your regular surgical masks (if you don't have access to N95s). Hope this helps some of my healthcare friends out there! #yesmyhairispink #boreddentistoverhere #CaroleMASKin

We fell asleep in one world, and woke up in another. Suddenly Disney is out of magic, Paris is no longer romantic, New York doesn't stand up anymore, the Chines...e wall is no longer a fortress, and Mecca is empty. Hugs & kisses suddenly become weapons, and not visiting parents & friends becomes an act of love. Suddenly you realise that power, beauty & money are worthless, and can't get you the oxygen you're fighting for. The world continues its life and it is beautiful. It only puts humans in cages. I think it's sending us a message: You are not necessary. The air, earth, water and sky are fine without you. When you come back, remember that you are just guests in this world not masters."

Failing partial pulpotomy procedure When after meticulous examination of a tooth with a deep carious lesion, the clinical diagnosis of irreversible pulpitis... is made, a necrotic area of varying extension, colonized by bacteria has to be anticipated in the pulp chamber. The extent of this degeneration cannot be established on the basis of clinical signs and symptoms (see my post VPT 4 Partial pulpotomy), but can only be ascertained after surgical access and magnified view. The rationale of the recommended partial pulpotomy protocol is to progressively remove layers of pulp tissue with the objective to locate the front of infection and create a surgical wound in a non-infected pulp tissue. No pulp healing is expected to occur in the presence of infection, and the goal is elimination of the infected tissues. When a clean wound is obtained, this can be covered with a biocompatible and possibly bioactive material. I have previously listed the visual characteristic of an ideal wound: a continuous, blood-filled tissue, with no yellowish or dark areas. This is certainly not an easy task for clinicians and requires deep knowledge of the pulp pathologic dynamics and considerable skill. The guidelines that I am proposing (together with my co-workers) were the result of a learning and refinement process over the years based on histological, histobacteriological and clinical observations. This means that we all learn from failures if we are really observant. In this video I am documenting a case where the pulpotomy procedure was completed at a certain level only because hemostasis was obtained in a short time. However, according to the protocols herein proposed, the aspect of the pulpotomized tissue should have advised against the completion of the procedure at that level. In fact, the wound was not regular and blood-filled, with a yellowish area highly indicative of coagulation necrosis. The obvious consequences were that bacteria left in the pulp caused continuation of pulp inflammation and progression of the pulp degeneration process. The procedure failed after 5 months and root canal treatment was necessary. See more

recent comprehensive AAE article

Partial pulpotomy in two maxillary premolars After discussing the histologic/histobacteriologic bases, as well as clinical aspects of pulpotomy, I am now postin...g a series of videos showing the recommended clinical procedures. The first video deals with successful partial pulpotomy procedures in two maxillary premolars with the diagnosis of irreversible pulpitis. As I had explained before, you will see that successive layers of the superficial pulp were shaved off, until a pulp wound with ideal characteristics was obtained, i.e. a continuous blood-filled tissue surrounded by sound dentin. The pulp wounds were capped with a premixed tricalcium silicate based compound, and the cavities re-accessed after 3 months. This showed that the wounds were repaired with a mineralized tissue, isolating the pulps. The management of these two teeth demonstrates that the knowledge of pulp pathology dynamics, together with the adoption of adequate microsurgical techniques and the use of biocompatible/bioactive materials, allow to maintain the vitality of the majority of the pulp tissue, in cases that were only treated with pulpectomy in the recent past. Enjoy! See more

4. Partial pulpotomy In the previous posts I recommended that only teeth with the diagnosis of reversible pulp inflammation can be successfully managed with dir...ect pulp capping procedures. To date, there is an overall consensus on this point. The diagnosis of irreversible pulpitis in mature teeth is a contraindication for a direct pulp capping procedure. According to international endodontic associations (AAE, Glossary of Endodontic Terms, 9th ed., 2015) these teeth should be treated with nonsurgical root canal therapy. Contrary to this deep-rooted professional dictum, studies published before the 2000s and more recent studies have reported successful outcomes when pulpotomy was performed in cariously exposed pulps of vital teeth that were presented with the signs and symptoms of irreversible pulpitis. However, confusion exists in the literature in terms of the indication and rationale for each VPT treatment modality. In some studies, these treatment procedures were performed interchangeably, without consideration of the pathological status of the remaining pulp tissue. In other studies, the treatment modality was chosen without consideration of the clinical diagnosis, and without explaining why one procedure was preferred over the others. Consequently, information provided by systematic reviews concerning the outcome of the various VPT procedures is inconclusive at the moment. The objective of the present post is to elucidate the indications for partial pulpotomy, based on histologic and histobacteriologic observations, and on a large number of treatments followed-up in the long-term. To overcome the existing confusion, new clinical strategies aimed at identifying intraoperatively the localization of the front of infection are proposed. The recommended guidelines are the result of a learning and refinement process over the last 30 years. This post will be followed by a series of videos illustrating the proposed clinical protocols. Readers are referred to the following publications. Ricucci D, Loghin S, Siqueira JF Jr. Correlation between clinical and histologic pulp diagnoses. J Endod 2014; 40:1932-9. Ricucci D, Loghin S, Lin L, Spångberg LSW, Tay F. Is hard tissue formation in the dental pulp after the death of the primary odontoblasts a regenerative or a reparative process? J Dent 2014; 42:1156-70. Ricucci D, Siqueira JF Jr, Li Y, Tay FR. Vital pulp therapy: histopathology and histobacteriology-based guidelines to treat teeth with deep caries and pulp exposure. J Dent 2019; 86:41-52. Ricucci D, Grande NM, Plotino G, Tay FR. Histologic response of human pulp and periapical tissues to tricalcium silicate-based materials - a series of successfully treated cases. J Endod 2020; 46:307-17.

3. Failures of direct pulp capping In the previous post I discussed the correct indications for direct pulp capping, the clinical and radiographic appearance of... the cases with successful outcome, and the histologic features observed in healed cases. In the present post I am analyzing the reasons for the failures of direct pulp capping. It will be clear that infection is what counts. No pulp healing is expected to occur in the presence of infection, and the goal is elimination of the infected tissues, as well as protection of the uninfected pulp wound with biocompatible and potentially bioactive dental materials. I am insisting on the importance to carefully observe the appearance of the exposed pulp tissue, because this can be correlated to its microbiological status. The guidelines proposed in this series of posts are the result of a learning and refinement process over the years based on histological, histobacteriological and clinical observations. I am showing cases that help explain why a fraction of the direct pulp capping cases performed in the past was doomed to failure. Readers are referred to the following publications. Ricucci D, Loghin S, Siqueira JF Jr. Correlation between clinical and histologic pulp diagnoses. J Endod 2014; 40:1932-9. Ricucci D, Loghin S, Lin L, Spångberg LSW, Tay F. Is hard tissue formation in the dental pulp after the death of the primary odontoblasts a regenerative or a reparative process? J Dent 2014; 42:1156-70. Ricucci D, Siqueira JF Jr, Li Y, Tay FR. Vital pulp therapy: histopathology and histobacteriology-based guidelines to treat teeth with deep caries and pulp exposure. J Dent 2019; 86:41-52. Ricucci D, Grande NM, Plotino G, Tay FR. Histologic response of human pulp and periapical tissues to tricalcium silicate-based materials - a series of successfully treated cases. J Endod 2020; 46:307-17.

2. Deep caries with clinical pulp exposure. In the previous post I discussed the biological bases to treat deep caries without pulp exposure. In this post I am... discussing all those clinical situations in which, despite the clinical diagnosis of reversible pulp inflammation, a pulp exposure is revealed during caries excavation. Many clinicians erroneously believe that an exposed pulp is a condemned pulp. Many patients are suffering because too many teeth today are unnecessarily root canal treated. This belief originates from previous studies reporting very low success rate after direct pulp capping. These studies shall be critically reviewed. I am presenting the relevant histologic/histobacteriologic facts and their correlations with the various clinical conditions, to help clinicians recognising those cases where the pulp vitality can be maintained through a direct pulp capping procedure. It has to be clearly stated that, fundamentally, the teeth that can be subjected to direct pulp capping are those where the clinical diagnosis is reversible pulp inflammation. This means that bacteria have supposedly not entered the pulp space yet. The maximum of care is recommended, through a thorough clinical examination, collecting the clinical story, taking perfect radiographs, and using all the available sensibility tests. Caution is always advised in the diagnosis because, despite the good correlation between clinical and histologic pulp diagnoses, still we do not reach 100% success in our diagnostic evaluation. Not to mention that some pulps undergo necrosis without any clinical symptoms. Therefore, there is still a need for refined and improved means for reliable pulp diagnosis. Like in the previous post, I am insisting on the fact that, contrary to the conclusions of recent publications, the final treatment plan cannot be established on the basis of clinical examination alone, but requires access to the deepest part of the carious lesion. Once again, readers are referred to the following publications. Ricucci D, Loghin S, Siqueira JF Jr. Correlation between clinical and histologic pulp diagnoses. J Endod 2014; 40:1932-9. Ricucci D, Loghin S, Lin L, Spångberg LSW, Tay F. Is hard tissue formation in the dental pulp after the death of the primary odontoblasts a regenerative or a reparative process? J Dent 2014; 42:1156-70. Ricucci D, Siqueira JF Jr, Li Y, Tay FR. Vital pulp therapy: histopathology and histobacteriology-based guidelines to treat teeth with deep caries and pulp exposure. J Dent 2019; 86:41-52. Ricucci D, Grande NM, Plotino G, Tay FR. Histologic response of human pulp and periapical tissues to tricalcium silicate-based materials - a series of successfully treated cases. J Endod 2020; 46:307-17.

Vital Pulp Therapy. Is maintaining pulp vitality a realistic objective in teeth with deep caries and pulp exposure? 1. Deep caries with no clinical pulp exposur...e. Clinicians are often faced with a dilemma in the treatment of deep caries that approximate the pulp chamber in vital teeth with closed apices: whether the dental pulp should be preserved to maintain vitality or completely removed to prevent necrosis, infection, and induction of apical periodontitis. Vital pulp therapy (VPT), a category of prospective treatment modalities that include direct pulp capping, partial pulpotomy and full pulpotomy, has not been favoured by the majority of clinicians until recently. Concerns on the unreliability of these treatment measures were mostly based on the suboptimal results derived from some past follow-up studies. Confusion exists in the literature in terms of the indication and rationale for each VPT treatment modality. In an effort to eliminate, or at least reduce this confusion, the purpose of this series of posts is to discuss first the histopathological and histobacteriological bases of caries disease, focusing on the progression of pulp degeneration, and then to provide clinical recommendations, elucidating the indications for each VPT treatment modality. These recommendations are based on extensive research concerning tissue response to caries, histopathologic and histobacteriologic aspects in dentin caries, diagnosis of the pulp inflammatory state, long-term clinical studies. For detailed information, readers are referred to the following publications. Ricucci D, Loghin S, Siqueira JF Jr. Correlation between clinical and histologic pulp diagnoses. J Endod 2014; 40:1932-9. Ricucci D, Loghin S, Lin L, Spångberg LSW, Tay F. Is hard tissue formation in the dental pulp after the death of the primary odontoblasts a regenerative or a reparative process? J Dent 2014; 42:1156-70. Ricucci D, Siqueira JF Jr, Li Y, Tay FR. Vital pulp therapy: histopathology and histobacteriology-based guidelines to treat teeth with deep caries and pulp exposure. J Dent 2019; 86:41-52. Ricucci D, Grande NM, Plotino G, Tay FR. Histologic response of human pulp and periapical tissues to tricalcium silicate-based materials - a series of successfully treated cases. J Endod 2020; 46:307-17.

I am glad to share with colleagues and friends my last article, produced with my co-authors Nicola Grande, Gianluca Plotino, Franklin Tay, and published in the ...last issue of Journal of Endodontics. The article can be downloaded clicking on the following link before March 12, 2020. No sign up, registration or fees are required. https://authors.elsevier.com/a/1aRppMa8O8qwC This is the first study reporting human tissue response after successful clinical procedures employing premixed tricalcium silicate materials. It is a case series describing histological and histobacteriological findings of three human teeth that had undergone pulpotomy, orthograde retreatment and apicoectomy/root-end filling. Biopsies were obtained because of circumstances that are as infrequent as a blue moon. Confirmation of the biocompatibility and bioactivity of the tricalcium silicate-based materials employed in treating the cases reported in this series enables clinicians to use these materials in confidence for placing them in direct contact with pulpal and periapical tissues. Enjoy reading it! See more