The survival of periodontally treated molars in long-term maintenance: A systematic review and meta-analysis

AIM

This systematic review and meta-analysis aimed to determine the survival of periodontally treated molars during maintenance care and identify the risk factors associated with molar loss among patients with periodontitis who received professional periodontal therapy and maintenance.

MATERIALS AND METHODS

Longitudinal studies with a minimum follow-up duration of 5 years published until 28 August 2023 were retrieved from the following databases: the Cochrane Library, Embase, MEDLINE and Web of Science. All included studies reported data on molar retention. Meta-analysis was performed using Review Manager 5.4. A modified version of the Newcastle-Ottawa Scale was used to evaluate the study quality. Statistical results of analyses of the overall survival rate and molar loss are presented as estimated standardized mean differences, whereas the results of the analyses of risk factors are presented as risk ratios with 95% confidence intervals (95% CIs).

RESULTS

From among the 1323 potentially eligible reports, 41 studies (5584 patients, 29,908 molars retained at the beginning of maintenance therapy, mean follow-up duration of 14.7 years) were included. The pooled survival rate of the molars during maintenance therapy was 82% (95% CI: 80%-84%). The average loss of molars was 0.05 per patient per year (95% CI: 0.04-0.06) among the patients receiving long-term periodontal maintenance (PM) therapy. Fifteen factors were examined in this meta-analysis. Six patient-related factors (older age, lack of compliance, smoking, bruxism, diabetes and lack of private insurance) and five tooth-related factors (maxillary location, high probing pocket depth, furcation involvement, higher mobility and lack of pulpal vitality) were identified as risk factors for molar loss during maintenance therapy.

CONCLUSIONS

The findings of the present study suggest that the long-term retention of periodontally compromised molars can be achieved. The average number of molars lost per decade was <1 among the patients receiving long-term PM therapy. Older age, noncompliance, smoking, bruxism, diabetes, lack of private insurance coverage, maxillary location, furcation involvement, higher mobility, increase in the probing pocket depth and loss of pulpal vitality are strong risk factors for the long-term prognosis of molars.

Maxillary root amputation: Case report with a 14-year-follow-up and updated mini review

Root resection is performed to create a maintainable furcation area in teeth with advanced periodontitis. However, the long-term feasibility of this treatment remains controversial. We present a case in which distal root resection in a maxillary molar successfully preserved the form and function of the dentition for approximately 14 years.

Present Status and Future Directions - Surgical Endodontics

Endodontic surgery encompasses several procedures for the treatment of teeth with a history of failed root canal treatment, such as root-end surgery, crown- and root resections, surgical perforation repair, and intentional replantation. Endodontic microsurgery is the evolution of the traditional apicoectomy techniques and incorporates high magnification, ultrasonic root-end preparation and root-end filling with biocompatible filling materials. Modern endodontic surgery uses the dental operating microscope, incorporates cone-beam computed tomography (CBCT) for preoperative diagnosis and treatment planning, and has adopted piezoelectric approaches to osteotomy and root manipulation. Crown- and root resection techniques have benefitted from the same technological advances. This review focuses on the current state of root-end surgery by comparing the techniques and materials applied during endodontic microsurgery to the most widely used earlier methods and materials. The most recent additions to the clinical protocol and technical improvements are discussed, and an outlook on future directions is given. While non-surgical retreatment remains the first choice to address most cases with a history of endodontic failure, modern endodontic microsurgery has become a predictable and minimally invasive alternative for the retention of natural teeth.

Outcomes reporting in systematic reviews on surgical endodontics: A scoping review for the development of a core outcome set

BACKGROUND

Evidence-informed decision-making in healthcare relies on the translation of research results to everyday clinical practice. A fundamental requirement is that the validity of any healthcare intervention must be supported by the resultant favourable treatment outcome. Unfortunately, differences in study design and the outcome measures evaluated often make it challenging to synthesise the available research evidence required for secondary research analysis and guideline development. Core outcome sets (COS) are defined as an agreed standardised set of outcomes which should be measured and reported as a minimum in all clinical trials on a specific topic. The benefits of COS include less heterogeneity, a reduction in the risk of reporting bias, ensuring all trials contribute data to facilitate meta-analyses, and given the engagement of key stakeholders, it also increases the chances that clinically-relevant outcomes are identified. The recognition of the need for COS for assessing endodontic treatment outcomes lead to the development of Core Outcome Sets for Endodontic Treatment modalities (COSET) protocol, which is registered (No. 1879) on the Core Outcome Measures in Effectiveness Trials (COMET) website.

OBJECTIVES

The objectives of this scoping review are to: (1) identify the outcomes assessed in studies evaluating surgical endodontic procedures; (2) report on the method of assessment used to measure the outcomes; (3) and assess selective reporting bias in the included studies. The data obtained will be used to inform the development of COS for surgical endodontics.

METHODS

A structured literature search of electronic databases and the grey literature was conducted to identify systematic reviews on periradicular surgery (PS), intentional replantation (IR) and tooth/root resection (RR), published between January 1990 and December 2020. Two independent reviewers were involved in the literature selection, data extraction and the appraisal of the studies identified. The type of intervention, outcomes measured, type of outcomes reported (clinician- or patient-reported), outcome measurement method, and follow-up period, were recorded using a standardised form.

RESULTS

Twenty-six systematic reviews consisting of 19 studies for PS, three studies for IR and four studies for RR were selected for inclusion. Outcome measures identified for PS and IR included pain, swelling, mobility and tenderness, outcomes related to periodontal/soft tissue healing (including sinus tract), periradicular healing, tooth survival, life impact (including Oral-Health-Related-Quality-of-Life), resource use and/or adverse effects. For RR, in addition to tooth survival, endodontic complications, and adverse effects, the outcome measures were primarily periodontal-related, including pocket depth reduction, attachment gain, periodontal disease, and periodontic-endodontic lesions. The majority of outcome measures for PS, IR, and RR were assessed clinically, radiologically and/or via patient history. Specific tools such as rating scales (Visual Analog Scale, Verbal rating Scale, Numerical Rating Scale, and other scales) were used for the assessment of pain, swelling, and tenderness, and validated questionnaires were used for the assessment of oral health-related quality of life. The range of follow-up periods were variable, dependent on the outcome measure and the type of intervention.

CONCLUSIONS

Outcome measures, method of assessment and follow-up periods for PS, IR and RR were identified and categorised to help standardise the reporting of outcomes for future research studies. Additional outcome measures that were not reported, but may be considered in the COSET consensus process include loss of root-end filling material, number of clinic visits, surgery-related dental anxiety and muco-gingival aesthetic-related measures, such as scarring, black triangles, root surface exposure, and tissue discolouration.

Can a single molar root act as a whole tooth?

This clinical case describes the longitudinal outcome of a radisected upper molar root. The palatal root acted as an abutment and was finalized with a double-premolar-shaped metal-resin crown with two rests on the adjacent teeth. Fifteen years later, the root and its crown were still in place, with no pathologic pocket probing depth and lack of inflammation; the tooth was still in function with no signs of periodontal breakdown. This therapeutic option seemed to have been biologically respectful and maintains the possibility to provide future implant therapy.

Resective surgery for the treatment of furcation involvement: A systematic review

OBJECTIVE

To evaluate the benefit of resective surgical periodontal therapy (root amputation or resection, root separation, tunnelling) in periodontitis patients exhibiting class II and III furcation involvement (FI) compared with non-surgical treatment (SRP) or open flap debridement (OFD).

MATERIAL

Outcomes were tooth survival (primary), vertical probing attachment gain, and reduction in probing pocket depth (secondary) evidenced by randomized clinical trials, prospective and retrospective cohort studies and case series with ≥ 12 months of follow-up. Search was performed on 3 electronic databases from January 1998 to December 2018.

RESULTS

From a total of 683 articles, 66 studies were identified for full-text analysis and 7 studies finally included. Six hundred sixty-seven patients contributed 2,021 teeth with class II or III FI. Data were very heterogeneous regarding follow-up and distribution of FI. A total of 1,515 teeth survived 4 to 30.8 years after therapy. Survival ranged from 38%-94.4% (root amputation or resection, root separation), 62%-67% (tunnelling), 63%-85% (OFD) and 68%-80% (SRP). Overall, treatment provided better results for class II FI than class III.

CONCLUSION

Within their limits, the data indicate that in class II and III FI, SRP and OFD may result in similar survival rates as root amputation/resection, root separation or tunnelling.

Hemisection as a Conservative Management of Grossly Carious Permanent Mandibular First Molar

Hemisection of a molar denotes removal or separation of a root along with its accompanying part of crown. It is a suitable treatment option when the caries, resorption, perforation, or periodontal damage is restricted to one root while the other root is relatively healthy. Hemisection of the affected tooth helps to retain the tooth structure, surrounding alveolar bone, and may also facilitate the placement of fixed prosthesis. This case report describes the hemisection as a successful treatment method to save a grossly carious mandibular first molar with periodontal and periapical involvement. Hemisection and prosthetic rehabilitation yielded a satisfactory result. With careful treatment planning and precise surgical management, undesirable consequences of tooth loss were prevented.

Prosthetic rehabilitation of a mandibular root amputated molar using single crown

In teeth with furcation involvement, root amputation is one of the treatment choices. A challenge which a dentist may encounter with is the prosthetic treatment of such teeth when their adjacent teeth are intact. According to the current goal of operative dentistry based on conservative treatment, it would be desirable to do in a manner resulting in minimal damage to the adjacent sound teeth. In the following case report, a step-by-step conservative treatment sequences of a mandibular molar with distal root amputation which not involving surrounding teeth is described. During 18 months follow-up, the results were satisfactory.

Combined implant-residual tooth supported prosthesis after tooth hemisection: A finite element analysis

Tooth hemisection preserves partial tooth structure and reduces the resorption of alveolar bone. The aim of this study was to analyze the feasibility of preserving a molar after hemisection and inserting a dental implant with different prosthetic superstructures by means of finite element analysis. First, the distance between the root of the mandibular second premolar and the distal root of the first molar were measured in 80 cone beam computed tomography (CBCT) data sets. Based on these data, the lower right posterior jaw segment was reconstructed and the geometries of the appropriate implant were imported. Four models were created: (1) Hemi-1: An implant (3.7×9mm) replaced the mesial root of the molar, and a single crown was placed on the implant and residual tooth. (2) Hemi-2: Two separate crowns were generated for the implant and the residual tooth. (3) Single: An implant (5.5×9mm) with crown replaced the whole molar. (4) FPD: A 3-unit fixed partial denture combined the distal residual part of the molar and premolar. The results indicated that stresses in the cortical bone and strains in the majority region of the spongious bone were below the physiological upper limits. There were higher stresses in implant with the Hemi-1 and Single models, which had the same maximum values of 45.0MPa. The FPD models represented the higher values of stresses in the teeth and strains in PDL compared to other models. From a biomechanical point of view, it can be concluded that a combination of an implant and residual molar after tooth hemisection is an acceptable treatment option.

A novel approach for restoration of hemisectioned mandibular second molar with modified tunnel restoration: a case report

Hemisection refers to sectioning of a mandibular molar into two halves followed by removal of the diseased root and its coronal portion. Hemisection of a mandibular molar may be a suitable treatment option when the decay is restricted to one root and the other root is healthy. The retained root is endodontically treated and the furcation area is made self-cleansable. Retained tooth structure is restored as premolar which helps to reduce the masticatory load. Hemisection of mandibular molar was often referred to as premolarization. Studies showed that the remaining coronal structure influenced the fracture resistance of endodontically treated maxillary first premolars. Clinical experience showed the viability of tunnel restoration as an alternative to class II conventional cavity preparation in initial proximal lesion. This article discusses a case that presents the novel technique involved in restoration of the remaining hemisected tooth using modified tunnel restoration.

Alternatives for restoration of a hemisected mandibular molar

Hemisection is a common conservative treatment option for periodontally or endodontically compromised teeth. It is most likely to be performed on mandibular molars with class II or III furcation involvement. Their restoration is more critical than implant surgery to ensure the ability to masticate along with the ability to maintain good oral hygiene. There are various alternatives to restore such types of teeth: the remaining root restored as an individual tooth, restoring individual roots with either a molar or premolar morphology using the adjacent tooth as an abutment in a full coverage fixed partial denture, restoring individual roots with either molar or premolar morphology using an inlay type of restoration on the adjacent abutment tooth. This article reports two cases, one treated with molar morphology and an inlay type of restoration and the other with a premolar morphology and a full coverage fixed partial denture.

Root caries: a periodontal perspective

BACKGROUND AND OBJECTIVE

A prevailing dental problem in the periodontal patient is root caries. Specifically, periodontal involvement often results in root surfaces becoming exposed and at risk for this condition. Periodontal therapy often leads to increased gingival recession as well, and the associated increased root caries risk may compromise the long-term success and survival of periodontally treated teeth.This narrative review will address the topic of root caries in the periodontal patient, focusing on unmet research needs.

MATERIAL AND METHODS

The Medline database was searched to identify items dealing with root caries, in terms of clinical features, diagnosis, pathogenic mechanisms and histopathology, as well as epidemiology, focusing then on the relationship between root caries and periodontal disorders.

RESULTS

Although there is extensive literature on root caries, consensus is lacking regarding certain aspects, such as diagnostic criteria, prevalence within populations and indisputable risk factors. Advancing age could be an aggravating factor in susceptibility to root caries for the periodontal patient; however, definitive evidence in this regard is still missing. Similarly, full awareness of the increased risk of root caries in patients with periodontal disease or long-term periodontal treatment appears to be still lacking.

CONCLUSION

Research regarding root caries in age-specific (elderly) periodontal patients is needed. Improved oral hygiene practices, locally applied preventive measures, good dietary habits and regular dental check-ups are crucial approaches to prevent both periodontal disease progression and root caries. Periodontal patients with root exposure should follow a strict root caries prevention protocol, as an integral component of their periodontal maintenance therapy.

Maintenance of class III trifurcated molars versus implant placement in regenerated extraction sockets: long-term results of 2 cases

Studies to date have reached differing conclusions regarding the long-term prognosis of teeth with class III furcation involvement. Replacement of such teeth with implants could be an alternative. This report compares the treatment outcomes of 2 cases with similar disease progression: 1 treated by implant therapy and 1 maintained with nonsurgical periodontal treatment. Two patients with advanced chronic periodontitis and class III furcation involvement of all molars were treated. Case 1 received a conservative periodontal and antibiotic treatment, followed by 15 years of maintenance. In case 2, the molars were extracted and replaced with implants, and the implants were observed for 7 years. Clinical attachment level (CAL), probing attachment level (PAL), bleeding on probing, plaque index, and periodontal pathogens were recorded. Despite good compliance of case 1, periodontal pathogens were not eliminated and tissue destruction was not halted. The PAL outcomes of case 2 improved over time; mean PAL loss reached 0.35 mm/y in the first 3 years and then decreased to 0.01 mm/y. While CAL outcomes did not change in case 2, case 1 showed increased CAL loss after 8 years. Based on the limited findings of this case report, extraction of molars with class III furcation involvement and subsequent implant placement may render a better predictability of treatment outcomes than nonsurgical periodontal therapy in the cases of infection with periodontal pathogens.

Immediate Implant Placement in Fresh Mandibular Molar Extraction Socket: 8-Year Results. A Case Report

Recently, successful implant placement in fresh extraction sockets has been reported. In this case report, we present the results of an immediate implant placement in a fresh extraction socket of a mandibular molar with simultaneous bone regeneration using a nonresorbable membrane and no other graft materials. Clinical and radiographic findings acquired 8 years after implant placement demonstrated a stable peri-implant situation and confirmed a satisfactory treatment result.

Restorative options for the periodontal patient

Periodontal and restorative dentistry are mutually important facets of clinical dentistry. Today's clinicians have many treatment options at their disposal, including biotolerant restorative materials and implants, to maintain periodontal health. It is crucial for the clinician to understand the biologic principles that form the foundation for restorative reconstruction of the periodontally involved tooth. This article discusses new techniques and trends in the critical management of the restorations, particularly at the gingival margins, and explores the role of implant dentistry as an option for the restorative plan of the periodontal patient.