The significance of vertical platform discrepancies and splinting on marginal bone levels for adjacent dental implants.

OBJECTIVE: The aim of this retrospective study was to investigate the influence of vertical platform discrepancies for splinted and non-splinted adjacent implants on radiographic marginal bone loss (RMBL). METHODS: Data from January 2000 to February 2021 were collected from the electronic charts of 156 patients with 337 implants at the UCSF School of Dentistry. Five different implant restoration categories were evaluated for radiographic evidence of proximal RMBL. Patients with (1) two adjacent single crowns, (2) two adjacent splinted crowns, (3) three-unit bridges supported by two implants, (4) three adjacent single crowns, and (5) three adjacent splinted crowns. Inclusion required baseline radiograph taken at the time of prosthesis delivery or final impression, and follow-up radiographs at least 12 months after restorations have been in function. Measurements assessed included vertical distance between adjacent implant platforms and proximal RMBL around implants. Odds ratios (ORs) and 95% confidence interval (95% CI) of implants with ≥1 mm RMBL between different type of restorations were calculated. RESULTS: In general, prostheses supported by splinted adjacent implants demonstrated a significant association with the presence of ≥1 mm RMBL (OR = 2.55, 95% CI = 1.17-5.17, p = 0.018) when compared to prostheses supported by non-splinted adjacent implants. In addition, prostheses with a vertical platform discrepancy ≥0.5 mm demonstrated a significant association with the presence of ≥1 mm RMBL (OR = 4.30, 95% CI = 1.85 to 10.01, p = 0.007) when compared to prostheses with a vertical platform discrepancy <0.5 mm. When adjacent implants had ≥0.5 mm vertical platform discrepancy, the majority (66.67%) of three splinted adjacent crowns had at least one implant with ≥1 mm RMBL. This was followed by two splinted adjacent crowns (58.97%), three-unit bridge (25.93%), two single adjacent crowns (24.24%), and three single adjacent crowns (18.18%). When adjacent implants had ≥1 mm vertical platform discrepancy, there was an increased percentage of implants with ≥1 mm RMBL. The restorative design associated with the highest percent of implants with bone loss was three splinted adjacent crowns (70%), two splinted adjacent crowns (61.11%), three single adjacent crowns (40%), and three-unit bridge and two single adjacent implants (21.05%). Three splinted adjacent crowns were significantly associated with ≥1 mm RMBL when compared to three-unit bridge (OR 6.56, 95% CI 1.59-27.07). Similarly, two splinted crowns were significantly associated with ≥1 mm RMBL when compared to two single crowns (OR = 2.50, 95% CI = 1.08-5.79). CONCLUSION: Two or three adjacent implants placed with a vertical platform discrepancy, when splinted together, are associated with higherincidence of ≥1 mm RMBL than non-splinted restorations.

The Pattern of Tooth Loss for Periodontally Favorable Teeth: A Retrospective Study.

To retrospectively analyze local and systemic factors that resulted in the short-term tooth loss of teeth that were previously assigned a favorable prognosis in patients who were seen and treated over an observational five-year period. This retrospective study included the records of patients who had a minimum of two dental exams at least twelve months apart over a 5-year period. This study investigated extracted teeth with an initially favorable periodontal prognosis that were then divided into one of four categories based on the reason for extraction: caries, periodontal disease, endodontic reasons, or fracture. Patient- and tooth-related factors associated with the extracted teeth were recorded: crown-to-root ratio, initial pocket depth, initial periodontal diagnosis, maintenance interval, presence of existing restoration, furcation involvement, and systemic conditions. Data analysis was performed using a linear mixed model. A total of 50 patients with 111 teeth met the inclusion criteria for this study. A higher odds ratio (OR) for tooth loss due to caries, endodontic reasons, and fracture were found in teeth with a history of root canal treatment with an OR of 3.61, 3.86, and 2.52, respectively. For tooth loss due to periodontal disease, higher ORs were found in patients who were on anti-depressants (OR = 4.28) and patients who had an initial diagnosis of Stage III/IV periodontitis (OR = 2.66). In addition, teeth with initial probing depths ≥5 mm (OR = 4.32) and with furcation involvement (OR = 1.93) showed a higher OR for tooth loss due to periodontal disease. Within the limitations of this study, previously root-canal-treated teeth present a higher OR for early loss due to caries, recurrent endodontic lesions, or fracture. In addition, patients with anti-depressant medication use, sporadic maintenance, initial probing depths ≥5 mm, and furcation involvement represent a significantly higher OR of tooth loss due to periodontal disease even for initially favorable teeth.

A commentary on strategic extraction.

BACKGROUND: Advancements in strategies to maintain compromised teeth combined with a greater understanding of risks associated with dental implants invite a reassessment of the benefits of strategic extraction of a tooth with a questionable prognosis or of limited strategic value. METHODS: Evidence of the management of compromised teeth and decision making for strategic extraction was reviewed. Additionally, the risks for peri-implantitis were evaluated from the perspective of patient centric, biologic, and biomechanical complications. RESULTS: Recent clinical innovations support a more predictable maintenance of compromised dentition, and the clinical literature provides evidence of the risks associated with dental implants. CONCLUSIONS: Because of the improvements in dental management of compromised dentition, strategic extraction should be deferred, whenever possible, to avoid complications associated with peri-implantitis.

Treatment planning considerations in the older adult with periodontal disease.

Periodontal health in the elderly is influenced by numerous factors, including systemic conditions, patient compliance, age-associated changes, and restorative procedures. The numerous comorbidities seen in the elderly necessitate individualized approaches for treatment planning. In this paper, we review how age, comorbidities, oral hygiene, and restorative dental procedures collectively influence the treatment and management of the periodontium in the elderly. The elderly population is predicted to double in 30 years, which will have an economic impact the dental profession needs to plan for. Preventative and noninvasive treatment, supportive periodontal therapy, and patient-specific maintenance plans are imperative to maintaining oral health in the older population. Multiple coexisting changes, including xerostomia, altered wound healing, altered bone physiology, altered microbiome, and diminished plaque control, can add complexity to periodontal management. Considerations of the patient's general health, the selected periodontal treatment plan, and the selected completed restorative procedures need to be considered. The influence of caries, fixed prosthodontics, partial dentures, shortened dental arch, and implant therapy can have unintended impacts on periodontal health in the elderly. Adverse periodontal outcomes in the elderly can be minimized by carefully assessing the patient's medical history, impact of medications, functional needs, properly finishing and contouring restorations to avoid plaque accumulation, and designing restorations to allow access for hygiene. Partial dentures can be a source of plaque accumulation leading to periodontal disease, caries, and recession around abutment teeth. A shortened dental arch should be considered as a functional and cost-effective alternative to partial dentures. With dental implants, the patient's tissue phenotype, keratinized tissue quantity, risk of peri-implantitis, and patient access for maintaining adequate oral hygiene are all important to consider. Implant risk-assessment tools show promise by providing a systematic approach for early diagnosis to avoid future complications.

Use of mind maps in dental education: An activity performed in a preclinical endodontic course.

PURPOSE/OBJECTIVES: (1) to assess the ability of dental students to use mind maps to express the relationships of endodontic theory and technique; (2) to explore features illustrated from the highest- and lowest-graded mind maps; and (3) to evaluate improvements in successive mind maps from the same student. METHODS: A total of 31 second-year students were asked to configure a mind map on root canal cleaning-shaping and then 18 weeks later develop a second mind map on root canal obturation. Faculty visually analyzed the mind maps using a qualitative approach: a multilayered process of thematic analysis. Codes and themes were generated to investigate if students were able to express appropriate and evidence-based ideas on the topics (accuracy of relationships and depth of information presented). Two of the highest- and 2 of the lowest-graded mind maps for each activity were directly compared. Improvement by the same student from the first to second mind map was also evaluated based on trend/style and creativity. RESULTS: The majority of the students accurately expressed the scientific basis for root canal cleaning-shaping and obturation. The highest-graded mind maps displayed the biomedical and humanistic conceptions of critical thinking. In comparing the second mind map to the first, nearly 50% of the students incorporated more detail and artistic expression in the second map. CONCLUSIONS: using mind maps in dental education can benefit students with different learning styles and help the instructor to identify the level of conceptualization that the student had developed about a topic.

Dental Hygienists' Knowledge Regarding Dental Implant Maintenance Care: A national survey.

Purpose: Dental implants are now considered the standard of care for supporting dental restorations in edentulous areas. The purpose of this study was to explore the attitudes and practices of dental hygienists in the United States regarding dental implant assessment and maintenance care.Methods: A 34-item quantitative survey was developed and distributed nationally to a randomly selected sample of 10,000 dental hygienists from the American Dental Hygienists' Association (ADHA) email database. Responses were collected and analyzed via an online software program using frequency distributions for categorical variables.Results: A total of 2,018 dental hygienists participated for a response rate of 21%. The majority of respondents (98%) provided care to patients with dental implants. While the majority of respondents reported routinely assessing patients for bleeding/exudate, mobility, plaque/calculus, and tissue color around implants, 34% rarely/never checked for cement around implants, 31% rarely/never probed, and 54% rarely/never checked the occlusion. Nearly half of the respondents (44%) reported that they were unable to remove plaque as effectively from dental implants as from natural teeth. A majority (60%) reported using plastic/resin scalers, however only 7% of those who use plastic/resin scalers felt they were effective. While only 5% reported using air-polishers, 71% of the users felt they were effective. An oral irrigator was the most commonly recommended self-care hygiene aid for patients with implants and continuing education courses were the primary source of implant-related knowledge among respondents.Conclusion: The wide variation in implant-related assessment and maintenance care practices among dental hygiene respondents indicates a need for greater emphasis on evidence-based practices in dental hygiene curricula and in continuing education to ensure optimal care for patients with dental implants.

Image-Guided Ablation of Dental Calculus From Root Surfaces Using a DPSS Er:YAG Laser.

BACKGROUND AND OBJECTIVES: Recent studies have demonstrated that near-infrared (IR) imaging can be used to acquire high-contrast images of root caries and calculus on the root surfaces of extracted teeth at wavelengths longer than 1450 nm. The purpose of this study was to determine if image-guided laser ablation can be used to selectively remove calculus from tooth surfaces with minimal damage to the underlying sound cementum and dentin. MATERIALS AND METHODS: In this study, sequential near-IR images at 1500-1700 nm were used to guide a diode-pumped (DPSS) Er:YAG laser for the removal of calculus from the root surfaces of 10 extracted teeth. The selectivity of removal was assessed using digital microscopy, optical coherence tomography, and surface profilometry. RESULTS: Calculus was removed rapidly with minimal damage to the underlying sound cementum and dentin. Image-guided ablation achieved high-selectivity, the mean volume of calculus removal was more than 27 times higher than the mean loss of cementum. CONCLUSIONS: We have demonstrated that near-IR image-guided laser ablation can be used for the selective removal of calculus from root surfaces ex vivo. Additionally, we have demonstrated that a diode-pumped solid-state Er:YAG laser is well suited for selective removal. Lasers Surg. Med. © 2019 Wiley Periodicals, Inc.

The significance of surgically modifying soft tissue phenotype around fixed dental prostheses: An American Academy of Periodontology best evidence review.

BACKGROUND: This systematic review endeavored to investigate the effect of soft tissue phenotype modification therapy (PhMT-s) at sites with a tooth or an implant supported fixed dental prosthesis. METHODS: A comprehensive literature search was conducted by two independent examiners to identify relevant studies reporting differences in clinical, esthetic, or radiographic outcomes of interest between sites underwent PhMT-s and sites that remained untreated. Risk of bias assessment was calculated for all included studies. Meta-analyses involving endpoints of interest were performed when feasible. RESULTS: No controlled studies pertaining to tooth sites were identified. A total of six articles reporting on the outcomes of buccal soft tissue phenotype modification around implants were selected, of which, five were included in the meta-analyses. Quantitative analyses showed a weighted mean difference (WMD) of 0.98 mm (95% CI = 0.25 to 1.72 mm, P = 0.009) for change of tissue thickness; a WMD of -4.87% (95% CI = -34.27 to 24.53%, P = 0.75) for bleeding on probing (BOP); a WMD of 0.36 mm (95% CI = 0.12 to 0.59 mm, P = 0.003) for mucosal recession (MR); a WMD of 0.13 mm (95% CI = -0.11 to 0.36 mm, P = 0.30 for probing depth (PD); a WMD of 1.08 (95% CI = -0.39 to 2.55, P = 0.15) for pink esthetic score (PES), and a WMD of 0.40 mm (95% CI = -0.34 to 1.14 mm, P = 0.28) for marginal bone loss (MBL). CONCLUSIONS: Surgical modification of peri-implant soft tissue phenotype via PhMT-s may decrease the amount of MR. Future clinical trials are needed to warrant the clinical benefits of modifying soft tissue phenotype around tooth-supported restorations.

Effect of 0.2% peracetic acid disinfection on the horizontal dimension of implant framework indexed with two autopolymerized acrylic resins.

BACKGROUND: To minimize misfit between prosthesis and implant, the welding of the implant fixed partial denture (IFPD) framework is recommended and autopolymerized acrylic resin (AR) is the material of choice for the indexing process. As for any prosthetic device that comes into contact with saliva and blood in the oral cavity, IFPD indexed with AR must be disinfected before sending to the laboratory. However, disinfection procedures are often neglected for fear of shrinkage or distortion caused by a dimensional change of the acrylic resin. Peracetic acid is a high-level disinfectant agent at low concentrations and immersion time, with no reported toxic residues, and it is not inactivated in the presence of organic matter when compared to other disinfectants. This study aimed to evaluate the influence of 0.2% peracetic acid disinfectant solution after different storage media and times on the horizontal dimension of IFPD frameworks indexed with AR. MATERIAL AND METHODS: IFPD frameworks were indexed with two AR: group 1 Duralay and group 2 Pattern Resin LS. Each group was further divided into five subgroups according to disinfection procedure and storage medium: no disinfection and dry storage, no disinfection and water storage, 0.2% peracetic acid disinfection and water storage, 0.2% peracetic acid disinfection and peracetic acid storage, and 0.2% peracetic acid disinfection and dry storage. The horizontal dimension of the specimens and an average was established for analysis. Measurements were performed at four different storage times (hours): T0, T24, T48, T168. RESULTS: No statistical differences were found when T0 was compared to T168 for Pattern resin groups submitted to disinfection and storage in water (group 2b, p = 1.000) or peracetic acid solution (group 2c, p = 0.352). For Duralay groups, the use of peracetic acid solution did not affect the horizontal dimension of the specimens when T0 was compared to T168 only with water as a storage medium (group 1b, p = 1.000). Additionally, T0 did not differ from T24 for groups 1c (p = 0.553), 2b (p = 1.000), 2d (p = 0.234), and 2e (p = 1.000) and from T48 for groups 1d (p = 0.118) and 2b (p = 1.000). CONCLUSION: Within the studied conditions, the use of 0.2% peracetic acid can be safely used as a disinfectant solution regarding dimensional stability of AR-indexed IFPD until 7 days of storage. Horizontal discrepancies are dependent on acrylic resin type, time, and medium of storage.

Patient-Specific, Risk-Based Prevention, Maintenance, and Supportive Care: A Need for Action and Innovation in Education.

PURPOSE: To develop a competency-based curriculum framework for prevention, supportive care, and maintenance for use in educational and patient care programs and to seek consensus on an overarching competency statement that embraces these critical learning and patient care concepts. MATERIALS AND METHODS: A preliminary survey of current preventive and maintenance practices in U.S. dental and prosthodontic programs was completed and summarized with quantitative analysis. The American College of Prosthodontists organized a one-day consensus workshop with 14 participants from various U.S. dental schools with diverse backgrounds to develop a curriculum framework. The curriculum framework was used in the development of a joint competency statement using an iterative, online consensus process of debate and feedback. RESULTS: The preliminary survey helped frame the initiative and identify potential educational needs and gaps. Consensus was achieved for a recommended competency statement: "Graduates must be competent in promoting oral health through risk assessment, diagnosis, prevention, and management of the hard tissue, soft tissue, and prostheses, and as part of professional recall and home maintenance." This competency statement complements the proposed curriculum framework designed around 3 domains-caries prevention, periodontal supportive care, and prosthesis supportive care-with a set of recommended learning objectives. CONCLUSIONS: Commission on Dental Accreditation (CODA) learning standards do not outline patient-customized, evidence-based recall and home maintenance programs that highlight prevention of dental caries, periodontal supportive care, prosthesis maintenance, and patient education. The proposed competency-based curricular framework serves as an initial step in addressing student learning and patient care within the context of a recall system and home maintenance program while offering schools the needed flexibility for implementation within their curriculum.

Patient-Centered Risk Assessment in Implant Treatment Planning.

PURPOSE: To evaluate the current scientific evidence on estimating cumulative risk for biologic complications relating to dental implants and to develop a patient-centered risk assessment tool for establishing aggregate risk. MATERIALS AND METHODS: A review of the scientific literature on risk indicators relating to dental implants was completed with the goal of identifying and weighting individual risk indicators so aggregate biologic risk could be estimated. Three authors completed independent reviews of the literature, identifying 31 systematic reviews on risk indicators for biologic complications with dental implants, from which 24 potential risk indicators were considered. Due to inconclusive scientific data on risk indicators, a Delphi process was used to gather structured expert opinion to supplement findings from the literature. Eleven Delphi participants with expertise in prosthodontics or periodontics participated in two email exchanges and one face-to-face meeting to comment and debate on the initial identification and weighting of risk indicators, propose the addition or removal of risk indicators, and provide recommended clinical management for each risk indicator. RESULTS: After three rounds of debate, literature review, and additions and removals of various risk indicators, consensus (defined as 95% or more in agreement) was achieved on 20 risk indicators. The Delphi group concluded that the risk indicators of smoking, diabetes, antiresorptive agents, and cemented restorations should include subcategories to more accurately identify and represent patient-specific risk. Clinical recommendations based on individual and aggregate risk were established by consensus. CONCLUSION: The literature on risk indicators for biologic complications was conflicting and inconclusive. The Delphi method was used to identify and establish the weighting of individual risk indicators, resulting in a risk assessment tool for estimating aggregate risk.

Cross-polarization reflectance imaging of root caries and dental calculus on extracted teeth at wavelengths from 400 to 2350 nm.

The identification of root caries and calculus on tooth roots is of increasing importance with our aging population. Exposed root surfaces are often impacted by erosion, abrasion, calculus and staining which can make the identification and management of caries challenging. Identification of dental calculus on root surfaces and verification of its removal is also important for patient education and to decrease susceptibility to caries and periodontal disease. The objective of this study was to determine how the contrast of root caries lesions and dental calculus varies with wavelength in the visible to near-infrared. The contrast of suspected root caries lesions and dental calculus on 30 extracted teeth was measured using cross-polarization reflectance measurements at wavelengths from 400 to 2350 nm. Significantly higher (P < 0.05) lesion contrast was measured at wavelengths greater than 1460 nm. Stains interfered significantly at wavelengths less than 850 nm yielding non-diagnostic contrast for root caries lesions. We postulate that the high absorption of water at longer wavelengths reduced the light scattering from the surrounding and underlying normal dentin, thus increasing the lesion contrast. This study indicates that wavelengths beyond 1400 nm are advantageous for imaging calculus and caries lesions on root surfaces due to the high contrast and lack of interference from stain.

Multispectral near-infrared reflectance and transillumination imaging of occlusal carious lesions: Variation in lesion contrast with lesion depth.

In vivo and in vitro studies have demonstrated that near-infrared (NIR) light at λ=1300-1700-nm can be used to acquire high contrast images of enamel demineralization without interference of stains. The objective of this study was to determine if a relationship exists between the NIR image contrast of occlusal lesions and the depth of the lesion. Extracted teeth with varying amounts of natural occlusal decay were measured using a multispectral-multimodal NIR imaging system which captures λ=1300-nm occlusal transillumination, and λ=1500-1700-nm cross-polarized reflectance images. Image analysis software was used to calculate the lesion contrast detected in both images from matched positions of each imaging modality. Samples were serially sectioned across the lesion with a precision saw, and polarized light microscopy was used to measure the respective lesion depth relative to the dentinoenamel junction. Lesion contrast measured from NIR cross-polarized reflectance images positively correlated (p<0.05) with increasing lesion depth and a statistically significant difference between inner enamel and dentin lesions was observed. The lateral width of pit and fissures lesions measured in both NIR cross-polarized reflectance and NIR transillumination positively correlated with lesion depth.