Long-term performance of ceramic in/-onlays vs. cast gold partial crowns - a retrospective clinical study.

OBJECTIVES: To assess the long-term clinical performance of ceramic in-/onlays (CIOs) and cast gold partial crowns (CGPCs) in posterior teeth in terms of success, survival, complications (biological, technical) and quality. MATERIAL AND METHODS: In a retrospective study, a total of 325 patients were recorded after up to 24.8 years (mean 13.9 ± 3.8 years) having (pre-)molars restored with CIO (Empress I, Ivoclar Vivadent, n = 161) and CGPC (Degunorm, DeguDent, n = 164) by supervised undergraduate students. A total of 296 restorations were assessed clinically and radiologically in healthy and endodontically treated teeth using modified United States Public Health Service (USPHS) criteria. Cumulative success and survival rates of the restorations were calculated using Kaplan-Meier estimates. Biological and technical complications were recorded. Status of oral health comprising caries risk and localized periodontitis were assessed. RESULTS: The cumulative success rates of CIOs were 92.1% and of CGPCs 84.2% after mean service times of 14.5 years. The annual failure rates of total service times were 0.5% in teeth restored with CIO (n = 155) and 0.7% in teeth restored with CGPC (n = 163). The cumulative survival rates of CIOs were 93.9% after a mean service time of 15.2 years and decreased to 91.7% after 23.5 years. The cumulative survival rates of CGPCs were 92.6% after a mean service time of 14.9 years and 91.8% after 23.5 years. Complications in CIOs (n = 149) were ceramic fracture (6.7%), secondary caries (4.7%), endodontic complication (2.7%) and tooth fracture (1.3%) compared to CGPCs (n = 147) with endodontic complication (8.8%), secondary caries (4.8%) and decementation (2.0%). Endodontically treated teeth restored with CIO or CGPC revealed significantly less often success compared with corresponding vital teeth (p = .02). CIOs and CGPCs revealed clinically and radiographically good and excellent qualities with 71.8% (107/149) and 68% (100/147) without any significant differences regarding type of restoration. CONCLUSIONS: Both CIOs and CGPCs achieved high survival rates up to 24.8 years when performed by supervised undergraduate students. The longevity of the restorations may benefit from the intraoral repair of accessible defects and, in case of pulp infection or necrosis, an adequate endodontic management. CLINICAL RELEVANCE: CIOs and CGPCs made by supervised undergraduate students are proper restoration types in posterior teeth in the long-term. An adequate preparation design, meticulous care in the inserting technique and constant biofilm removal due to proper oral hygiene combined with professional maintenance care are substantial. The clinical long-term performance was mostly limited by ceramic fractures in CIOs and endodontic complications in CGPCs.

Tooth discoloration induced by apical plugs with hydraulic calcium silicate-based cements in teeth with open apices-a 2-year in vitro study.

OBJECTIVES: To assess tooth discoloration induced by different hydraulic calcium silicate-based cements (HCSCs), including effects of blood and placement method. MATERIALS AND METHODS: Eighty bovine teeth cut to a length of 18 mm (crown 8 mm, root 10 mm) were randomly assigned to 10 groups (n = 8), receiving orthograde apical plug treatment (APT). Apical plugs were 4 mm in length and made of ProRoot MTA (Dentsply), Medcem MTA (Medcem), TotalFill BC RRM Fast Set Putty (Brasseler), or Medcem Medical Portland Cement (Medcem) plus bismuth oxide (Bi2O3) with and without bovine blood. Further, orthograde (with or without preoperative adhesive coronal dentin sealing) and retrograde APT were compared. Teeth were obturated with gutta-percha and sealer, sealed with composite and stored in distilled water. Tooth color was measured on apical plug, gutta-percha/sealer, and crown surface before treatment versus 24 h, 1, 3, 6, 12, and 24 months after treatment by spectrophotometry. Color difference (ΔE) values were calculated and analyzed by Shapiro-Wilk test, ANOVA with post hoc tests, Friedman test, t test, and post hoc tests with Bonferroni correction (α = .05). RESULTS: Tooth discoloration occurred in all groups with no significant differences between HCSCs (p > .05). After 24 months, color changes were prominent on roots but insignificant on crowns. Blood contamination induced a significantly decreased luminescence (p < .05). Blood had a stronger impact on tooth color than Bi2O3. No relevant effects of retrograde placement (p > .05) or preoperative dentin sealing (p > .05) were detected. CONCLUSIONS: Apical plugs of the tested HCSCs cause discoloration of bovine roots, but not discoloration of bovine tooth crowns within a 24-month period. CLINICAL RELEVANCE: APT should be performed carefully while avoiding direct contact with the coronal dentin, and in that case no aesthetic impairments occur.

Long-term outcome of adhesive fragment reattachment in crown-root fractured teeth.

BACKGROUND/AIMS: Adhesive fragment reattachment (AFR) is one treatment option for crown-root fractured teeth. However, there are no studies investigating the long-term outcome of this approach. The aim of this retrospective study was to evaluate the long-term outcome of AFR and periodontal health in crown-root fractured teeth by assessing complications and periodontal status. MATERIALS AND METHODS: Data regarding 41 patients with 51 traumatized teeth (TT) were included. Periodontal health was assessed by recording the pocket probing depth (PPD), clinical attachment level (CAL), bleeding on probing (BoP), gingival index (GI), and plaque index (PI) in the TT and in one unaffected control tooth (CT). Complications were classified as "restorative," "endodontic," and "additional root fracture." Based on these complications, the outcome was graded as "success," "partial success," "survival," and "failure." Statistics was performed by t test, chi-square test and logistic regression models. RESULTS: After 8.5 ± 4.6 years, 76.5% (39/51) of the TT had functionally survived. Functional survival of the reattached fragments was 66.7% (26/39) after 9.5 ± 3.7 years. PPD (TT: 4.11 ± 2.03; CT: 2.08 ± 0.65), CAL (TT: 4.78 ± 2.19; CT: 2.42 ± 1.03), and BoP values (TT: 77.4%; CT: 22.6%) were higher in TT than in CT. GI scores > 0 were found in 83.3% of the TT and in 27.8% of the CT. PI scores did not differ between TT and CT. Of the complications, 56.8% were "restorative," 22.7% "endodontic," and 20.5% "additional root fractures." Eleven (27.5%) TT were without complications and rated as "success." CONCLUSIONS: AFR in crown-root fractured teeth showed a high survival rate and occasionally compromised periodontal health. However, due to the high complication rate, it should be considered as a long-term temporary treatment to postpone other invasive therapy options. AFR can be a valuable way to avoid early loss of crown-root fractured teeth, especially in young patients. Moisture control and additional root fractures significantly influenced the outcome.

Guided endodontics: a comparative in vitro study on the accuracy and effort of two different planning workflows.

AIM: To compare the accuracy and effort of digital workflow for guided endodontic access (GEA) procedures using two different software applications in 3D-printed teeth modeled to simulate pulp canal obliteration (PCO) in vitro. MATERIALS AND METHODS: 32 3D-printed incisors with simulated PCO were fabricated and mounted, four each on maxillary and mandibular study arches. Cone beam computed tomography (CBCT) and 3D surface scans were matched and used to virtually plan and prepare GEA by one operator using two different methods: 1) CoDiagnostiX (CDX; Dental Wings) with 3D-printed templates, and 2) Sicat Endo (SE; Sicat) with subtractive CAD/CAM-manufactured templates. Postoperative CBCT and virtual planning data were superimposed for analysis. Accuracy was assessed by measuring the discrepancies between planned and prepared cavities at the tip of the bur (three spatial dimensions, 3D vector, angle). Virtual planning effort was defined as the time and number of computer clicks. A 95% confidence interval (CI) was computed for each sample. RESULTS: SE successfully located root canals for GEA in 16/16 cases (100%) and CDX in 15/16 cases (94%). SE resulted in less mean deviation at the tip of the bur with regard to distance in the labial-oral direction (0.12 mm), 3D vector (0.35 mm), and angle (0.68 degrees) compared with CDX (0.54 mm, 0.74 mm, 1.57 degrees, respectively; P < 0.001). CDX required less mean planning time and effort for each four-tooth arch (10 min 50 s, 107 clicks) than SE (20 min 28 s, 341 clicks; P < 0.05). CONCLUSIONS: Both methods enabled rapid drill path planning, a predictable GEA procedure, and the reliable location of root canals in teeth with PCO without perforation.

Long-term retention of avulsed maxillary permanent incisors replanted after prolonged non-physiological storage.

Ankylosis and external replacement resorption (ERR) are two typical biological responses to delayed replantation of avulsed teeth in cases where adequate root canal treatment is performed. The patient's growth stage affects the progression of root resorption and the long-term outcome of the affected teeth. This case report describes the long-term outcome of an 18.5-year-old patient following an accident in which both of his maxillary central incisors were avulsed and replanted after four hours of non-physiological storage. ERR and ankylosis of teeth 11 and 21 were detected clinically and radiographically during the second year of follow-up. Sixteen years after replantation, replacement resorption was progressing very slowly, enabling functional tooth retention with favorable esthetics. Young adults, with delayed replantation of avulsed teeth, may benefit from tooth retention with slow ERR.

Outcome of non-surgical root canal treatment related to periodontitis and chronic disease medication among adults in age group of 60 years or more.

OBJECTIVE: To assess the impact of non-endodontic factors like periodontitis and chronic disease medication (CDM) mostly affecting elderly people's health on the outcome of non-surgical root canal treatment (NSRCT). BACKGROUND: An increasing number of elderly people with high prevalence of marginal periodontitis and CDM benefit from adequate endodontic therapy, if irreversible pulpitis or apical periodontitis occurs. Only few data exist about the relevance of those non-endodontic factors on healing of endodontic lesions in a population 60 years or more. MATERIAL AND METHODS: Of 177 patients aged 60 years or more with 212 NSRCTs performed between the year of 2010 and 2013, complete documentation was available for 112 teeth in 93 participants. Mean time between baseline and last follow-up was 38.93 months. The primary endodontic factors studied were the periapical index (PAI) of periapical health, quality of the root canal filling and of coronal restoration, periodontal probing depth (PPD, mm) and tooth mobility (TM, 0-3). Secondary non-endodontic factors included the presence of marginal periodontitis and CDM, in particular antidiabetics, antihypertensives and anticoagulants. Statistical analyses were performed using Chi-square test statistics and logistic regression analysis. RESULTS: Periodontitis and CDM had no effect on endodontic outcome. Chronic intake of anticoagulants showed a significant association with endodontic outcome. Root-filled teeth with preoperative periapical lesions had a significantly higher rate of endodontic failure than those without preoperative lesion. The overall success rate of NSRCT was 87.1% with 81 healed teeth. CONCLUSION: Periodontitis and CDM have no impact on the endodontic outcome of NSRCT in a population 60 years or more.

Surgical extrusion with an atraumatic extraction system: A clinical study.

STATEMENT OF PROBLEM: Clinical studies evaluating the feasibility of a novel technique for the surgical extrusion of nonrestorable teeth with subgingival caries are lacking. PURPOSE: The purpose of this clinical study was to investigate the success rate and incidence of biological and technical complications after tooth extrusion with an atraumatic extraction system (AES). MATERIAL AND METHODS: Participants were recruited from 61 consecutive patients initially referred to a specialist oral surgery practice. Fifty-one participants who underwent surgical extrusion with an AES followed by endodontic treatment and coronal restoration could be re-evaluated clinically and radiographically. RESULTS: The mean observation period was 3.1 years (range: 0.8 to 6.5 years). The participants varied in age between 24.8 and 86.3 years. The amount of extrusion was between 2.5 and 5.0 mm (mean 3.2 mm). At recall, 92.2% (47 of 51) of the extruded teeth were considered successful. All extruded teeth were asymptomatic, without clinical signs of inflammation. Percussion appeared normal and did not differ from that of the adjacent teeth, indicating absence of ankylosis. Transient resorption with a slightly altered root contour was detected in 5 of the 51 teeth. Minor reduction of the bone level (less than 10%) was detected in 8 of the 51. In a further 2 teeth, bone loss amounted to 25% and 30%. Periapical periodontitis at recall was seen in 4 of the 51 teeth, and a preexisting periapical lesion healed in 10 of 13. Root perforation was identified in 3 of the 51, and a further 3 of 11 were not available for recall. Thus, the technical complication rate was 9.7% (6 of 62). CONCLUSIONS: The AES may be successfully used for surgical extrusion to save apparently nonrestorable teeth, irrespective of patient age.

Root Maturation of an Immature Dens Invaginatus Despite Unsuccessful Revitalization Procedure: A Case Report and Recommendations for Educational Purposes.

BACKGROUND: The clinical management of teeth with complex dens invaginatus (DI) malformations and apical periodontitis may be challenging due to the lack of routine. The aim of this case report is to describe the endodontic treatment of an immature tooth with DI and to discuss strategies for preclinical training for teeth with such malformations. CASE REPORT: A 9-year-old male presented with an immature maxillary incisor with DI (Oehlers Type II) and apical periodontitis which was diagnosed by cone beam computed tomography (CBCT). Revitalization was initially attempted but then abandoned after failure to generate a stable blood clot. Nevertheless, considerable increase in both root length and thickness could be detected after medication with calcium hydroxide followed by root canal filling with MTA as an apical plug. CONCLUSIONS: The endodontic management of teeth with DI requires thorough treatment planning. In immature teeth, under certain conditions, root maturation may occur even with conventional apexification procedures. From an educational perspective, different strategies including CBCT and 3D-printed transparent tooth models for visualization of the complex internal morphology and redesigned 3D-printed replica with various degrees of difficulty for endodontic training, can be used to overcome the challenges associated with endodontic treatment of such teeth.

Endodontic Outcome of Root Canal Treatment Using Different Obturation Techniques: A Clinical Study.

OBJECTIVE: To evaluate the clinical outcome of root canal treatment by obturation technique, root canal filling quality, and tooth- and patient-related variables. METHODS: This clinical study investigated the endodontic outcome of 114 teeth treated between the years 2009 and 2012. Three different obturation methods were used: (1) adhesive obturation using the continuous wave of condensation technique with Resilon® (CWR), (2) matching-taper single-cone technique with gutta-percha and AH Plus® (SCGP), and (3) matching-taper single-cone technique with gutta-percha and GuttaFlow® (SCGF). Pre- and postoperative periapical radiographs were performed to detect the presence of endodontic lesions (PAI classification) and to assess the quality of both the obturation and the restoration. Tooth- and patient-related data were collected. RESULTS: The overall endodontic success rate was 75.4% after a mean observation period of 6.3 years. There were no significant correlations between the type or overall quality of obturation and the treatment outcome. Teeth with preoperative lesions had the highest odds ratio (factor of 4.98) for endodontic failure. Tooth- and patient-related variables had no significant effect on endodontic outcome. CONCLUSIONS: The preoperative periapical status of teeth requiring endodontic treatment was a substantial prognostic factor for endodontic outcome, whereas the type of obturation material or technique did not affect it.

Traumatized teeth: clinical practice guideline for the interim management of teeth with various poor prognosis scenarios in growing patients.

OBJECTIVES: Many treatment options accepted for unsalvageable traumatized teeth in adults would seem contraindicated in children and adolescents. Instead, growing patients need interim restorative measures, thus extensively preserving their local bone and soft tissue structures and, ideally, preparing the involved site for later definitive restoration while they transform to skeletal maturity. This narrative topic review addresses the interim management in case of very deep intra-extra-alveolar fractures, extensive infection-related root resorption, tooth ankylosis, and anterior tooth loss in growing patients, and seeks to empower the clinician to select the appropriate treatment approach. DATA SOURCES: The literature up to 2021 was reviewed based on several scoping searches on PubMed and the Cochrane Library using relevant terms. Due to the complexity of the topic (with various poor prognosis scenarios and the differing therapeutic options), a systematic review was deemed inappropriate. CONCLUSION: Suitable interim treatment options include extrusion of teeth showing deep intra-extra-alveolar fractures, and decoronation of ankylosed teeth as well as resin-bonded fixed dental prostheses, natural tooth pontics, and primary tooth autotransplantations after tooth loss. The interim management options described in this article represent compromises chosen in the absence of better alternatives after a careful risk-benefit analysis. However, if adequately performed, the presented treatment options have the potential to achieve the temporary restoration of function and esthetics in growing patients. Close clinical and (if appropriate) radiologic monitoring of these patients is considered mandatory to ensure early detection of possible complications that might jeopardize or could render impossible subsequent therapeutic measures. (Quintessence Int 2022;53:722-731; doi: 10.3290/j.qi.b3236409; Modified from a previously published article (in German) Quintessenz 2022;73(2):162-169).

Influence of Matrix Type on Marginal Gap Formation of Deep Class II Bulk-Fill Composite Restorations.

Background: To test the hypothesis that transparent matrices result in more continuous margins of bulk-fill composite (BFC) restorations than metal matrices. Methods: Forty standardized MOD cavities in human molars with cervical margins in enamel and dentin were created and randomly assigned to four restorative treatment protocols: conventional nanohybrid composite (NANO) restoration (Tetric EvoCeram, Ivoclar Vivadent, Schaan, Liechtenstein) with a metal matrix (NANO-METAL) versus transparent matrix (NANO-TRANS), and bulk-fill composite restoration (Tetric EvoCeram Bulk Fill, Ivoclar Vivadent, Schaan, Liechtenstein) with a metal matrix (BFC-METAL) versus transparent matrix (BFC-TRANS). After artificial aging (2500 thermal cycles), marginal quality was evaluated by scanning electron microscopy using the replica technique. Statistical analyses were performed using the Mann−Whitney U-test and Wilcoxon test. The level of significance was p < 0.05. Results: Metal matrices yielded significantly (p = 0.0011) more continuous margins (46.211%) than transparent matrices (27.073%). Differences in continuous margins between NANO (34.482%) and BFC (38.802%) were not significant (p = 0.56). Matrix type did not influence marginal gap formation in BFC (p = 0.27) but did in NANO restorations (p = 0.001). Conclusion: Metal matrices positively influence the marginal quality of class II composite restorations, especially in deep cavity areas. The bulk-fill composite seems to be less sensitive to the influence of factors such as light polymerization and matrix type.

Influence of filler geometry and viscosity of composite luting materials on marginal adhesive gap width and occlusal surface height of all-ceramic partial crowns.

OBJECTIVES: To evaluate the influence of filler geometry and viscosity of luting composites on marginal adhesive gap width (MGW) and occlusal surface height (OSH) of all-ceramic partial crowns. METHODS: Forty-eight all-ceramic partial crowns (Celtra Duo, Dentsply) were created and divided into six groups (n = 8). Restorations were bonded using universal adhesive (Prime & Bond Active, Dentsply) in combination with low-viscosity composites (LV) containing amorphous fillers (Calibra Ceram, Dentsply) (LV-AF), heterogeneous fillers (Tetric EvoFlow, Ivoclar Vivadent) (LV-HF) vs. high-viscosity composites (HV) containing spherical fillers (Ceram.x, Dentsply) (HV-SF) or heterogeneous fillers (Tetric EvoCeram, Ivoclar Vivadent) (HV-HF). HV materials were used either with or without sonication. MGW [µm] was measured by SEM. Displacements of the restorations after luting, such as changes (Δ) in OSH [µm], tilting and rotation [°], were measured using a dial gauge and 3D-analytical software (OraCeck, Cyfex). Statistical analysis was by Mann-Whitney U-test and t-test with α = 0.05. RESULTS: MGW (p = 0.002) and tilting (p = 0.001) were significantly smaller with LV (228.0 ± 112.35 µm; 0.89 ± 1.25°) than with HV (338.1 ± 97.26 µm; 1.95 ± 1.26°). Sonication had no effect on MGW in HV-HF (332.32 ± 91.39 µm) and HV-SF (343.85 ± 105.48 µm; p = 0.74). Sonication decreased ΔOSH by ~50% with HV-SF (64.21 ± 27.90 µm) but remained unchanged with HV-HF (39.06 ± 14.08 µm; p = 0.004). There was no difference in rotation between HV (0.82 ± 0.81°) and LV (0.61 ± 0.74°; p = 0.29). The LV-AF and LV-HF groups showed no statistical differences in MGW, ΔOSH, tilting or rotation (p > 0.05). SIGNIFICANCE: Irrespective of filler geometry and insertion technique, the use of high-viscosity composites for the adhesive cementation of modern all-ceramic partial crowns increases displacement, marginal misfit and occlusal surface height.

Orthodontic Forced Eruption of Permanent Anterior Teeth with Subgingival Fractures: A Systematic Review.

(1) Background: To assess orthodontic forced eruption (OFE) as a pre-restorative procedure for non-restorable permanent teeth with subgingival dental hard tissue defects after dental trauma. (2) Methods: A systematic electronic search of three databases, namely, MEDLINE, Cochrane Library, and EMBASE, revealed a total of 2757 eligible publications. Randomized controlled clinical trials (RCT), retro- and prospective clinical studies, or case series (with a minimum of three patients) were reviewed. (3) Results: Thirteen full-text papers were included: one RCT, one prospective clinical trial, two retrospective cohort studies, and nine case series. Within case series, statistical significance between age and cause of fracture (p < 0.03) was determined. The mean extrusion rate of OFE was 1.5 mm a week within a four to six weeks treatment period followed by retention. Three OFE protocols for maxillary single teeth are available: 1. OFE without migration of gingiva and alveolar bone, 2. OFE with gingival migration and slight alveolar bone migration, and 3. OFE with migration of both gingiva and alveolar bone. (4) Conclusions: The current state of the evidence suggests that OFE is a feasible pre-treatment option for non-restorable permanent teeth. OFE can promote the migration of tooth surrounding hard and soft tissues in the esthetic zone. Root resorption does not seem to be a relevant side effect of OFE.

Real-Time Guided Endodontics with a Miniaturized Dynamic Navigation System Versus Conventional Freehand Endodontic Access Cavity Preparation: Substance Loss and Procedure Time.

INTRODUCTION: This study aimed to evaluate substance loss and the time required for access cavity preparation (ACP) using the conventional freehand method (CONV) versus a miniaturized dynamic navigation system of real-time guided endodontics (RTGE) in an in vitro model using 3-dimensional-printed teeth. METHODS: Nine human anterior maxillary teeth were selected and micro-computed tomographic scanned. Root canals were virtually reduced to 2 mm below the cementoenamel junction. The teeth were digitally duplicated and mirrored to yield 6 different models with 6 single-rooted teeth each. The models were 3-dimensionally printed using radiopaque resin and consecutively mounted on a dental mannequin for ACP. Two operators with 12 and 2 years of clinical experience, respectively, received 6 models (36 teeth) each and performed ACP on half of the models using RTGE (after digital planning) and CONV on the other half 2 weeks later. The time was recorded. Postoperative substance loss was measured by cone-beam computed tomographic imaging. The differences in time and substance loss between the methods and operators were evaluated by the t test. RESULTS: Overall, substance loss was significantly lower with RTGE than CONV (mean = 10.5 mm3 vs 29.7 mm3), but both procedures took a similar time per tooth (mean = 195 vs 193 seconds). Operator 1 (more experienced) achieved significantly less substance loss than operator 2 with CONV (mean = 19.9 vs 39.4 mm3) but not with RTGE (mean = 10.3 vs 10.6 mm3). CONCLUSIONS: RTGE is a practicable, substance-sparing method performed in comparable time as CONV. Moreover, RTGE seems to be independent of operator experience.

Suitability of Magnetic Resonance Imaging for Guided Endodontics: Proof of Principle.

INTRODUCTION: This proof-of-principle study aimed to demonstrate that magnetic resonance imaging (MRI) is sufficiently accurate for the detection of root canals using guided endodontics. METHODS: One hundred extracted human teeth (anterior and premolar) were mounted onto 5 mandibular and 5 maxillary models, fitted with splints designed to accommodate a thin layer of aqueous gel for indirect imaging, and scanned by MRI. After MRI and intraoral scans were aligned using planning software, access cavities were planned virtually, and templates were manufactured with computer-aided design/computer-aided manufacturing, the access cavities were prepared. Cone-beam computed tomographic scans were performed and matched with the virtual preoperative planning data to determine the accuracy of access cavity preparation in terms of deviation between planned and prepared cavities in the mesiodistal and buccolingual dimensions and angle. Descriptive statistical analysis was performed, and the mean values were compared using the t test. RESULTS: Ninety-one of 100 root canals were successfully scouted after MRI-guided access cavity preparation. The mean angle deviation was 1.82°. The mean deviation ranged from 0.21-0.31 mm at the base of the bur and from 0.28-0.44 mm at the tip of the bur. Preparation in the buccolingual dimension was significantly more precise in mandibular compared with maxillary teeth, and accuracy in the mesiodistal dimension was more precise in anterior teeth compared with premolars. CONCLUSIONS: This in vitro study demonstrated the suitability of MRI for guided endodontic access cavity preparation.

Guided endodontic treatment of multiple teeth with dentin dysplasia: a case report.

BACKGROUND: To report the outcome of guided endodontic treatment (GET) of a case of dentin dysplasia with pulp canal calcification (PCC) and apical periodontitis based on the use of a 3D-printed template designed by merging cone-beam computed tomography (CBCT) and surface scan data. CASE PRESENTATION: A 12-year old female with radicular dentin dysplasia type I (DD-1) presented for endodontic treatment. Radiography revealed PCC in all teeth and apical radiolucency in seven teeth (12, 15, 26, 31, 32, 36 and 46). Tooth 36 had the most acute symptoms and was thus treated first by conventional access cavity preparation and root canal detection. Despite meticulous technique, the distal and mesiolingual canals were perforated. The perforations were immediately repaired with mineral trioxide aggregate, and the decision was made to switch to guided endodontic treatment for the remaining 6 teeth. CBCT and intraoral surface scans were acquired and matched using coDiagnostix planning software (Dental Wings Inc.), the respective drill positions for root canal location were determined, and templates were virtually designed and 3D-printed. The template was positioned on the respective tooth, and a customized drill was used to penetrate the calcified part of the root canal and perform minimally invasive access cavity preparation up to the apical region. All root canals were rapidly and successfully located with the templates. At 1-year follow-up, clear signs of apical healing were present in all treated teeth. CONCLUSIONS: In patients with dentin dysplasia, conventional endodontic therapy is challenging. GET considerably facilitates the root canal treatment of teeth affected by dentin dysplasia.

Intentional Replantation with an Atraumatic Extraction System in Teeth with Extensive Cervical Resorption.

External cervical resorption (ECR) often renders a tooth nonrestorable, especially if it extends deeply within the dental hard tissue. Intentional replantation is sometimes performed as the last resort to save the tooth but may limit conventional forceps extraction because of the high risk of periodontal ligament cell damage or crown fracture.This case report describes the intentional replantation of an upper central incisor with extensive ECR using an axial, atraumatic extraction system to save the otherwise hopeless tooth. The patient was an asymptomatic 37-year-old man with no contributing medical history. The treatment protocol included atraumatic extraction followed by granulation tissue removal, extraoral root canal treatment, and adhesive restoration of the extensive resorption defect. During extraoral manipulation, the utmost care was taken to prevent root surface drying, contamination with dental adhesive, or heat-induced periodontal ligament damage during curing. Two and a half years after replantation, clinical and radiographic examinations revealed normal healing and no symptoms but a slight reduction of bone level compared with the preoperative level and no signs of root resorption or ankylosis. The successful outcome in this case supports the idea of performing intentional replantation with an atraumatic extraction system to save teeth with extensive cervical root resorption and a high risk of fracture during extraction.

Restoring the unrestorable! Developing coronal tooth tissue with a minimally invasive surgical extrusion technique.

Surgical extrusion is a recognised treatment option for teeth that have insufficient coronal tooth structure remaining due to deep caries, resorption or traumatic injury. However, the technique has not been widely adopted, arguably because extraction of a severely compromised tooth may be difficult to achieve in a gentle and predictable way. In this paper, we present our novel approach to surgical extrusion and subsequent management of teeth using a vertical extraction system (Benex), which has become the method of choice in the authors' practice for many teeth that would otherwise be deemed unrestorable. We describe the clinical procedure in detail and discuss the advantages and disadvantages compared to alternative approaches, including surgical crown lengthening and orthodontic extrusion.

Guided Endodontics versus Conventional Access Cavity Preparation: A Comparative Study on Substance Loss Using 3-dimensional-printed Teeth.

INTRODUCTION: The aim of this in vitro study was to compare endodontic access cavities in teeth with calcified root canals prepared with the conventional technique and a guided endodontics approach regarding the detection of root canals, substance loss, and treatment duration. METHODS: Six identical sets of upper and lower jaw models were produced with 3-dimensional-printed incisors that had simulated calcified root canals. Splints for guided access preparations were fabricated based on 3-dimensional surface scans and cone-beam computed tomographic data sets. Under simulated clinical conditions, 3 operators with different levels of experience prepared access cavities on each front tooth with the conventional technique and guided endodontics (8 teeth per technique and operator). Access cavities were volumetrically assessed on postoperative cone-beam computed tomographic scans. Statistical significance was tested by examining the overlap of 95% confidence intervals (CIs). RESULTS: Canal location was successful in 10 of 24 cases (41.7%) using the conventional technique and 22 of 24 cases (91.7%) with the guided approach. The mean substance loss of the conventional access and the guided access was 49.9 mm3 (95% CI, 42.2-57.6 mm3) and 9.8 mm3 (95% CI, 6.8-12.9 mm3), respectively. The treatment lasted 21.8 minutes (95% CI, 15.9-27.7 minutes) for the conventional technique and 11.3 minutes (95% CI, 6.7-15.9 minutes) for guided endodontics. The success of the guided approach was not influenced by the experience of the operator. CONCLUSIONS: Guided endodontics allows a more predictable and expeditious location and negotiation of calcified root canals with significantly less substance loss.

When and how do endodontic specialists use cone-beam computed tomography?

This study investigated the use of cone-beam computed tomography (CBCT) by endodontists in Germany and Switzerland. Sixty-eight German endodontic specialists (G-ES), 22 Swiss endodontic specialists (CH-ES) and 95 dentists with a German Master of Science in endodontics (MSc) were invited to participate. Data on the timing of diagnostic assessments, endodontic case difficulty and indications for CBCT use were collected by questionnaire. The frequencies of pre-, intra- and postoperative use of periapical radiography and CBCT were analysed by case difficulty level. In high difficulty cases, access to a CBCT device was significantly associated with the frequency of both pre- and intraoperative CBCT use. The type of endodontic qualification had a significant impact on the rate of preoperative CBCT use in high difficulty cases. German endodontic specialists used preoperative CBCT more frequently than CH-ES and MSc. Our findings show that CBCT is a valuable imaging tool for endodontists, particularly in high difficulty cases.