A reliable method of pulp capping is a great benefit to patients, not only to manage short term postoperative pain, but also to mitigate sequelae and avoid the cost and morbidity of endodontic treatment. It also can be great practice-builder
WHAT IS SUCCESS?
In the literature, successful pulp cap is usually defined over a longer term, usually 5 or more years, and is usually evaluated as continued vitality, and freedom from clinical or radiographic symptoms and disease. Studies of this type are
1.FUKS AB PEDIATR DENT 1982,4: 240-244 81% SUCCESS ON PERMANENT INCISORS
2.BARTHEL CR J ENDOD 2000; 26: 525-528 37% SUCCESS@ 5 YEARS, 13% @10 YEARS
3.BOGAN G ET AL JADA 2008:39 (3) 305-315 97%SUCCESS @ 5 YEARS,
4.MENTE ET AL J ENDO 2010: 806-814 80%SUCCESS @ 5 YEARS,
Of course, immediate success is obvious – the patient experiences no discomfort postoperatively.
CONDITIONS FOR HEALING OF THE PULP
- A healthy and suitable patient
- A recoverable pulp
- Complete Caries Removal
- Histological repair
- Hermetic seal
- Inflammation management
1.A HEALTHY AND SUITABLE PATIENT
Patient’s attitude The extremely timid, hostile, untrusting, or litigious patient is not a good candidate for pulp capping, because of the possibility of post-operative pain. We need the patient on side.
Assessment of the patient’s health We are looking for indications that the patient has sufficient systemic vitality and recuperative powers to recover from the insult. The presence of multiple non-vital teeth is cautionary, indicating general pulpal fragility, a factor is some patients. Smoking tobacco reduces success because of peripheral capillary constriction. General ill-health, chemotherapy, poor nutrition all are cautionary.
2.A RECOVERABLE PULP
Symptoms For success, inflammation must not have extended to the apex; the pulp may be hyperemic but not to the point of pain persisting after hot/cold stimulus. Tenderness to vertical percussion also contraindicates successful pulp cap.
Radiograph The x-ray must show no condensing osteitis. Also, a threadlike canal limits success because we need a patent canal with sufficient circulation to recover from the insult.
Upon exposure Once exposure occurs, ask these questions to refine the prognosis.
- Are we able to get the contiguous dentin 99% debrided of decay?
- Was there any frank introduction or debris into the pulp chamber, and, if so, –did it bleed out?
- Is there no bleeding despite an exposure? If so, it may indicate a fibrosed and degenerative pulp.
- How big was the exposure? Can the resulting wound heal without occluding some portion of the pulp through secondary dentin deposition? This is applicable when thinking of capping a class V exposure. The literature reports that an exposure of up to 2mm is cappable.
- Pulp behavior – does it clot in less than 5 minutes? Is there serous exudate after the clot?
- Is the clot stable after disinfection?
These parameters combine to inform clinical judgment of the health and reparative potential of the pulp.
3. COMPLETE CARIES REMOVAL; LEAVING RESIDUAL CARIES?
Leaving residual caries has been popularized in recent years, with some longitudinal studies to corroborate the approach. “LONG-TERM SURVIVAL OF INDIRECT PULP TREATMENT PERFORMED IN PRIMARY AND PERMANENT TEETH WITH CLINICALLY DIAGNOSED DEEP CARIOUS LESIONS”
RENE´ GRUYTHUYSEN, DDS, PHD, GUUS VAN STRIJP, DDS, PHD, AND MIN-KAI WU, MSD, PHDE
JOE — VOLUME 36, NUMBER 9, SEPTEMBER 2010
The author rejects this approach as less definitive than doing one’s best to ensure complete caries removal. As soon as it is “ok” to leave some caries, the door is open to subjective laxity.
- At the very least, residual caries are non-retentive, robbing the restoration of needed surface bonding area.
- Also, caries is non-structural, and is incapable of carrying structural loads, producing a weaker restoration.
- Finally, this study was performed on pedodontic patients, not adults. Extrapolating the process to adults is bad science.
The certainty of bacterial kill is increased if meticulous care is taken to reduce the bioburden to an absolute minimum, walking the fine line of maximum removal versus potential damage to the host. As in all areas of life, there is nothing that cannot be done cheaper and with lesser quality. If we do not aim high we do not score high.
4. DISINFECTION PRODUCTS: Optim 33TB and Q-Mix
Many agents have been proposed for prep disinfection; sodium hypochlorite, chlorhexedine, gluteraldehyde, and other agents in various concentrations and for various durations. This writer’s current recommendation is Optim 33 TB (SciCan), a hard surface disinfectant based on “accelerated peroxide”. This product is faster and less cytotoxic than NaOCl, producing a microbial kill of 10 log-6 in one minute, and is a more effective disinfectant, having been certified by Clinician’s Report and other agencies as producing the necessary TB and Polio virus kill. Compared to chlorhexedine, the effective spectrum of disinfection of Optim 33TB is wider. Being in EPA category 4, no precautionary statements are warranted. A review can be found by Omidbakhsh ete alin the AJ of Infect Cont June 2006.
Relative to many disinfectants, such as hypochlorite and gluteraldehyde,there is no skull and crossbones on the labelling. That should say something.. Optim 33TB is less cytotoxic than gluteraldhyde, and both quicker and less cytotoxic than sodium hypochlorite (one minute kill versus 3.5 minutes). It is faster by one minute than chlorhexedine 2% and gluteraldehyde in the form of Gluma 3, G-Force, or Danville Microprime G.It is a clear and odorless and colorless solution is available from most dental supply houses.
The other agent recommended is Q-Mix?, by Dentsply/Tulsa In endodontic treatment it opens tubules by removing the smear layer, hence the name. The active ingredient for this is 15% EDTA.It also contains CHX 2% and a surfactant.
DISINFECTION PROTOCOL IN PROBABLE EXPOSURE/ CARIES REMOVAL SCENARIO
This method for complete caries removal requires the use of Caries Detector. See Caries Detector It is wise to remove caries completely at the perimeter of the preparation first, establishing a clean cavosurface, especially the gingival margin and in the mantle dentin at the DEJ. Once perimeter margins are established, progressively approach deeper areas, re-disclosing and removing until the dentin is hard and no more than lightly pink with stain.Experience will indicate a probable exposure when soft dentin persists as one approaches the usual location of the pulp.
Before that moment of likely exposure, disinfect with Optim 33TB (SciCan)for one minute, renewing the solution at the 30-second mark to sanitize the operative field and minimize gross innoculation of the pulp.
Finish excavation with hand instruments or very slowly rotating slow speed burs and a light touch. Ensure that the patient is comfortable and not likely to make any sudden movements.
If an exposure does occur in the final moments of excavation, it will be as clean and innocuous as feasible, having reduced the bioburden prior to the exposure. This approach elevates the prognosis.
Once excavation is complete, treat the dentin for one minute with Q-Mix (Dentsply/Tulsa). It contains chlorhexedine, EDTA, and a surfactant. EDTA removes the smear layer created during cavity preparation, opening dentinal tubules to allow deeper penetration of Optim 33TB. Wash Q-Mix away with distilled water in a Monoject 212 syringe under low pressure, not a triple syringe. Apply Optim 33TB again for a minute to disinfect the now open dentinal tubules and pulp exposure if present.
5. RESTORING BONDABILITY
The exposure of the dentin to a strong oxidizing agent reduces bond strength with DBAs. See Erdemir et al JOE, 2004 and Nikaido et al, AM J DENT 1999. Hence the dentin surface needs to be exposed to a reducing agent to restore bondability by neutralizing oxidation effects. SmearClear (SybronEndo), also contains a reducing agent, 15% EDTA.
EDTA has been shown to restore bondability by Doyle et al, JOE, 2006. After being applied for one minute, bonding proceeds as normal. The necessity of postponing bonding for three weeks, as is practiced following tooth bleaching procedures, is thereby averted, and treatment can be completed at one visit.
The other ingredient of Q-Mix is chlorhexedine, which has been shown to have no effect on bond strength by Santos et al, JOE, 2006. and Perdiao et al, AM J DENT 1994, and it also confers another step in disinfection of the preparation to aid healing of the pulp cap.
Thus the sequence of irrigation in pulp cap is as follows:
- Optim 33TB for one minute prior to exposure. Complete excavation.
- Q-mix for one minute to remove smear layer and open tubules
- Optim 33B for one minute to penetrate tubules
- Q-Mix for one minute to regain bondability
6. HISTOLOGICAL REPAIR
The aim of a pulp capping material is promote reparative dentin and to induce histological repair of the pulp. Classically, calcium hydroxide paste formulations, such as “Dycal” or “Life”, in their self-cure formulation have a long history of use, yet research identifies two drawbacks;
- immediate post-operative inflammation
- calcigenesis that is porous, irregular,incomplete, with histologically evident tunnel defects.
Mineral Tri-oxide aggregate, (MTA) is more effective on both counts. Pulpal response to this agent has been universally outstanding in all research, in both adult and pedodontic applications. Vitality is maintained over the long term.
MTA MECHANISM OF ACTION; INTRACELLULAR EVENTS
Why is MTA so effective and successful? An article to explain the repair mechanism at the cellular level has been written by Perinpanayagam “Cellular response to Mineral Trioxide Aggregate Root end Filling materials”, JCDA June 2009 Vol 75, No.5 369-372 and can be found at http://www.cda-adc.ca/jcda/vol-75/issue-5/369.pd
To confirm this, Google on MTA and follow the trail. You will find hundreds more references.
ARE RESIN/SILICATE PRODUCTS EQUIVALENT TO MTA?
The search for a better calcigenic material follows on the histological research of pioneer Dr. Werner Geurtsen. His studies on immortal human cell cultures reveal that direct pulpal contact with many resin products impairs pulp metabolism. Also, resin products do not produce calcific repair.
In his studies, numbers of composite resins were assayed in vivo in immortal human cell cultures, and found to produce effects consistent with apoptosis, the progressive loss of cell respiratory capacity. As well, little or no calcific repair was found after resin pulp caps.
It was found rather gravely that mutagenic change was demonstrated with some resin products, and other deleterious changes such as apoptosis and decline in intracellular glutathione, indicating impaired cell respiration. See Pulp protection and biocompatibility for articles authored by Dr. Geurtsen.
It is critical, therefore,that the profession explore this research area with more zeal, if we wish to arrive at a truly evidence-based methodology.
PULPECTOMY AS AN AID TO PULP CAP
Should pulp be removed other than what has occurred operatively? If the pulp tissue stands proud of the hard tissue, excise it with a new, clean high-speed bur, cutting wet. This reduces the volume and surface area requiring histological repair. If one is skilled with a diode laser, that could be used to ensure a minimally traumatic and non-bleeding excision.This author has no experience with this method, and notes that correct access with a laser tip may not be possible.
If the pulp does not coagulate within two minutes, there can be several possible interpretations. Research Mente et al J ENDO 2010: 806-814,suggests that a coagulation time of greater than 5 minutes is a contraindication for pulp cap.
The underlying cause for prolonged bleeding may not be irreversible pulpitis, but rather, systemic i.e. an easy-bleeder type of patient, rather than a diseased pulp. High consumption of sugars, alcohol, vitamin C or red wine may be contributory. High anxiety may also contribute. Such a case still may have a good prognosis.
Try placing aluminum chloride with a microbrush on the exposure for several seconds,followed by a wash of Q-mix for several seconds. In other words, this is a same technique as is used to control bleeding gingival tissues, See Hemostatic Etch for more information. The Q-mix duration is only several seconds and it follows the astringent rather than preceding it. This method leaves no chalky residue, unlike when aluminum chloride is used alone. This lightly etched dentin will be coated with either MTA or GI cement subsequently. If the etch does extend past the zone of pulp cap and liner, it is of no significance clinically, as etch times of up to one minute have been shown to have little effect on final bond strength. See Reality Yearbook 2012, page 525.
The critical measure is to avoid placing a restoration over a large clot. We want a very small or non-existant clot, to keep the wound accessible to the bloodstream, not a clandestine reservoir inviting bacterial colonization. The literature reports an exposure less than 2mm is pulp-cappable.(Mente et al)
There is a need in MTA pulp cap to develop a concise chairside protocol for its implementation. For years Tulsa Dental held the sole patent for MTA in America, and they chose to price this product very high, and this has restricted its use. As well, Tulsa MTA requires 24 hours to set, so that a temporary restoration was needed to allow sufficient set time. This is counterproductive, economically inefficient and also lowers success rates. See Mente et al J ENDO 2010: 806-814).
Angelus White MTA
But new horizons have opened up, (January 2011). A new, more effective MTA is now available. The product, Angelus White MTA, is available from CRD (Clinical Research Dental, London Ontario, 1800 265 3444,) at very low cost. Angelus MTA has a 15 minute set time. It requires moisture to set; on the pulp side, that moisture is provided by the pulp itself. On the restoration side, that will be provided by glass ionomer cement.
CRD markets an MTA placement instrument,a “Dovgan” placement instrument,which resembles a very small amalgam carrier with a long, anteater-like curved tip. This carrier is designed for root perforation repair and apical retrofill, and there are three tip sizes. This Handbook recommends the middle size, 0.99 mm.which allows easy placement of this material.
7. COVERING THE MTA PULP CAP
After a pellet of MTA is placed onto or just beside the exposure, where it seems to miraculously cling, it is spread to fully cover the desired area with a PICH, or the small end of a ball burnisher using a supremely delicate touch. If it is too dry to respond to touch, dampen a microbrush with distilled water,blow it off, and touch the MTA into place with this lightly damp brush. The added moisture will soften it enough to allow it to spread. This is the only technique-sensitive aspect of this procedure. Too much moisture and the MTA dissolves.
Practice this outside of the mouth to find the skill to gently tease it to place with a damp Microbrush tip. At the present time it is recommended that the MTA pulp cap be covered with a faster-setting material as soon as it is placed, so that the restoration may proceed through the normal etch/prime/bond sequence in a timely fashion. A second goal is to use a visibly contrasting material so that subsequent re-exposure is not likely if the tooth is ever re-treated. What is the best material for covering the MTA pulp cap?
Polycarboxylate is histologically very compatible with the pulp, but its sticky quality makes it difficult to manipulate. Luting Glass ionomer, such as Ketac-Cem?, (3M Espe) is very biocompatible, according to other research by Geursten et al, see Pulp protection and biocompatibility
What about the resin modified products being presently offered for pulp cap in the marketplace? Examples are Theracal, Limelight, Calcimol-LC, Biocap, etc. Initial research has shown that apotosis, i.e., decreased sell respiration rate, is induced by at least several of these new products. Also,at least one of these products is tooth-colored, and it seems clinically unwise to use a product that does not warn subsequent operators that one is approaching a previous pulpal event.
Once the MTA is placed, this Handbook recommends it be covered with powder/liquid glass ionomer luting cement, such as Ketac-cem or Fuji-cem. An effective instrument is a Dycal placement instrument, or the Hufriedy PICH instrument (which forms part of the Bandbender kit). Flow the glass ionomer over the MTA and beyond the exposure perimeter by at least one millimeter to establish a perimeter dentin/ionomer bond that will resist dislodgement under polymerization contraction forces. Besides overlaying the MTA in location,isolating it from the resin restorative steps, the bright white hue informs any future operator of the proximity of an old wound, and the need for caution.
An expedient alternative may be conventional resin-free calcium hydroxide, such as “Life” or “Dycal”. These paste-paste calcium hydroxide formulations are quick-setting and indicated for expedience rather than as a pulp cap,because they are overly caustic and imperfectly calcigenic.Clinical judgement informs how thick the dentin should be before resorting to Dycal. The speed of set can even make it difficult to get the material to place before hardening develops. GI as above is the more forgiving product
Is there any concern about the biocompatiblity of powder/liquid GI cements? No. Guersten found no adverse histological response to classic GIs in his research. See Pulp protection and biocompatibility
CLINICAL TIP; MAINTAINING THE DOVGAN CARRIER
Note that the Dovgan carrier must be immediately cleaned of residual MTA after use. Once MTA sets, it is hard and tenacious. Liquid 37% phosphoric acid is very effective for cleaning because its acidity combines with the MTA, Ph 13, in a classic acid/base reaction. This immediately dissolves the MTA into a soluble, easily removed material. If MTA does inadvertently set in the carrier, the apical portion of the carrier tube can be cut off rather than be discarded. Otherwise,if it does harden in place, replacement of the tip will be required.
A new product, Biodentine, has been recently introduced by Septodont. It is designed to be triturated in an amalgamator and placed as a temporary filling for the entire cavity, which must be replaced with a permanent restoration in a subsequent visit. More information can be found at http://www.septodont.ca/search/node/biodentine.
This second visit is less expedient than the above MTA protocol,and requires greater expense to the patient. It is also predictive of lower success. The pulp cap literature reports better success in single-intervention rather than multiple-intervention treatment, see Mente et al,J. Endo May 2010.
The setting time for Biodentine is close to ten minutes and several independent assessors, viz. The Dental Advisor and Reality Research, have found it inordinately sticky. Precise placement and manipulation on an exposed pulp might be difficult if not impossible, and the overall set time would be longer than with the MTA/GI protocol, which requires about five minutes of set time.
Theracal LC (Bisco)
Theracal LC by Bisco has been introduced recently to the market with considerable marketing finesse. However, being light-cured one immediately suspects resin components may lack pulpal compatibility. A study by Hebling et al in Am J Dent, June 2009, “Cytotoxicity of Resin-based light cured liners”, showed a 35% reduction in cellular metabolism in 24 hours, and 46% after 7 days. This is the classic picture of apotosis. The authors also concluded that this LC resin-based MTA is solubilized over time.
8. MTA SEAL
MTA is completely insoluble once set. A well-bonded composite resin restoration achieves no leakage in the short term when well-placed. Reliable, long-term, insoluble adhesion in the biotic battlefield of the oral cavity is required for pulpal healing. Neither amalgam nor zinc-oxide eughenol temporary cements are demonstrably free of microleakage, yet clinical success in the annals of dentistry can be found. This illustrates that clinically we rely first and foremost upon the robust healing powers of the patient for success. However, the research of Mente et alshows higher clinical success if the final restoration is placed on the same day as the pulp cap, and this has driven the development of the technique outlined above.
9. PRE-EMPTIVE INFLAMMATION AND PAIN MANAGEMENT
Any exposed and medicated pulp is going to go through a period of postoperative inflammation. Over the years NSAIDS for 24 hours have produce a smooth painless transition on the road to pulpal healing, as compared to doing the same journey without NSAIDs. Ibuprofen 400mg x6 is prescribed, taken regardless of symptoms. It has been suggested by researchers that this helps to prevent pulpal self-strangulation in the critical first day after pulp cap.
Even patients on blood thinners are considered for this treatment, in that the mechanism of Ibprofen is not synergistic with aspirin therapy if the Ibuprofen follows the aspirin by 1 to 2 hours.According to Becker,D., in an article titled “Antithrombotic Drugs: Pharmacology and Implications for Dental Practice”, Oral Health Feb 2014, Vol 104, No 2, pg 20-30, “the antiplatelet influence of aspirin occurs within one hour of administration, and one solution might be to instruct patients to take their daily aspirin upon rising and delay the first does of NSAID for 1-2 hours”.”By this time the anti-platelet influence of aspirin will have been established”.
It should be appreciated that the loss of a night’s sleep to dental pain is a potent medical hazard. The only patients who do not receive a pre-emptive anti-inflammatory schedule are those on long-term anti-inflammatory therapy, such as Celebrex. Naproxen could also be considered, at 250 to 500mg q12 hours.
It is also possible to consider the use of Dexamethasone 5 to 10mg, stat, and q6h to q12h for 36 hours. The dosing regimen for dexamethasone is extremely variable, so experience may guide individual practitioners to choose another dosage regimen.
Many patients are non-compliant with prescriptions, so devote some time and emphasis to impress the patient with possible consequences if they are non-compliant; i.e. there could be hell to pay, in fact, the whole treatment could fail in an agony of pulpal death. That usually gets their attention.
Patient attitude control
Get the patient on side: be sure they know the odds and that we are dealing with a biological system. I say things like: “This material is the best for your situation according to hundreds of international studies….” “From my experience it is likely within the powers of this tooth to recover…” “Our goal with this step is to keep your tooth alive and to save you the cost of $780 for a root canal and three appointments in the chair…, plus another thousand dollars for a crown that will be needed to protect a tooth that is weakened by root canal treatment..” “Commonly, there is no pain and the tooth heals perfectly without long term consequences…” “We have to be aware, however, that sometimes this exposure will be the last blow to a shaky pulp, so we can’t be entirely sure of success…”
- Safety net –let them know quite precisely how they can contact you if there is pain; furnish them with written numbers.
- Follow-up call in 24 hours.Almost always this is a rewarding affirmation, and a good practice builder.Patients are impressed when their dentist calls them to check in.
FUTURE ANTI-INFLAMMATORY MODALITIES
The use of low-level laser therapy in the form of photobiomodulation to reduce pulpal inflammation shows promise. Studies have shown reduced cytokinins, increased respiration in mitochonria, and other beneficial tissue responses in periodontal and bone healing applications, notably immediate post operative peri-implant inflammation. Shorter healing times and increased early stability in implants are the result. This may be brought into pulp cap management in the future. Right now there are few standard protocols despite many techniques in clinical use. See Clinician’s Report Jan 2010 for a survey of clinical respondents.
The time taken to accomplish these steps is from ten to fifteen minutes. The products used are not expensive nor stand-alone single-use materials, nor do they have a rapid expiration date. Post-operative advice and Ibuprofen are not costly inputs. Therefore this writer adds a fee to the basic fee for the restoration commensurate to this time outlay.
This writer believes there is no point to recommending a procedure to practitioners than cannot be accomplished within the normal fee-for-service structure of general private practice; if monetarily impractical, any new approach will just not be used. Hopefully, with some thought and organization, practitioners reading this page will be able to implement this treatment. It is empirically sound, better than anything else in common use for pulp capping, and it has been clinically excellent for a number of years. at the moment 95% effectiveness at immediate comfort, and an 85% continued vitality and radiographic normality after five years.