Effect of zirconia surface conditioning before glazing on the wear of opposing enamel: an in vitro study.

OBJECTIVES: This in vitro study aimed to evaluate the wear of natural teeth opposing 3 mol% yttria-stabilized tetragonal zirconia polycrystal (3Y-TZP) with different surface conditions. MATERIALS AND METHODS: Sixty 3Y-TZP specimens were randomly assigned to six groups (n = 10), differing in surface condition. In three groups, the samples underwent glazing-with the glaze applied to roughened (i.e., 106-µm-grit diamond-finished), as-sintered, and polished zirconia. The three remaining groups consisted of unglazed specimens: solely polished samples and diamond-finished samples (106-µm-grit and 46-µm-grit) without further conditioning. Two-body wear was evaluated at extracted, non-carious molars (n = 60), which served as antagonists in chewing simulation (10,000 masticatory cycles, 49N load). As a control, natural teeth with intact enamel surfaces were tested against natural molars (n = 10). All samples were 3D-scanned before and after the chewing simulation (7 Series, Straumann). Volume loss was calculated (Inspect Software, GOM), and statistically analyzed (SPSS Statistics 24, IBM). RESULTS: Volume loss of the natural antagonists decreased in the following order: 106-µm-grit diamond-finished zirconia (4.6 ± 2.5 mm3), glazed 106-µm-grit diamond-finished zirconia (3.8 ± 1.1 mm3), glazed as-sintered zirconia (3.5 ± 0.9 mm3), 46-µm-grit diamond-finished zirconia (1.7 ± 0.6 mm3), control (1.6 ± 0.7 mm3), glazed polished zirconia (1.4 ± 0.5 mm3), and solely polishing (0.4 ± 0.2 mm3). Even when polishing the surfaces before glazing, volume loss was not mitigated to the same extent as after polishing alone. CONCLUSIONS: The zirconia surface condition beneath the glazing influences antagonist wear. Although polishing before glazing resulted in acceptable levels of antagonist wear, this approach did not yield as favorable results as polishing alone. CLINICAL RELEVANCE: For operators favoring glazing, pre-polishing the zirconia surface could be advantageous to reduce wear.

Cleansing efficacy of an oral irrigator with microburst technology in orthodontic patients-a randomized-controlled crossover study.

OBJECTIVES: Orthodontic patients struggle with interdental cleaning calling for simpler mechanical devices to reduce the high plaque levels. The present study aimed to compare the cleansing efficacy of an oral irrigator with that of dental flossing in patients with fixed braces after 4 weeks of home-use. MATERIALS AND METHODS: The study design is a randomized and single-blinded cross-over study. After 28 days using the products at home, hygiene indices (Rustogi Modified Navy Plaque Index (RMNPI); gingival bleeding index (GBI)) were compared between test (oral irrigator) and control product (dental floss). RESULTS: Seventeen adult individuals finalized the study. After 28 days of cleaning with the oral irrigator, RMNPI was 54.96% (46.91-66.05) compared to 52.98% (42.75-65.60) with dental floss (p = 0.029). Subgroup analysis revealed that the higher cleansing efficacy of the dental floss is attributable to buccal and marginal areas. GBI after the test phase with the oral irrigator was 12.96% (7.14-24.31) and statistically significantly higher compared to 8.33% (5.84-15.33) with dental floss (p = 0.030) which could be seen in all subgroups. CONCLUSIONS: Oral irrigators do not remove plaque and reduce gingival bleeding as efficiently as dental floss in easily accessible regions. However, in posterior regions, where the patients struggled with the application of dental floss, the oral irrigator showed similar results. CLINICAL RELEVANCE: Oral irrigators should only be recommended to orthodontic patients who cannot use interdental brushes and are not compliant with dental flossing.

Cleansing efficacy of an auto-cleaning toothbrushing device with nylon bristles: a randomized-controlled pilot study.

OBJECTIVES: To compare the cleansing efficacy of an auto-cleaning device with nylon bristles (Y-brush®) to that of manual toothbrushing. MATERIALS AND METHODS: Twenty probands refrained from oral hygiene for 3 days. Rustogi Modified Navy Plaque Index was assessed before and after (randomized) toothbrushing either with the auto-cleaning device for 5 s per jaw or with a manual toothbrush for a freely chosen time up to 4 min. The clinical investigation was repeated in a cross-over design. In a third trial period, the brushing time for auto-cleaning was increased to 15 s per jaw. The study was supplemented by plaster cast analyses. RESULTS: Full-mouth plaque reduction was higher with manual toothbrushing than with auto-cleaning for 5 s per jaw (p < 0.001). There was no statistically significant difference on smooth tooth surfaces but on marginal and interdental sites. Increasing the brushing time of auto-cleaning to 15 s per jaw resulted in a comparable full-mouth plaque reduction as with manual toothbrushing (p = 0.177). In 95% of individuals, the device was too short not completely covering second molars. In 30.67% of teeth, the gingival margin was not covered by bristles. CONCLUSIONS: Auto-cleaning devices with nylon bristles have a future potential to reach plaque reduction levels comparable to manual toothbrushing, although manufacturers must focus on improving an accurate fit. CLINICAL RELEVANCE: Under the premise of an ameliorated fit, the auto-cleaning device might be recommendable for people with low brushing efficacy. Interdental sites remain a failure point if adjunct interdental cleaning is not viable.

Dental Students' Oral Health-Related Quality of Life and Temporomandibular Dysfunction-Self-Rating versus Clinical Assessment.

The aim of this study was to compare dental students' self-perception of oral health with the results of a clinical examination of the masticatory system. Seventy-four dental students (38 (51.4%) females and 36 (48.6%) males) completed the Oral Health Impact Profile questionnaire (OHIP-G-14) and underwent a clinical examination according to the Graz Dysfunction Index (GDI). Data were analyzed with descriptive and comparative statistics. Median OHIP-G-14 scores were 3 (IQR 0-6) in the total collective, 4 (1-11) in females, and 2 (0-4) in males (p = 0.072). A score of 0 was found in 29.7% of the sample. The results of the GDI were 50% "normal function", 43.2% "adaptation", 5.4% "compensation", and 1.4% "dysfunction". The comparison of OHIP-G-14 scores and DGI groups showed a significant difference (p = 0.031). Based on the questionnaire, less than one third of the sample indicated maximum oral health-related quality of life. In contrast, the GDI revealed "normal function" or "adaptation" in 93.2%. Dental students underappreciated their oral health condition. Health assessments should not be solely questionnaire-based, especially in health professionals (-to-be). To establish a valid diagnosis of the state of health, self-assessment must be complemented by an objective clinical examination, e.g., GDI.

Medical Diagnoses, Mode of Residence, and Dental Treatment Demand under General Anesthesia in Special Needs Adults in Innsbruck, Austria. A Retrospective Breakdown of Four and a Half Years.

Regarding oral/dental care and attendance, special needs individuals depend on their caregivers' commitment. The purpose of this retrospective data analysis of adults who received dental general anesthesia (DGA) in Innsbruck, Austria, was a breakdown of demographic parameters (including the mode of accommodation/care), medical diagnoses (comprising intellectual/physical disablement (IPD) or psychiatric (anxiety) disorders (PDs)), and dental therapy performed under DGA. The sample was composed of 233 consecutive adults who underwent DGA from January 2015 to June 2019. Data were analyzed with descriptive and comparative statistics. In total, 133 (57.1%) subjects were male and 100 (42.9%) female; 176 (75.5%) had IPD and 57 (24.5%) PDs; 168 (72.1%) were living at private and 65 (27.9%) at nursing homes. Median age (IQR) was 35.6 (25.7-47.2) years. In the total sample, 5 (2-9) teeth were restored and 2 (0.5-6.5) teeth were extracted. Individuals with PDs had more teeth restored (p = 0.01) and extracted (p < 0.001) than individuals with IPD. Private home residents had more teeth restored (p < 0.001) but less teeth extracted (p = 0.003) than nursing home residents. Special needs individuals' oral health backlog should be tackled in private and institutional care modalities alike.

Personality traits and body image in adults with oral piercing: a questionnaire analysis.

OBJECTIVES: Due to the growing popularity of body modifications, dental practitioners are increasingly confronted with oral piercing and its implications. Successful consultation and subsequent change of patient behavior require an understanding of the patient's personality and the deep reasons that explain this self-injurious behavior. This is the first study evaluating personality traits and aspects of body perception in a cohort of adults with oral piercing. METHOD AND MATERIALS: Sixty-two individuals with labial and/or tongue piercing completed three validated questionnaires assessing body perception and personality traits (Questionnaire for assessing one's own body; Sensation Seeking Scale; Big Five Inventory Scale). Fisher Exact probability test and Mann-Whitney U test were used to determine differences in frequency data and in psychologic parameters between subgroups. RESULTS: Eighteen single- and 44 multiple-pierced individuals completed the study (53 women, 9 men). The odds for being multiple pierced was significantly higher for tongue than for labial piercing (3.89 and 0.63, respectively; P = .003). In all psychologic parameters measured, the sample showed score distributions within reference norms. However, multiple-pierced individuals displayed a significantly lesser feeling of attractiveness, less self-confidence, and more uncertainty/anxiety towards their body than single-pierced probands (P < .05). CONCLUSION: Psychologic characteristics of individuals with oral piercing do not fundamentally differ from those of the average population. Therefore, dental practitioners should focus on the medical and dental implications of oral piercing in the counseling of patients who have or intend to have such done.

Zirconia Primers Improve the Shear Bond Strength of Dental Zirconia.

PURPOSE: Various resin cements and priming agents are available for adhesive luting of zirconia restorations. The purpose of this study was to investigate how cement type and priming protocol affect the shear bond strength on zirconia ceramics. MATERIALS AND METHODS: Yttria-stabilized tetragonal zirconia polycrystalline ceramic cylinders were bonded to flat zirconia ceramic surfaces using 7 commercially available resin cements. Ten specimens of each cement group were pretreated with a universal primer, and 10 specimens per group were bonded without pretreatment. In addition, 10 specimens per group were pretreated with system-specific zirconia primers, which were available for 3 cements. Altogether, 170 bonded specimens were water-stored, thermal-cycled, and then submitted to shear bond strength tests. The shear bond strength and the fracture types were documented. Differences in shear bond strengths were assessed using 2-way ANOVA with post-hoc test (α = 0.05). A point-biserial correlation was run between the fracture patterns and the shear bond strengths. RESULTS: The mean shear bond strengths of cements in the unprimed group showed large variations between 2.52 ± 3.01 (mean ± SD) MPa and 33.15 ± 7.35 MPa. Pretreating the specimens with a universal primer improved the shear bond strengths significantly in all groups (p < 0.05) with a range of 21.80 ± 12.51 to 57.20 ± 11.40 MPa. The system-specific primers also improved the shear bond strength significantly, compared to the unprimed group (p < 0.01); however, only one system-specific primer achieved a shear bond strength superior to the universal primer (p < 0.01). There was also a statistical correlation between the fracture type and the shear bond strength (p < 0.0005), with cohesively fractured specimens showing higher shear bond strengths (37.24 ± 19.87 MPa) than adhesively fractured specimens (23.10 ± 17.65 MPa) (p < 0.001). CONCLUSION: Using universal primer can enhance the maximal shear bond strength of zirconia.

Cleansing efficacy of waist-shaped inter-dental brushes. A randomized-controlled crossover study.

OBJECTIVE: To compare the cleansing efficacy of waist-shaped versus cylindric inter-dental brushes in patients receiving supportive periodontal therapy. MATERIALS AND METHODS: After sample size estimation, 20 periodontal maintenance patients diagnosed with periodontitis stage 3 were recruited. Brushing efficacy of waist-shaped and cylindric inter-dental brushes was evaluated in a randomized-controlled, examiner-blinded, two-period crossover study by assessment of the Turesky modification of Quigley-Hein plaque index (T-QHI) and the papillary bleeding index (PBI) at four sites per tooth. RESULTS: Seventeen probands with 1,474 tooth sites finished the study. At baseline, median of overall T-QHI scores was 1.4 (interquartile range 1.38-1.92). After 1 month, T-QHI for waist-shaped inter-dental brushes was 1.24 (1.03-1.52); in 15 individuals, T-QHI 0 was the grade most often measured. T-QHI for cylindric brushes was 1.71 (1.18-2.29; p = .042), with T-QHI 0 being the grade most often measured only in seven individuals. The odds ratio for establishing plaque-free inter-dental sites with waist-shaped relative to cylindric brushes was 1.8 [95% CI 1.6-1.9] (p < .001; logistic regression analysis). There were no statistically significant differences between PBI levels of waist-shaped and cylindric brushes. CONCLUSION: This study has demonstrated the superiority in cleansing efficacy of waist-shaped over cylindric inter-dental brushes in individuals receiving supportive periodontal treatment.

Is it safe to drive after oral surgery?

OBJECTIVES: Driving ability largely depends on the total brake response time (TBRT) corresponding to the time a subject needs to react to a stimulus and apply a well-defined force on the brake pedal. As yet, the English literature completely lacks clinical studies evaluating the TBRT following oral surgery. MATERIALS AND METHODS: In this case-control study, a driving simulator was used to evaluate the TBRT in patients scheduled for oral surgery in local anesthesia. Measurements were taken shortly before (t1) and after (t2) surgery as well as 7-10 days later (t3) when sutures were removed. Results were compared to data of a group of healthy volunteers. RESULTS: Seventy-three patients (37 women, 36 men) underwent evaluation at t1, t2, and t3. In 13 patients who did not return for removal of sutures, only measurements at t1 and t2 could be performed. The median TBRT was 583 milliseconds (ms), 634 ms, and 520 ms at t1, t2, and t3, respectively. Statistical analysis revealed significant differences between readings at t1 versus t2 (t = - 4.944, p < 0.001), t1 versus t3 (t = 7.454, p < 0.001), and t2 versus t3 (t = 11.971, p < 0.001). There was no significant difference between TBRT at t3 in study subjects compared to normal reference values of 67 healthy volunteers. TBRT was significantly increased immediately after oral surgery (t2) compared to measurements 7-10 days postoperatively (t3). Since readings at t3 did not differ from TBRT values in the comparison group, they were considered normal. CONCLUSIONS: Due to significantly elevated total brake response time, driving ability is assumed to be considerably affected following oral surgery, and patients should be advised to abstain from driving immediately after such operations. CLINICAL RELEVANCE: Our study results put into question patients' driving ability following dentoalveolar procedures which should be considered regarding informed consent and could potentially have consequences on health issues (road traffic accidents) as well as legal and financial matters (court charges, insurance claims).

Effect of Dentin Bonding Agents, Various Resin Composites and Curing Modes on Bond Strength to Human Dentin.

This study investigated the influence of several dentin bonding agents, resin composites and curing modes on push-out bond strength to human dentin. 360 extracted caries-free third molars were prepared, cut into slices, embedded in epoxy resin and perforated centrally. One half of the specimens (180) were treated by using one-step adhesive systems and the other half (180) with multi-step adhesive systems. Subsequently, the cavities were filled with either universal, flowable or bulk-fill resin composite according to the manufactures' product line and cured with either turbo or soft start program. After storage the push-out test was performed. The data was analyzed using Kolmogorov-Smirnov, three- and one-way ANOVA followed by the Scheffé post-hoc test, unpaired two-sample t-test (p < 0.05). The strongest influence on push-out bond strength was exerted by the resin composite type (partial eta squared ηP2 = 0.505, p < 0.001), followed by the adhesive system (ηP2 = 0.138, p < 0.001), while the choice of the curing intensity was not significant (p = 0.465). The effect of the binary or ternary combinations of the three parameters was significant for the combinations resin composite type coupled adhesive system (ηP2 = 0.054, p < 0.001), only. The flowable resin composites showed predominantly mixed, while the universal and bulk-fill resin composite showed adhesive failure types. Cohesive failure types were not observed in any group. Multi-step adhesive systems are preferable to one-step adhesive systems due to their higher bond strength to dentin. Flowable resin composites showed the highest bond strength and should become more important as restoration material especially in cavity lining. The use of a soft start modus for polymerization of resin composites does not enhance the bond strength to dentin.

Dental treatment under general anesthesia in adults with special needs at the University Hospital of Dental Prosthetics and Restorative Dentistry of Innsbruck, Austria: a retrospective study of 12 years.

OBJECTIVES: Special needs patients are prone to insufficient oral care and subsequent caries or periodontitis. The aim of this retrospective study was the assessment of demand for restorative therapy and tooth extractions under general anesthesia in adults with intellectual and/or physical disablement (IPD) or psychiatric disorders (PDs) with inherent dentist phobia at the University Hospital of Innsbruck with regard to demographic factors. MATERIALS AND METHODS: A total of 444 consecutive cases of scheduled dental general anesthesia (DGA) in adults from 2003 to 2014 were included. From patient files, demographic data, the presence of either IPD or a PD, attested by a mandatory certificate, and restorative therapy and tooth extractions performed under DGA were obtained. Data analysis was carried out by means of descriptive and comparative statistics. RESULTS: Four hundred two cases (mean age 37.5 ± 13.87 years) assigned to 283 individuals with IPD and 42 cases (mean age 36.09 ± 13.03 years) assigned to 39 individuals with PDs arose in the observed period. Patients with PDs required significantly more restorations (in 7.98 ± 5.4 versus 5.34 ± 4.41 teeth; p = 0.002; Mann-Whitney U test) and extractions (of 4.86 ± 4.51 versus 2.6 ± 3.96 teeth; p < 0.001; Mann-Whitney U test) than patients with IPD. CONCLUSIONS: Demand for dental treatment was high in the collective of special needs patients. Oral health status was worse in patients with PDs than in patients suffering IPD. CLINICAL RELEVANCE: While in patients with severe disablement, DGA presents the only treatment option, specific preventive programs should be implemented for patients with minor disablement or dentist phobia. In these patients, alternative approaches should be promoted.

Amalgam tattoo versus melanocytic neoplasm - Differential diagnosis of dark pigmented oral mucosa lesions using infrared spectroscopy.

BACKGROUND: Dark pigmented lesions of the oral mucosa can represent a major diagnostic challenge. A biopsy is usually required to determine the nature of such intraoral discolorations. This study investigates the potential use of infrared spectroscopy for differential diagnosis of amalgam tattoos versus benign or malignant melanocytic neoplasms. MATERIALS AND METHODS: For this retrospective study, formalin-fixed paraffin-embedded tissue (FFPE) specimens of dark pigmented lesions concerning the oral mucosa or the lip were investigated using mid infrared spectroscopy. The samples were chosen from patients who had undergone a mucosal biopsy at the University Hospital Innsbruck (Austria) between the years 2000 and 2017. Principal component analysis was used for data exploration. Evaluation was based on the superimposition of the recorded spectra and the corresponding histologic slides. RESULTS: In total, 22 FFPE specimens were analyzed. Clear differences were found between amalgam and non-amalgam samples. A general weakening of the penetrating infrared radiation allowed for unspecific discrimination between these two classes. An overall accuracy in predicting the correct class of 95.24% was achieved. CONCLUSION: Infrared spectroscopy appears to be a suitable technique to differentiate between amalgam tattoos and melanocytic lesions in FFPE samples. It could potentially be applied in vivo, too, serving as a non-invasive diagnostic tool for intraoral dark pigmented lesions.

Secretoneurin and PE-11 immunoreactivity in the human dental pulp.

OBJECTIVE: To explore whether there are differences in the concentration of the secretogranin II-derived peptide secretoneurin and the chromogranin B-derived peptide PE-11 between the healthy and inflamed human dental pulps. Furthermore, colocalization studies with calcitonin gene-related peptide were performed to confirm the sensory origin of the peptidergic nerves in the dental pulp. DESIGN: The concentrations of secretoneurin and PE-11 were determined by highly sensitive radioimmunoassays in extracts of dental pulps, the molecular form of secretoneurin immunoreactivities by RP-HPLC with subsequent radioimmunoassay and colocalization studies with calcitonin gene-related peptide were performed by double immunofluorescence. RESULTS: Only secretoneurin but not PE-11 was detectable by radioimmunoassays whereas nerve fibers could be made visible for both secretoneurin and PE-11. Furthermore, there was a full colocalization of secretoneurin and PE-11 with calcitonin gene-related peptide in immunohistochemical experiments. There were no differences in the concentration of secretoneurin between the healthy and inflamed human dental pulp and moreover, the characterization of the secretoneurin immunoreactivities revealed that only authentic secretoneurin was detected with the secretoneurin antibody. CONCLUSIONS: There is unequivocal evidence that secretoneurin and PE-11 are constituents of the sensory innervation of the human dental pulp and although not exclusively but are yet present in unmyelinated C-fibers which transmit predominantly nociceptive impulses. Secretoneurin might be involved in local effector functions as well, particularly in neurogenic inflammation, given that this is the case despite of unaltered levels in inflamed tissue.

Adjusting dental ceramics: An in vitro evaluation of the ability of various ceramic polishing kits to mimic glazed dental ceramic surface.

STATEMENT OF PROBLEM: During the insertion appointment, the practitioner is often faced with the need to adjust ceramic surfaces to fit a restoration to the adjacent or opposing dentition and soft tissues. PURPOSE: The purpose of this study was to assess the ceramic surface smoothness achieved with various commercially available ceramic polishing kits on different commonly used ceramic systems. The reliability of the cost of a polishing kit as an indicator of improved surface smoothness was assessed. MATERIAL AND METHODS: A total of 350 ceramic surfaces representing 5 commonly available ceramic systems (IPS Empress Esthetic, IPS e.max Press, Cergo Kiss, Vita PM 9, Imagine PressX) were treated with 5 types of ceramic polishing systems (Cerapreshine, 94006C, Ceramiste, Optrafine, Zenostar) by following the manufacturers' guidelines. The surface roughness was measured with a profilometer (Taylor Hobson; Precision Taylor Hobson Ltd). The effects of ceramic systems and polishing kits of interest on surface roughness were analyzed by 2-way ANOVA, paired t test, and Bonferroni corrected significance level. RESULTS: The ceramic systems and polishing kits statistically affected surface roughness (P<.001).The polishing kit Zenostar on IPS e.max Press created the smoothest ceramic surface. No correlation could be established between the high cost of the polishing kit and low surface roughness. None of the commonly used ceramic polishing kits could create a surface smoother than that of glazed ceramic (P<.001). CONCLUSIONS: The inclusion of a diamond polishing paste step is recommended to improve surface smoothness (P<.001). The cost of ceramic polishing kits is not recommended as a reliable indicator of better performance of ceramic polishing kits (P>.30).