The goal of modern dentistry has shifted from extraction to preservation, aiming to keep natural teeth functional for a lifetime. When faced with severe damage, many people worry that removal is the only option. However, advancements in materials and techniques allow professionals to save teeth that would have been deemed lost decades ago. Understanding the limits of these procedures helps patients make informed decisions about salvaging a damaged tooth. The ability to save a tooth depends less on the initial appearance of the damage and more on the integrity of the underlying biological structures.
Deep Decay and Internal Infection
Deep decay progresses through the hard enamel and dentin layers to reach the soft, innermost pulp tissue. Once the decay breaches the pulp, which contains the nerves and blood vessels, it causes an infection known as pulpitis. This infection often leads to severe, persistent throbbing pain and can eventually spread beyond the root tip, forming an abscess in the jawbone.
Even with infection extending into the surrounding bone, the tooth is frequently salvageable through endodontic treatment, commonly known as a root canal. This procedure involves removing the infected pulp tissue, cleaning and disinfecting the internal chambers, and then sealing the space to prevent reinfection. The presence of an abscess means the infection has exited the tooth, but the root structure remains a viable anchor.
A last-resort procedure for persistent infection is an apicoectomy, where the tip of the root and surrounding infected tissue are surgically removed. The tooth can be saved as long as the majority of the root remains structurally sound and enough surrounding bone is present for support.
Repairing Severe Fractures and Trauma
Structural damage from physical trauma, chips, or cracks presents challenges different from decay. Cracks that only affect the outer enamel and dentin layers can usually be repaired with simple dental bonding or a filling. Cracks that extend deep into the tooth structure require more extensive intervention to prevent the crack from spreading further.
When a large portion of the tooth crown is missing, the remaining structure can often be rebuilt to support a full-coverage crown. This process may involve placing a post and core assembly into the root canal space to provide a stable foundation for the restoration. The success of this repair depends on the fracture line staying above or being treatable at the level of the gum and bone.
A significant biological constraint is maintaining the “biologic width,” the space required for the healthy attachment of gum tissue to the tooth and bone. If a fracture extends too far below the bone level, it violates this space, leading to chronic inflammation and instability. Procedures like surgical crown lengthening or orthodontic extrusion may be performed to expose enough sound tooth structure to place a restoration without compromising gum health.
Conditions Where Restoration Is Impossible
While dentistry has remarkable salvage capabilities, there are definitive boundaries where extraction becomes the only safe option. One of the clearest contraindications is a vertical root fracture, which runs lengthwise along the root. Unlike horizontal fractures, a vertical fracture cannot be predictably sealed, creating a pathway for bacteria to leak into the surrounding tissues.
A tooth also becomes non-restorable when there is an insufficient amount of sound structure remaining above the bone level to support any type of restoration. If decay or fracture extends too deeply below the gum line, it may be impossible to isolate the area for proper bonding, or the resulting restoration would violate the biologic width. If less than 4 millimeters of tooth structure cannot be exposed above the bone, the prognosis is poor.
Severe periodontal disease can also doom a tooth, regardless of the health of its crown or root canal status. Periodontal disease causes bone loss around the roots, stripping the tooth of its foundational support. When bone loss is so extensive that the tooth exhibits Grade 3 mobility, meaning it can be moved horizontally and vertically, the tooth cannot be stabilized and extraction is necessary.
Long-Term Outlook for Saved Teeth
Teeth that have undergone major restorative procedures, such as root canals followed by a crown, often have an excellent long-term prognosis. Studies show that a high percentage of root canal-treated teeth remain healthy and functional decades after the initial procedure. Teeth that receive both a root canal and a crown can last approximately 20 years or more.
A tooth’s longevity is heavily influenced by the placement of a final protective crown, as root-canaled teeth can become brittle without the covering. Teeth without a crown after endodontic treatment are significantly more likely to be lost compared to those that are properly crowned. Ongoing maintenance is also important, including diligent hygiene, avoiding hard foods that could cause fracture, and regular follow-up appointments.
While a saved tooth is not invincible, the goal is to maintain function for as long as possible. The need for re-treatment may arise if decay occurs around the crown margin or if an infection recurs, but even in those cases, the tooth may be saved again.