Treatment of Primary Teeth with Apical Periodontitis. Pulpectomy protocol. Errors and Complications

Treatment of Primary Teeth with Apical Periodontitis. Pulpectomy protocol. Errors and Complications

Despite significant advancements and the implementation of comprehensive caries prevention programs, premature loss of both primary and permanent teeth in children remains a pressing issue. Among primary teeth, the leading cause of early extraction is apical periodontitis. Such premature tooth loss can precipitate malocclusion, disrupt chewing and speech functions, and contribute to adverse psychological effects.

Endodontic treatment in primary teeth is tailored to the root’s developmental status. For fully developed roots, complete endodontic therapy is recommended, while early-stage root resorption necessitates modified techniques, such as the deep pulpotomy approach. Surgical extraction of primary teeth is associated with early tooth loss, often leading to dentoalveolar anomalies and impaired occlusal development. In contrast, conservative therapy, if not meticulously executed with appropriate radiographic support, may result in complications like cyst formation, developmental defects, or malpositioned permanent teeth.

Effective management of apical periodontitis in primary teeth requires careful evaluation and a thorough understanding of the treatment prognosis. Before initiating treatment, it is crucial to assess various factors that can influence the success of endodontic interventions. This ensures a more predictable outcome and informed decision-making, both for clinicians and patients. If you are seeking to enhance your skills in endodontic treatment planning and evaluation join the lesson "Success in Endodontics: Predicting" and gain valuable insights!

The development of apical periodontitis is often linked to inappropriate or poorly executed attempts at preserving pulp vitality (partial or total). Misjudgment of caries severity, the child’s health, or technical deviations from established protocols can exacerbate these conditions. Moreover, pulp devitalization treatments, if improperly performed—such as inadequate cavity preparation or the hasty use of mummifying agents—may provoke apical periodontitis.

The nuanced understanding of periodontal and endodontic dynamics in pediatric dentistry underscores the importance of precise diagnostic and therapeutic interventions to mitigate complications and support optimal dental development.

When selecting a treatment method, clinicians must evaluate:

• The child’s age and health status: These provide context but are not definitive in determining treatment.
• Tooth anatomy: The condition of the crown, root (integrity and the stage of resorption), and the extent of inflammatory damage are critical considerations.
• State of the permanent tooth germ: This includes ensuring proper development without interference from infections in the primary tooth.
• Inflammatory progression: Chronic periodontitis disrupts normal root resorption patterns, which may be accelerated or delayed based on apical tissue conditions.
• Psychosocial aspects: The child’s emotional and psychological state is pivotal in determining the approach, especially in younger patients.

Chronic inflammation can alter the natural progression of root resorption in primary teeth, either accelerating or delaying the process. Importantly, root formation may be compromised well before clinical symptoms become evident. Thus, while age is not the definitive factor in managing chronic periodontitis, it provides a timeline for the expected physiological tooth replacement.

​​Certain conditions warrant the extraction of primary teeth, such as:

• Root resorption of 50% or more,
• Imminent natural exfoliation within 18 months,
• Delayed root resorption obstructing permanent tooth eruption,
• Functional irrelevance of the tooth,
• Systemic conditions contraindicating endodontic therapy,
• Recurrent failure of prior treatments,
• Risk of spreading inflammation,
• Perforation of the tooth chamber floor, and
• Pathological processes threatening adjacent permanent teeth or tooth buds.

Radiographic evidence is essential in identifying cortical plate damage or significant pathological progression.

Conservative Endodontic Therapy

Conservative treatment aims to:

1. Resolve periodontal inflammation,
2. Preserve physiological root resorption or formation,
3. Restore bone structure and maintain the tooth’s function until natural exfoliation.

Key Principles:

• Pain management is fundamental, necessitating skillful administration of local anesthesia tailored to anatomical variations in children.
• Careful access preparation minimizes structural damage, accounting for the large pulp chambers and thin dentinal walls of primary teeth.
• Chemical disinfection with non-irritating antiseptics prevents injury to permanent tooth buds.
• Biodegradable materials for canal obturation ensure compatibility with the natural resorption process.

Stages of Pulpectomy Treatment

1. Establishing Endodontic Access
Access cavities for anterior teeth, both primary and permanent, are traditionally created on the oral surface, with an exception for maxillary central incisors. For primary incisors a vestibular approach is recommended, followed by composite restoration or a full-crown placement. This approach involves greater extension towards the incisal edge for optimal straight-line access to the canal.

For primary molars and permanent teeth, endodontic access is similar, but it is essential to account for differences in anatomy. Primary molars have shorter crowns and reduced distances from the occlusal surface to the pulp chamber floor, making care necessary to avoid perforation. A round bur is used to remove the tooth's roof and dentin over canal orifices. However, the shorter crowns of primary molars and the reduced distance from the occlusal surface to the pulp floor must be considered to avoid perforation.

2. Pulp Extirpation and Canal Preparation
The removal of necrotic pulp and subsequent canal preparation in primary teeth follow similar principles to permanent teeth, with specific adjustments. The necrotic pulp is removed in stages using a pulp extractor or H-file, with the canal immersed in an antiseptic bath.

• Preferred Technique: The crown-down method minimizes the risk of pushing infected material beyond the apex. Employ this technique, forming an apical stop at the working length while exercising caution to avoid perforation and respecting the thin canal walls.
• Working Length: Initially estimated based on radiographic and average root lengths, it is finalized post-pulp removal. In children, working length is set 2–3 mm shorter than the radiographic length to prevent damage to developing permanent teeth and extrusion of filling material. Such precautions are taken particularly in teeth with resorbing roots where the apical foramen migrates coronally. Moreover, tapering of canals is minimized to prevent unnecessary structural weakening.
• Instrumentation: Larger manual instruments are used for canal shaping, as Gates-Glidden burs pose a perforation risk. Opinions on optimal canal diameter vary, but minimal mechanical preparation is often favored, complemented by extensive chemical cleaning.
• Granulation tissue management: Granulation tissue in the canals is anesthetized with 10% lidocaine and removed mechanically (e.g., using excavators or H-files) or chemically cauterized with phenol-formaldehyde solutions or other appropriate agents.
• Irrigation protocol: Due to the complexity of primary tooth canal anatomy (e.g., apical branches, lateral canals), thorough irrigation is crucial. Recommended irrigants include:
  • Sodium hypochlorite to dissolve necrotic tissue,
  • 3% hydrogen peroxide for mechanical cleansing and oxidation,
  • Chlorhexidine (0.2–2%) for its antibacterial properties, and
  • 10% povidone-iodine for infected cases with uncertain prognosis.

The canals are dried with paper points, ensuring complete removal of debris and irrigants.

3. Canal Filling in Primary Teeth
The ideal filling material for primary teeth canals should:

• Resorb alongside the roots,
• Be non-toxic to periapical tissues and permanent tooth buds,
• Adapt well to canal walls,
• Exhibit radiopacity, minimal shrinkage, and ease of removal.

Root canals are filled manually with pastes delivered via K-files or smaller filling tools. The paste should remain within canal boundaries, using resorbable materials that degrade alongside the primary tooth root.

Zinc oxide-eugenol paste is commonly used, applied manually or with a filling carrier. Alternatives include calcium hydroxide-based or iodoform-containing pastes.

Non-resorbable materials like gutta-percha are reserved for cases where missing permanent tooth buds necessitate prolonged retention of primary teeth.

4. Restoration of Primary Teeth
To prevent fractures, stainless steel crowns are recommended for molars after endodontic treatment. Composite or prefabricated crowns (e.g., with vestibular windows) are suitable for incisors and canines.

5. Monitoring and Success Criteria
The outcomes of endodontic treatment for primary teeth with apical periodontitis should be monitored at intervals of 6 and 12 months. The success of the treatment is assessed through both clinical and radiographic criteria:

Clinical Evaluation

• Maintenance of the tooth's function without discomfort,
• Absence of pain, redness, swelling, sinus tracts, or increased mobility.

Radiographic Indicators

• Continued development of the permanent tooth follicle,
• Regeneration of bone tissue in the furcation and periapical regions,
• Lack of pathological root resorption in the treated primary tooth,
• Alignment of root resorption timing with physiological resorption typical of vital primary teeth.

If a positive trend is observed at the 12-month follow-up, no further monitoring is needed, and the patient may be discharged from regular observation. Conversely, if the pathological process advances, tooth extraction is recommended, followed by monitoring of the affected site.

One-Visit Protocols:
For chronic apical periodontitis or abscesses without acute symptoms, one-visit pulpectomy can save time, provided canal disinfection is adequate.

Extended Antiseptic Treatment:
For cases with persistent infection, a multi-visit approach includes prolonged antiseptic irrigation between visits, followed by canal filling and restoration.

Modern endodontics is evolving rapidly, with new tools, methods, and evidence-based protocols redefining how we deliver care. In this article, we’ve focused on one essential method of pulp therapy – pulpectomy. However, if you’re eager to stay ahead in endodontic practice and learn the most cutting-edge techniques across the entire treatment spectrum, our course “What’s NEW in Endodontics: From Anesthesia to Obturation” is the perfect opportunity for you!

Errors and Complications in the Treatment

1. Diagnostic Errors
   • Cause: Misinterpretation of radiographs, such as mistaking growth zones, mental or incisal foramina, nasal cavities, or maxillary sinuses for pathological formations.
   • Complication: Incorrect diagnosis leading to an inappropriate treatment plan.
   • Solution: Correlate clinical symptoms with radiographic and electrical diagnostic findings. Consider the unique clinical progression of apical periodontitis in children.
2. Errors in Treatment Planning for Children with Cardiovascular Conditions

• Complication: Increased risk of bacterial endocarditis.
• Solution: Plan preoperative antibiotic prophylaxis for these children. Non-vital primary teeth should be extracted, and endodontic treatment of permanent teeth should only proceed with a favorable prognosis.

       3. Errors in Endodontic Access Preparation

• Too Small Access:
  • Complication: Incomplete debridement, leading to persistent inflammation due to retained organic material or toxins in missed accessory canals.
  • Solution: Extract affected primary teeth if inflammation progresses.
• Too Large Access:
  • Complication: Increased risk of crown or root fracture.
  • Solution: Adjust and reduce weakened cusps. If restoration is unfeasible, extract the tooth.
  • Complication: Perforation of the tooth’s cervical wall or furcation area.
  • Solution: Extract the affected primary tooth.

       4. Improper Instrumentation Technique

• Complication: Instrument fracture within the canal.
• Solution: For primary teeth, if the broken fragment cannot be retrieved, fill the canal up to the level of the fragment and monitor dynamically.

       5. Extrusion of Sodium Hypochlorite Beyond the Root Canal

• Complication: Inflammation and necrosis of periapical tissues.
• Solution: Prescribe analgesics and administer antibiotics to prevent infection of damaged tissues.

       6. Filling Primary Root Canals with Gutta-Percha Points

• Complication: Delayed or arrested root resorption.
• Solution: Monitor dynamically for 6–12 months. Extract the primary tooth when physiological exfoliation is due.

By identifying and addressing these errors, clinicians can minimize complications and optimize treatment outcomes for primary teeth with apical periodontitis.

While treating apical periodontitis in primary teeth is critical for young children, the challenge evolves significantly in teenagers and young adults. As permanent teeth fully develop, apical periodontitis can become a complex condition requiring advanced diagnostic and therapeutic strategies. For many patients in this age group, conservative endodontic treatments may not be sufficient, making apical surgery an essential tool in your clinical repertoire. Our course “Apical surgery: for endodontists and surgeons” is designed to equip you with the skills and confidence to manage these cases effectively, covering both the surgical and restorative aspects.