{"id":6582,"date":"2026-06-01T12:14:50","date_gmt":"2026-06-01T10:14:50","guid":{"rendered":"https:\/\/magazine.zhermack.com\/?p=6582"},"modified":"2026-06-01T12:15:37","modified_gmt":"2026-06-01T10:15:37","slug":"tooth-fractures-classification-prognosis-treatment","status":"publish","type":"post","link":"https:\/\/magazine.zhermack.com\/en\/studio-en\/tooth-fractures-classification-prognosis-treatment\/","title":{"rendered":"Tooth fractures: classification, prognosis, and treatment"},"content":{"rendered":"\n

A tooth fracture is a pathological condition that may affect one or more teeth. Diagnosis can be extremely straightforward and obvious, or as complex and elusive. If the fracture results from trauma<\/strong>, it is often easier to identify, define, and treat.<\/p>\n\n\n\n

By contrast, when a fracture spreads in a subtle way<\/strong> from a very fine fracture line, symptoms may be highly variable, or even subclinical.<\/p>\n\n\n\n

Tooth fractures: classification and clinical presentation<\/h2>\n\n\n\n

There are horizontal and vertical tooth fractures<\/strong>: horizontal fractures often result from a traumatic event, while vertical fractures may have a multifactorial cause and are on average more complex to diagnose and treat.<\/p>\n\n\n\n

The management of horizontal tooth fractures<\/strong> of traumatic origin is a topic that has been sufficiently developed and codified in the literature; prognostic, follow-up, and treatment decision-making schemes exist for both primary teeth and for permanent teeth. (1)<\/p>\n\n\n\n

For the skilled clinician, therefore, they should not pose a particularly complex diagnostic and therapeutic challenge. The clinical presentation is often clear, as are the associated symptoms.<\/p>\n\n\n\n

The clinical presentation and associated symptoms of longitudinal or vertical tooth fractures<\/strong> are far more complex, more insidious, and more variable. (2)<\/p>\n\n\n\n

The term longitudinal fracture is more correct because it implies a vertical dimension of the fracture and a temporal dimension. (3)<\/p>\n\n\n\n

Some longitudinal tooth fractures are simple to diagnose and treat, while others are complex, and progress so severely that extraction of the tooth becomes necessary. (2)<\/p>\n\n\n\n

The relative absence of robust support in literature must also be considered: the available studies are few, and evidence is scarce. For these reasons, establishing an appropriate treatment plan<\/strong> and organising careful follow-up have traditionally relied on the operator’s experience and anecdotal opinions. (2) <\/p>\n\n\n\n

Classification of longitudinal tooth fractures<\/h3>\n\n\n\n

Longitudinal tooth fractures<\/strong> can involve all teeth<\/strong> and may be caused by occlusal stresses, whether or not associated with dental rehabilitations.<\/p>\n\n\n\n

They may be classified according to severity into five categories<\/strong> (3):<\/p>\n\n\n\n

    \n
  1. Craze lines<\/li>\n\n\n\n
  2. Fractured cusps<\/li>\n\n\n\n
  3. Cracked tooth<\/li>\n\n\n\n
  4. Split tooth<\/li>\n\n\n\n
  5. Vertical root fractures<\/li>\n<\/ol>\n\n\n\n

    This classification should facilitate accurate identification of the fracture types<\/strong>, helping researchers develop new scientific material, and assisting clinicians in diagnosing and managing the fracture correctly. (4-6)<\/p>\n\n\n\n

    Clinical aspects of longitudinal tooth fractures<\/h4>\n\n\n\n
      \n
    1. Fractures are usually caused by the application of excessive forces sustained<\/strong> over time.<\/li>\n\n\n\n
    2. Initially, they may be almost invisible<\/strong> and imperceptible, slowly becoming more observable as the crack expands. They may also be subgingival and difficult to observe, even after raising a flap.<\/li>\n\n\n\n
    3. As the crack opens, pigmentations<\/strong> may occur.<\/li>\n\n\n\n
    4. A small fracture may remain stable over time<\/strong>, extend slowly, or widen quickly.<\/li>\n\n\n\n
    5. Signs and symptoms may be entirely absent at first <\/strong>but appear months, years, or even decades after the problem is first identified.<\/li>\n\n\n\n
    6. Longitudinal tooth fractures are often clinical findings, rather than diagnostic findings. The fracture may or may not involve the pulp tissue.<\/li>\n<\/ol>\n\n\n\n

      Enamel craze lines<\/h3>\n\n\n\n

      Crack lines are common in adults. These lines are confined to the thickness of the enamel. These lines rarely herald deeper fractures. They can cause confusion when identified on the distal or mesial margins of the posterior teeth.<\/p>\n\n\n\n

      Fractured cusp<\/h3>\n\n\n\n

      In a fractured cusp, the lack of adequate dentinal support<\/strong> for the enamel of the cusp may cause the cusp to break, with fracture lines sometimes extending to subgingival margins.<\/p>\n\n\n\n

      This type of fracture commonly occurs in teeth with extensive restorations<\/strong> or extensive undermined carious lesions. (8) Treatment involves removal of the fractured portion and conservative\/prosthetic restoration of the tooth.<\/p>\n\n\n\n

      Incomplete tooth fracture (cracked tooth)<\/h3>\n\n\n\n

      A tooth fracture is defined as an incomplete coronal fracture<\/strong> with subgingival extension, and may involve one or both margins (mesial and distal). This type of fracture is also referred to as a greenstick-type<\/strong> fracture. (7.12)<\/p>\n\n\n\n

      It is a type of fracture usually centred on the long, mesiodistal axis of the tooth<\/strong>, and is therefore dangerously directed towards the tooth’s pulp chamber. Only rarely, in mandibular molars, is the fracture line lingual-buccal.<\/p>\n\n\n\n

      The teeth most affected<\/strong> are molars, mandibular molars, and maxillary premolars. (2) The fracture line may extend as far as the pulp chamber. Brachyfacial patients with strong masticatory musculature are usually involved. Radiographs normally show no particular diagnostic signs, and are used only to assess any signs of periapical involvement.<\/p>\n\n\n\n

      Transillumination<\/strong> or methylene blue<\/strong> may be useful for assessing the extent<\/strong>of the fracture. It is often necessary to assess the apical extent of a fracture by opening the tissue slightly with a bur; the fracture line may continue very far apically and, if complete removal became necessary, the tooth could prove non-restorable.<\/p>\n\n\n\n

      It is advisable to verify, by probing with an instrument, that the two fragments divided by the fracture line are not separable. A periodontal probe <\/strong>must be used to look for any isolated point probing defect, a decidedly unfavourable prognostic indicator.<\/p>\n\n\n\n

      Treatment depends essentially on the extent of the fracture<\/strong>, its location and the presence of any pulpal symptoms. In specific cases, it is appropriate to cover the tooth using a crown or a full-cusp-coverage onlay. It is essential to inform the patient of the situation and the future prognosis, which is difficult to define. (2)<\/p>\n\n\n\n

      Split tooth<\/h3>\n\n\n\n

      A split tooth occurs when force applied to the fracture line reveals separation between the two tooth fragments<\/strong>. Often, in such cases, the fracture extends subgingivally.<\/p>\n\n\n\n

      This condition may be the natural progression of an untreated cracked tooth<\/strong>. Diagnosis is similar to that of a simple longitudinal tooth fracture. Symptoms can vary widely, and a typical diagnostic sign is the so-called ‘wedging effect’ when force is applied to the joint line.<\/p>\n\n\n\n

      In these cases, treatment generally involves extraction of the tooth<\/strong>, unless the fracture extends in a direction favourable to removal of one of the two fragments, with subsequent restoration of the remaining fragment.<\/p>\n\n\n\n

      Vertical root fracture<\/h3>\n\n\n\n

      A vertical fracture occurs when the fracture line also extends into the root<\/strong>, running along the periodontal ligament space.<\/p>\n\n\n\n

      Here again, the diagnosis is not straightforward, and the symptoms and signs may be extremely variable. The symptoms reported are often periapical in nature. Once the diagnosis has been confirmed, the only treatment available is extraction of the tooth.<\/p>\n\n\n\n

      In conclusion, extreme care is required during diagnosis when a longitudinal tooth fracture is suspected. All diagnostic records must be taken correctly, the symptoms must be noted and, once diagnosis has been made, the patient should be advised of the potential evolution of the clinical situation.<\/p>\n\n\n\n

      \n\n\n\n

      References:<\/strong><\/p>\n\n\n\n

        \n
      1. Council, O. (2011). Guideline on management of acute dental trauma. Dental Traumatology, 1(3).<\/li>\n\n\n\n
      2. RIVERA, E. M., & WALTON, R. E. (2007). Longitudinal tooth fractures: findings that contribute to complex endodontic diagnoses. Endodontic Topics, 16(1), 82-111.<\/li>\n\n\n\n
      3. Rivera EM, Williamson A. Diagnosis and treatment planning: cracked tooth. Tex Dent J 2003: 120: 278\u2013283.<\/li>\n\n\n\n
      4. Walton RE. Cracked tooth and vertical root fracture.\u00a0 In: Walton RE, Torabinejad M, eds. Principles and Practice of Endodontics, 2nd edn. Philadelphia, PA: W.B. Saunders Company, 1996: 474\u2013492.<\/li>\n\n\n\n
      5. American Association of Endodontists. Cracking the code of the cracked tooth. American Association of Endodontists Colleagues for Excellence, 1997; Fall\/Winter.<\/li>\n\n\n\n
      6. Walton RE, Rivera EM. Longitudinal tooth fractures. In: Walton RE, Torabinejad M, eds. Principles and Practice of Endodontics, second printing, 3rd edn. Philadelphia, PA: W.B. Saunders Company, 2002: 474\u2013492.<\/li>\n\n\n\n
      7. Abou-Rass M. Crack lines: the precursors of tooth fractures \u2013 their diagnosis and treatment. Quintessence Int 1983: 14: 437\u2013447.<\/li>\n\n\n\n
      8. Fennis WM, Kuijs RH, Kreulen CM, Roeters FJ, Creugers NH, Burgersdijk RC. A survey of cusp fractures in a population of general dental practices. Int J Prosthodont 2002: 15: 559\u2013563.<\/li>\n\n\n\n
      9. Hiatt WH. Incomplete crown-root fracture in pulpal\u2013periodontal disease. J Periodontol 1973: 44: 369\u2013379.<\/li>\n\n\n\n
      10. Cameron CE. Cracked-tooth syndrome. J Am Dent Assoc 1964: 68: 405\u2013411.<\/li>\n\n\n\n
      11. Cameron CE. The cracked-tooth syndrome: additional findings. J Am Dent Assoc 1976: 93: 971\u2013975.<\/li>\n\n\n\n
      12. Ailor Jr JE Managing incomplete tooth fractures. J Am Dent Assoc 2000: 131: 1168\u20131174.<\/li>\n<\/ol>\n","protected":false},"excerpt":{"rendered":"

        A tooth fracture is a pathological condition that may affect one or more teeth. Diagnosis can be extremely straightforward and obvious, or as complex and elusive. If the fracture results from trauma, it is often easier to identify, define, and treat. By contrast, when a fracture spreads in a subtle way from a very fine […]<\/p>\n","protected":false},"author":1,"featured_media":6555,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[40],"tags":[],"class_list":["post-6582","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-studio-en"],"acf":[],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/magazine.zhermack.com\/en\/wp-json\/wp\/v2\/posts\/6582","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/magazine.zhermack.com\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/magazine.zhermack.com\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/magazine.zhermack.com\/en\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/magazine.zhermack.com\/en\/wp-json\/wp\/v2\/comments?post=6582"}],"version-history":[{"count":2,"href":"https:\/\/magazine.zhermack.com\/en\/wp-json\/wp\/v2\/posts\/6582\/revisions"}],"predecessor-version":[{"id":6584,"href":"https:\/\/magazine.zhermack.com\/en\/wp-json\/wp\/v2\/posts\/6582\/revisions\/6584"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/magazine.zhermack.com\/en\/wp-json\/wp\/v2\/media\/6555"}],"wp:attachment":[{"href":"https:\/\/magazine.zhermack.com\/en\/wp-json\/wp\/v2\/media?parent=6582"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/magazine.zhermack.com\/en\/wp-json\/wp\/v2\/categories?post=6582"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/magazine.zhermack.com\/en\/wp-json\/wp\/v2\/tags?post=6582"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}