Long-term survival of adhesively post-endodontically restored teeth

Randomized controlled trial comparing glass-fiber versus metal posts in single-crowned teeth: 15 Year follow-up

OBJECTIVE

This randomized controlled trial compared the 15-year clinical success and survival rate of endodontically treated teeth restored with glass-fiber or metal posts.

METHODS

131 patients in need of 182 post and single-crown restorations were included. Teeth were randomly assigned to the control group (metal post, Parapost XT, Coltène) or test group (glass-fiber post). Teeth in the test group were further divided based on the size and shape of the root canal (RC). Teeth with a small RC were restored with prefabricated glass-fiber posts (Parapost Fiberlux, Coltène) and teeth with a wide oval canal with custom-made glass-fiber posts (Everstick, StickTech). Patients had follow-up appointments at 3, 5 and 15 years. Success (original post present) and survival (present after intervention) probability lifetime curves, corrected for clustering, were calculated (Kaplan-Meier).

RESULTS

The mean follow-up time was 179.6 ± 7 months, and the recall rate was 91.6 %. Success rate was 48.0 % for metal posts, 59.2 % for prefabricated glass-fiber posts and 49.5 % for custom glass-fiber posts. Survival rate was 53.6 % for metal posts, 68.5 % for prefab glass-fiber posts and 55.3 % for custom glass-fiber posts. No statistically significant effect of post material was observed. There was, however, a trend towards better success/survival for teeth with prefabricated glass-fiber posts. Teeth with metal posts failed more frequently due to root fracture than teeth with glass-fiber posts.

CONCLUSIONS

There was a trend towards better clinical success and survival rate for teeth restored with glass-fiber posts, even though post material had no statistically significant effect on the clinical outcome.

CLINICAL SIGNIFICANCE

After 15-years, teeth restored with glass-fiber posts tended towards better clinical success and survival than teeth restored with gold-alloy posts. The difference in clinical outcome was, however, not statistically significant, probably due to a low effect size of the post material on success and survival.

Long-term success and survival of post-endodontic restorations without posts after up to 18 years: A practice-based study

OBJECTIVES

The aim of this non-interventional, multi-center, prospective, practice-based study was, firstly, to evaluate the longevity of composite build-ups in endodontically treated teeth, treated with root canal therapy (ETT), without post placement and secondly, to identify and analyze factors influencing the success of these reconstructions.

METHODS

Each of seven general dental practitioners placed up to 50 composite build-ups without additional posts in ETT. Teeth were restricted to incisors, canines and premolars. Clinical data (i.e. type of build-up restoration (material, adhesive); type of final restoration (material, adhesive)) were recorded for 192 coronal restorations on ETT in 192 patients. Cox proportional hazards models were applied to analyze associations between clinical factors and time until failure.

RESULTS

Within a follow-up period of up to 18 years (mean(95 %CI): 102 (90-113) months, max:217 months) 155 restorations (81 %) were judged as successful [mean success time: 176 (165-187) months] and 164 teeth (85 %) survived [mean survival time: 187 (178-197) months]. The main failure type was fracture of the restoration (n = 16). The annual failure rate was 2.4 % and 1.7 %, respectively. In bivariate Cox regression the factors 'dentist' and 'adhesive' were significantly associated with failure rate (p ≤ 0.017). However, in multivariate Cox proportional hazards regression none of the investigated factors were significantly associated with failure rate (p ≥ 0.089).

CONCLUSION

For composite build-ups in ETT without post placement high success rates could be found after up to 18 years of observation. Within the limitations of the present study none of the analyzed factors such as 'dentist' or 'adhesive was a significant predictor for the failure rate.

CLINICAL RELEVANCE

Endodontically treated teeth, treated with root canal therapy, can be successfully directly restored with composite build-ups even when no additional post is inserted. The study was registered in the German Clinical Trials Register (DRKS-ID: DRKS00012882).

Survival time and success rates of customized prefabricated metal posts: A retrospective study

STATEMENT OF PROBLEM

The choice of post type is still a controversial issue in dental practice. Furthermore, studies regarding the long-term survival and success of customized prefabricated posts are lacking.

PURPOSE

The purpose of this retrospective study was to assess the longevity of prefabricated metal posts customized to conform to the root canal.

MATERIAL AND METHODS

Data obtained from the records of patients who received a customized titanium or stainless-steel post at a private dental practice between July 1998 and March 2022 were analyzed. The prefabricated posts were customized by grinding the threads, reducing their length, and tapering them to fit into the existing canals. The relation between survival time and type of tooth and coronal restoration was searched. The Kaplan-Meier test was used for survival time and Cox regression to evaluate factors associated with survival (α=.05). The data were also analyzed for 5-year time intervals.

RESULTS

A total of 1791 posts in 1072 patients were available for the study. The mean overall survival time of the posts was 17.33 years. The mean survival time with regard to the coronal restoration was 15.22 years for direct composite resin restorations, 17.21 years for metal-ceramic crowns, 14.94 years for fixed partial dentures, and 12.63 years for removable partial dentures. The survival time for anterior teeth was 13.16 years and 17.53 years for posterior teeth. The success rate of the posts was 97.5%.

CONCLUSIONS

This retrospective study of customized prefabricated metal posts resulted in a 17-year post survival time and a success rate of 97.5%.

Influence of post material and ferrule thickness on the fracture resistance of endodontically treated premolars: A laboratory study

STATEMENT OF PROBLEM

The influence of the ferrule thickness and post materials on the fracture resistance of endodontically treated teeth remains unclear.

PURPOSE

The purpose of this laboratory study was to evaluate the influence of post material and ferrule thickness on the fracture resistance of endodontically treated mandibular premolars.

MATERIAL AND METHODS

Sixty-four extracted and endodontically treated mandibular first premolars were used and divided into 4 test groups (n=16) depending on the ferrule thickness: F-0: without a ferrule, F-0.5: with a 0.5-mm ferrule thickness, F-1: with a 1-mm ferrule thickness, and F-1.5: with a 1.5-mm ferrule thickness. In groups with ferrules, the height ranged from 2 mm buccally/lingually to 1 mm proximally. Teeth in subgroups (n=8) were restored with either prefabricated glass fiber (FF) or titanium posts (FT) (ISO size 70 and length of 7.5 mm) and then adhesively restored with composite resin foundation materials. After foundation procedures, each specimen was restored with a cobalt chromium crown which was cemented with glass ionomer cement. All specimens were subjected to dynamic loading in a masticatory simulator for 1 200 000 loading cycles with a nominal load of 5 Kg at 1.2 Hz and simultaneous thermocycling (5 to 55 °C). Specimens were then quasistatically loaded at 30 degrees in a universal testing machine until fracture. Fracture loads were analyzed by using 2-way ANOVA followed by the Tukey honestly significant difference test (α=.05).

RESULTS

Fracture loads ranged from 610 ±45 N (no ferrule - glass fiber post) to 1216 ±169 N (1.5 mm ferrule thickness - glass fiber post). A statistically significant increase in fracture resistance was observed with increasing ferrule thickness (P<.001). However, post materials did not show a statistically significant influence (P=.977).

CONCLUSIONS

Under the conditions of this laboratory study, increasing the ferrule thickness had a significant effect on the fracture resistance of endodontically treated teeth after thermomechanical fatigue, irrespective of post materials.

Clinical behavior and survival of endodontically treated teeth with or without post placement: a systematic review and meta-analysis

PURPOSE

Non-vital teeth usually exhibit substantial loss of coronal and radicular tooth structure, and use of posts after root canal treatment is controversial. This review examined whether placement of posts influences clinical behavior and survival probability of endodontically treated teeth (ETT).

METHODS

An electronic search, without time restrictions, for publications written in English was undertaken in PubMed, Scopus, and Web of Science. Terms related to four main components (endodontically treated teeth, fixed prosthesis, post restoration, and survival rate) were used for the database search strategies.

RESULTS

57 studies met the inclusion criteria and were included in the qualitative analysis. Of the publications chosen for qualitative analysis, 17 clinical studies (11 prospective and 6 retrospective studies) were found to be suitable for quantitative analysis. These studies included 7,278 patients (7,330 ETT), with a mean age ± standard deviation (SD) of 45.46 ± 12.1 years. There was a statistically significant difference in survival rate between ETT with or without posts (P < 0.001).

CONCLUSION

As compared with teeth with no posts, post placement on ETT may improve clinical performance and survival probability of endodontically treated teeth.

Restoration of teeth lacking complete ferrules using cast precious metal alloy post-and-cores and knife-edged crowns: A retrospective clinical study

STATEMENT OF PROBLEM

While the presence of a ferrule has been reported to be essential for post-and-core restorations, many extensively damaged teeth lack complete ferrules. The outcome of post-and-core restorations for these teeth remains uncertain.

PURPOSE

The purpose of this retrospective clinical study was to assess the outcome of cast alloy post-and-cores and knife-edged crowns for the restoration of teeth lacking complete ferrules.

MATERIAL AND METHODS

A total of 106 participants with endodontically treated teeth with 2 or fewer walls with ferrules who had received cast precious metal alloy post-and-cores along with knife-edged crowns between 2013 and 2022 were recalled for a clinical examination. The minimum follow-up time was 5 months after restoration, and restoration failure and the periodontal status difference between restored teeth and reference teeth were determined. Kaplan-Meier analysis was performed to obtain success curves. The influence of age, sex, jaw position, tooth type, and antagonistic dentition upon the success function was analyzed with the log-rank or Breslow test (α=.05).

RESULTS

A total of 100 participants with 130 restorations were studied. The success rate of the restorations was 93.85% in a mean ±standard deviation period of 48.3 ±26.1 months. The estimated 5-year cumulative success probability was 91.61%. No significant effect on the success of restorations was found regarding age, sex, jaw position, tooth type, or antagonistic dentition (P>.05). The main failure types were post debonding, root fracture, and apical periodontitis. No statistical difference in tooth mobility (Z=-1.265, P=.206) was found between the restored and the reference teeth, but the plaque index and calculus index of the restored teeth were significantly lower than of the reference teeth (Z=-7.216, P<.001; Z=-7.044, P<.001). Teeth that had received cast post-and-cores and knife-edged crowns were found to have no significant correlation with periodontal disease (χ²=1.131, P=.288) or bleeding on probing (χ²=3.436, P=.064).

CONCLUSIONS

The clinical outcomes for the restoration of teeth with 2 or fewer walls with ferrules using cast precious metal alloy post-and-cores and knife-edged crowns were favorable, exhibiting a high 5-year cumulative success probability and no increased periodontal health risk.

Understanding the Complexities of Cast Post Retention: A Comprehensive Review of Influential Factors

This comprehensive review delves into the intricate landscape of cast post retention in restorative dentistry, encompassing historical perspectives, contemporary techniques, and future directions. Examining factors ranging from tooth-related considerations to prosthesis-related dynamics, the review provides a detailed analysis of clinical techniques, including step-by-step procedures, common challenges, and innovative advancements. Technological breakthroughs, such as digital impressions, computer-aided design and computer-aided manufacturing (CAD/CAM) technology, three-dimensional (3D) printing, and finite element analysis, are explored for their transformative impact on precision and customization. The discussion extends to the promising future of cast post retention, emphasising emerging materials, the integration of artificial intelligence in treatment planning, and patient-specific approaches. Implications for clinical practice underscore the importance of individualised treatment planning and the adoption of advanced technologies. Recommendations for future research advocate for comprehensive long-term clinical studies, investigations into AI-driven treatment planning, and a focus on patient outcomes and satisfaction. This review consolidates existing knowledge and anticipates a future marked by enhanced precision, individualised care, and improved long-term success in cast post-retained restorations.

Survival of severely compromised endodontically treated teeth restored with or without a fiber glass post

OBJECTIVE

The use of a fiber glass post (FGP) type and choice of FGP diameter to restore endodontically treated incisors without ferrule is controversial. This study evaluated survival rate and failure mode of severely compromised central incisors without ferrule rehabilitated using resin-based composite (RBC) with or without FGP with different diameters.

METHODOLOGY

A total of 60 decoronated bovine incisors without a ferrule were endodontically treated and prepared for 1.4, 1.6, and 1.8 mm diameter FGPs (Whitepost System DC 0.5, Fit 0.4, and DCE 0.5; FGM). Half of the teeth received FGPs cemented using dual-cure resin cement (Allcem Core; FGM), the other half were filled using only bulk-fill RBC (OPUS Bulk Fill; FGM). The crowns were directly restored with RBC. The roots were embedded in polystyrene resin and the periodontal ligament was simulated with polyether impression material. Fatigue testing was conducted under 5 Hz cyclic loading at 30 degrees to the incisal edge, beginning at 50 N (5,000 cycles) as a warmup. After, the load was increased 100 N every 15,000 cycles until fracture occurred. All specimens were subjected to transillumination, micro-CT analysis, and digital radiography before and after fatigue testing. Fracture mode was classified according to severity and repair potential. Data were analyzed with Kaplan-Meier survival test and post hoc log-rank test (α=0.05) for pairwise comparisons.

RESULTS

Using FGP significantly increased the number of cycles to failure, irrespective of FGP diameters (p=0.001). The FGP diameters had no statistically significant effect on cycles to failure or failure mode.

CONCLUSION

Using FGP without ferrule improved survival rate of structurally severely compromised central incisors compared with rehabilitation without FGP. The diameter of the FGPs had no effect on the survival rate and failure mode.

Health economic evaluation of forced orthodontic extrusion of extensively damaged teeth: up to 6-year results from a clinical study

OBJECTIVES

Clinical data on retaining extensively damaged teeth using forced orthodontic extrusion followed by restorative rehabilitation are scarce, and economic evaluations are basically absent. A health economic evaluation of this method was performed based on a clinical study.

MATERIALS AND METHODS

In a convenience sample of individuals recruited from routine care, extensively damaged teeth were orthodontically extruded prior to restoration. Patients were followed up for up to 6 years. The health outcome was tooth retention time. Direct medical, non-medical, and indirect initial and follow-up costs were estimated using the private payer's perspective in German healthcare. Association of initial direct medical treatment costs and cofounding variables was analyzed using generalized linear models. Success and survival were secondary outcomes.

RESULTS

A total of 35 teeth in 30 patients were followed over a mean ± SD of 49 ± 19 months. Five patients (14%) dropped out during that period. Median initial costs were 1941€ (range: 1284-4392€), median costs for follow-up appointments were 215€ (range: 0-5812€), and median total costs were 2284€ (range: 1453 to 7109€). Endodontic re-treatment and placement of a post had a significant impact on total costs. Three teeth had to be extracted and in three patients orthodontic relapse was observed. The survival and success rates were 91% and 83%, respectively.

CONCLUSIONS

Within the limitations of this clinical study, total treatment costs for orthodontic extrusion and subsequent restoration of extensively damaged teeth were considerable. Costs were by large generated initially; endodontic and post-endodontic therapies were main drivers. Costs for retreatments due to complications were limited, as only few complications arose.

CLINICAL RELEVANCE

The restoration of extensively damaged teeth after forced orthodontic extrusion comes with considerable initial treatment costs, but low follow-up costs. Overall and over the observational period and within German healthcare, costs are below those for tooth replacement using implant-supported crowns.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: DRK S00026697).

Vertical root fracture resistance and crack formation of root canal-treated teeth restored with different post-luting systems

The aim was to investigate the vertical root fracture (VRF) resistance and crack formation of root canal-treated teeth restored with different post-luting systems. Human maxillary lateral incisors of similar size were decoronated, assigned to five groups (n = 18, power = 0.9) and embedded in acrylic blocks with artificial periodontal ligament. After root canal filling, post spaces were prepared to place coated fiber-reinforced composite (FRC) or sandblasted titanium (Ti) posts of the same shape and size. Half of the posts were zinc phosphate cemented (C), while the other half was adhesively luted (A). Untreated teeth served as control. After thermal cycling and staircase loading in a chewing simulator, the crack formation on the root dentin surface was microscopically examined and classified as no defect, craze line, vertical crack, and horizontal crack. Subsequently, the samples were loaded until root fracture. Data were analyzed by one-way ANOVA, Tukey’s test, and Fisher’s exact test. All samples survived the chewing simulation without VRF, but crack formation was significantly different between the groups (P = 0.009). The control showed significantly fewer defects than FRC/C, Ti/C, and Ti/A (P = 0.001, P = 0.008, P = 0.008, respectively). FRC/C showed the highest incidence of vertical cracks. FRC/A had the lowest incidence of defects. There was no significant difference in VRF resistance between the groups (P = 0.265). Adhesively luted FRC posts did not increase VRF resistance but reduced the risk of defects. Most defects were craze lines and vertical root cracks.