Walter R. Bowles

Challenges in regenerative endodontics: a case series.

INTRODUCTION An immature tooth with pulpal necrosis and apical periodontitis presents a unique challenge to the endodontist. Endodontic treatment options consist of apexification, apical barriers, or more recently, revascularization. The purpose of this case series is to report three cases that used revascularization protocol as described by Banchs and Trope. Each case presented its own special circumstances and challenges. The lessons learned from each case provided guidance for more predictable outcomes on subsequent cases. METHODS Six immature teeth with apical periodontitis (in three patients) were treated via the revascularization protocol using irrigants, a triple antibiotic paste, and a coronal seal of mineral trioxide aggregate and composite. RESULTS For follow-up, all six teeth showed resolution of periapical radiolucencies, whereas three of six teeth showed continued root development. Two teeth displayed a positive response to vitality testing. CONCLUSIONS Results from this case series show that revascularization is a technically challenging but effective treatment modality for the immature tooth with apical periodontitis. Based on this case series, the following recommendations are made to help with the revascularization technique: (1) clinicians should consider the use of an anesthetic without a vasoconstrictor when trying to induce bleeding, (2) a collagen matrix is useful for the controlled placement of MTA to a desired and optimal level, (3) patients/parents should be informed about the potential for staining, especially in anterior teeth when the paste contains minocycline, and (4) patient/parent compliance with the necessary multiple appointment treatment plan may be significant for case selection.

Pharmacology of peripheral neuropeptide and inflammatory mediator release

Research conducted in the last 10 years has increased our knowledge on pain mechanisms substantially. Although many local tissue mediators, including neuropeptides, are known to exert pro-inflammatory effects, comparatively little is known about the actual tissue levels of these inflammatory mediators and their pharmacologic regulation. This article describes two new methods, clinical microdialysis and superfusion of dental pulp, which provide data on the pharmacology of peripheral neuropeptide and inflammatory mediator release. Collectively, these methods provide a biochemically based approach toward determining the mechanisms and management of orofacial pain.

Cone-beam computed tomography evaluation of maxillary sinusitis

INTRODUCTION Dental pain originating from the maxillary sinuses can pose a diagnostic problem. Periapical lesion development eliciting inflammatory changes in the mucosal lining can cause the development of a sinusitis. The purpose of this study was to describe the radiographic characteristics of odontogenic maxillary sinusitis as seen on cone-beam computed tomography (CBCT) scans and to determine whether any tooth or any tooth root was more frequently associated with this disease. METHODS Eighty-two CBCT scans previously identified as showing maxillary sinus pathosis were examined for sinusitis of odontogenic origin in both maxillary sinuses. RESULTS One hundred thirty-five maxillary sinusitis instances with possible odontogenic origin were detected. Of these, 37 sinusitis occurrences were from nonodontogenic causes, whereas 98 instances were tooth associated with some change in the integrity of the maxillary sinus floor. The average amount of mucosal thickening among the sinusitis cases was 7.4 mm. Maxillary first and second molars were 11 times more likely to be involved than premolars, whereas either molar was equally likely to be involved. The root most frequently associated with odontogenic sinusitis is the palatal root of the first molar followed by the mesiobuccal root of the second molar. CONCLUSIONS Changes in the maxillary sinuses appear associated with periapical pathology in greater than 50% of the cases. Maxillary first or second molar teeth are most often involved, and individual or multiple roots may be implicated in the sinusitis. The use of CBCT scans can provide the identification of changes in the maxillary sinus and potential causes of the sinusitis.

Tissue Levels of Immunoreactive Substance P are Increased in Patients with Irreversible Pulpitis

Odontogenic pain often involves inflammation of dental pulp tissue. Dental pulp is highly innervated with a subpopulation of sensory neurons containing neuropeptides. Substance P, released from afferent fibers (e.g. nociceptors) is associated with the development of neurogenic inflammation. In this study, we tested the hypothesis that irreversible pulpitis is associated with increased activity of peptidergic neurons, as measured by increased pulpal levels of immunoreactive substance P (iSP). We determined in vivo pulpal levels of immunoreactive substance P in human teeth with a diagnosis of normal pulp or irreversible pulpitis using CMA/20 microdialysis probes inserted into vital pulps of 24 teeth from 21 patients. Probes were perfused with a modified Locke-Ringers buffer and immunoreactive substance P levels in the dialysate were measured using a radioimmunoassay. Mean extracellular levels of immunoreactive substance P were significantly higher (>8-fold) in teeth diagnosed with irreversible pulpitis than immunoreactive substance P levels in dental pulp diagnosed as normal (147.7 +/- 34.0 pM versus 18.2 +/- 6.2 pM). These observations suggest that biochemical measures of inflammatory mediators exhibit significant change during irreversible pulpitis and may contribute to clinical signs and symptoms.

Evaluation of the combination of flurbiprofen and tramadol for management of endodontic pain

Effective management of endodontic pain represents a continuing challenge. In this study, we evaluated the efficacy of flurbiprofen and a novel centrally acting analgesic, tramadol, alone and in combination, for reducing pain in endodontic emergency patients. Patients (n = 49) were administered a local anesthetic and underwent pulpectomy. They were then administered, on a double-blind basis, either: (i) placebo (one capsule to start and then every 6 h); (ii) flurbiprofen (100 mg loading dose and then 50 mg every 6 h); (iii) tramadol (100 mg loading dose and then 100 mg every 6 h); or (iv) the combination of flurbiprofen and tramadol (as above). Pulpectomy combined with placebo medication resulted in a 50% reduction in pain by 24 h (p < 0.01). Patients treated with flurbiprofen and tramadol reported less pain, compared with placebo treatment at 6 and 24 h (p < 0.01 for both). These results suggest that a nonsteroidal anti-inflammatory drug/opiate combination, together with endodontic therapy, may be useful in the management of endodontic pain.

Evaluation of Pretreatment Analgesia and Endodontic Treatment for Postoperative Endodontic Pain

This study compares single-dose ibuprofen pretreatment for postoperative endodontic pain. Thirty-nine emergent patients were randomly assigned to 3 groups: placebo, ibuprofen tablets, or ibuprofen liquigels. Patients recorded their pain levels before and at the end of treatment, then every 6 hours for 24 hours after administration of the medications and standard endodontic treatment. Pain evaluations by using 3 pain scales (visual analog scale [VAS], category, and Heft-Parker) were highly correlated, suggesting the rationale for only using one pain scale in pain studies. No significant differences in postoperative pain levels were found between either single-dose ibuprofen formulation or the placebo control group (P = .84). Patients treated with calcium hydroxide versus obturation did not differ in postoperative pain levels (P = .44). This study suggests that single-dose pretreatment analgesia alone in endodontic pain patients will not significantly reduce postoperative pain below the reduction in pain from endodontic treatment.

Gender Differences in Analgesia for Endodontic Pain

The purpose of this prospective clinical trial was to investigate the analgesic efficacy of three oral medication groups on postoperative endodontic pain in male and female dental patients, with an emphasis on analgesic differences between the sexes. Forty-three patients were administered ibuprofen 600 mg, placebo, or pentazocine 50 mg/0.5 mg naloxone in a randomized, double-blinded manner. Beginning immediately after endodontic treatment, patients took the assigned medication every 6 hours for 24 hours and recorded their degree of discomfort on a 100-mm visual analog scale. Statistical analysis of the data showed that ibuprofen 600 mg provided statistically significantly greater analgesia than placebo at 6 and 12 hours (P = 0.0014 and 0.0024), and pentazocine/naloxone provided statistically significantly greater analgesia than placebo at 12 hours (P = 0.0084). Sex-dependent differences were noted within the pentazocine/naloxone group, which showed significantly greater analgesia in females compared with males (P = 0.007).

Prostaglandin E2 Enhances Bradykinin-evoked iCGRP Release in Bovine Dental Pulp

Mediators produced during inflammation are responsible for hyperalgesia and expression of neurotransmitters and receptors in the nervous system. The production of bradykinin (BK) and the prostaglandins (PGs) may regulate initiation of pain. This study tested the hypothesis that BK and prostaglandin E2 (PGE2) have a positive interaction in evoking neurosecretion of immunoreactive calcitonin gene-related peptide (iCGRP). Bovine dental pulp was prepared and stimulated by the superfusion method with BK alone and in combination with PGE2. Kinin receptor antagonists to bradykinin-evoked release of iCGRP were also tested. Also tested was the hypothesis that dental pulp contains cither the B, or B2 or both BK receptors. Results showed that PGE2 enhanced BK-evoked iCGRP release by more than 50%. Western immunoblots revealed detectable B, receptor protein with no detectable B1 receptor protein. We conclude that BK evokes iCGRP release from bovine dental pulp which is enhanced by a positive interaction with PGE2. Neurosecretion is evoked from isolated terminals of dental pulp fibers via the bradykinin B2 receptor-dependent mechanism.

Frequency and distribution of radiolucent jaw lesions: A retrospective analysis of 9,723 cases

OBJECTIVES Practitioners should be aware of the occurrence rate and usual location of radiolucent jaw lesions. The aims of this study were to examine the frequency and location of radiolucent jaw lesions, including apical granulomas, apical cysts, keratocystic odontogenic tumors (KOTs), central giant cell lesions (CGCLs), ameloblastomas, and metastatic lesions, that were submitted for biopsy along with associated demographics. METHODS Biopsy diagnoses from 9,723 lesions (submitted between 1992 and 2006) were included in this study. Data on lesion location as well as patient demographics were evaluated. RESULTS Thirty types of radiolucent jaw lesions were classified. Nonhealing apical granulomas (40.4%) and cysts (33.1%) occurred at similar rates and together totaled 73% of all biopsied lesions. The majority of reported granulomas and cysts occurred in the anterior maxilla (>36% in each category). The frequency of KOTs (8.8%), CGCLs (1.3%), ameloblastomas (1.2%), and metastatic lesions (<1%) are to be noted along with their location, which was predominately in the posterior mandible. The occurrence of apical cysts, ameloblastomas, KOTs, and metastatic lesions were seen slightly more in men, at 56%, 54%, 55%, and 68%, respectively. The occurrence of CGCLs was seen slightly more in women at 56%, whereas apical granulomas were equally present in men and women. CONCLUSIONS Most nonhealing lesions submitted for biopsy were classified as granulomas or cysts (73%) often from the anterior maxillary jaw. Nonhealing radiolucent jaw lesions other than granulomas or cysts were reported over 20% of the time and may have more severe pathological implications, suggesting the value of differential diagnoses.

Adrenergic regulation of capsaicin-sensitive neurons in dental pulp

Alpha adrenergic agonists (e.g. vasoconstrictors) represent one of the most commonly used drug classes in dentistry. Although adrenergic agonists have potent vascular effects, recent studies suggest that capsaicin-sensitive nociceptors may express adrenoceptors, suggesting that these drugs may directly modulate the function of an important class of pain-signaling neurons in peripheral tissues. In this study, we tested the hypothesis that adrenergic agonists inhibit activation of peripheral terminals of capsaicin-sensitive fibers innervating dental pulp. Pretreatment with epinephrine or clonidine significantly inhibited capsaicin-evoked release of immunoreactive calcitonin gene-related peptide from superfused bovine dental pulp. These studies suggest that adrenergic agonists may reduce postoperative pain in part via a direct inhibition of capsaicin-sensitive nociceptors. This finding may lead to the development of selective, peripherally acting, adrenergic analgesics. Moreover, because neuropeptide release alters blood flow, it is possible that the vascular effects of these drugs are caused by both vasoconstriction and inhibition of peripheral neuropeptide release.