In the Dental Implant Era, Why Do We Still Bother Saving Teeth?

Risk factors associated with implant sites prepared by orthodontic treatment: a systematic review

The patient's health and quality of life would probably be improved with dental implant. This study aimed to evaluate the risk factors associated with dental implants place by orthodontic treatment. In this study, information on risk factors associated with implants of sites prepared, radiology stereotypes and hospitalized were obtined from databases such as Scopus, Google scholar and PubMed, and 58 articles were included for this purpose. After analyzing the articles, 24 articles were not accepted and 34 articles were accepted, then, 16 articles were miscarriage and 18 articles were scientific sources. The results showed that orthodontic treatment has a significant effect on a person's sense of beauty and would possibly increase self-confidence and quality of life. The stability of the implant in the healing phase depends on the quality and quantity of the bone. Also, the width of the bone is one of the important issues in creating a successful treatment. When an implant fails, problems and symptoms of failure usually occur within the first year after surgery. After one year, there is only about a 1% chance of failure, and on average only 1% of all implants fail each year.

Is dynamic computer-assisted surgery more accurate than the static method for dental implant placement? A systematic review and meta-analysis

STATEMENT OF PROBLEM

Dynamic computer-assisted surgery for dental implant placement has become popular, but systematic comparisons of the accuracy of computer-assisted surgery with static surgery are lacking.

PURPOSE

The purpose of this systematic review and meta-analysis was to determine evidence on the difference in the accuracy of dynamic computer-assisted surgery compared with the static method for dental implant placement.

MATERIAL AND METHODS

A systematic search was conducted in 3 electronic databases: PubMed, Ovid, and Cochrane. Studies conducted on dental implants that compared the accuracy of positioning implants with a dynamic system with that of a static system were included. Randomized clinical trials, prospective and retrospective cohort studies, and in vitro studies were included in the review. Review articles, case reports, letters, opinion articles, commentaries, and nonpeer-reviewed literature were excluded.

RESULTS

Of the 26 full-text articles, 14 fulfilled the inclusion criteria. Of these, 2 were randomized clinical trials, 2 were prospective studies, and 1 was a retrospective cohort study. The remaining 9 were in vitro studies. A total of 1633 implants were placed with the static and 902 with the dynamic method. A significant mean difference (-0.51 degrees [95% CI: -0.90, -0.13]) between dynamic and static systems was only observed in the angular deviation of in vitro studies (P=.009). Meta-analysis was performed using Review Manager statistical software and forest plots were generated.

CONCLUSIONS

A difference was found in the angular deviation of implants placed with the dynamic approach compared with the static system. The dynamic system was better, but this difference was not demonstrable in clinical studies. No significant difference was found in the apical and coronal deviations of the dynamic and static systems.

Flapless Decoronation: A Minimally Invasive Approach

Traumatic injuries to the permanent dentition are most common in children. In severe dentoalveolar injuries, especially avulsion and intrusion, dentoalveolar ankylosis is a common complication, leading to adverse effects on the developing alveolar bone and interfering with the eruption of the adjacent teeth. The decoronation procedure was suggested in 1984 to reduce these side effects related to ankylosis. The objective of the current publication is to describe a minimally invasive, flapless decoronation procedure aimed to minimize and simplify the surgical procedure of decoronation, and ease its clinical acceptance, particularly in young children. The technique is described in a detailed protocol and demonstrated in two cases. Under local anesthesia, the dental crown is removed, and the root is reduced by 1.5-2.0 mm apically to the marginal bone crest. The root canal content is then removed, allowing it to fill with blood. The socket is coronally sealed with a porcine-derived collagen matrix (PDCM) sutured using the "parachute" technique over the resected root, allowing close adaptation to the surrounding soft tissue. In conclusion, the presented technique of flapless decoronation is a modification of the classic decoronation procedure, which can be used as a minimally invasive technique to simplify the surgical procedure and the post-operative process.

Paxillin tunes the relationship between cell-matrix and cell-cell adhesions to regulate stiffness-dependent dentinogenesis

Mechanical stiffness is recognized as a key physical factor and directs cell function via a mechanotransduction process, from extracellular physical cues to intracellular signaling cascades that affect transcriptional activity. Cells continually receive mechanical signals from both the surrounding matrix and adjacent cells. However, how mechanical stiffness cue at cell-substrate interfaces coordinates cell-cell junctions in guiding mesenchymal stem cell behaviors is poorly understood. Here, polydimethylsiloxane substrates with different stiffnesses were used to study mechanosensation/transduction mechanisms in controlling odontogenic differentiation of dental papilla cells (DPCs). DPC phenotypes (morphology and differentiation) changed in response to the applied force derived from stiff substrates. Significantly, higher expression of paxillin on stiffer substrates promoted DPC dentinogenesis. Upon treatment with siRNA to knockdown paxillin, N-cadherin increased mainly in the cytomembrane at the area of cell-cell contacts, whereas β-catenin decreased in the nuclei. The result of a double luciferase reporter assay showed that stiffness promoted β-catenin binding to TCF, which could coactivate the target genes associated with odontogenic differentiation, as evidenced by bioinformatics analysis. Finally, we determined that the addition of a β-catenin inhibitor suppressed DPC mineralization in all the stiffness groups. Thus, our results indicated that a mechanotransduction process from cell-substrate interactions to cell-cell adhesions was required for DPC odontogenic differentiation under the stimulation of substrate stiffness. This finding suggests that stem cell fate specification under the stimulus of stiffness at the substrates is based on crosstalk between substrate interactions and adherens junctions, which provides an essential mechanism for cell-based tissue engineering.

Research on skull trauma biomechanical stress distribution in case of dental implants existence

BACKGROUND: When the jaw bone is subjected to an external force, the stress is transmitted from the force point along the alveolar bone to the skull and skull base. In the case of a dental implant, the stress distribution is mainly dependent on the implant position, type, and mechanical properties. OBJECTIVE: To investigate the dental implant position influence on the stress distribution and transmission in case of facial frontal trauma. Furthermore, the correlation between facial trauma and skull trauma in the case of a dental implant exists. METHODS: In this study, a Finite Element Method (FEM) model was constructed based on a real skull shape, size, and anatomy. Dental implants were modeled based on imported CAD Data. Five cases were investigated including no dental implant and the replacement of teeth no. 18, 19 20 and 21. Facial trauma was mimicked by applying an external load on the lower frontal jaw. Finally, the stress distribution based on the bone geometry and implant position were evaluated and compared. RESULTS: Results suggested that a dental implant could significantly influence the stress distribution in the skull in case of facial trauma. In addition, the dental position greatly affects stress transmission from the mandible to the skull bones through the zygomatic arch. CONCLUSION: The position of the dental implant could have a significant role in stress transmission and distribution in case of facial or even brain trauma. Thus, increasing the possibility of a correlation between facial and brain trauma.

Compromised Teeth Preserve or Extract: A Review of the Literature

Multiple systems and associated factors have been described in the literature to assess the prognosis of teeth with periodontal disease. Nowadays there is a tendency among clinicians to consider implants as the best solution after tooth extraction, in cases of teeth with a questionable prognosis. However, the value of the natural tooth must be considered, as the proprioception of the periodontal ligament is preserved, and it adapts to stress during functional loads. We first review the literature focusing on analyzing the factors that should guide decision-making to maintain or extract a tooth with a compromised periodontium. Then, we propose a schematic diagram of prognostic indicators to reflect the main factors to consider and the survival rate that each one represents when preserving or extracting a tooth.

Preserving natural teeth versus extracting them: a willingness to pay analysis

BACKGROUND

Maximum willingness to pay (WTP) for a health benefit is related to perceived value. The goal of this study was to find out how much Iranian healthy people would be willing to pay to keep their natural teeth instead of having them pulled. This was done separately for the anterior and posterior teeth.

METHODS

The highest value was posed as an open-ended question in this cross-sectional analysis conducted in 2021. Four distinct scenarios for treating a tooth with a poor prognosis for natural tooth preservation versus extraction were offered. WTP for the preferred treatment option was asked for painful and painless anterior and posterior teeth separately. A two-stage hurdle approach was employed to determine factors influencing the WTP for a hopeless case. The level of significance was fixed at 0.05.

RESULTS

Out of 795 individuals, 355 (44.7%) were male and 209 (26.3%) had poor self-stated dental health. Over 65% of those interviewed said they wanted to keep their teeth. The mean WTP was highest for dental preservation up to 94 USD and the lowest was for extraction without replacement 19 USD. The WTP for anterior tooth therapy was greater than the WTP for posterior dental care, regardless of treatment type or tooth discomfort. Participants with higher education, jobs, income-to-expenditure matching, older age, preference for the treatment in a private office, and female gender (except for WTP for a painful posterior tooth) were more likely to have a WTP of at least 1 USD.

CONCLUSION

The average WTP for treatment of teeth with a poor prognosis was lower than the average fee charged in dental facilities, and more than 65% of participants preferred to keep their teeth. Regardless of the treatment option or whether it was painful or not, WTP for anterior teeth treatment was higher than for posterior teeth. Generally, we found that sociodemographic factors influenced WTP decision-making the most. This study has practical implications for public oral health policymakers and insurance organizations.

Replacement of an existing maxillary anterior fixed dental prosthesis, redo another fixed dental prosthesis, or convert to implants

OBJECTIVE

The purpose of this article is to discuss the considerations that need to be evaluated when considering the replacement of an existing maxillary anterior fixed dental prosthesis (FDP) with another FDP, or when to consider converting to implants and individual crowns on the previous abutment teeth.

OVERVIEW

The need to replace unesthetic or failing maxillary anterior FDPs is something all restorative dentists will be faced with multiple times in their careers. Given the emphasis over the past few decades on utilizing implants for tooth replacement as opposed to a tooth supported FDP, the question becomes when is converting the existing FDP to implants and single crowns an appropriate choice, as opposed to redoing a new FDP. This article will focus on the risks of choosing to convert to an implant solution, and the risks of redoing the tooth supported FDP. Multiple systematic reviews on each approach will be used to aid in the decision process. The most significant risks for both approaches will be identified, and a chart of the key parameters to assess will be presented, along with their impact.

CONCLUSIONS

The statistical outcomes at 5 and 10 years of tooth supported FDPs, and Implant based restorations are very similar if certain clinical parameters are met, namely vital healthy abutment teeth for the FDP, and adequate bone and soft tissue for the implant-based restoration. If one abutment tooth is compromised the long-term prognosis drops significantly and converting to an implant-based restoration may be more predictable. Similarly, if adequate bone and soft tissue cannot be obtained through surgical augmentation procedures, using a connective tissue graft for the ridge, and redoing the FDP may obtain a more acceptable esthetic result.

CLINICAL SIGNIFICANCE

A significant number of maxillary anterior FDPs exist that will need replacement in the future. Given the desire of many dentists to utilize implants when possible, there can be a tendency to automatically treatment plan an implant-based approach for replacement of the existing FDP. Certainly, most clinicians would favor an implant-based tooth replacement rather than preparing unrestored teeth to place an FDP, but when an existing FDP exists, the teeth have already been prepared for full coverage in most instances. In addition, for most long term existing FDPs, there is a significant change in the vertical and horizontal dimension of the bone and soft tissue that can make getting an acceptable esthetic result with an implant challenging. This article provides a systematic approach to identifying when redoing the FDP may be preferable, or when converting to an implant-based approach is a better choice.

Long term clinical performance of 10 871 dental implants with up to 22 years of follow-up: A cohort study in 4247 patients

Background

The present retrospective study was aimed to assess the long‐term clinical performance of dental implants in a cohort study of 4247 patients.

Methods

A longitudinal observational cohort study was done on all implants performed by a single periodontist from July 1995 to April 2019. The main outcome variables of this study were implant failure and marginal bone level around implants.

Results

The study participants received a total of 10 871 implants with a mean of 2.56 implants per patient. The cohort was followed‐up to 22.2 years (mean = 4.5 ± 4.2). Among the 4247 patients of the current study, 140 patients (3.3%) experienced a combined total of 178 implant failures. According to life table analysis, at the implant level the cumulative survival rate at 3, 5, 10, and 15 years was 98.9%, 98.5%, 96.8%, and 94.0%, respectively while at patient level was 97.4%, 96.7%, 92.5%, and 86% at 3, 5, 10, and 15 years. Patients with multiple units were at a greater risk for having an implant failure. Baseline bone level was 0.09 ± 0.28 mm while at 8–10 years the mean bone level was 0.49 ± 0.74 mm. The incidence of peri‐implant mucositis at the implant level was 9.4% at 2–3 years, 9.3% at 4–5 years, 12.1% at 6–7 years, and 11.9% at 8–10 years. The incidence of peri‐implantitis was 2%, 2.6%, 3.2%, and 7.1% at 2–3, 4–5, 6–7, and 8–10 years, respectively. Cigarette smoking and diabetes mellitus were positively correlated with implant failure.

Conclusions

Though the results are promising and encouraging in terms of survival and bone level over time, it is important to emphasize the potential risk factors and consider them prior to dental implant placement.

Guided Osteotomy and Guided Autotransplantation for Treatment of Severely Impacted Teeth: A Proof-of-Concept Report

INTRODUCTION

The aim was to present a novel surgical technique using virtually preplanned 3-dimensional (3D)-printed templates for guided osteotomies. These were to ensure atraumatic uncovering of a severely impacted donor tooth including guided drilling of the recipient alveolus followed by a secure autotransplantation procedure.

METHODS

This report presents an autotransplantation procedure of a 14-year-old patient with a severely impacted second premolar and extensive contact to the roots of the adjacent teeth and the inferior alveolar nerve. Autotransplantation of the impacted premolar was virtually performed using modified methods from guided implant surgery in order to prefabricate 3D-printed templates with the aid of a fully digital workflow.

RESULTS

Satisfactory treatment could be achieved using surgical templates for guided osteotomies of the surgical access, guided drilling of the recipient site, and occlusal reference template ensuring autotransplantation in the appropriate 3D location of the graft. An atraumatic approach could be ensured with an extraoral time of 46 seconds by 1 fitting attempt; no injuries or altered sensation of the inferior alveolar nerve were present. A vital natural tooth could be observed.

CONCLUSIONS

This innovative technique uses for the first time a fully implemented digital workflow for guided osteotomies, guided drilling, and guided autotransplantation of a severely impacted tooth. 3D-printed templates could ensure a guided atraumatic approach and facilitate highly complex treatments by virtually implementing recommended guidelines in future autotransplantations.