Dr. Sigurdsson - New Developments in Endodontics PDF

New Developments in Endodontics: Vital Pulp Therapy and Regeneration Asgeir Sigurdsson, cand. odont. M.S. Professor and Chairman Department of Endodontics [email protected] Immature Non-Vital Tooth Challenges R. C. filling of open apex R.C. infection Thin weak root wall Immature Non-Vital Tooth...

New Developments in Endodontics: Vital Pulp Therapy and Regeneration Asgeir Sigurdsson, cand. odont. M.S. Professor and Chairman Department of Endodontics [email protected] Immature Non-Vital Tooth Challenges R. C. filling of open apex R.C. infection Thin weak root wall Immature Non-Vital Tooth Revascularization Pulpal Necrosis Pulp revascularization is favored when the apical foramen is not completely formed. (Öhman, 1965; Skoglund and Tronstad, 1981; Kristerson and Andreasen, 1984; Kling et al., 1986; Cvek et al., 1990a). Pulpal Necrosis The occurrence of pulp revascularization is enhanced if the apical foramen is more than 1.1 mm wide in humans. (Kiling et al. 1986). Pulpal Necrosis AND pulp revascularization is highly dependent on the presence or absence of bacteria in the pulpal lumen. (Cvek et al. 1990 and 1990) Pulpal Necrosis Complete revascularization of the pulp in a tooth with an open apex after avulsion could be expected to be between 18 and 25% - more likely the larger the apical opening is. (Cvek et al. 1990 and 1990) For luxation injury it is likely to be much higher! Traumatic Injuries Possible complications: üPulpal obliteration "Of 122 teeth showing partial or total pulpal obliteration, 16 (13%) teeth showed periapical signs of pulpal necrosis" (Jacobsen & Kerekes 1977) Root Fracture Another type of revascularization Root Fracture Definition Fracture involving dentin, cementum and pulp Root Fracture Treatment - reduce the displaced segment - immobilize (?) - follow-up critical Root Fracture -Treatment principles: -Do not attempt to move the tooth unless it is very loose. X Root fracture - Extrusion Luxation Root fracture - Extrusion Luxation FORCE Root fracture - Extrusion Luxation FORCE Root fracture - Extrusion Luxation FORCE Root fracture - Extrusion Luxation FORCE Root fracture - Extrusion Luxation Root Fracture Prognosis: Permanent pulp necrosis was found only in 20%, 70% of those successfully treated endodontically and almost all of them only in coronal segment. (Zachrisson and Jacobsen 1975) Necrotic Pulp When the pulp in an immature tooth becomes necrotic and the pulpal space infected the success of any endodontic treatment is severely reduced. - Difficult to treat - Inadequate strength Necrotic Pulp “Until now it has not been an option to wait for possible revascularization because once bacteria is in the pulpal space there is no possibility of re-growth of tissue.” And it has been believed the pulp progenitor cells necessary for the proliferation of pulpal tissue can not survive the infection. (Cvek et al 1990, Iwaya et al 2001) Sato et al. 1996 Studied the potential of a mixture of: ciprofloxacin, metronidazole minocycline Is the mixture able to penetrate through root dentin? And can the mixture kill cultured bacteria in deep layers of extracted tooth root dentine? Sato et al. 1996 Confirmed that in extracted teeth there was penetration of the antibiotic paste through dentine. And the mix had the antibacterial efficacy expected against bacteria infecting the dentine. Application of Tissue Engineering Concepts to Regenerative Endodontics It has been shown that the evoked-bleeding step in pulpal regeneration triggers the significant accumulation of undifferentiated stem cells into the canal space These cells might contribute to the regeneration of pulpal tissues seen after antibiotic paste therapy of the immature tooth with pulpal necrosis. (Lovelace TW et al., 2011) (Lin L et al. 2021) (Lin L et al. 2021) Any Immature Tooth The main objective of maintaining an immature tooth in a growing child after severe injury and/or pulpal necrosis is to: Allow continuation of alveolar growth and maturation Beware!!!!! The three mix will severely stain the tooth crown if placed too close to the crown Beware Therefore many have now suggested to only use mixture of: Ciprofloxacin and metronidazole Or Calcium Hydroxide paste Recent studies have indicated that the antibiotic mixture has higher success rate that Ca(OH)2 Vital Pulp Therapy Requirements for success in direct pulp capping 1. Pulpal Status Healthy pulp (trauma/iatrogenic) - success > 90% Inflamed pulp (caries) - success < 35% (Al-Hiyasat AS et al, JADA 2006) So What Do We Know? Role of Bacteria in Apical Periodontitis: Classic study Kakahashi S, Stanley HR and Fitzgerald RJ. Oral Surgery Oral Medicine Oral Pathology 20:340; 1965 “The effects of surgical exposures of dental pulp in germfree and conventional laboratory rats.” Hreinsun á vef Hreinlæti! So What Do We Know? We have discussed already few weeks ago that ü Pulp Capping is in selected cases very predictable! Complicated Crown Fracture In case of a pulp capping after traumatic exposure, where the remaining pulp was relatively healthy and a bacterial tight seal was achieved one can expect: up to or over 90% survival of the pulp Long Term Clinical Assessment of Direct Pulp Capping “Direct capping with calcium hydroxide should not be used on pulp which has been exposed as a result of penetrating caries.” Clinical studies 2338 cases: ü “The risk of failure was increased if the pulp was diseased before capping.” (Baume and Holtz 1981) Long Term Clinical Assessment of Direct Pulp Capping However, teeth with incomplete root formation in young individuals that present to the clinic with mild or no symptoms it might be justified. Beware thought that no symptoms does not equate to vital health pulp! However!!! There seems to be high risk of calcification with all pulp capping and especially long term pulpotomies: - Deep into the roots - Irrespective of the age of the patient - Root canal treatment, if needed at later time, can be quite difficult Treatment of deep caries lesions in adults: randomized clinical trials A randomized clinical multicenter trial n=343 analyzed teeth Patients with minimal or no presenting symptoms Compared stepwise vs. direct complete excavation, and direct pulp capping vs. partial pulpotomy of well-defined deep caries lesions. In conclusion, stepwise excavation decreases the risk of pulp exposure compared with direct complete excavation. Does not guarantee pulpal vitality however! (Bjørndal L et al. 2010) Treatment of deep caries lesions in adults: randomized clinical trials A randomized clinical multicenter trial n=343 analyzed teeth (one year follow-up) The stepwise excavation group success = 74.1% The complete excavation group success = 62.4% Teeth with unexposed pulps 89.9% Pooled pulp survival rate of exposed pulps = 33.2% after 1.5 years (Bjørndal L et al. 2010) Treatment of deep caries lesions in adults: randomized clinical trials So what is the trick? Exclusion criteria were: - prolonged unbearable pain - and/or pain disturbing night sleep; - no response to cold and electrical pulp testing; - attachment loss > 5 mm; - apical radiolucency (Bjørndal L et al. 2010) Stepwise Excavation Procedure A closed lesion before and after first excavation (Bjørndal L. 2008) Stepwise Excavation Procedure A calcium hydroxide – containing base material and provisional restoration (Bjørndal L. 2008) Stepwise Excavation Procedure After final excavation, new layer of calcium hydroxide – containing base and final restoration (Bjørndal L. 2008) And now 5 years later n=58 The stepwise success was 60.2% compared with the nonselective carious removal 46.3% (P = 0.031) After pulp exposure, only 9% of the analyzed patients were assessed as successful. Indicating that the prognosis is highly dubious following conventional pulp-capping procedures (direct pulp capping or partial pulpotomy) in deep carious lesions in adults. (Bjorndal et al. 2017) Key Factors In case of direct pulp capping in case of caries exposure: - Patient has to be asymptomatic; no spontaneous pain or provoked pain prior to treatment. - Normal (near normal) responses to vitality tests. - Age of the patient is secondary to symptoms. - Though younger the better. - Size of the lesion might matter, - Some argue in case of pinpoint exposure it should be made larger. Permanent Teeth (open/closed apex) AFTER Complete Caries Removal - Using Rubber Dam (Caries Detector Dye?) Pulp Exposure Preop Dx: reversible or Irreversible pulpitis No Yes Gently enlarge the pulpal wound – high speed diamond. Assess the Bleeding from the Pulp after 3-5 min (up to~ 10 min) NaOCl (3-5.25%) with cotton pellet Calcium Silicate Base Bonded Restoration Possible alternative Dycal Direct Pulp Cap Calcium Silicate Base or Ca(OH)2 Bonded Restoration Controlled Not Controlled Pulpotomy Assess the Bleeding from Canal Openings NaOCl wash again Controlled CS Cap or Ca(OH)2 - Bonded Restoration Not Controlled - Pulpectomy (Based in part on Dr. R. Lemon 2022) When Is the Pulp Condemned? Failures of pulp capping: - Early: Likely to related to misdiagnosis of the severity of the pulpitis disease and insufficient pulp tissue removal. - Late: Likely related to the quality and sealing ability of the restoration and the mineralized bridge - secondary infection