This report identifies the top cited papers in the field of periodontal regeneration since inception of the concept. Using the H-classics approach, 132 papers published between 1970 and 2012 were identified, with 230.0 ± 175.6 (mean ± SD) citations and 10.4 ± 11.5 citations/year. There were 46 clinical reports, 28 animal studies, 23 in vitro studies, 30 reviews, 3 systematic reviews, and 2 combined animal and in vitro studies. Analysis of covariance showed that institution number (≥3, P = 0.011), journal impact factor at publication (>3.0, P = 0.001) and study type (in vitro/reviews vs. clinical trials/animal studies, P = 0.024) were significantly associated with citations/year. This study has characterized the most influential literature in the field of periodontal regeneration and serves as a quick reference resource.
Remimazolam is a new ultrashort-acting benzodiazepine with fast onset, quick recovery, and few side effects, such as hypotension and respiratory depression. It is expected to be safe and effective for a wide range of patients undergoing intravenous sedation for dental procedures. The aim of this literature review was to evaluate clinical and sedation outcomes for remimazolam, including method of administration, level of sedation at the dose required, and clinical adverse events. An electronic literature search of databases was conducted, and eight articles were selected for inclusion in this review. Onset time from drug administration to optimal sedation level was faster for remimazolam (around 1.5-6.4 min) than for midazolam. Recovery time was significantly shorter for remimazolam than for midazolam and propofol. A study comparing various doses of remimazolam with midazolam found no significant difference in safety. Comparison of a remimazolam group with a propofol group showed that incidences of hypotension (13.0% vs 42.9%, respectively) and respiratory depression (1.1% vs 6.9%, respectively) were significantly lower for remimazolam. Remimazolam appears to be an ideal sedative.
Abstract: This narrative review aims to provide an overview of recent studies and case reports on three-dimensional (3D) printing, and to verify the applicability of 3D printers in the field of dental prostheses. This review was performed by conducting a search of PubMed. The clinical application of fabricating a prosthesis made with cobalt-chromium is considered possible depending on the material and hardware of the 3D printer. However, it is currently difficult to assess the clinical use of 3D-printed zirconia crowns. Further research is required, such as verification of materials used, margin morphology, and hardware. Clinically acceptable results have been reported for patterns using 3D printers. Interim restorations made using a 3D printer have been reported with good results that are considered clinically usable. Dentures made with 3D printers need further verification in terms of strength and deformation. Custom trays made with 3D printers are clinically useful, however, issues remain with design time and effort. Although several studies have reported the usefulness of 3D printers, further verification is required since 3D printers are still considered new technology.
A systematic review was carried out to identify if periprocedural administration of systemic antibiotics could decrease risk of medication-related osteonecrosis of the jaws (MRONJ) in patients under antiresorptive and/or biologic agents for teeth extraction. PubMed/MEDLINE and Scopus were systematically searched for case-series with more than 10 patients, retrospective/prospective studies, and trials concerning this issue. Manual searching of references from previous reviews was also carried out. Of 1,512 results, 17 studies were included, focusing on antibiotics for extraction in patients under intravenous bisphosphonates (8 studies), oral bisphosphonates (2 studies), oral and intravenous bisphosphonates (6 studies), and denosumab (1 study), of which 12 performed dental extraction with surgical flap. With no trials found, “quality in prognosis studies” (QUIPS) tool was used to evaluate risk of bias. First-line treatment was 2-3 grams of oral amoxicillin in 76.4% of studies; 300-600 mg of clindamycin was the alternative treatment in 23.5% of studies. Treatment ranged from 3 to 20 days, consisting of 6-7 days in 47% of studies. No microbiologic insight was provided. A significantly higher risk of MRONJ for patients unexposed to antibiotics was provided in one retrospective study. QUIPS tool revealed moderate-high risk of bias. With empirical data from bias-carrying, heterogeneous observational studies, the validity of antibiotics is yet to be established.
Purpose: This study assessed radiopacity of resin-based computer-aided-design/computer-aided-manufacturing (CAD/CAM) materials by areal grayscale pixel value measurement.
Methods: Radiopacities of six resin-based CAD/CAM block materials and resin composite were evaluated and compared to that of enamel and dentin. Specimens of 1-mm thickness were placed on photostimulable phosphor plate and irradiated with digital x-ray unit. On the radiographic image, regions of interests were determined for each specimen and areal grayscale pixel values were measured. Elemental analysis was performed with energy-dispersive x-ray spectroscopy (EDS) on field emission scanning electron microscope (FESEM) images of the specimens. Data were analyzed statistically (α = 0.05).
Results: Radiopacity values of the restorative materials were significantly different from each other (P < 0.05). Radiopacity values of two resin-based CAD/CAM materials were significantly lower than that of dentin (P < 0.05). All tested restorative materials contain zirconium, three materials contain barium, and only resin composite contains lanthanum.
Conclusion: Four CAD/CAM materials with higher amounts of zirconia or barium (>18%) had radiopacity values significantly higher than the dentin; while two materials with lower amounts of zirconia (<4%) and/or no-barium, had radiopacity values significantly lower than the dentin. EDS analysis suggests materials containing elements with higher atom numbers such as zirconia and barium could exhibit higher radiopacity.
Purpose: To investigate the factors influencing patients’ willingness to replace removable dentures using structural equation modeling (SEM).
Methods: A total of 153 patients who sought consultations for removable dentures self-evaluated denture quality using a visual analog scale (VAS); health-related quality of life using the 36-item Short-Form Health Survey; and oral health-related quality of life using the Oral Health Impact Profile. Dental clinicians evaluated denture quality using a VAS and by assessing the presence of defects. After being informed of various treatments, patients were asked whether they would prefer denture replacement. SEM was applied to analyze the relationships and interactive effects among the variables.
Results: The final model showed high goodness-of-fit indices (chi-square/degree of freedom = 1.009, comparative fit index = 1.000, Tucker-Lewis index = 0.999, standardized root mean square residual = 0.421, and root mean square error of approximation = 0.008). SEM demonstrated that two latent constructs indirectly predicted patients’ willingness to replace dentures; the standardized total effects of good oral health and poor denture quality were −0.154 and 0.503, respectively.
Conclusion: These findings provide a unified understanding of the shared decision-making process for denture replacement and highlight the pretreatment assessments that play a relevant role in patient treatment preferences.
Purpose: This study aimed to clarify the positional relationship between the crown contour and pulp chamber of protostylids using three-dimensional reconstructed images.
Methods: Fourteen molars with protostylids from Japanese subjects were subjected to micro-computed tomography. The external surface configurations of the teeth and pulp chambers were reconstructed. Hard tissue thicknesses in appointed buccal areas were measured on the reconstructed images.
Results: Well-developed protostylids exhibited pulp-prominences above or at the cervical line level. Those that were moderately developed exhibited bulges of the pulp chamber subjacent to the protostylids. Ten of the 14 teeth had prominences in the crown pulp above or at the cervical line level. In addition, 13 teeth exhibited pulp chamber bulges surrounding the lower tooth trunk. No significant differences were apparent in the buccal horizontal thickness of the hard tissue between the protostylids with pulp chamber prominences and the protostylids without pulp chamber prominences at the cervical line level.
Conclusion: Pulp chamber configurations subjacent to protostylids vary based on the development of the traits of the protostylids. Minimum possible taper should be applied during standard vital tooth preparations, as reduced residual dentin thickness is predicted in well- and moderately developed protostylids.
Purpose: The present study aimed to evaluate the effects of zinc deprivation on the properties of membrane and spike-discharge features of mesencephalic trigeminal neurons (MTNs), which are important sensory neurons for oral-motor reflexes and rhythmical jaw movements.
Methods: Neonatal Sprague Dawley rats (P10-12) were distributed equally into a normal diet group and a zinc-deficient diet (ZD) group. Whole cell patch-clamp recordings were obtained from MTNs from coronal brain slices.
Results: Passive membrane properties showed a modest depolarized membrane potential and decreased cell capacitance in the ZD group. Zinc deprivation decreased the minimal current amplitude, which induced an action potential and increased the amplitude of afterhyperpolarization following the action potential. Negligible changes were observed for other action potential properties. A decreased burst duration was observed, accompanied by hastened spike frequency adaptation in the burst discharge. There was no difference in the resonant properties at both the subthreshold depolarized potential and hyperpolarized membrane potential between the control and ZD groups.
Conclusion: These results suggests that neither the persistent sodium conductance nor slow inwardly rectifying conductance were altered; however, there appeared to be an increase in Ca2+-dependent K+ conductance in zincdeficient MTNs.
Purpose: Many studies of tooth dimensions have reported both diversity among populations and sexual dimorphism. This study aimed to collect data on mesiodistal dimensions and sexual dimorphism of permanent teeth of contemporary Western Australian adolescents.
Methods: The mesiodistal dimensions of teeth from 500 adolescents (177 males, 323 females; age, 13-18 years) were obtained from pre-orthodontic treatment digital dental records of examinations using Invisalign technology. Differences between contralateral teeth and sexual dimorphism were analyzed by using SPSS.
Results: Mesiodistal dimensions significantly differed between right and left teeth in both sexes. Males had larger teeth than females, and the difference was significant for most teeth. Reverse dimorphism (females had slightly larger teeth than males) was observed for the maxillary second premolar. Mandibular canines exhibited the greatest dimorphism. In addition, secular trends—specifically, a reduction in the degree of dimorphism—were observed in mesiodistal dimensions.
Conclusion: Mesiodistal dimensions significantly differed between teeth in contralateral quadrants, in both arches. Most teeth exhibited sexual dimorphism, which was the greatest for permanent mandibular canines. Dimorphism was less obvious in this population than in other populations.
Purpose: This study investigated root number and canal configurations, including morphological variations, of mandibular first molars in a subpopulation of South Africans.
Methods: Two calibrated examiners retrospectively evaluated 371 mandibular first molars by using high-resolution cone-beam CT images and the Vertucci classification system with the additions of Sert and Bayirli. Internal and external configurations were recorded, and correlations of sex and age with root number and canal configuration were determined with the chi-square and Fisher exact tests (P < 0.05).
Results: Among mandibular first molars, 0.3% were single-rooted, 98.7% were two-rooted, and 1% were three-rooted. The most frequent configuration was Vertucci Type IV in mesial roots and Vertucci Type I in distal roots. Middle mesial canals were found in 20% and middle-distal canals in 7% of samples. The prevalence of third canals increased in mesial and distal roots as age increased (P > 0.05). Canal configuration and sex were not correlated (P > 0.05).
Conclusion: Mandibular first molars exhibited diverse anatomic characteristics in this subpopulation. Clinicians should be aware of the possibility of additional canals in mandibular first molars, as treatment outcomes may be worse if canals are left untreated.
Purpose: The present study aimed to analyze in a Spanish population sample the compliance of the anterior maxillary teeth to the dental esthetic proportions described in the literature.
Methods: Photographs of the smiles of 78 individuals were calibrated and digitally analyzed considering the following proportions: golden proportion (GP), recurring esthetic dental (RED), golden percentage (GPG), Preston’s proportion and Modified golden percentage (MGPG). For statistical analysis, the t-test of an independent sample was applied, and compliance percentages for each standard were recorded.
Results: The existence of RED 70% or 80% has not been registered. The percentages of compliance with GP were within a range between 0% and 16%. The mean tooth width ratios were adjusted to the values described by Preston (P > 0.05), but the compliance percentages were low (3.33-25%). GPG only presented high percentages of compliance in the lateral incisors (53.33-62.5%). MGPG showed the highest percentages of compliance (50-68%).
Conclusion: After analyzing a Spanish population sample using smile photographs for the first time, GP, RED, GPG and Preston’s proportion standards are not fulfilled and therefore, not suitable for treatments that seek a smile that reproduces natural principles. However, the values designated by MGPG with a deviation of ±1% are largely applicable for treatments that aim for a natural smile.
Purpose: To determine the effects of titanium nanoparticles, that may have been scattered after dental implant placement, on gene and promoter expression, and gingival tissue.
Methods: Ca9-22 cell lines were used as gingival epithelial cells to assess the effects of titanium dioxide nanomaterials as titanium nanoparticles. Cells were cocultured with or without titanium dioxide nanomaterials prior to gene and promoter expression analysis. Expression of interleukin-13α2 receptor was investigated using real-time quantitative reverse-transcription polymerase chain reaction and immunofluorescence staining. Additionally, the enhanced messenger ribonucleic acid (mRNA) expression of transforming growth factor β1 was analyzed using the same method.
Results: Titanium dioxide nanomaterials affected gene and promoter expression in Ca9-22 cells: among the 160 upregulated genes, the upregulation of IL13RA2, which encodes interleukin-13α2 receptor, was the highest (8.625 log2 fold change). Immunofluorescence staining confirmed the increased expression of interleukin-13α2 receptor, which enhanced transforming growth factor β1 expression by stimulation with interleukin-13.
Conclusion: Titanium dioxide nanomaterials applied on the gingival epithelium around the dental implant may increase interleukin-13α2 receptor expression. In turn, this can enhance the secretion of transforming growth factor β1, which is known to promote the differentiation of osteoclasts involved in bone resorption, and potentially affect gingival tissue.
Purpose: The purpose of this study was to examine morphological changes in the superstructure of implants in relation to the degree of attrition of the implant superstructure and its antagonists.
Methods: Thirty-three patients participated. The implant superstructures of the first molar and its antagonists were scanned with an intraoral scanner every 3 months. The amount of attrition was calculated in relation to the various materials used for the superstructure, and differences were analyzed statistically (P < 0.05).
Results: Attrition of the implant superstructure was 110 ± 30 µm for monolithic zirconia and 105 ± 27 µm for resin-veneered metal after 12 months. No statistically significant difference was found between the two groups. In contrast, attrition of the antagonists was 75 ± 25 µm for zirconia and 105 ± 20 µm for resin-veneered metal after 12 months. A statistically significant difference in the attrition levels between the two groups was observed after 9 and 12 months.
Conclusion: During the 12-month observation period, there was no difference in superstructure attrition between zirconia and resin-veneered metal. Attrition of the antagonists was higher for hybrid composite resin-veneered metal than for zirconia, suggesting that surface roughness affected the degree of attrition.
Purpose: The aim of this study was to investigate the stability of orthodontic anchor screws (OASs) in the mid-palatal area according to pre-drilling diameter.
Methods: The success rate of 161 OASs (83 patients, φ2.0 mm, 6.0 mm in length) placed in a corresponding area to the mesial and distal borders of the first molar (mesial zone and distal zone) was assessed according to placement location and pre-drilling diameter (1.2 and 1.5 mm). Placement torque values from 73 OASs with a pre-drilling diameter of 1.2 mm were compared between success and failure groups.
Results: The success rates of OASs pre-drilled with φ1.2 and 1.5 mm were 94.5% and 83.0%, respectively (P < 0.05); corresponding rates in the mesial zone were 100.0% and 77.3% (P < 0.005), and those in the distal zone were 89.2% and 88.6%, respectively. Placement torques of OASs predrilled with φ1.2 mm in the success and failure groups were 25.9 and 19.2 N·cm, respectively (P < 0.05).
Conclusion: A smaller pre-drilling diameter was associated with a higher success rate of OASs in the mid-palatal area, especially in the mesial zone. When pre-drilling diameter of 1.2 mm was used for φ2.0 mm OAS, greater placement torque was indicative of greater OAS stability.
Purpose: To evaluate the influence of polymerization methods and a metal priming agent on the bond strength between gold alloy for metal ceramic restorations and dual-cure-type resin luting agents, and on the strength and hardness of the luting agents.
Methods: A total of 154 disks cast by a gold alloy were treated with or without a metal priming agent. One of the three luting agents was applied on the disk. The luting agent was either chemically or dual-polymerized. The shear bond strength was measured both before and after thermocycling. In addition, scanning electron microscope (SEM) observation, flexural strength test, and Knoop hardness test were performed.
Results: Significant differences among the luting agents were observed in terms of bond strength and flexural strength. Significant differences between chemically and dual-polymerized luting agents were observed regarding shear bond strength, flexural strength, and Knoop hardness before thermocycling. The application of the priming agent was effective only for a luting agent.
Conclusion: Both bond strength and flexural strength differed among three luting agents. The effect of the priming agent on bond strength differed among the luting agents. Both the bond and flexural strength of a chemically polymerized luting agent differed before or after thermocycling.
Blue diode laser emits a 445 nm wavelength light, which is extremely effective with hemoglobin, and has an optimal hemostatic effect. This work analyzes its thermal effects and clinical efficacy, when used to perform excisional biopsies. Forty-two excisional biopsies were performed with the laser; then, the extent of perincisional thermal effects was evaluated and patients were followed up. Average alteration on epithelial tissue was 507.07 µm, and on connective tissue was 320.39 µm. In all the cases, it was possible to obtain a histological diagnosis. Diode lasers can be safely used to perform biopsies; various intra- and postoperative advantages were confirmed.
Abstract: The condyle is the most common site of mandibular fracture. In the present study, an attempt was made to utilize three-dimensional computed tomography (3D-CT) images to evaluate mandibular condyle fractures and identify prognostic indicators of malocclusion after closed treatment. Accurate morphometric measurements were performed using 3D-CT images obtained before trauma, after trauma, and after healing. Morphometry revealed significant differences in loss of ramus height (LRH) and lateral movement length in patients with malocclusion, and significant LRH differences in patients with other maxillomandibular fractures after healing, or in those with dislocation-displacement. The present method of 3D-CT image analysis appears useful for evaluation of condylar fractures.
Despite scientific evidence that root canal debridement is the cornerstone for successful treatment, the effectiveness of a combination of delivery and activation systems in cleaning root canals remains unknown. This study is the first to demonstrate the remaining pulp tissue in root canals after irrigation with various techniques such as positive pressure syringe-and-needle irrigation, ultrasonic activation, negative pressure irrigation and ultrasonic activation after negative pressure irrigation. The results showed that negative pressure irrigation alone and its combination with ultrasonic activation resulted in significantly superior effectiveness than positive pressure irrigation and ultrasonic activation alone in the apical-third of root canals.
This study aimed to determine the appropriate treatment methods and evaluate associated factors by comparing nonoperative treatment alone with a combination of both nonoperative and surgical treatment in 34 patients with mandibular osteoradionecrosis (mORN). The associated cure factors were analyzed by Cox regression. Propensity scores were calculated from factors that were not significant in the univariate analysis and used as covariates in the multivariate analysis. The cure rate among patients who received nonoperative and surgical treatment was higher than that observed with nonoperative treatment alone. Only the treatment method was associated with cure in both univariate and multivariate analyses.
The purpose of this study was to determine if intraoral scanners (IOS) are useful for dental hygiene instruction. The dental plaque of eight volunteers with healthy dentition was stained with a plaque-disclosing solution, and the O’Leary Plaque Control Record (PCR) was measured by direct observation and by evaluating IOS images. PCR values were higher for IOS images than for direct observation. The difference was greatest for the lingual surface of mandibular anterior teeth. Use of IOS for dental plaque examination might be useful as a novel method for dental hygiene instruction.
The aim of this study was to clarify whether hydroxyapatite/collagen composite material (HAp/Col) could be useful as a graft material for maxillary sinus floor augmentation (MSFA). MSFA and implant placement were performed simultaneously. When the lateral approach was employed, 3 out of 19 implants failed in 3 maxillary sinuses (success rate; 84.2%), and in these cases the alveolar bone heights, cortical bone thicknesses and values of the implant stability quotient were smaller. If alveolar the bone height, cortical bone thickness, and healing period are optimized, HAp/Col can be a useful graft material for MSFA.
Backsliding is a major problem when moving the maxilla significantly forward in orthognathic surgery. For example, in sleep surgery, maxillomandibular advancement is an application of orthognathic surgery, and it is well known that the anterior movement of the maxilla back and forth is an important factor that greatly widens the pharyngeal airway. However, postoperative backsliding is a major problem in this surgery. Therefore, a surgical method was devised to prevent the maxilla from retracting by adjusting the bone when moving the maxilla forward.