The detection and diagnosis of the TSC is perhaps the most difficult aspect in the management of the cracked, fissured and fractured teeth in dental practice. In this five parts series the 4Rs operational diagnosis protocol(4RsOD) is used as a best dental diagnosis practice.

The protocol was specifically developed to remedy the shortcomings of the conventional Endodontic diagnosis tests.

The protocol helps the clinician to use the skills of: hearing, seeing and acting to accurately learn the patient problem.

The(4Rs OD) protocol provides the clinician with multidisciplinary, systematic approach for collecting, analyzing, and synthesizing the examination data into diagnostic, treatment planning, and prognostic decisions.

The 4Rs OD consists of the followings assessment tests:

In this part of the series we will demonstrate the important role of tooth structure cracks (TSC) in dental practice. It will show how undiagnosed or misdiagnosed tooth cracks can affect or complicate endodontic, periodontic or restorative treatments outcomes.

The program includes detailed histories of 4 substandard endodontically treated that were retreated and restored by general practitioners, and specialists. Either through case history progression or restoration removal, the 4 teeth were found having TSC.

Because of the retrospective nature of the analysis, it was impossible to determine whether the cracks were present prior to treatment and were missed, initiated or propagated during the treatment. What is important in this regard is to focus on the role of the cracks and their effect on the treatment outcome.

After a lengthy history of treatment, retreatment, recall and follow-ups, the 4 teeth were extracted and became teaching cases. each case is retrospectively analyzed its story and history is presented in the webinar.

The webinar presentation is organized to sharpen the dental professionals diagnostic skills, specifically increase their awareness to search for hidden line cracks concealed under crowns and large restorations. Especially Amalgam restorations in teeth planned for full crowns or full coverage restoration.

The lessons learned from these 4 teaching cases, have generated many guiding principles. Here are 3 examples:

• Never do endodontic treatment or retreatment through defective or a mediocre crown.
• The crown or the bridge dentists work hard to save is often the cause of the endodontic or periodontic problem.
• Endodontic surgery is not a substitute for standard endodontic treatment or retreatment.

Clinical management of cracked teeth in dental practice is an area replete with misunderstanding and misinformation. First, the literature lacks prospective studies and clinically useful universal definitions. Second, although cracked teeth problems vary significantly in diagnosis, treatment and prognosis. The literature terminology does not specifically differentiate between “Fractured teeth”, “Cracked teeth”, “Cracked Tooth Syndrome”, “Green stick fractures” and “Incomplete coronal fractures”.

The author’s 3x3 Tooth Structure Cracks (TSC) classification, grouped the various terminologies which relate to the cracked or fractured teeth problems, under one term “Tooth Cracks”. Then defined and classified the “cracks” according to their anatomic, physical and pathologic characteristics.

Physically, “Tooth Cracks” are classified into:

• Line Cracks
• Fissure Cracks
• Fracture Cracks

Anatomically, “Tooth Cracks” are classified into:

• Marginal Ridges
• Grooves
• Surfaces

Pathologically, “Tooth Cracks “are classified into:

• Contributory
• Noncontributory
• Partially Contributory

The webinar presentation shows how to differentiate between the harmless “noncontributory crack” and the harmful “contributory crack”.

Contributory cracks cause reversible and irreversible pulpitis, pulp calcification, pulp necrosis, periapical and periradicular lesions. On the other hand, noncontributory cracks could be microscopically visible microcracks or clinically visible line. These cracks remain at the early initiation or development stages for years. They remain still and stationery, cause no pulpal or periodontal pathology as long as they are not pressured, and stressed by new forces or loads. Forces such as root filling condensation or traumatic fitting of a post.

Updated information about the etiology and initiation mechanism of tooth cracks is presented focusing on:

• Abusive restorative procedures that cause coronal cracks
• Abusive mechanical endodontic procedures that cause radicular cracks
• Abusive post placement procedures
• Dental occlusion factors

Part IV of the series focuses on how to apply the information learned in Part I, II and III of the cracked teeth master class series into clinical patient care.

The 4R Operational Diagnosis protocol is used in the diagnosis of the presented seven symptomatic cracked teeth cases, therefore each of the cases will include the 4R protocol findings profiles for:

1. Patient Pain
2. Ten Areas of Diagnostic Interest radiographic interpretation
3. Pulp response
4. Periodontal response
5. Crown structure
6. Pulp chamber content
7. Canal content

A common diagnostic imaging finding in posterior cracked teeth, is pulp chamber opacity. Pulp Stones, denticles and calcific chamber recession are considered cardinal signs of the pathology commonly called pulpal calcification. the opacity is principally observed in unrestored, posterior cracked teeth or teeth with defective restorations, chronic caries and bacterial leakage.

Pulp calcification has detrimental effects on the dental pulp recovery from injury abilities and response to testing stimuli. Furthermore, it is known to complicate the endodontic treatment procedures. Because of its importance as diagnostic and the treatment risk factor, a special segment on the of pulpal calcification is featured in the introduction.

The 7-cases reviewed in the webinar represent an excellent sampling of the symptomatic cracked teeth cases encountered in general dental practices. Dr. Abou-Rass explains his guiding principles, clinical and biological rationales used in the treatment of each case.

The cases are as follows:

In the introduction of the program, the author reveals an alarming 24%-60% global prevalence of Apical lesions in teeth with inadequate root canal treatment. The literature’s histopathologic term used in describing these lesions is Apical Periodontitis. (AP). The statistics are alarming because the “Standard Normal” prevalence of Apical lesions in endodontically untreated teeth is 1½% - 7%.

This program stands for the management of teeth with substandard endodontic treatment failures because of the evidence-based relationship between abusive endodontic treatment, and root structure cracks initiation and propagation. Abusive endodontic treatment is one form and a principal cause of substandard endodontic treatment. More on this relationship discussed in part III of the master class series.

The program is composed of seven chapters planned to include the most clinically relevant facets of the inadequate or sub-standard endodontic treatment.

Pulpal necrosis and substandard endodontic treatment are the principal causes of Apical Periodontitis. Mechanical root canal preparation is an integral part of modern endodontic practice. The improper use of mechanical or manual endodontic instruments causes root canal ledging, stripping, perforating and instrument breakage. These errors cause incomplete root filling which is the leading cause of substandard endodontic treatment outcomes. Collectively about 80% of endodontic treatment failures are contributed to root canal preparation errors.

To correct canal preparation errors, the clinician uses manual, mechanical tools and gadgets to bypass a root canal ledge or broken instrument. The generated forces associated with these attempts may initiate within the root canal surfaces micro cracks or propagate existing ones. The clinical complications of these cracks usually manifest months or years following endodontic treatment and post placement completion.

Therefore, regardless of the patient signs and symptoms, the radiographic diagnosis of a tooth with substandard endodontic treatment, should be considered a dental treatment risk factor. The clinician should investigate the tooth when considering endodontic retreatment or plan to use the previous root canal filling as a foundation for a post placement or new restoration.

Chapter 6 outlines the procedural protocol to follow when treating patients with substandard endodontically treated teeth. The clinician’s objectives are:

1. Establish a doctor–patient relationship based on considerate interaction especially when the patient is unaware of having an iatrogenic dental problem.
2. Identify and correct the cause of the substandard treatment.
3. Rule out the presence of line cracks in the pulp chamber or the clinical crown before endodontic or restorative retreatment.
4. Prevent tooth crack propagation thru changing the treatment protocol to atraumatic endodontic and restorative retreatment.

The program contains advanced specialty knowledge that enhances the clinician diagnostic and treatment skills. The general practitioners need such knowledge because they perform 72%- 88% of endodontic treatments services provided in the USA and Canada.

Chapter five discusses the role of the dental school as an important influencing factor in resolving the problem of substandard endodontic treatment. Endodontic curricula must have additional instructional hours’ time. Need to focus on more relevant content presented by full-time endodontic faculty committed only to the undergraduate curriculum and advanced continuing education courses to the general practitioners.

This program offers concepts, methods and guiding principles based on evidence, and tested clinical practices. The goal is to enhance the clinicians understanding of endodontic treatment diagnostics and the relationship between endodontic treatment and tooth structure cracks.