What is the management approach for over-retained primary teeth in children and adolescents?

Management of Over-Retained Primary Teeth

For over-retained primary teeth, the primary decision is whether to extract or retain the tooth, which depends on the presence of a permanent successor, the child's age, and the functional status of the primary tooth. 1

Initial Assessment

When evaluating an over-retained primary tooth, systematically assess the following:

• Confirm presence or absence of permanent successor tooth using panoramic radiograph - this is the single most critical factor determining management 1, 2
• Evaluate the developmental stage of any permanent successor using Nolla staging (a primary tooth is considered retained when its successor is at Nolla stage 8,9, or 10) 2
• Assess the primary tooth for pathology including dental caries, fillings, root resorption status, and mobility 2
• Determine patient age relative to expected exfoliation timing 3
• Check for ectopic positioning or eruption path abnormalities 4, 2

Management Algorithm

When Permanent Successor is Present

Extract the retained primary tooth to allow spontaneous eruption of the permanent tooth, with timing based on tooth type and patient age: 3

• For retained primary incisors: extract before age 9 years to enable spontaneous permanent tooth eruption 3
• For retained primary canines and molars: extract before age 13 years after radiographic confirmation of the permanent successor 3
• Delayed extraction beyond these age thresholds may necessitate complex orthodontic treatment and prevent spontaneous eruption 3

Important caveat: If the primary tooth root is not resorbing and is blocking permanent tooth eruption, surgical exposure may be needed in addition to extraction 3, 4

When Permanent Successor is Absent (Hypodontia)

Retain the primary tooth as long as it remains functional and asymptomatic: 1, 5

• Primary molars can be retained long-term and serve as functional units for years or decades 1, 5
• Monitor retained primary teeth regularly for signs of pathology including root resorption, mobility, or periapical pathology 5
• Consider restorative enhancement to improve aesthetics and function, including composite buildups, crowns, or other minimally invasive techniques 5
• Plan for eventual replacement when the primary tooth fails (typically with implant, bridge, or orthodontic space closure) 1

Special Circumstances

For impacted primary teeth (not erupted): 4

• If associated with odontomas or other pathology, surgically remove the obstruction and monitor for eruption 4
• Consider surgical exposure with or without orthodontic traction depending on position 4
• Extract if eruption is unlikely even after obstruction removal 4
• Monitor permanent successors long-term as they may be hypoplastic and delayed in development 4

Common Pitfalls to Avoid

• Do not assume absence of permanent successor without radiographic confirmation - 68.7% of retained primary teeth have no identifiable pathological cause, but the successor may still be present 2
• Do not delay extraction indefinitely when a permanent successor exists - this leads to complex orthodontic problems and may prevent spontaneous eruption 3
• Do not routinely extract retained primary teeth in hypodontia cases - these teeth can function well long-term with proper maintenance 1, 5
• Do not ignore pathology in retained primary teeth - dental caries (4.6% of cases) and existing restorations (19.3% of cases) are common and require treatment 2

Monitoring Protocol

For retained primary teeth being observed rather than extracted:

• Schedule regular dental follow-up to monitor for pulpal necrosis signs including gray discoloration, gingival swelling, parulis, or increased mobility 6, 7
• Obtain periodic radiographs to assess root resorption and permanent tooth development 4
• Maintain excellent oral hygiene to optimize tooth longevity 6, 8