Root canal or implant?

Endodontics Root canal or implant? Background.—The foundation of individual risk assessment and determination of long-term prognosis for interventions should be based on evidence from recent data in the literature. Deciding between root canal treatment (RCT) and extraction and replacement with an implant requires careful analysis of all the factors that contribute to its success or failure. However, the literature is inconsistent

with respect to the definitions of success and survival for RCT and implants. Often, more stringent criteria are used to define successful RCT than are employed for implants. Practitioners must also recognize the differences in outcome depending on whether it is considered at implant level or restoration level, which includes both the implant and superstructures (Table 2). Because the outcomes with

Table 2.—Factors Influencing Endodontic and Implant Treatment Outcome Initial RCT

Preoperative

þ Vital pulp tissue  Periapical lesion

Endodontic retreatment

þ Root canal filling >2 mm short of the apex þ No periapical lesion

 Large periapical lesion

Intraoperative

Postoperative

þ Root canal filling with no voids extending to 2 mm within apex (radiographically) þ Sufficient coronal restoration  Missed canals and inadequate cleaning  Errors such as ledging, instrument fracture, root perforations  Inadequate obturation  Root canal filling >2 mm short of the apex or overfill  Restoration failure (coronal leakage)

 Altered root-canal morphology or perforation  Adequate existing root canal filling þ Addressing previous technical shortcomings

þ Adequate root canal filling feasible

Apical surgery

þ Orthograde retreatment feasible þ Significant overfill or root canal filling >2 mm short of the apex  Lesion R5 mm  Persisting lesion despite satisfactory root canal filling  Combined endo-perio lesion  Previous surgical treatment þ Root-end filling

 Poor accessibility

Implant treatment

 Insufficient bone volume  Specific anatomic findings  History of periodontitis  Previous implant failure  Insufficient oral hygiene and smoking (see also Table 3)

þ/ Type of implant and surface

þ/ Type of bone  Fenestration, bone defects  Specific anatomic findings  Bone augmentation  Immediate implant placement

 Restoration failure (coronal leakage, no cuspal coverage)

þ/ No obvious influence by antibiotics

 Wound healing problems  Iatrogenic factors (e.g., excess cement)  Insufficient oral hygiene and smoking  Peri-implantitis

Abbreviations: þ, Positively influencing factors; –, negatively influencing factors. (Courtesy of Zitzmann NU, Krastl G, Hecker H, et al: Endodontics or implants? A review of decisive criteria and guidelines for single tooth restorations and full arch reconstructions. Int Endod J 42:757-774, 2009.)

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implants and RCT are similar, factors in addition to the anticipated outcome must be considered in deciding on treatment. The decisive criteria and a procedure for choosing an endodontic or implant approach based on the best available evidence were offered. Methods.—A MEDLINE search covering data between 1966 and 2008 identified 49 publications that were relevant to the study. Results.—The decision to treat or extract a natural tooth depends more on the overall rehabilitation plan than on the health of the individual tooth. Although implants may offer more predictable and economically feasible options, long-term site-specific and patient-related factors must be critically analyzed to discover risks for

complications and failures that accompany the use of implants (Table 3). RCT outcomes should be evaluated over a period of 4–5 years, so that periapical lesions have an appropriate window to accomplish complete healing (Fig 2). Dental implants need to be observed for at least 5 years for the manifestation of any peri-implant disease. Either RCT or retreatment is the initial treatment of choice unless the tooth is deemed totally unrestorable. In single-tooth restorations, the increased risk associated with restoring a tooth with a questionable prognosis may be the most acceptable course of action (Fig 3). However, that tooth should not be included as an abutment in a long-span fixed partial denture (FPD). Several

Table 3.—Contraindications and Increased Risk for Implant Failures Disease

Medical contraindications

Acute infectious diseases Cancer chemotherapy Systemic bisphosphonate medication (R2 year) Renal osteodystrophia Severe psychosis

Depression Pregnancy Unfinished cranial growth with incomplete tooth eruption

Intraoral contraindications Increased risk for implant failure or complications

Pathologic findings at the oral soft and/or hard tissues History of (aggressive) periodontitis Heavy smoking R10 pack-years (particularly in combination with HRT/oestrogen), alcohol and drug abuse Insufficient oral hygiene Uncontrolled parafunctions Post head and neck radiation therapy

Osteoporosis

Uncontrolled diabetes Status post chemotherapy, immunosuppressants or steroid long-term medication, uncontrolled HIV infection

Assessment

Absolute, but temporarily; wait for recovery Absolute, but temporarily; reduced immune status Risk of bisphosphonate-induced osteonecrosis (BON) Increased risk for infection, reduced bone density Absolute; risk of regarding the implant as foreign body and requesting removal despite of successful osseointegration Relative Absolute, but temporarily; to avoid additional stress and radiation exposure Relative, but temporarily; to avoid any harm to the growth plates, to avoid inadequate implant position in relation to the residual dentition; utilize hand-wrist radiograph to evaluate end of skeletal growth; single tooth implants in the anterior region not before 25th year of age Temporarily; increased risk for infection, wait until healing is completed Relative, requires supportive periodontal care; increased risk to develop peri-implantitis Relative or absolute, indicates cessation protocol; wound healing problems, locally reduced vascularization, impaired immunity, reduced bone turn over Absolute; wound healing problems, infection Relative; increased risk for technical complications Absolute, but temporarily; reduced bone remodelling, risk of osteoradionecrosis, implant placement 6–8 weeks before or R1 year after radiotherapy Relative; reduced bone-to-implant contact; consider calcium substitution, prolong healing period and avoid high torque levels for abutment screw fixation Relative, requires medical treatment; wound healing problems (impaired immunity, microvascular diseases) Absolute, but temporarily; wound healing problems, medical advice required (consider corticosteroid cover)

(Courtesy of Zitzmann NU, Krastl G, Hecker H, et al: Endodontics or implants? A review of decisive criteria and guideliness for single tooth restorations and full arch reconstructions. Int Endod J 42:757-774, 2009.)

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irreversible pulpitis or periapical periodontitis,

star ting point

RCT required (non-surgical)

assessment of tooth prognosis

- perio: periodontal health, sufficient residual attachment ? - endo: RCT feasible, root canals accessible ? - reconstructive: sufficient residual tooth substance ? (crown lengthening or or thodontic extrusion possibly required), adequate restoration feasible to avoid bacterial leakage

outcome of non-surgical RCT

diagnosis

treatment option

+

intracanal infection

non-surgical retreatment

outcome

+

-

-

isolated periapical infection

root canal not accessible

surgical treatment (periapical resection and retrograde obturation)

+

periradicular surger y (hemi-,, tooth-sectioning)

-

+

tooth untreatable

tooth extraction

-

fur ther treatment no replacement, implant treatment, prosthetic restoration

Fig 2.—Treatment considerations for root canal treated (RCT) teeth. (Courtesy of Zitzmann NU, Krastl G, Hecker H, et al: Endodontics or implants? A review of decisive criteria and guidelines for single tooth restorations and full arch reconstructions. Int Endod J 42:757-774, 2009.)

risk factors, particularly posterior location and lack of esthetic imperative may indicate that the tooth should be extracted and replaced with an implant. The placement of implants can expand the treatment planning options, adding short-span reconstructions or single units that are less likely to fail. Neighboring compromised teeth

pre-/treatment

periodontal

may be retained, if a single tooth is sacrificed and replaced with an implant. In full-mouth rehabilitation cases, the prognosis for a single tooth and treatment recommendations specific to that location may be outweighed by considerations in the

anterior

single-rooted

multi-rooted, furcation involvement, length of root trunk

simpler anatomy

difficult curves, accessory canals

marked undulation, aesthetics significant

small undulation, aesthetics marginal

(root morphology, accessibility)

endodontics

posterior

(root canal anatomy)

restorative/ reconstructive aesthetics (gingival undulation, papilla preservation, contralateral symmetry)

tooth preservation

implant placement1 1sufficient

bone volume provided

Fig 3.—Local factors influencing the predictability of treatment outcomes. (Courtesy of Zitzmann NU, Krastl G, Hecker H, et al: Endodontics or implants? A review of decisive criteria and guidelines for single tooth restorations and full arch reconstructions. Int Endod J 42:757-774, 2009.)

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extraction t ti off a single i l RCT tooth t th no treatment implant-supported single crown (ISC)

implant treatment not feasible and involvement of adjacent teeth required suitable as abutment fixed dental prosthesis (FDP) prognosis of adjacent teeth?

not suitable as abutment in a reconstruction maintain as single unit extraction

extraction of an RCT tooth in a full-arch rehabilitation sufficient periodontal support available fixed dental prosthesis (FDP)

additional implant support required implant-FDP potential implant positions?

resulting in which type of restorations (extent of tooth- or implant-supported FDP)? strategic/ elective extraction of maintainable teeth with questionable prognosis ?

prognosis of a single tooth versus treatment-related prognosis of the entire restoration tooth with poor prognosis, extraction indicated tooth with questionable prognosis, maintainable tooth with good prognosis, pretreatment indicated

Fig 4.—Reconstructive aspects in treatment planning. (Courtesy of Zitzmann NU, Krastl G, Hecker H, et al: Endodontics or implants? A review of decisive criteria and guidelines for single tooth restorations and full arch reconstructions. Int Endod J 42:757-774, 2009.)

overall treatment plan (Fig 4). Strategic extraction may be required to allow reconstructions that carry a better longterm prognosis. If possible, tooth extraction should be avoided for patients who have lost an implant previously, and young patients whose final tooth position is not determined and whose susceptibility to periodontal or peri-implant disease is unknown. Discussion.—The reported success rates for RCT and implant therapy are comparable, but may be misleading because of irregularities in defining success and survival in the literature. Appropriate guidance in choosing a course of treatment must consider not just success but also sitespecific and more general patient-related factors. Once these have been systematically evaluated, a treatment recommendation can be formulated.

Clinical Significance.—Many factors contribute to the decision to treat or extract a tooth or teeth. This review lays out the pros and cons of each situation and offers an excellent analysis of the factors influencing the decision-making process.

Zitzmann NU, Krastl G, Hecker H, et al: Endodontics or implants? A review of decisive criteria and guidelines for single tooth restorations and full arch reconstructions. Int Endod J 42:757-774, 2009 Reprints available from NU Zitzmann, Clinic for Periodontology, Endodontology and Cariology, Univ of Basel, Hebelstrasse 3, CH-4056 Basel, Switzerland; fax: þ41 61 267 2659; e-mail: [email protected]

Geriatric Dentistry Treating older patients Background.—Older patients often suffer a wide range of medical conditions and exhibit the consequences of previous illnesses (Table 1). It is important to understand the older patient’s medical history when evaluating or managing new health situations. Certain features distinguish illnesses in older patients (Table 2). For example, older

patients tend to have atypical or nonspecific symptoms, so thorough investigation of their complaints is essential. Ageing and illness adversely affect functioning (Table 3), which will alter the delivery of dental care in many cases. Clinicians must judge whether the patient will require special considerations, such as assistance in toileting or

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