Managing a Deep Subgingival Cusp Fracture: Case Reports.

Cuspal fractures are relatively common. Fortunately for esthetics, when a cuspal fracture occurs in a maxillary premolar, it most commonly involves the palatal cusp. Fractures with a favorable prognosis may be approached with a minimally invasive treatment to successfully retain the natural tooth. This report describes 3 cases of "cuspidization" to treat maxillary premolars with cuspal fractures. After identifying a palatal cusp fracture, the fractured segment was removed, resulting in a tooth that closely resembles a cuspid. Depending on the extent and location of the fracture, root canal treatment was indicated. Subsequently, conservative restorations sealed the access and covered exposed dentin. Full coverage restorations were neither required nor indicated. The resulting treatment provided practical and functional treatment with a good esthetic outcome. When indicated, the described cuspidization technique can conservatively manage patients with subgingival cuspal fractures. The procedure is minimally invasive and cost-effective and can be done conveniently in routine practice.

Nocturnal pollinators strongly contribute to pollen transport of wild flowers in an agricultural landscape.

Dramatic declines in diurnal pollinators have created great scientific interest in plant-pollinator relationships and associated pollination services. Existing literature, however, is generally focused on diurnal pollinating insect taxa, especially on Apidae (Hymenoptera) and Syrphidae (Diptera) pollinators, while nocturnal macro-moths that comprise extremely species-rich flower-visiting families have been largely neglected. Here, we report that in agricultural landscapes, macro-moths can provide unique, highly complex pollen transport links, making them vital components of overall wild plant-pollinator networks in agro-ecosystems. Pollen transport occurred more frequently on the moths' ventral thorax rather than on their mouthparts that have been traditionally targeted for pollen swabbing. Pollen transport loads suggest that nocturnal moths contribute key pollination services for several wild plant families in agricultural landscapes, in addition to providing functional resilience to diurnal networks. Severe declines in richness and abundance of settling moth populations highlight the urgent need to include them in future management and conservation strategies within agricultural landscapes.

Vertical root fracture: Factors related to identification.

BACKGROUND: Vertical root fracture (VRF) requires root removal. Diagnostics for proper identification are critical. The author conducted a study to relate subjective, objective, and radiographic findings for VRF identification. They noted visual changes of root and overlying bone patterns after flap reflection. METHODS: The author examined a case series of roots with suspected VRF after flap reflection and root or root-end removal; 42 roots were identified with a fracture. Before reflection, the author obtained diagnostic and periapical radiographic data that included symptoms, soft-tissue changes, percussion, mobility, probing patterns, and radiographic findings. After flap reflection, the author evaluated bony changes and root surfaces. VRF was visually confirmed after tooth or root removal. RESULTS: Signs and symptoms diagnostic of VRF were inconsistent. All patients had endodontic therapy, many with posts, and for all patients, the pain was none to mild. In addition, the author found a history or presence of swelling (77%) or sinus tract (31%), that probing patterns differed (narrow-rectangular 66%), and that there was no defect in some patients (21%). Radiographic patterns varied from no change to extensive bone loss, and mobility ranged from none (55%) to slight or moderate (45%). Flap reflection revealed a "punched-out" bony lesion with granulomatous tissue (100%), and patterns were fenestration (21%) or dehiscence (79%). A fracture was visible on roots or resected root ends. CONCLUSIONS: The author found no consistent signs, symptoms, or radiographic changes of VRF. Flap reflection was found to be predictably useful; fractured roots had bony defects filled with granulomatous tissue. PRACTICAL IMPLICATIONS: VRF may be suspected from clinical findings; however, flap reflection is usually required for identification. Characteristic bony pattern and root visualization reveals the fracture, although root-end resection and examination is occasionally required.

Histologic examination of condensing osteitis in cadaver specimens.

OBJECTIVES: Condensing osteitis is a radiographic finding, but with no reported histologic investigations in humans. The objectives of this study were to evaluate and describe histologically condensing osteitis in human cadaver jaws. Patterns of bone formation and presence/absence and nature of inflammation were examined. METHODS: Specimens of mandibles and maxillas were obtained from cadavers and examined radiographically. Those periapical areas with characteristics of condensing osteitis were removed en bloc, decalcified, and processed for light microscopy. For comparison, specimens that showed normal apical radiographic anatomy were also removed for examination. RESULTS: Normal apical regions showed an intact periodontal ligament and a thin layer of alveolar bone proper surrounded by cancellous bone with fatty marrow. In contrast, areas of condensing osteitis exhibited areas of inflammation or no inflammation, occupied by connective tissue. This area was bordered by a rim of varying widths of dense lamellar-type bone replacing the cancellous bone and marrow. CONCLUSIONS: The histologic changes of condensing osteitis consisted of the replacement of cancellous bone with compact bone. Areas of fibrosis and an inflammatory infiltrate were seen in some but not all specimens. All teeth exhibiting condensing osteitis had an identifiable etiology that likely resulted in degenerative pulp disease.

Outcomes.

Outcomes encompass multiple factors, not just success and failure. They include other considerations such as being workable and profitable to the dentist and safe and acceptable to the patient. The more biological outcomes are most frequently measured. These measurements are on a scale from least to most predictable outcomes of treatment by the dentist, as shown on the evidence pyramid. Impact trauma is an example of a general scarcity of high-level evidence with treatment because of the nature and individuality of the injuries and the difficulty (or impossibility) of designing controlled clinical trials in humans. Much of the evidence is cohort (retrospective or observational studies), case reports, animal studies, and "expert" opinion. Thus, guidelines are largely based on lower levels of evidence. Nonetheless, the current guidelines provide the clinician with the best evidence that is available. The best opportunity for randomized controlled trials is in prevention. Specifically, mouthguard design and usage can be subjected to higher levels of controlled research. Revitalization and regeneration are relatively new procedures. To date, there is a lack of high levels of evidence to be able to substantiate whether these are clinically feasible to become a routine in practice.

Outcomes.

Outcomes encompass multiple factors, not just success and failure. They include other considerations such as being workable and profitable to the dentist and safe and acceptable to the patient. The more biological outcomes are most frequently measured. These measurements are on a scale from least to most predictable outcomes of treatment by the dentist, as shown on the evidence pyramid. Impact trauma is an example of a general scarcity of high-level evidence with treatment because of the nature and individuality of the injuries and the difficulty (or impossibility) of designing controlled clinical trials in humans. Much of the evidence is cohort (retrospective or observational studies), case reports, animal studies, and "expert" opinion. Thus, guidelines are largely based on lower levels of evidence. Nonetheless, the current guidelines provide the clinician with the best evidence that is available. The best opportunity for randomized controlled trials is in prevention. Specifically, mouthguard design and usage can be subjected to higher levels of controlled research. Revitalization and regeneration are relatively new procedures. To date, there is a lack of high levels of evidence to be able to substantiate whether these are clinically feasible to become a routine in practice.

Patient preferences regarding 1-visit versus 2-visit root canal therapy.

INTRODUCTION: Patient preferences should be taken into account by clinicians when treatment planning. The purposes of this study were to describe the number of visits patients preferred when undergoing root canal therapy (RCT) and to assess whether their preferences were related to hypothetical treatment success rates. METHODS: Self-administered questionnaires were mailed to 351 consecutive patients scheduled for initial RCT appointments in the University of Iowa College of Dentistry's graduate or faculty endodontic clinic. The questionnaires ascertained demographic information; preferences for 1-visit versus 2-visit RCT given different hypothetical success rate scenarios for the 2 approaches, as well as patient dental history. Univariate frequency distributions were generated, and relationships between hypothetical success rates and patient preferences were evaluated. RESULTS: Questionnaires were returned by 124 patients (35% response). Given equal success rates, 78% of respondents preferred 1-visit RCT, compared with 7% who preferred 2-visit RCT and 16% who would follow their dentist's recommendation. As success rates for 2-visit RCT went from equal to 5% better to 10% better to 20% better compared with 1-visit RCT, the proportion of respondents who preferred 2-visit RCT increased from 7% to 34% to 46% to 65%, respectively. Regardless of success rates, approximately 5% of respondents said they would prefer 2-visit RCT, and 20% would do whatever their dentist recommended. CONCLUSIONS: Although most respondents preferred 1-visit RCT regardless of success rates, many would prefer 2-visit RCT if its success rate were greater than that of 1-visit RCT. This finding confirms the importance of discussing success rates and considering patients' wishes when treatment planning.

Identify and define all diagnostic terms for periapical/periradicular health and disease states.

INTRODUCTION: The purpose of this in-depth investigation was to identify, clarify, and substantiate clinical terminology relative to apical/periapical/periradicular diagnostic states, which is used routinely in the provision of endodontic care. Furthermore, the information gleaned from this investigation was used to link diagnostic categories to symptoms, pathogenesis, treatment, and prognosis wherever possible, along with establishing the basis for the metrics used in this diagnostic process. MATERIALS AND METHODS: Diagnostic terminologies and their relevance to clinical situations were procured from extensive historic and electronic searches and correlated with contemporary concepts in disease processes, clinical assessments, histologic findings (if appropriate), and standardized definitions that have been promulgated and promoted for use in the last 25 years in educational programs and test constructions and for third-party concerns. RESULTS: In general, clinical terminology that is used routinely in the practice of endodontics is not based on the findings of scientific investigations. The diagnostic terms are based on assumptions by correlating certain signs, symptoms, and radiographic findings with what is presumed (not proven) to be the underlying disease process of a given clinical state. There were no studies that specifically tried to assess the accuracy of the metrics used contemporarily for the classification of clinical disease states. CONCLUSION: A succinct diagnostic scheme that could be described thoroughly, agreed on unanimously, coded succinctly for easy electronic input, and ultimately used for follow-up analysis would not only drive treatment modalities more accurately, but would also allow for future outcomes assessment and validation.

Resin-based versus gutta-percha-based root canal obturation: influence on bacterial leakage in an in vitro model system.

OBJECTIVE: This study evaluated the ability of a resin-based system (Resilon/Epiphany) and gutta-percha/sealer with warm vertical or cold lateral compaction to prevent coronal leakage. STUDY DESIGN: A polymicrobial suspension in a dual-chamber model was used. Seventy extracted maxillary incisors were prepared, divided into 4 groups, and obturated: Group 1, lateral compaction/gutta-percha/AH Plus; Group 2, lateral compaction/Resilon; Group 3, continuous wave compaction/gutta-percha/AH Plus; Group 4, continuous wave compaction/Resilon. Upper chambers held a mixed suspension of endodontic pathogens. Apices were suspended in the lower chambers. Leakage was determined daily for 40 days and evaluated for turbidity. Data were analyzed using survival analysis; log-rank test was used to analyze differences in time to leakage. RESULTS: Median time to leakage: 16, 15, 11, and 25 days for Groups 1 to 4 respectively (P = .93, log-rank test). CONCLUSION: No difference in time to leakage among the 4 treatment groups existed.

Vital signs of the emergency patient with pulpal necrosis and localized acute apical abscess.

Vital signs aid in assessing patient health and the disease severity. The objectives of this study were to determine changes in vital signs of patients with pulpal necrosis (PN) and acute apical abscess (AAA). The vital signs measured at the emergency visit were blood pressure, heart rate, temperature, and lymphadenopathy. Visual analogue scales (VASs) were used to assess (1) pain and (2) malaise. Emergency treatment was rendered. At a subsequent (baseline) visit and with clinical symptoms resolved, systemic vital sign measurements and VASs were repeated. The presence or absence of swelling with vital signs and VASs of pain and swelling were compared. Compared with baseline, data showed no marked elevation in temperature, blood pressure, or lymphadenopathy, regardless of presence or absence of swelling. VAS measurements of pain and malaise did show statistically significant higher numbers at the emergency appointment, indicating a difference from baseline. Swelling versus no swelling did not differ. Vital signs were not impacted by localized AAA, although pain and malaise were greater. Vital signs might not be useful determinants of treatment or pharmacotherapeutic measures with localized AAA.

Evaluation of intracanal sealer distribution with 5 different obturation techniques.

OBJECTIVE: The aim of this study was to determine the distribution patterns of sealer relative to the gutta-percha and the canal wall following the use of different obturation techniques: vertical condensation, Obtura II, System B, SimpliFill, and Thermafil Plus; lateral condensation was used as a comparison. METHODS AND MATERIALS: One hundred five extracted single-rooted teeth were divided into 5 groups of 20 according to obturation technique, with 5 in the lateral condensation group. Instrumentation technique and sealer selection were based on the manufacturer's recommendations. Following obturation, teeth were stored for 4 months at 37 degrees C in 100% humidity. Roots were split longitudinally and halves were examined under a stereomicroscope (x 10) to determine the amount of sealer coverage between the gutta-percha and canal wall. Coverage was categorized as slight (0 to 1/3), low partial (1/3 to 2/3), high partial (2/3 to 9/10), and complete (9/10 to 10/10). RESULTS: Different techniques showed different patterns, but no obturation technique had sealer forming a continuous layer between the gutta-percha and canal wall. The vertical condensation group generally had low partial coverage. Obtura II was the only group to have slight coverage, which occurred in the coronal half. Coronal and apical halves in both the System B and Thermafil Plus groups had the most samples with high partial coverage. SimpliFill had the most samples with complete coverage in both the coronal and the apical portions. All lateral condensation samples showed low partial coverage. CONCLUSION: Sealer distribution patterns were incomplete and inconsistent, regardless of the obturation technique. No technique had sealer forming a continuous layer between the gutta-percha and canal wall.

Effect of root canal filling/sealer systems on apical endotoxin penetration: a coronal leakage evaluation.

Endotoxin, elaborated by gram-negative organisms, is an important factor in apical periodontitis. The objective of this study was to evaluate the magnitude of endotoxin penetration through root canal treated teeth using a dual chamber model system. Forty-four maxillary anterior teeth were prepared endodontically and canals filled either by lateral condensation or a warm thermoplasticized technique in combination with either Roth's 801 or AH 26 sealer. Teeth were suspended in the model system with a mixed anaerobic bacterial suspension in the upper chamber and HBSS in the lower chamber. The QCL-1000 LAL assay was used to measure endotoxin at 0, 1, 7, 14, and 21 days. Response feature analysis using trapezoidal area under the curve was performed; the four treatment groups were compared using nonparametric methods. Groups differed (p = 0.028), with thermoplasticized root canal filling/Roth's 801 sealer permitting the least apical endotoxin penetration. Results suggest that Roth's 801 sealer may have a role in inhibiting endotoxin penetration.

Determining the optimal obturation length: a meta-analysis of literature.

The purpose was to aid in determining termination of instrumentation and obturation. A meta-analysis was conducted as to success/failure of different obturation lengths. Inclusion criteria were (a) minimum follow-up of 2 yr, (b) data on obturation length, (c) definition of success/failure, (d) available data on success/failure, (e) radiographic evaluation. Correlations were made as to success/failure as related to length of obturation from the apex. When comparing group A (obturated 0-1 mm from apex) versus group C (obturated past apex) using the DerSimonian and Laird estimates, group A showed a marginally better (p < 0.10) success rate than group C by 28.8%. Group A had better success than group B (obturated >1 mm short); the difference was insignificant. The results were similar after controlling for study quality using a single random effects regression model. In conclusion, the meta-analysis indicated that a better success rate is achieved when treatment includes obturation short of the apex.

Intracanal distribution patterns of sealers after lateral condensation.

The purpose of this study was to examine coverage patterns of sealer on canal walls and between gutta-percha cones after lateral condensation. Ninety extracted teeth with single canals were evenly and randomly divided into three sealer groups (Roth's, Sealapex, AH 26). Canals were cleaned and shaped, then coated with one of the three sealers followed by lateral condensation of gutta-percha. The teeth were placed into 100% humidity at 37 degrees C. After 4 months the roots were notched and fractured longitudinally and the dentin lifted to expose the gutta-percha sealer and dentin walls. Qualitative assessment was in the apical and coronal as to the amount and the pattern of sealer coverage. Coverage was categorized by the amount and location as follows: (a) no sealer; (b) slight-partial; (c) moderate-partial; or (d) complete coverage. Sealer was frequently absent between gutta-percha cones and the canal wall and at times absent between cones, with a general moderate-partial coverage. No sealer group demonstrated complete coverage; however, AH 26 showed more consistent moderate-partial distribution. Coverage was better in the coronal. In conclusion, none of the three sealers showed a continuous layer between the primary gutta-percha obturant and the canal wall or in spaces between cones.

Calcium hydroxide as an intracanal medication: effect on posttreatment pain.

Calcium hydroxide is advocated as an intracanal medication for various purposes, including prevention of posttreatment symptoms. This study assessed whether calcium hydroxide had a pain-controlling effect at different times when compared with no intracanal medication. One hundred forty patients participated. Conditions diagnosed were pulp/periapical pathosis with or without symptoms. At least partial cleaning and shaping was completed. At random, either Ca(OH)2 plus H2O paste or a dry cotton pellet was placed in the canals of half the teeth, respectively. All teeth were temporized with Intermediate Restorative Material. Patients assessed posttreatment pain up to 48 h as none, mild, moderate, or severe. The pain levels in each test group [Ca(OH)2 versus cotton pellet] at each time period were compared statistically with a multiple-regression analysis. There was no significant difference in posttreatment pain between the two groups at any time period or with any diagnosis or symptom. The use of calcium hydroxide as an intracanal medication was unrelated to the incidence and/or severity of posttreatment pain.

Comparison of carbon dioxide versus refrigerant spray to determine pulpal responsiveness.

There is little evidence for which cold delivery method is most accurate in determining pulp responsiveness. This study compared carbon dioxide dry ice sticks (CO2) versus refrigerant spray (RS) to generate a patient response from different types of teeth restored to varying degrees. Fifteen human patients were selected. In each quadrant, three teeth were identified and the restoration type recorded. Blindfolded patients were randomly tested with either CO2 or RS in a crossover design at two different sessions. Responsiveness was recorded as yes/no and the interval (in seconds) from application to response was determined. Results showed that (a) CO2 and RS were equivalent in producing a pulpal response regardless of tooth and presence of restoration, and (b) CO2 took significantly (p < 0.05) longer to evoke a response than RS using paired t tests. In conclusion, RS and CO2 were equivalent in determining pulpal responsiveness, but the elicited response from RS was faster.

Sealer distribution in coronal dentin.

A major cause of tooth discoloration is sealer remnants in the pulp chamber after root canal treatment. The purpose of this study was to assess coronal distribution and color changes of four commonly used sealers placed in the pulp chamber after 2 yr. Fifty extracted premolars were cross-sectioned in the coronal third of the root. The chamber contents were removed, and instrumentation was via the canal; then freshly mixed sealer was placed in each chamber. Sealers evaluated were: AH 26, Kerr Pulp Canal Sealer, Roth 801, and Sealapex. The apical access was sealed with white sticky wax, and the tooth was maintained in a moist environment at 37 degrees C for 2 yr. Teeth were split longitudinally, and digital images of the exposed dentin were made, scrambled, and evaluated blindly by trained evaluators for color changes and for presence of sealer in dentin. There was no measurable penetration of sealer into dentin for all groups and no dentin discoloration occurred. The sealers displayed marked discoloration. At 2 yr, the sealers discolored and remained confined primarily to the pulp chamber.

Straight line access and coronal flaring: effect on canal length.

The object of this study was to determine if canal length is altered as a result of straight-line access (SLA) and coronal flaring (CF). Selected were 86 canals of extracted molars and premolars from two groups: straight or severely curved (Schneider curvature <5 degrees and >20 degrees). The reference cusp tip and root-end were flattened to produce reproducible measurements. A #10 file was placed such that the tip extended slightly beyond the apex, with the handle on the referenced cusp. The amount of file protrusion was measured with a stereomicroscope. Then, SLA and CF were performed and the corresponding file replaced to the same coronal reference position. Apical file protrusion was measured again. The change in canal length was determined by the difference in the pre- and post-SLA/CF measurements. A Wilcoxon signed rank test statistically verified that there was a measurable, significant (p < 0.001) change in canal length after SLA and CF. The mean change overall was slight, with a decrease of 0.17 mm. Severe curvature had a slightly greater, significant effect on the amount of change. Tooth type had no significant effect. Changes in working length from SLA and CF, although statistically significant, were very small and clinically unimportant.