Strategic considerations in treatment planning: deciding when to treat, extract, or replace a questionable tooth

LONG-TERM OUTCOMES OF IMPLANT PLACEMENT VERSUS TOOTH PRESERVATION IN PERIODONTALLY COMPROMISED TEETH MAY BE COMPARABLE

ARTICLE TITLE AND BIBLIOGRAPHIC INFORMATION

Sarafidou K, Lazaridi I, Gotsis S, Kirmanidou Y, Vasilaki D, Hirayama H, Michalakis K. Tooth preservation vs. extraction and implant placement in periodontally compromised patients: A systematic review and analysis of studies. J Prosthodont. 2022 Oct;31(8):e87-e99. doi:10.1111/jopr.13560. Epub 2022 Aug 2. PMID: 35794083 SOURCE OF FUNDING: No external funding was received for this research.

TYPE OF STUDY/DESIGN

Systematic review (without meta-analysis).

A biologically oriented preparation technique (BOPT) for immediate posterior implant placement, immediate provisionalization, and definitive implant crown fabrication: A complete digital workflow

OBJECTIVE

Immediate implants and immediate alveolar sealing have been a widely utilized treatment with high predictability and biological advantages. The improvement in technology has made it possible to simplify clinical processes. The aim of the present report was to describe the complete digital workflow of the Biologically oriented preparation technique for immediate posterior implant, immediate provisionalization and fabrication of definitive implant crowns.

CLINICAL CONSIDERATIONS

The surgical process and prosthetic management to preserve the gingival contours of the extracted natural tooth during immediate implant placement and provisionalization are described. Additionally, during the same clinical intervention, the definitive intraoral digital implant scans for capturing the implant position, peri-implant tissue contours, adjacent and antagonist dentition, and profile emergence of the interim implant crown are captured for the fabrication of the definitive crown.

CONCLUSIONS

Based on the technique described, the immediate implant placement and provisionalization in the posterior area provides biological and clinical advantages, reducing the number of abutment-implant disconnections and the number of clinical appointments, as well as increases patient comfort.

CLINICAL SIGNIFICANCE

The present article describes a technique for an immediate implant placement and provisionalization in the posterior region for maintaining the gingival architecture of the extracted tooth. During the same appointment, the implant position, peri-implant tissue contours, and adjacent and antagonist dentition, and profile emergence of the interim implant crown are captured by using an intraoral scanner and used for the fabrication of the definitive crown. This technique aims to reduce the number of abutment-implant disconnections and clinical appointments.

Translating the determinant aspects on the study design in the dental implant field

Objective

In this article, we analyzed the important categories capable of interfering with the determinants of scientific advancement in the type of study, considering seven leading journals over a 20-year.

Methodology

A bibliometric review was performed at the website of well-established implant dentistry journals in five-time points defined to represent a 20-year period of observation. The measures associated with the type of study design were: the country of origin of the article, country income, continent of the corresponding author, inter-institutional collaboration, interdisciplinary collaboration, type of funding, and topic of research. Logistic regression was used in the multiple models to identify the exploratory factors associated with the type of study.

Results

From a total of 1,944 articles, 50.6% comprised clinical studies. High-income countries and continents stood out for developing more clinical research than others. Since research funders request more collaborative research, overall clinical studies depended upon more inter-institutional collaboration than the others. Most clinical studies were partly supported by research institutes or universities and by industry. About the research topic, the majority of the clinical and animal studies disclosed surgical procedures.

Conclusions

High-income countries and continents are more likely to develop clinical studies in the surgical procedures field. The highest collaborations in terms of the number of institutions and funding sources are more prevalent in clinical research designs. Indeed, most in vivo studies in dental implant fields are performed to evaluate new materials or even new surgical procedures.

Success and complication rates of non-precious alloy telescopic crowns in a general dental practice

OBJECTIVES

This retrospective, single-center, practice-based cohort study aimed to analyze factors associated with the success of removable partial dentures retained by telescopic crowns (TRPD).

MATERIALS AND METHODS

TRPD which were placed in a single practice of a practice-based research network were analyzed. Data from 139 patients (age (SD): 66 (11) years; 66 female) with 174 TRPD including 488 non-precious alloy telescopic crowns (TC) between 2004 and 2016 were included. TC without any technical complication were considered as successful, and as survived, if they were still in function at the last check-up. Multilevel Cox proportional hazard models were used to evaluate the association between clinical factors and time until failure.

RESULTS

Within a mean follow-up period (SD) of 4.2 (3.3) years (min-max: 1 day-12 years), 372 (76%) TC (AFR5years,TC-level: 5.0%) as well as 136 (87%) TRPD (AFR5years,TRPD-level: 5.1%) ("worst-case scenario") and 150 (86%) TRPD (AFR5years,TRPD-level: 3.4%) ("best-case scenario") were considered as successful. The main failure types were recementation (n = 39), endodontic treatment (n = 36), and extraction (n = 35). TC in male patients showed 1.6 times higher risk for failure than in female patients (95%CI: 1.1-2.4; p = 0.023). TC on premolars showed 2.2 times higher risk for failure than on incisors (95%CI: 1.1-5.0; p = 0.023) and TC in dentures with ≤ 3TC showed 2.1 times higher risk for failure than TC in dentures with > 3TC (1.3-3.4; p = 0.042). Furthermore, TC on the most distal tooth in an arch showed 2.4 times higher risk for failure than TC on a more mesial tooth (1.5-3.8; p < 0.001).

CONCLUSION

For removable partial dentures retained by telescopic crowns, high success rates could be found after up to 12 years. Patient-level and tooth-level factors were significantly associated with failure.

CLINICAL RELEVANCE

For removable partial dentures retained by telescopic crowns, high success rates could be found after up to 12 years. Patient-level and tooth-level factors were significantly associated with failure.

Effect of mandibular bilateral distal extension denture design on masticatory performance

PURPOSE

Removable partial dentures have a wide range of applications as missing tooth prostheses, and the denture design can be quite diverse. However, the factors affecting masticatory function remain unclear. We investigated the effect of denture design, especially the use of indirect retainers and major connectors, on masticatory function in patients with mandibular bilateral distal extension dentures.

METHODS

Fifty-three patients with mandibular Kennedy Class I and Eichner classification B occlusal support were included in this study. Masticatory performance (MP) was assessed using gummy jelly. For the dentures, the type of major connector (bar or apron), presence or absence of indirect retainers, number of rests, and number of artificial teeth were evaluated. The number of functional teeth and occlusal support, Eichner classification, maxillary denture usage, mandibular residual ridge height, and duration of denture use were also evaluated. The factors influencing on the MP were evaluated using the Mann-Whitney U test, Spearman's correlation coefficient, and logistic regression analysis.

RESULTS

MP was significantly higher when the major connector was bar-type or when there was an indirect retainer than with an apron-type or no indirect retainer. MP was positively correlated with the number of functional teeth, occlusal support, and number of rests. Logistic regression analysis revealed that the number of functional teeth and the presence or absence of an indirect retainer were factors that significantly influenced the MP.

CONCLUSIONS

An indirect retainer setting is useful for achieving good masticatory performance in mandibular bilateral distal extension dentures.

Forced surgical extrusion using an axial tooth extraction system as a practicable technique for preserving severely destroyed teeth? - Clinical outcomes up to 4.8 years

OBJECTIVE

Several extrusion techniques have been described to restore teeth with insufficient coronal tooth structure and to avoid their extraction. Still, there is little evidence for a treatment concept combining surgical extrusion using an atraumatic axial extraction system.

MATERIALS AND METHODS

A total of nine patients, each with an iso- or subgingival fractured tooth, were retrospectively examined. Treatment of the damaged tooth comprised an atraumatic forced surgical extrusion performed with an axial tooth extraction system and a more coronal positioning within the socket. The teeth were initially splinted and subsequently restored. The follow-up period was up to 57.1 months and averaged 36.5 (SD: ±13.5) months.

RESULTS

All nine teeth were still in situ, without signs of inflammation. During the period of the provisional restoration, six prosthetic complications occurred, which were resolved with little effort, whereas, success rate for the definitive restoration was 100%. No biological complications were observed concerning the root apex or soft tissue. The radiographically measured mean extrusion distance was 3.4 (SD: ±1.0) mm, so that a sufficient prosthetic ferrule could be reestablished.

CONCLUSIONS

Surgical extrusions using an axial tooth extraction system demonstrate low biological and prosthetic complications rates over observation time.

CLINICAL SIGNIFICANCE

The presented extrusion approach preserves soft and hard tissue and is an efficient treatment option for severely destroyed teeth. Saving hopeless teeth by this relatively predictable and feasible procedure has hardly any disadvantages for patients, and in case of failure, an implant or fixed partial denture are still an option.

Radiographic predictive factors for 10-year survival of removable partial denture abutment teeth: Alveolar bone level and density

PURPOSE

To determine postoperative periodontal and radiographic factors that predict the survival rates of abutments of removable partial dentures (RPDs).

METHODS

Patients who wore RPDs for > 10 years and received supportive periodontal therapy were included. Periodontal examinations and radiographic assessments were conducted on 83 abutment teeth in 35 patients at baseline, and five years after RPD insertion. In addition to conventional factors, such as tooth mobility at 5 years, radiographic factors, such as the crown-root ratio (ΔCR ratio) and gray-level changes reflecting changes in alveolar bone density (ΔABD), were evaluated. The impact of the covariables on the 10-year survival of abutment teeth was estimated using a multivariate Cox regression model, considering multicollinearity.

RESULTS

Patients were classified as having A2-B2 (45.7%) and B3-C2 (54.3%) tooth loss, according to the Eichner classification. A probing depth ≥ 4 mm, tooth mobility ≥ grade 1, and CR ratio ≥ 1 were found in 30.1%, 33.7%, and 51.8% of abutment teeth, respectively. The 10-year survival rate of abutment teeth was 86.7%. Multivariate analysis showed that the 10-year survival of abutment teeth was significantly associated with root canal treatment (P = 0.045, hazard ratio [HR] = 1.23), the 5-year ΔCR ratio (P = 0.022, HR = 3.20), and ΔABD on the edentulous side of the abutment teeth (P = 0.047, HR = 1.08).

CONCLUSIONS

In addition to root canal treatment, changes in the CR ratio and radiographic alveolar bone density at five years predicted the long-term survival rate of RPD abutments.

Clinical decision making of post-treatment disease

Root-filled teeth presenting with signs of post-treatment disease is a common finding in virtually every dental practice. There is both empirical and experimental evidence that, as long as the condition is asymptomatic, it is often left untreated. Professional judgements and decision making in endodontics as in any medical discipline are based on qualified estimations of the probability and the value of relevant outcomes. In this paper we describe various aspects of clinical decision making in general, from a descriptive as well as a normative point of view, but with a particular focus on the condition of the root-filled tooth with post-treatment disease. We review how attention to various types of uncertainties are relevant for the decision-making process. Additionally, we discuss the nature of value judgements and different concepts of health and disease which are important for understanding the complexity of the clinical decision-making process. We also refer to a set of principal rules that can guide the clinician's decision making in every-day practice in front of a case with endodontic post-treatment disease. Finally, we provide some aspects on the sometime cumbersome decision whether to go for a non-surgical or surgical method, whenever a decision on retreatment has been made.

Oral and Periodontal Risk Factors of Prosthetic Success for 3-Unit Natural Tooth-Supported Bridges versus Implant-Supported Fixed Dental Prostheses

The goals of this research are: (1) to compare the survival and prosthetic success of metal-ceramic 3-unit tooth- versus implant-supported fixed dental prostheses; (2) to evaluate the influence of several risk factors on the prosthetic success of tooth- and implant-supported fixed dental prostheses (FPDs). A total of 68 patients with posterior short edentulous spaces (mean age 61.00 ± 1.325 years), were divided into two groups: 3-unit tooth-supported FPDs (40 patients; 52 FPD; mean follow-up 10.27 ± 0.496 years) and 3-unit implant-supported FPDs (28 patients; 32 FPD; mean follow-up 8.656 ± 0.718 years). Pearson-chi tests were used to highlight the risk factors for the prosthetic success of tooth- and implant-supported FPDs and multivariate analysis was used to determine significant risk predictors for the prosthetic success of the tooth-supported FPDs. The survival rates of 3-unit tooth- versus implant-supported FPDs were 100% and 87.5%, respectively, while the prosthetic success was 69.25% and 68.75%, respectively. The prosthetic success of tooth-supported FPDs was significantly higher for patients older than 60 years (83.3%) vs. 40-60 years old (57.1%) (p = 0.041). Periodontal disease history decreased the prosthetic success of tooth- versus implant-supported FPDs when compared with the absence of periodontal history (45.5% vs. 86.7%, p = 0.001; 33.3% vs. 90%, p = 0.002). The prosthetic success of 3-unit tooth- vs. implant-supported FPDs was not significantly influenced by gender, location, smoking, or oral hygiene in our study. In conclusion, similar rates of prosthetic success were recorded for both types of FPDs. In our study, prosthetic success of tooth- versus implant-supported FPDs was not significantly influenced by gender, location, smoking, or oral hygiene; however, history of periodontal disease is a significant negative predictor of success in both groups when compared with patients without periodontal history.

Mechanical, Chemical, and Biological Properties of 3D-Printed Abutments: A Systematic Review

Aim:

A systematic review of the methods of 3D printing and the materials used so far for the manufacture of abutments was performed to evaluate whether their clinical use is indicated through the mechanical, chemical, and biological analyses carried out.

Materials and Methods:

An electronic search conducted by three independent reviewers was carried out in the PubMed, Web of Science, Cochrane Library, Science Direct, and Lilac databases. The inclusion criterion was researching articles in English that contained as subject the manufacturing of abutments through 3D printing/additive manufacturing. Any meta-analyses, reviews, book chapters, abstracts, letters, conferences papers, and studies without abutments printed were excluded.

Results:

We found 780 references, which after applying the exclusion criteria resulted in the final inclusion of seven articles for review. The studies had a high heterogeneity, showing different materials and methodologies to manufacture abutments, which makes a comparison between them difficult, and for this reason it was not possible to carry out a meta-analysis with the data found.

Conclusions:

Even with the limitations found in the present research, it is possible to conclude that printed abutments have adequate mechanical, chemical, and biological properties that can indicate their clinical use. 3D printing presents high accuracy and speed and can produce customized abutments according to each case.

Personalized workflows in reconstructive dentistry-current possibilities and future opportunities

Objectives

The increasing collection of health data coupled with continuous IT advances have enabled precision medicine with personalized workflows. Traditionally, dentistry has lagged behind general medicine in the integration of new technologies: So what is the status quo of precision dentistry? The primary focus of this review is to provide a current overview of personalized workflows in the discipline of reconstructive dentistry (prosthodontics) and to highlight the disruptive potential of novel technologies for dentistry; the possible impact on society is also critically discussed.

Material and methods

Narrative literature review.

Results

Narrative literature review.

Conclusions

In the near future, artificial intelligence (AI) will increase diagnostic accuracy, simplify treatment planning, and thus contribute to the development of personalized reconstructive workflows by analyzing e-health data to promote decision-making on an individual patient basis. Dental education will also benefit from AI systems for personalized curricula considering the individual students’ skills. Augmented reality (AR) will facilitate communication with patients and improve clinical workflows through the use of visually guided protocols. Tele-dentistry will enable opportunities for remote contact among dental professionals and facilitate remote patient consultations and post-treatment follow-up using digital devices. Finally, a personalized digital dental passport encoded using blockchain technology could enable prosthetic rehabilitation using 3D-printed dental biomaterials.

Clinical significance

Overall, AI can be seen as the door-opener and driving force for the evolution from evidence-based prosthodontics to personalized reconstructive dentistry encompassing a synoptic approach with prosthetic and implant workflows. Nevertheless, ethical concerns need to be solved and international guidelines for data management and computing power must be established prior to a widespread routine implementation.

Treatment approaches and outcome trajectories for youth with high-risk opioid use: A narrative review

AIM

First use of opioids often happens in adolescence and an increasing number of opioid overdoses are being reported among youth. The purpose of this narrative review was to present the treatment approaches for youth with high-risk opioid use, determine whether the literature supports the use of opioid agonist treatment among youth and identify evidence for better treatment outcomes in the younger population.

METHODS

A search of the literature on PubMed using MeSH terms specific to youth, opioid use and treatment approaches generated 1436 references. Following a screening process, 137 papers were found to be relevant to the treatment of high-risk opioid use among youth. After full-text review, 19 eligible studies were included: four randomized controlled trials, nine observational studies and six reviews.

RESULTS

Research for the different treatment options among youth is limited. The available evidence shows better outcomes in terms of retention in care and cost-effectiveness for opioid agonist treatment than abstinence-based comparisons. Integrating psychosocial interventions into the continuum of care for youth can be an effective way of addressing comorbid psychiatric conditions and emotional drivers of substance use, leading to improved treatment trajectories.

CONCLUSIONS

From the limited findings, there is no evidence to deny youth with high-risk opioid use the same treatment options available to adults. A combination of pharmacological and youth-specific psychosocial interventions is required to maximize retention and survival. There is an urgent need for more research to inform clinical strategies toward appropriate treatment goals for such vulnerable individuals.

[Recommendation of tooth extraction and associated factors: cross-sectional study in the Kiriri indigenous population]

The scope of this cross-sectional study was to evaluate the prevalence and the associated factors of the recommendation of dental extraction in the adult Kiriri Indigenous population of northeastern Brazil. A total of 225 natives (≥19 years) were evaluated. The extraction criteria were teeth with clinical attachment loss ≥50% in at least 3 sites, and residual roots. Statistical models were used to evaluate associations between the need for dental extraction and selected variables. The percentage of teeth recommended for dental extraction was 4.98%, characterizing a mean of 1.24 tooth per individual. A regression analysis showed that age ≥35 years (OR=2.24, 95%CI: 1.13-4.43, p=0.02), income <R$ 570.00 (OR=3.34, 95%CI: 1.19-9.37, p=0.02) and plaque index ≥40% (OR=2.38, 95%CI: 1.24-4.56, p=0,01) were significantly associated with indication for dental extraction. A prevalence of 33% of subjects with dental extraction recommendation were associated with age older than 35 years, plaque index ≥40% and income less than a minimum wage were related with the recommendation for extraction. This study reflects the importance of prioritizing oral health prevention, as well as the need to expand complex dental services.

The Use and Performance of Artificial Intelligence in Prosthodontics: A Systematic Review

(1) Background: The rapid pace of digital development in everyday life is also reflected in dentistry, including the emergence of the first systems based on artificial intelligence (AI). This systematic review focused on the recent scientific literature and provides an overview of the application of AI in the dental discipline of prosthodontics. (2) Method: According to a modified PICO-strategy, an electronic (MEDLINE, EMBASE, CENTRAL) and manual search up to 30 June 2021 was carried out for the literature published in the last five years reporting the use of AI in the field of prosthodontics. (3) Results: 560 titles were screened, of which 30 abstracts and 16 full texts were selected for further review. Seven studies met the inclusion criteria and were analyzed. Most of the identified studies reported the training and application of an AI system (n = 6) or explored the function of an intrinsic AI system in a CAD software (n = 1). (4) Conclusions: While the number of included studies reporting the use of AI was relatively low, the summary of the obtained findings by the included studies represents the latest AI developments in prosthodontics demonstrating its application for automated diagnostics, as a predictive measure, and as a classification or identification tool. In the future, AI technologies will likely be used for collecting, processing, and organizing patient-related datasets to provide patient-centered, individualized dental treatment.

Expected Costs of Primary Dental Treatments and Endoscopic Sinus Surgery for Odontogenic Sinusitis

OBJECTIVES

Treatment of odontogenic sinusitis (ODS) due to apical periodontitis (AP) is highly successful when both dental treatment and endoscopic sinus surgery (ESS) are performed. Variation exists in the literature with regard to types and timing of dental treatments and ESS when managing ODS. This study modeled expected costs of different primary dental and sinus surgical treatment pathways for ODS due to AP.

STUDY DESIGN

Decision-tree economic model.

METHODS

Decision-tree models were created based on cost and treatment success probabilities. Using Medicare and consumer online databases, cost data were obtained for the following dental and sinus surgical treatments across the United States: root canal therapy (RCTx), revision RCTx, apicoectomy, extraction, dental implant, bone graft, and ESS (maxillary, ± anterior ethmoid, ± frontal). A literature review was performed to determine probabilities of dental and sinus disease resolution after different dental treatments. Expected costs were determined for primary dental extraction, RCTx, and ESS pathways, and sensitivity analyses were performed.

RESULTS

Expected costs for the three different primary treatment pathways when dental care was in-network and all diseased sinuses opened during ESS were as follows: dental extraction ($4,753.83), RCTx ($4,677.34), and ESS ($7,319.85).

CONCLUSIONS

ODS due to AP can be successfully treated with primary dental treatments, but ESS is still frequently required. Expected costs of primary dental extraction and RCTx were roughly equal. Primary ESS had a higher expected cost, but may still be preferred in patients with prominent sinonasal symptoms. Patients' insurance coverage may also impact decision-making.

LEVEL OF EVIDENCE

N/A Laryngoscope, 2021.

Minimally Invasive Periodontology: A Treatment Philosophy and Suggested Approach

Severe periodontitis is a highly prevalent dental disease. With the advent of implant dentistry, teeth are often extracted and replaced. Periodontal surgery, where indicated, could also result in increased trauma to the patient. This literature review discusses different treatment modalities for periodontitis and proposes a treatment approach emphasizing maximum preservation of teeth while minimizing morbidity to the patient. Scientific articles were retrieved from the MEDLINE/PubMed database up to January 2021 to identify appropriate articles that addressed the objectives of this review. This was supplemented with hand searching using reference lists from relevant articles. As tooth prognostication does not have a high predictive value, a more conservative approach in extracting teeth should be abided by. This may involve repeated rounds of nonsurgical periodontal therapy, and adjuncts such as locally delivered statin gels and subantimicrobial-dose doxycycline appear to be effective. Periodontal surgery should not be carried out at an early phase in therapy as improvements in nonsurgical therapy may be observed up to 12 months from initial treatment. Periodontal surgery, where indicated, should also be minimally invasive, with periodontal regeneration being shown to be effective over 20 years of follow-up. Biomarkers provide an opportunity for early detection of disease activity and personalised treatment. Quality of life is proposed as an alternative end point to the traditional biomedical paradigm focused on the disease state and clinical outcomes. In summary, minimally invasive therapy aims to preserve health and function of the natural dentition, thus improving the quality of life for patients with periodontitis.

The Effect of Patient Specific Factors on Occlusal Forces Generated: Best Evidence Consensus Statement

PURPOSE

The purpose of this Best Evidence Consensus Statement was to search the literature to determine if there is a relationship between patient specific factors and occlusal force.

MATERIALS AND METHODS

A literature review was conducted in the following databases: Evidence-Based Medicine Reviews (EBMR), Cochrane Database of Systematic Reviews, Embase, and Ovid MEDLINE(R) and Epub Ahead of Print. Articles on patient factors and occlusal force were compiled by using a combination of the key words: "bite force," "occlusal force," "partial and complete edentulism," "bruxism," and "orthognathic class." Inclusion criteria included meta-analyses, systematic reviews, randomized controlled trials, case series, and journal articles. Exclusion criteria were case reports, studies in children, animals, and bench studies.

RESULTS

Of the 1502 articles that met the initial search criteria, 97 related to patient-specific factors affecting occlusal forces. These articles were evaluated, rated, and organized into appropriate categories addressing questions of foci.

CONCLUSIONS

The range of occlusal force is highly variable among subjects correlated to patient specific factors such as age, gender, partial and complete edentulism, the presence of a maxillofacial defect, location of edentulous area, orthognathic profile, and magnitude of occlusal vertical dimension. Tooth replacement therapies targeted at increasing occlusal contact seem to have a positive effect on increasing occlusal force. Bruxism does not necessarily demonstrate higher occlusal powering but may have greater tooth contact time. Occlusal force is not clearly affected by the type of dental restoration or restorative material used. The clinical significance of the changes in occlusal forces is yet to be determined.

Effect of fatigue loading and failure mode of different ceramic implant abutments

STATEMENT OF PROBLEM

Currently many options are available for restoring a dental implant, although the ideal implant abutment for withstanding the occlusal load and the restorative material for fulfilling the esthetic need remains unclear. Zirconia (Zir) abutments offer good esthetics, but concerns still remain regarding their fracture strength, complex fabrication, and higher cost as compared with those of titanium (Ti) base abutments offering lower cost, acceptable esthetics, and a straightforward procedure.

PURPOSE

The purpose of this in vitro study was to evaluate the fracture strength and failure mode of single-tooth Zir and Ti base implant abutments with fatigue loading.

MATERIAL AND METHODS

Forty restorations were included using 4 different types of abutment-restorations. Zir abutments with lithium disilicate crowns (ZirLd); titanium base abutments with custom Zir abutments and lithium disilicate crowns (TiZirLd); titanium base abutments with monolithic lithium disilicate abutment-crowns (TiLd); titanium base abutments with monolithic polymer-infiltrated ceramic abutment-crowns (TiEn). Specimens were subjected to a progressive cyclic loading by using a custom-made mastication simulator at a frequency of 1.4 Hz starting with a load of 88 N followed by stages of 170, 210, 250, and 290 N for a maximum of 20 000 cycles each or until fracture occurred. The number of cycles, maximum load, and failure modes were recorded. Statistical analysis was done by using the Mann-Whitney U test (α=.05).

RESULTS

Group TiEn showed a lower resistance to fatigue, with a mean ±standard deviation of 5054 ±123.3 cycles subjected to a mean force of 170 N. Groups ZirLd and TiLd resisted higher forces without fracture 13452.6 ±7094.3 cycles, and load of 178 ±16.9 N, followed by the TiLd group with a mean ±standard deviation of 25798.6 ±5498.7 cycles, and load of 202 ±16.9 N, while the TiZirLd group showed a mean of 48235.4 cycles subjected to a mean force of 258 N. The failure mode observed in the TiEn occurred only in the ceramic, whereas in the ZirLd and TiLd group, it was above the shoulder level of the Ti base abutment. Even though the TiZirLd group was able to withstand higher loads and a higher number of cycles, the failures were catastrophic and presented fractures of the titanium-base abutment and prosthetic screw.

CONCLUSIONS

The TiZirLd, ZirLd, and TiLd abutment-restorations have the potential to withstand the average physiological occlusal forces that occur in the anterior region. The group with the higher fatigue resistance was TiZirLd, although care should be taken with patients presenting parafunctional habits since the failure mode can be catastrophic. Also, polymer-infiltrated ceramic is not suitable for a Ti base abutment when subjected to oblique loading.

Magnetic extrusion technique for restoring severely compromised teeth: A case report

An orthodontic magnetic extrusion technique is described for the management of an extensively damaged maxillary premolar. A cylindrical neodymium-iron-boron (Nd₂Fe₁₄B) magnet was attached to the remaining tooth structure, and a second magnet was placed on a resin-bonded partial denture. A 4.5-mm extrusion was obtained after 3 adjustments, and the tooth was prepared with a 3-mm buccal and 2-mm lingual ferrule by following a biologically oriented preparation technique and restored with a monolithic zirconia crown. Eighteen months after completing the treatment, no evidence of soft tissue dehiscence, abnormal tooth mobility, endodontic failure, or root resorption was found.

Single crowns on tooth root-resected molars: A retrospective multicentric study

STATEMENT OF PROBLEM

Data regarding single restorations on molars treated with root resection and separation are limited.

PURPOSE

The purpose of this retrospective study was to evaluate the clinical success and survival of single crowns on root-resected molars.

MATERIAL AND METHODS

Eighty-six molars were treated with root resection or hemisection, prepared with feather-edge margins and restored with single crowns in 73 patients. The patients were clinically evaluated during regular recall appointments in 2018. Data were analyzed with descriptive statistics.

RESULTS

The mean follow-up time was 88.7 months (standard deviation, 70.6; range, 6 to 284). Six failures were recorded during the observation period, with a cumulative survival rate of 93%.

CONCLUSIONS

In this retrospective evaluation, single crowns on root-resected molars with feather-edge margins had clinical outcomes similar to those reported for single crowns on implants in the molar area. First molars and molars with 2 retained roots showed a better survival rate than second molars.

Extractions in Patients with Periodontal Diseases and Clinical Decision-Making Process

Objectives

To investigate the professional aspects and clinical and radiographic evidence that influences the decision for the extraction of teeth among periodontologists and general dentists.

Material and methods

The sample consisted of 150 (n=106 females and 44 males) dentists (n=103 general dentists and 47 periodontologists) that responded to a questionnaire designed to retrieve cross-sectional information related mainly to their level of training and time of experience in practice, as well as their personal decision for managing four patients with periodontal disease. Bivariate analyses were performed to test the association between the clinical decisions and the professional information collected from the dentists.

Results

In specific cases, periodontologists decided to maintain more teeth than general dentists (p<0.05). In other cases, dentists with more years of experience in practice decided to opt for more extractions (p<0.05). The level of periodontal disease (50-92%), poor oral hygiene (42.6-67.3%) and lack of alveolar bone structure (43.2-79.3%) were the most prevalent reasons behind the decision for extractions.

Conclusions

An advanced level of training in Dentistry, especially Periodontology, and more years of experience in practice may lead to more well-founded decisions on whether extracting teeth or not in case-specific scenarios.

Predoctoral Dental Education in Tooth Prognosis and Treatment Complexity: A Survey of U.S. Dental Schools

The aim of this study was to determine the educational methods and tools used to teach tooth prognosis and treatment complexity determination in U.S. predoctoral dental programs. In 2018, an online survey was emailed to the academic deans of all 66 accredited U.S. dental schools. Of these, 42 schools responded (63.6%), and 36 schools completed the entire survey (54.5%). The methods reported for teaching tooth prognosis and case complexity determination varied widely among the participating schools. Among the respondents, 25% reported using the American Association of Endodontists' Endodontic Case Difficulty Assessment, while 10% reported having no specific method for teaching prognosis. The most common method for teaching overall treatment complexity was the Prosthodontic Diagnostic Index, which was used by 24% of the respondents. However, another 24% reported that their school did not have a specific method for teaching treatment complexity. Large percentages of the respondents reported that students sometimes or often made wrong tooth prognosis and case complexity determination (90% and 92%, respectively). The most prominent feedback provided by the respondents based on their experience was the importance of faculty standardization, the understanding of students' inexperience, and the need for an interdisciplinary approach. The majority of these respondents reported that their schools had specific methods of teaching prognosis and case complexity determination. However, there was a wide range of teaching practices related to the contents and levels of evidence.

Herodontics - is there a place for maintaining the apparently hopeless tooth?

The population is ageing and people are keeping their own teeth for much longer due in part to the efforts of the dental profession in restoring teeth and reducing the number of teeth being extracted. Along with this there is now an increasing expectation by patients that they will retain their own teeth as they age and that dental practitioners will have the knowledge and skills to help them retain their own teeth. Contemporary restorative materials and techniques have increased the range of options available to assist with maintaining the dentition, and many of these procedures enable minimally invasive and cost effective management of the teeth as an alternative to complex and expensive procedures. This paper discusses the restoration of compromised and failing teeth in the ageing patient, and looks at the various issues facing the ageing dentate patient and the dilemma of when to restore or when to extract. Ultimately it is hoped that maintaining healthy teeth for life may not only improve oral function and quality of life, but may in fact reduce the impact of the physical and psychological aspects of ageing.

In Vitro Fracture Strength of Teeth Restored with Lithium Disilicate Onlays with and without Fiber Post Build-Up

To our knowledge there is no data about the mechanical performance of indirect restoration adhesively cemented on teeth without an adequate build-up to provide the correct geometrical configuration. The aim of this study was to compare the fracture strength of human teeth restored with lithium disilicate onlays, with and without fiber post build-up.

METHODS

Twenty human mandibular molars were horizontally sectioned and divided into two groups (n = 10). No treatment was applied in group A. Teeth in group B were endodontically treated, built-up using fiber post and composite core and prepared with a circumferential chamfer providing a 1 mm circumferential ferrule. Lithium disilicate onlays were pressed and luted on teeth using dual-curing luting composite. Teeth were tested under static load. Failures were classified as restorable or not restorable. Failure loads were analyzed with one-way analysis of variance. Failure modes were compared using Pearson's Chi-square tests.

RESULTS

The mean fracture loads were 1383.5 N for group A and 1286.3 N for group B. No difference was found (p = 0.6). Ninety per cent of fractures were classified as not restorable in both groups, with no difference (p = 0.8).

CONCLUSIONS

For teeth restored with adhesive procedures and lithium disilicate onlays, the presence of build-up with fiber post to provide retention and resistance form does not influence the fracture strength.

Does professional experience save teeth? A survey among prosthodontists

OBJECTIVES

The aim of this study is to investigate the effect of clinical experience and educational background on clinical decision-making of dentists presented with two prosthodontic cases.

METHODS

A questionnaire-based survey was performed among 66 prosthodontists who were divided into two groups. The first group included clinicians from Belgium, Germany, and the Netherlands covering a wide spectrum of dental experience. The second (specialized) group consisted of German dentists performing their last module of a 3-year postgraduate master program in prosthodontics. Two patient scenarios of different complexities were presented to the participants who were asked to make an educated choice among seven therapeutic options.

RESULTS

Sixty-six dentists participated. For case #1, 22 therapeutic suggestions were offered within the international group (variation 54%), while 17 options were chosen in the specialized group (variation 68%). For case #2, five (variation 12%) and four (variation 16%) different therapeutic options were planned in the groups, respectively. Treatment planning in combination with implants was clearly preferred by dentists with an experience of 20 years or less. Conversely, participants with more experience favored more conventional treatments. All differences were statistically significant (p < 0.05).

CONCLUSION

Clinicians' experience and educational background had a clinically relevant influence on decision-making and treatment planning. A clear preference for implant-free therapies was noted for dentists with more than two decades of professional experience.

CLINICAL SIGNIFICANCE

In complex cases, clinicians with more than 20 years of professional experience tend to save questionable teeth rather than to resort to implants. This interindividual variation might less likely occur when more external evidence is taken into account during the decision-making process.

Influence of academic training in endodontics and implantology on decision-making in undergraduate students

PURPOSE

To evaluate the effect of academic training on decision-making in a group of undergraduates who have undergone training in endodontics and implantology.

BASIC PROCEDURES

A single group of undergraduate dentistry students (n = 65) was given a survey consisting of 15 endodontic cases. Each case included periapical radiographs and clinical photographs. Students were asked to select one of the eight proposed treatments. In their 4th year, the students first responded to the survey after completing endodontics. One year later, after completing their studies in implantology, the same students completed the same survey again.

MAIN FINDINGS

Under the conditions of this study, differences in undergraduate training significantly affected treatment decisions.

PRINCIPAL CONCLUSIONS

Undergraduate decision-making was affected by academic training.

Prognostic factors of single-visit endodontic and restorative treatment under general anaesthesia for special needs patients

The aim of this study was to evaluate the longevity of teeth with single-visit endodontic and restorative treatment under general anaesthesia (GA) for special needs patients and to investigate factors associated with survival and success. Data were collected from 381 teeth in 203 patients [mean (s.d.) age = 27·0 (14·1)]. All endodontic and restorative procedures were performed during a single GA session except for cementation of crowns in the cases requiring crown restoration (38%). A total of 267 teeth (70·6%) were followed-up for 6-81 months [mean (s.d.): 32·7 (20·0)]. Patients and teeth with and without follow-up were compared. Kaplan-Meier analysis with generalised Wilcoxon test was used to compare the mean survival and success period. Cox proportion hazard regression model was applied for multivariate analysis. At the end of the observation period, 10 teeth had a crown fracture (5-year survival rate = 89·8%), and an additional 10 teeth had primary or secondary caries (5-year success rate = 86·4%). Risk factors associated with survival were age (>40), non-parental caregiver, cooperation level and periodontal disease. A soft diet was an additional risk factor against the success of teeth. Single-visit endodontic and restorative treatment under GA showed favourable outcomes, suggesting a promising treatment option for special needs patients. Patient- and dental-specific circumstances need to be carefully considered to enhance the longevity of reconstructed teeth.

Preserving esthetics, occlusion and occlusal vertical dimension in a patient with fixed prostheses seeking dental implant treatment

The preservation of esthetics and occlusal vertical dimension is critical in patients with existing full-arch tooth-retained fixed prostheses. This clinical report describes the provision of a maxillary immediate complete denture in a patient with a maxillary full-arch fixed dental prosthesis over nonviable teeth. The existing fixed dental prosthesis was used in the fabrication of the maxillary immediate complete denture to preserve esthetics. The technique involved recording and preservation of the occlusal vertical dimension and occlusion of the existing prosthesis. The technique is simple, quick, cost-effective and less challenging clinically and technically.

Prosthodontic decision-making relating to dentitions with compromised molars: the perspective of Swedish General Dental Practitioners

The aim of this investigation was to study the clinical prosthodontic decision-making process relating to dentitions with compromised molars among Swedish general dental practitioners (GDPs). Eleven Swedish GDPs were purposively selected, and all agreed to participate. Then, in-depth, semi-structured interviews were conducted and covered treatment considerations concerning two authentic patient cases, initially with complete dental arches, and later, a final treatment based on a shortened dental arch (SDA) was discussed. The cases involved patients with compromised teeth situated mainly in the molar regions. One patient suffered from extensive caries and the other from severe periodontal disease. Qualitative content analysis was used to analyse the data. In the systematic analysis, two main categories were identified: holistic and functional approach. Among the interviewed GDPs, focus was put on patients' needs, background history and motivation for treatment as well as the preservation of molar support. Within the limitations of this study, the following can be concluded: keeping a dental arch with molars seems to be important to Swedish general dental practitioners. The SDA concept does not seem to have a substantial impact on the prosthodontic decision-making relating to dentitions with compromised molars. The dentist's experiences, as well as colleagues' or consulting specialist advice together with aetiological factors and the patient's individual situation, influence the decision-making more than the SDA concept. The conflicting results in the prosthetic decision-making process concerning the relevance of age and the need for molar support need further investigation, for example based on decisions made in the dentist's own clinical practice.

Treatment of a Periodontic-Endodontic Lesion in a Patient with Aggressive Periodontitis

Case Description. This case report describes the successful management of a left mandibular first molar with a combined periodontic-endodontic lesion in a 35-year-old Caucasian woman with aggressive periodontitis using a concerted approach including endodontic treatment, periodontal therapy, and a periodontal regenerative procedure using an enamel matrix derivate. In spite of anticipated poor prognosis, the tooth lesion healed. This case report also discusses the rationale behind different treatment interventions. Practical Implication. Periodontic-endodontic lesions can be successfully treated if dental professionals follow a concerted treatment protocol that integrates endodontic and periodontic specialties. General dentists can be the gatekeepers in managing these cases.

Treatment Options for Anterior Teeth with Questionable Prognosis: Critical Factors in Determining Whether to Maintain or Extract

Implants nowadays have conquered the majority of prosthetic restorations in the everyday clinical practice. As a result there has been a tendency among many clinicians to believe that implant therapy is the best solution in every clinical case, even if extraction of natural tooth with questionable prognosis is necessary. The value of natural teeth has been recently reconsidered. An implant not placed under ideal circumstances, may lead to a compromised result especially in the anterior maxillary region. Conversely natural teeth, even in a compromised clinical condition, maintain proprioception and can be adapted to the stresses of functional loading. The most demanding task in daily clinical practice is the treatment plan. The role of the clinician is more complicated for the anterior teeth where the patient's expectations and the esthetic criteria complicate the objective way of thinking. Therefore, a frequent dilemma in dental practice is whether to maintain an anterior tooth with a questionable prognosis or to extract it and replace it with an implant. The aim of this article is to approach the dilemma of extraction or maintenance of anterior teeth with a questionable prognosis through a series of clinical cases focusing on the factors that should be taken under consideration.

CLINICAL SIGNIFICANCE

Dental implants offer increased possibilities in the restoration of the anterior maxillary teeth. In specific clinical cases however a satisfying clinical result can be achieved by maintaining the existing natural teeth even if they have a questionable prognosis and a more complicated treatment plan may be needed. (J Esthet Restor Dent, 2016).

Should retention of a tooth be an important goal of dentistry? How do you decide whether to retain and restore a tooth requiring endodontic treatment or to extract and if possible replace the tooth?

Whether a questionable tooth should be treated endodontically or extracted, is still a dilemma clinicians encounter every day. With advances in technology such as implantology, deciding whether or not to save a tooth is still not clear. Local site-specific factors and patient-related factors that may affect the longevity of a particular tooth should be considered in preparing the treatment plan. Long-term success rates for root canal therapy and implant-supported crowns demonstrate similar outcomes. A choice between these alone is not sufficient in the decision-making process. Only following a systematic evaluation of the reasons for and against tooth retention as directed by each individual case, can the best option be decided.

Treatment strategies for infraoccluded dental implants

Single-tooth implants in the maxillary anterior region have the highest risk of esthetic complications from infrapositioning due to continuing maxillary growth and the eruption of adjacent teeth. Although the placement of anterior single-tooth implants should normally be postponed, particularly girls and young women with a hyperdivergent growth pattern, if an infraposition of an implant is present, then thorough examination and strategic planning are required. According to the severity, the strategic treatment options are as follows: simple retention; adjustment or replacement of the implant restoration, possibly including adjacent teeth; surgical implant repositioning by segmental osteotomy combined with osseodistraction; or submergence or removal of the implant. With the patient presented, an interdisciplinary approach that combined orthodontic alignment, surgical segmental osteotomy, distraction osteogenesis, and restorative features offered the opportunity to realign the adjacent teeth into the arch and to harmonize the gingival contour by means of continuous soft tissue enlargement and adaptation.

Conventional prosthodontic management of partial edentulism with a resilient attachment-retained overdenture in a patient with a cleft lip and palate: a clinical report

Recent advances in surgery and orthodontics have resulted in improvements in the management of patients with a cleft lip or palate. Early surgical intervention and bone-grafting procedures have frequently been used to ensure closure of the cleft and continuity of the alveolar bone. However, a need for the prosthodontic management of patients with a cleft palate still exists. Most frequently, the indication is to restore the edentulous spaces located anteriorly in the vicinity of the residual cleft defect. In addition to improving the esthetic outcome, prosthodontic management also is required to restore function, especially occlusion and speech. This clinical report illustrates the management of an adult patient with a unilateral cleft of the lip and palate who required prosthodontic rehabilitation after surgery. The patient had previously undergone multiple surgeries and did not want to consider implant therapy as a treatment option. Thus, the patient was managed with fixed and removable prosthodontics with a maxillary overdenture prosthesis retained by microextracoronal resilient attachments, which were laser welded onto crowns on abutment teeth to obtain a functionally and esthetically acceptable result.

Importance of a distal proximal contact on load transfer by implant-supported single adjacent crowns in posterior region of the mandible: a photoelastic study

Objective

This study aimed to evaluate the importance of a distal proximal contact on the load transfer to the posterior region of the mandible by non-splinted adjacent implant-supported crowns using photoelastic stress analysis.

Material and Methods

A rectangular model (68x30x15 mm) was made of polymethylmethacrylate resin to simulate half of the mandibular arch. One model was completed with resin replicas representing the first premolar and second molar and with two 3.75 mm dia.x11 mm internal hexagon threaded implants replacing the second premolar and first molar. The other model was manufactured in the same way but without the second molar. Both models were duplicated using photoelastic resin. The roots of the teeth replicas were covered with a layer of polyether impression material to simulate the periodontal ligament. Two different vertical loads were applied to the crowns as follows: 1 - single static point load alternately applied to the crowns replacing the second premolar and first molar (50 N); 2 - simultaneous static point loads applied to both of the crowns replacing the second premolar and first molar (100 N). The resulting isochromatic fringe pattern in the photoelastic model was monitored and photographed.

Results

All loading conditions studied showed that the presence of the second molar has changed the load transmission and the pattern of stresses.

Conclusion

Results showed that the presence of a second molar proximal contact can help minimize the stresses around the implants.