Clinical and histological wound healing patterns of collagen-based substitutes: An experimental randomized controlled trial in standardized palatal defects in humans.

AIM: To evaluate the progression of wound healing of standardized palatal defects in groups using three different collagen-based wound dressings and a control group, in terms of wound closure, pain perception and descriptive histology. MATERIALS AND METHODS: Twenty participants were enrolled in this experimental study, in whom four palatal defects were created. The defects (6 mm diameter, 3 mm depth) were randomly assigned to one of four treatment modalities: C (control), MG (Mucograft®), MD (mucoderm®) and FG (Fibro-Gide®). Photographs were taken, and pain assessment was performed before and after treatment and at 5, 7, 9, 12, 14 and 16 days after surgery. All participants wore a palatal splint for a duration of 16 days. RESULTS: All groups achieved complete wound closure at 14 days. The percentage of the remaining open wound on day 7 amounted to 49.3% (C; interquartile range [IQR]: 22.6), 70.1% (FG; IQR: 20.7), 56.8% (MD; IQR: 26.3) and 62.2% (MG; IQR: 34.4). Statistically significant differences were found between FG and C (p =.01) and between MD and FG (p =.04). None of the participants rated pain higher than 4 out of 10 during the entire study period. CONCLUSIONS: Collagen-based wound dressings provide coverage of open defects, albeit without acceleration of wound closure or reduction of pain. FG (which is not intended for open oral wounds) showed slower wound closure compared to C and MD.

Accuracy of augmented reality-assisted vs template-guided apicoectomy - an ex vivo comparative study.

AIM: The aim of the present ex vivo study was to examine the accuracy of augmented reality-assisted apicoectomies (AR-A) versus template-guided apicoectomies (TG-A). MATERIALS AND METHODS: In total, 40 apicoectomies were performed in 10 cadaver pig mandibles. Every pig mandible underwent two AR-A and two TG-A in molar and premolar teeth. A crossed experimental design was applied. AR-A was performed using Microsoft HoloLens 2, and TG-A using SMOP software. Postoperative CBCT scans were superimposed with the presurgical planning data. The deviation between the virtually planned apicoectomy and the surgically performed apicoectomy was measured. The primary (angular deviation [degrees]) and secondary (depth deviation [mm]) outcome parameters were measured. RESULTS: Overall, 36 out of 40 apicoectomies could be included in the study. Regarding the primary outcome parameter (angular deviation), there was no significant difference between AR-A and TG-A. The mean values were 5.33 degrees (± 2.96 degrees) in the AR-A group, and 5.23 degrees (± 2.48 degrees) in the TG-A group. The secondary outcome parameter (depth deviation) showed no significant difference between the AR-A group of 0.27 mm (± 2.32 mm) and the TG-A group of 0.90 mm (± 1.84 mm). In this crossed experimental design, both techniques overshot the target depth in posterior sites, as opposed to not reaching the target depth in anterior sites (P < 0.001). CONCLUSION: Augmented reality (AR) technology has the potential to be introduced into apicoectomy surgery in case further development is implemented.

Buccal soft tissue dehiscence defects at dental implants-associated factors and frequency of occurrence: A systematic review and meta-analysis.

AIM: To identify the factors associated with buccal peri-implant soft tissue dehiscences (BSTDs) and their frequency of occurrence. MATERIALS AND METHODS: Randomized controlled trials, controlled clinical trials, cohort studies, and case series assessing the frequency of occurrence of BSTD were included. BSTD was defined as an apical migration of the peri-implant soft tissues of ≥1 mm from the baseline examination (final restoration) or in comparison with the adjacent or contralateral natural tooth. Frequency distributions of BSTD related to the presence or absence of any surgical, prosthetic, or anatomic factor that may have contributed to the development of BSTD were recorded. Random-effects meta-analyses using odds ratios (OR) were performed to investigate the association of certain factors with the development of BSTD. RESULTS: Twenty-four articles were finally included belonging to 22 clinical investigations. Patients at higher risk of developing BSTD were associated with thin biotype (OR = 2.85 [1.40, 5.8], n = 5, p = .003) and with buccally placed implants (OR = 14.37 [4.58, 45.14], n = 3, p ≤ .001). Patients without connective tissue grafting (CTG) had greater odds of developing BSTD (OR = 9.00 [3.11, 26.02], n = 5, p ≤ .001), while buccal bone plate thickness of <1 mm and immediately placed implants were not associated with greater BSTD (OR = 1.29 [0.35, 4.77], n = 2, p = .704 and OR = 1.56 [0.46, 5.26], n = 4, p = .477, respectively). The frequency of occurrence of BSTD varied across the included studies with a range from 0% to 61%. CONCLUSIONS: Thin tissue biotype and buccally placed implants were associated with BSTD, whereas CTG seemed to have a protective effect. Thin buccal plates and immediately placed implants did not demonstrate a higher risk of BSTD.

Clinical outcomes of all-ceramic single crowns and fixed dental prostheses supported by ceramic implants: A systematic review and meta-analyses.

OBJECTIVE: To analyze the clinical outcomes of all-ceramic single crowns (SCs) and fixed dental prostheses (FDPs) supported by ceramic implants. MATERIALS AND METHODS: Based on a focused question and customized PICO framework, electronic (Medline/EMBASE/Cochrane) and manual searches for studies reporting the clinical outcomes of all-ceramic SCs and FDPs supported by ceramic implants ≥12 months were performed. The primary outcomes were reconstruction survival and the chipping proportion. The secondary outcomes were implant survival, technical complications, and patient-related outcome measurements. Meta-analyses were performed after 1, 2, and 5 years using random-effect meta-analyses. RESULTS: Eight of the 1,403 initially screened titles and 55 full texts were included. Five reported on monolithic lithium disilicate (LS2) SCs, one on veneered zirconia SCs, and two on veneered zirconia SCs and FDPs, which reported all on cement-retained reconstructions (mean observation: 12.0-61.0 months). Meta-analyses estimated a 5-year survival rate of 94% (95% confidence interval [CI]: 82%-100%) for overall implant survival. Reconstruction survival proportions after 5 years were: monolithic LS2, 100% (95%CI: 95%-100%); veneered zirconia SCs, 89% (95%CI: 62%-100%); and veneered zirconia FDPs 94% (95%CI: 81%-100%). The chipping proportion after 5 years was: monolithic LS2, 2% (95%CI: 0%-11%); veneered zirconia SCs, 38% (95%CI: 24%-54%); and veneered zirconia FDPs, 57% (95%CI: 38%-76%). Further outcomes were summarized descriptively. CONCLUSIONS: Due to the limited data available, only tendencies could be identified. All-ceramic reconstructions supported by ceramic implants demonstrated promising survival rates after mid-term observation. However, high chipping proportions of veneered zirconia SCs and, particularly, FDPs diminished the overall outcome. Monolithic LS2 demonstrated fewer clinical complications. Monolithic reconstructions could be a valid treatment option for ceramic implants.

Efficacy and safety of P11-4 for the treatment of periodontal defects in dogs.

OBJECTIVES: This study's aim was to investigate the safety and performance of a self-assembling peptide matrix (SAPM) P11-4 for the treatment of periodontal disease in a controlled pre-clinical study. MATERIALS AND METHODS: Acute buccal bony dehiscence defects (LxW: 5 × 3 mm) were surgically created on the distal root of four teeth on one mandible side of 7 beagle dogs followed by another identical surgery 8 weeks later on the contralateral side. SAPM P11-4 (with and without root conditioning with 24% EDTA (T1, T2)), Emdogain® (C) and a sham intervention (S) were randomly applied on the four defects at each time point. Four weeks after the second surgery and treatment, the animals were sacrificed, the mandibles measured by micro-computed tomography (µ-CT) and sections of the tissue were stained and evaluated histologically. RESULTS: Clinically and histologically, no safety concerns or pathological issues due to the treatments were observed in any of the study groups at any time point. All groups showed overall similar results after 4 and 12 weeks of healing regarding new cementum, functionality of newly formed periodontal ligament and recovery of height and volume of the new alveolar bone and mineral density. CONCLUSION: A controlled clinical study in humans should be performed in a next step as no adverse effects or safety issues, which might affect clinical usage of the product, were observed. CLINICAL RELEVANCE: The synthetic SAPM P11-4 may offer an alternative to the animal-derived product Emdogain® in the future.

Accuracy of digital complete-arch, multi-implant scans made in the edentulous jaw with gingival movement simulation: An in vitro study.

STATEMENT OF PROBLEM: The use of computer-aided design and computer-aided manufacturing (CAD-CAM) technologies is widely established, with single restorations or short fixed partial dentures having similar accuracy when generated from digital scans or conventional impressions. However, research on complete-arch scanning of edentulous jaws is sparse. PURPOSE: The purpose of this pilot in vitro study was to compare the accuracy of a digital scan with the conventional method in a workflow generating implant-supported complete-arch prostheses and to establish whether interference from flexible soft tissue segments affects accuracy. MATERIAL AND METHODS: An edentulous maxillary master cast containing 6 angled implant analogs was used and digitized with mounted scan bodies by using a high-precision laboratory scanner. The master cast was then scanned 10 times with 4 different intraoral scanners: TRIOS 3 with a complete-arch scanning strategy (TRI1) or implant-scanning strategy (TRI2), TRIOS Color (TRC), CEREC Omnicam (CER), and CEREC Primescan (PS). The same procedure was repeated with 4 different levels of free gingiva (G0-G3). Ten conventional impressions were obtained. Differences in implant position and direction were evaluated at the implant shoulder as mean values for trueness and interquartile range (IQR) for precision. Statistical analysis was performed by using the Kruskal-Wallis and post hoc Conover tests (α=.05). RESULTS: At G0, position deviations ranged from 34.8 µm (IQR 23.0 µm) (TRC) to 68.3 µm (12.2 µm) (CER). Direction deviations ranged from 0.34 degrees (IQR 0.18 degrees) (conventional) to 0.57 degrees (IQR 0.37 degrees) (TRI2). For digital systems, the position deviation ranged from 48.4 µm (IQR 5.9 µm) (PS) to 76.6 µm (IQR 8.1 µm) (TRC) at G1, from 36.3 µm (IQR 9.3 µm) (PS) to 79.9 µm (IQR 36.1 µm) (TRI1) at G2, and from 51.8 µm (IQR 14.3 µm) (PS) to 257.5 µm (IQR 106.3 µm) (TRC) at G3. The direction deviation ranged from 0.45 degrees (IQR 0.15 degrees) (CER) to 0.64 degrees (IQR 0.20 degrees) (TRC) at G1, from 0.38 degrees (IQR 0.05 degrees) (PS) to 0.925 degrees (IQR 0.09 degrees) (TRI) at G2, and from 0.44 degrees (IQR 0.07 degrees) (PS) to 1.634 degrees (IQR 1.08 degrees) (TRI) at G3. Statistical analysis revealed significant differences among the test groups for position (G0: P<.001; G1: P<.05; G2: P<.001; G3: P<.001) and direction (G0: P<.005; G1: P<.001; G2: P<.001; G3: P<.001). CONCLUSIONS: Without soft tissue interference, the accuracy of certain digital scanning systems was comparable with that of the conventional impression technique. The amount of flexible soft tissue interference affected the accuracy of the digital scans.

Final Posttreatment Occlusion in Patients With Unilateral Cleft Lip and Palate.

OBJECTIVE: To evaluate final posttreatment occlusion in patients with complete unilateral cleft lip and palate (cUCLP) by comparing (1) 3 treatment centers, (2) males and females, (3) cleft and noncleft sides, (4) right- and left-sided clefts, and (5) orthodontic treatment with/without orthognathic surgery (OS). DESIGN: Retrospective cohort study. PATIENTS: Blinded posttreatment dental casts of 56 patients (19.4 ± 1.4 years) with cUCLP from 3 centers in Switzerland. MAIN OUTCOME MEASURE: Occlusal assessment using the modified Huddart/Bodenham (MHB) index. RESULTS: Our sample comprised 35 males and 21 females, 46 with left- and 10 with right-sided clefts, of which 32 had undergone OS. The final posttreatment occlusion showed a median MHB score of 0 (interquartile range: -1.0 to 2.0) in the total sample and did not seem to depend on treatment center, sex, or OS. The MHB scores for the anterior buccal and the buccal segments were more negative on the cleft than on the noncleft side (P = .002 and P = .006, respectively). When the cleft was on the left side, the MHB score tended to be more positive in the labial (P = .046) and anterior buccal segments (P = .034). CONCLUSIONS: This study shows a very satisfactory final posttreatment occlusion in patients with cUCLP. The more constricted buccal occlusion on the cleft side emphasizes the attention that should be given in correcting the more medially positioned lesser maxillary segment. The influence of cleft-sidedness should be analyzed further on a sample including more patients with right-sided clefts.

Evaluation of air polishing with a sterile powder and mechanical debridement during regenerative surgical periimplantitis treatment: a study in dogs.

OBJECTIVES: To evaluate the effectiveness of mechanical debridement and/or air polishing on the healing of ligature-induced buccal periimplantitis dehiscence defects in dogs. MATERIAL AND METHODS: Forty-eight implants were placed in the mandibles of twelve beagle dogs, and periimplantitis was induced for 2 months using ligatures. The resulting buccal dehiscence-type defects were surgically cleaned and augmented (xenogenic filler and resorbable membrane) according to one of the following treatments: (1) Cleaning with carbon curette (debridement - D) and guided bone regeneration (GBR/G): DG, (2) air polishing cleaning (A) and GBR: AG, (3) a combination of D/A/G: DAG, and (4) D/A without GBR: DA. After 2 months, histomorphometric and inflammatory evaluations were conducted. RESULTS: The median bone gain after therapy ranged between 1.2 mm (DG) and 2.7 mm (AG). Relative bone gain was between 39% (DG) and 59% (AG). The lowest inflammation scores were obtained in DA without GBR (5.84), whereas significantly higher values between 8.2 and 9.4 were found in the groups with augmentation. At lingual sites without defects, scores ranged from 4.1 to 5.9. According to ISO, differences above 2.9 were considered representative for irritative properties. CONCLUSIONS: All treatments resulted in partial regeneration of the defects. No treatment group showed a significantly (p < 0.05) better outcome. However, pretreatment with air polishing showed a tendency for less inflammation. Noteworthy, inflammation assessment showed an overall irritative potential after GBR in the evaluated early healing phase. CLINICAL RELEVANCE: Periimplantitis treatment still represents a big issue in daily practice and requires additional preclinical research in order to improve treatment concepts.

Diagnostic Accuracy of Cystic Lesions Using a Pre-Programmed Low-Dose and Standard-Dose Dental Cone-Beam Computed Tomography Protocol: An Ex Vivo Comparison Study.

BACKGROUND: This study aimed to analyze the diagnostic reliability of radiographic assessment of cystic lesions using a pre-set, manufacturer-specific, low-dose mode compared to a standard-dose dental cone-beam computed tomography (CBCT) imaging protocol. METHODS: Forty pig mandible models were prepared with cystic lesions and underwent both CBCT protocols on an Orthophos SL Unit (Dentsply-Sirona, Bensheim, Germany). Qualitative and quantitative analysis of CBCT data was performed by twelve investigators independently in SIDEXIS 4 (Dentsply-Sirona) using a trial-specific digital examination software tool. Thereby, the effect of the two dose types on overall detectability rate, the visibility on a scale of 1 (very low) to 10 (very high) and the difference between measured radiographic and actual lesion size was assessed. RESULTS: Low-dose CBCT imaging showed no significant differences considering detectability (78.8% vs. 81.6%) and visibility (9.16 vs. 9.19) of cystic lesions compared to the standard protocol. Both imaging protocols performed very similarly in lesion size assessment, with an apparent underestimation of the actual size. CONCLUSION: Low-dose protocols providing confidential diagnostic evaluation with an improved benefit-risk ratio according to the ALADA principle could become a promising alternative as a primary diagnostic tool as well as for radiological follow-up in the treatment of cystic lesions.

Potential of different fluoride gels to prevent erosive tooth wear caused by gastroesophageal reflux.

BACKGROUND: This in-vitro-study aimed to evaluate the potential of different fluoride gels to prevent gastroesophageal reflux induced erosive tooth wear. METHODS: Surface baseline profiles of a total of 50 bovine enamel specimens [randomly assigned to five groups (G1-5)] were recorded. All specimens were positioned in a custom made artificial oral cavity and perfused with artificial saliva (0.5 ml/min). Reflux was simulated 11 times a day during 12 h by adding HCl (pH 3.0) for 30 s (flow rate 2 ml/min). During the remaining 12 h (overnight), specimens were stored in artificial saliva and brushed twice a day (morning and evening) with a toothbrush and toothpaste slurry (15 brushing strokes). While specimens in the control group (G1) did not receive any further treatment, specimens in G2-5 were coated with different fluoride gels [Elmex Gelée (G2); Paro Amin Fluor Gelée (G3); Paro Fluor Gelée Natriumfluorid (G4); Sensodyne ProSchmelz Fluorid Gelée (G5)] in the evening for 30 s. After 20 days, surface profiles were recorded again and enamel loss was determined by comparing them with the baseline profiles. The results were statistically analysed using one-way analysis of variance (ANOVA) followed by Tukey`s HSD post-hoc test. RESULTS: The overall highest mean wear of enamel (9.88 ± 1.73 µm) was observed in the control group (G1), where no fluoride gel was applied. It was significantly higher (p < 0.001) compared to all other groups. G2 (5.03 ± 1.43 µm), G3 (5.47 ± 0.63 µm, p = 0.918) and G4 (5.14 ± 0.82 µm, p > 0.999) showed the overall best protection from hydrochloric acid induced erosion. Enamel wear in G5 (6.64 ± 0.86 µm) was significantly higher compared to G2 (p = 0.028) and G4 (p = 0.047). CONCLUSIONS: After 20 days of daily application, all investigated fluoride gels are able to significantly reduce gastroesophageal reflux induced loss of enamel.

Origin of MMP-8 and Lactoferrin levels from gingival crevicular fluid, salivary glands and whole saliva.

BACKGROUND: Pathologically elevated levels of matrix metalloproteinase-8 (MMP-8) and Lactoferrin in oral fluids have been associated with the presence of gingivitis/periodontitis. This study aimed to assess the origin of MMP-8 and Lactoferrin in periodontitis patients and to identify the degree to which conventional clinical parameters correlate with their presence. METHODS: A total of ten periodontitis and ten healthy patients were included in this study. Whole saliva (stimulated and unstimulated), parotid/sublingual glandular fluid and gingival crevicular fluid from pockets and sulci were tested for MMP-8 and Lactoferrin and protein concentrations were quantified using an ELISA assay. Clinical parameters were checked for potential associations with MMP-8 and Lactoferrin levels. RESULTS: Periodontal patients presented higher concentrations of MMP-8 and Lactoferrin in pockets than other sources (P = 0.03). Lactoferrin measurement was higher in the parotid compared to sublingual glandular fluid in periodontitis patients (P = 0.03). Increased probing pocket depth was positively correlated with high MMP-8 and Lactoferrin levels. CONCLUSIONS: Periodontal pockets appear to be the major source of active matrix metalloproteinase and Lactoferrin, which also may also enter the oral cavity through the salivary glands. Since clinically healthy sites in periodontitis patients also had elevated biomarker levels, gingival crevicular fluid biomarker testing may be more predictive of future tissue breakdown than conventional clinical parameters.

Prevention of Enamel Softening by Rinsing with a Calcium Solution before Dental Erosion.

OBJECTIVES: This in situ study aimed to evaluate whether rinsing with a calcium-containing solution prior to an erosive attack reduces the softening of enamel. MATERIALS AND METHODS: A total of 240 bovine enamel samples with determined baseline surface microhardness (KHN) were allocated to 5 runs in which each of the 12 volunteers performed the following experiment: 4 enamel samples were inserted in a custom-made intraoral appliance and carried in the mouth (upper jaw) for 30 min before each volunteer either rinsed his mouth for 60 s with a fluoride- and stannous ion-containing dental erosion protection mouth rinse as positive control (run 1), milk (run 2), a solution prepared from a 500-mg calcium effervescent tablet dissolved in 100 mL (run 3) or 200 mL (run 4) water, or did not perform any rinsing with a test solution before the erosive attack (run 5, negative control). To simulate the erosive attack, volunteers rinsed their mouth with a commercial soft drink (Sprite Zero) for 60 s and afterwards with water to stop the erosive process. Finally, surface microhardness was measured again and hardness loss (ΔKHN) calculated. A mixed effect model was fitted to the data set to investigate whether the different runs showed differences with respect to ΔKHN. RESULTS: No significant difference in softening of enamel (mean of ΔKHN; lower confidence level/upper confidence level) was observed between the negative control run 5 (50.7; 60.8/40.6), run 2 (50.7; 60.8/40.6), run 3 (38.7; 48.8/28.6) and run 4 (40.7; 50.8/30.6) (p > 0.05, respectively). Enamel softening in the positive control run 1 (25.4; 35.6/15.3) was significantly lower compared to the softening in run 5 (p < 0.001). No significant difference was observed between run 1 and run 3 (p = 0.09). CONCLUSION: Other than the fluoride- and stannous ion-containing dental erosion protection mouth rinse, none of the investigated calcium-containing solutions is able to significantly reduce erosion-induced softening of enamel.

Effects of Additional Use of Bioactive Glasses or a Hydroxyapatite Toothpaste on Remineralization of Artificial Lesions in vitro.

OBJECTIVES: This in vitro study aimed to evaluate and compare the effect of two different bioactive glasses, a hydroxyapatite-containing, fluoride-free toothpaste (HTP) and a fluoride toothpaste (FTP) on the remineralization behavior of initial caries lesions. MATERIALS AND METHODS: A total of 100 bovine enamel samples were randomly allocated to five groups of 20 samples each: NC = negative control group (artificial saliva); HTP = HTP group (Karex); FTP = FTP group (Elmex caries protection, 1,400 ppm); FTP + BGnano = FTP followed by Actimins bioactive glass; FTP + BGamorph = FTP followed by Schott bioactive glass. Radiographic documentation (advanced transversal microradiography; aTMR) was applied before and after all samples were exposed to a demineralizing gel for 10 days. Over a period of 28 days, samples were covered twice a day (every 12 h) with a toothpaste slurry of the respective test group or with artificial saliva in NC for 60 s and brushed with 15 brushing strokes. Samples in FTP + BGnano and FTP + BGamorph were additionally treated with the respective bioactive glass slurry for 30 s after brushing with the FTP. In the meantime, all samples were stored in artificial saliva. After 28 days, the structure of all samples was assessed again using aTMR and compared to the values measured after demineralization. The statistical evaluation of the integrated mineral loss was performed using Kruskal-Wallis test followed by a post hoc Conover test. RESULTS: The FTP revealed the significantly highest increase of mineral content while the HTP showed the significantly lowest remineralization. Compared to artificial saliva, the use of the HTP or the combined application of FTP followed by bioactive glasses (FTP + BGnano and FTP + BGamorph) showed no significant remineralization. CONCLUSION: Under remineralizing in vitro conditions, brushing with 1,400 ppm FTP induced significantly more remineralization compared to storage in artificial saliva. The additional administration of both bioactive glasses as well as the substitutional brushing with an HTP resulted in significantly less remineralization compared to brushing with 1,400 ppm FTP.

Improved Results in Closed Reduction of Zygomatic Arch Fractures by the Use of Intraoperative Cone-Beam Computed Tomography Imaging.

PURPOSE: The use of intraoperative imaging could help overcome the insufficiency of closed reduction that can result from the absence of visible feedback to evaluate the accuracy of the reduction in isolated zygomatic arch fractures. The aim of the present study was to evaluate the use of intraoperative 3-dimensional cone-beam computed tomography (CBCT) to improve the accuracy of reduction, by measuring the remaining cortical step and dislocation angle. We also evaluated the effect of CBCT on the need for repeat surgery. PATIENTS AND METHODS: We performed a retrospective cohort study of patients who had undergone zygomatic arch reduction surgery from January 2008 to May 2018. The patients were grouped according to the predictor variables into group A (postoperative radiologic follow-up studies) and group B (intraoperative CBCT imaging studies). The primary outcome variables were the remaining cortical step and dislocation angle compared with the ideal virtually mirrored position. These were assessed as measures of reduction accuracy. The secondary variables included age, gender, surgery duration, and fracture type. Statistical analysis was performed using a robust multiple regression analysis. RESULTS: The 45 patients were divided into 2 subgroups with 18 patients in the no intraoperative imaging (control) group and 27 patients in the intraoperative imaging group. Insufficient reduction occurred in 1 patient in the group without intraoperative imaging, leading to repeat surgery. No repeat surgery was necessary in the intraoperative imaging group. The remaining cortical step of the intraoperative imaging group was significantly lower than that of the control group (0.18 vs 2.03 mm; P < .001). For the remaining dislocation angle, similar findings were observed but without statistical significance (3.93° vs 7.75°; P = .58). CONCLUSIONS: The use of intraoperative CBCT significantly increased the accuracy of the reduction. Furthermore, the need for repeat surgery was not required for any patient in the intraoperative imaging group with CBCT-guided reduction.

Gingival recession after scaling and root planing with or without systemic metronidazole and amoxicillin: a re-review.

BACKGROUND: Gingival recessions inevitably occur during healing after scaling and root planing, but synoptic data on this topic is still lacking. This review compared the recession formation with and without the administration of systemic antibiotics. OBJECTIVES: To evaluate the formation of recession with and without the administration of antibiotics during the healing after scaling and root planing. MATERIALS AND METHODS: This study re-analyzed publications that reported clinical attachment levels (CAL) and probing pocket depths (PD) up to January 2019, including the pivotal review by Zandbergen and co-workers (2013). Whereas these studies traditionally focused on PD and CAL, the present analysis compared recession formation (ΔREC) after adjunctive systemic administration of amoxicillin (amx) and metronidazole (met) during scaling and root planing (SRP) and SRP alone. The mean increase in ΔREC, if not reported, was calculated from CAL and PD values and statistically analyzed. Recession formation was compared after 3 and 6 months after therapy. Results were separately reported for chronic periodontitis (CP) as well as aggressive periodontitis (AP) cases. RESULTS: Recessions increased consistently between baseline and follow-up. In the AP group, median ΔREC was 0.20 mm after 3 months, irrespective of whether antibiotics were administered or not. After 6 months, median ΔREC increased to 0.35 mm after AB and remained stable at 0.20 mm with SRP alone. In the CP group, after 3 months with and without antibiotics, median ΔREC accounted for 0.30 mm and 0.14 mm, respectively. After 6 months, median ΔREC accounted for 0.28 mm (with AB) and 0.20 mm (without AB). The quantitative assessment by meta-analyses also yielded small values (≤ 0.25 mm) for the estimated differences in recession formation between AB and noAB; however, none of them reached statistical significance. CONCLUSIONS: Although a slight tendency towards higher recession formation after SRP in combination with AB could be observed in many studies, quantitative meta-analyses showed no clinically relevant difference in recession formation due to the administration of AB. In general, the description and discussion of recessions in the literature seems not to be a major focus so far. CLINICAL RELEVANCE: Since the preservation of gingival tissues is important by preventive and therapeutic means, e.g., when avoiding postoperative root sensitivity or performing regenerative surgery, these aspects should not be neglected. We thus suggest to report REC measurements along with PD and CAL values for more direct recession formation (ΔREC) assessments in the future.

Mechanical properties of toothpastes with diamond abrasives.

OBJECTIVE: The aim of this study was to evaluate and compare surface roughness, gloss, and color change of dental enamel after being brushed with toothpastes containing diamond powder and traditional abrasives. MATERIALS AND METHODS: Seventy enamel slabs were derived from 70 bovine incisors. The slabs were brushed with six different toothpastes and artificial saliva as a negative control. The specimens were then stained with black tea mixed with citric acid (3 days, pH = 4) and again brushed with the same toothpastes. Ra (contact profilometer), gloss (glossmeter), and color (CIE L* a* b* system) values were measured after each step. RESULTS: Emoform-F Diamond (contains diamond powder and traditional abrasives) offered significantly the best improvement of Ra and gloss values after the first brushing sequence and the best recovery of the brightness of enamel after staining and second brushing sequence (P < .05). AMC 2.5 (contains only diamond powder as abrasive) was not able to offer such improvement. CONCLUSION: Diamond powder as an additional abrasive in toothpastes could be able to offer a further improvement of Ra , gloss, and color values of enamel.

Accuracy of remote diagnoses using intraoral scans captured in approximate true color: a pilot and validation study in teledentistry.

BACKGROUND: Intraoral scans (IOS) provide three-dimensional images with approximate true colors representing a possible tool in teledentistry for remote examination. The aim of the present cross-sectional validation study was, therefore, to evaluate the levels of agreement between remote diagnoses derived from IOS and diagnoses based on clinical examinations for assessing dental and periodontal conditions. METHODS: The test sample comprised 10 patients representing different clinical conditions. Following the acquisition of IOS (Trios, 3Shape), a full-mouth dental and periodontal examination was done and periapical radiographs were taken. Ten dentists were asked to perform dental and periodontal scorings for each of the ten patients on a tablet computer presenting the IOS. Scores included diagnosis of gingivitis/periodontitis, and evaluated presence as well as amount of plaque and calculus, and presence of teeth exhibiting gingival recession, furcation involvement, erosion, tooth wear, stain, and non-carious cervical lesion, as well as presence of decayed, filled, and crowned teeth and implants. In a second round of assessments, the periapical radiographs were provided and the dentists were able to change the scores. The time for the remote assessment was recorded. The agreement between remote and clinical scorings (reference) was then analyzed descriptively. RESULTS: The mean time for the tele assessment was 3.17 min and the additional consultation of the radiographs accounted for another 1.48 min. The sensitivity and specificity values were 0.61 and 0.39 for gingivitis and 0.67 and 0.33 for periodontitis, with no relevant changes when radiographs were provided for the diagnosis of periodontitis (0.72 and 0.28). The agreement for dichotomized dental and periodontal indices ranged between 78 and 95%. With the provision of radiographs, the remote examiners were able to detect existing filled teeth, crowned teeth, and implants, whereas the detection of decayed teeth (70%) was not improved. CONCLUSIONS: The remote examination using IOS was effective in detecting dental findings, whereas periodontal conditions could not be assessed with the same accuracy. Still, remote assessment of IOS would allow a time-efficient screening and triage of patients. Improvement of the image quality of IOS may further allow to increase the accuracy of remote assessments in dentistry. According to the Swiss Regulation this investigation is not a clinical trial and therefore no registration in a WHO-registry is needed.

The amount of keratinized mucosa may not influence peri-implant health in compliant patients: A retrospective 5-year analysis.

AIM: (a) To investigate the influence of the keratinized mucosa (KM) on peri-implant health or disease and (b) to identify a threshold value for the width of KM for peri-implant health. MATERIALS AND METHODS: The total dataset was subsampled, that is one implant was randomly chosen per patient. In 87 patients, data were extracted at baseline (prosthesis insertion) and 5 years including the width of mid-buccal KM, bleeding on probing, probing depth, plaque index and marginal bone level (MB). Spearman correlations with Holm adjustment for multiple testing were used for potential associations. RESULTS: Depending on the definition of peri-implant diseases, the prevalence of peri-implantitis ranged from 9.2% (bleeding on probing threshold: <50% or ≥50%) to 24.1% (threshold: absence or the presence). The prevalence of peri-implant mucositis was similar, irrespective of the definition (54%-55.2%). The width of KM and parameters for peri-implant diseases demonstrated negligible (Spearman correlation coefficients: -0.2 < ρ < 0.2). No threshold value was detected for the width of mid-buccal KM in relation to peri-implant health. CONCLUSION: The width of KM around dental implants correlated to a negligible extent with parameters for peri-implant diseases. No threshold value for the width of KM to maintain peri-implant health could be identified.

Comparison of Profilometric and Microindentation Analyses for Determining the Impact of Saliva on the Abrasion of Initially Eroded Enamel.

The aim of this in vitro study was to investigate the impact of saliva on the abrasion of eroded enamel using two measuring methods. A total of 80 bovine enamel specimens from 20 bovine incisors were allocated to four experimental groups (n = 20 specimens per group). After baseline surface microhardness (SMH) measurements and profilometry all specimens were subjected to erosion (2 min, 1% citric acid, pH: 3.6, 37°C). SMH was determined again, and the depths of the Knoop indentations were calculated. Thereafter, specimens were incubated in human saliva (group 1 - no incubation/control, group 2 - 0.5 h, group 3 - 1 h, group 4 - 2 h) before toothbrush abrasion was performed. After final SMH measurements and profilometry, indentations were remeasured, and surface loss was calculated. SMH did not return to baseline values regardless of the length of saliva incubation. Further, an irreversible substance loss was observed for all specimens. With the indentation method, significantly (p < 0.05) more substance loss was found for controls (least square means ± standard error of 198 ± 19 nm) than for groups 2-4 (110 ± 10, 114 ± 11, and 105 ± 14 nm). Profilometric assessment showed significantly more substance loss for controls (122 ± 8 nm) than for group 4 (106 ± 5 nm). Intraclass correlation for interrater reliability between measurement methods was low (0.21, CI: 0.1-0.3), indicating poor agreement. Exposure of eroded enamel to saliva for up to 2 h could not re-establish the original SMH. The amount of measured substance loss depended on the measurement method applied.

Efficacy of chlorhexidine rinses after periodontal or implant surgery: a systematic review.

BACKGROUND: Biofilm management and infection control are essential after periodontal and implant surgery. In this context, chlorhexidine (CHX) mouth-rinses are frequently recommended post-surgically. Despite its common use and many studies in this field, a systematic evaluation of the benefits after periodontal or implant surgery is-surprisingly-still missing. OBJECTIVES: To evaluate the benefits of chlorhexidine rinsing after periodontal or implant surgery in terms of plaque and inflammation reduction potential. Furthermore, to screen whether the concentration changes or additives in CHX solutions reduce side effects associated with its use. MATERIALS AND METHODS: A systematic literature search was performed for clinical trials, which compared CHX rinsing after periodontal or implant surgery with rinsing using placebo, non-staining formulations, or solutions with reduced concentrations of the active compound. Four databases (Medline, PubMed, Embase, Cochrane) were searched up to June 2018. Two reviewers independently identified and screened the literature. RESULTS: From 691 titles identified, only eleven publications met the inclusion criteria and were finally included. Mainly early publications assessed the benefits of CHX over placebo rinsing, whereas more recent publications focused more on the evaluation of new formulations with regard to effectiveness and side effects. The use of CHX after surgery showed in general significant reduction in plaque (means of 29-86% after 1 week) and bleeding (up to 73%) as compared to placebo. No consensus, however, was found regarding the most beneficial CHX formulation avoiding side effects. CONCLUSION: Chlorhexidine rinsing helps to reduce biofilm formation and gingival inflammation after surgery. However, no additional reduction of periodontal probing depth over any given placebo or control solution could be found irrespective of whether CHX was used or not. The use of additives such as antidiscoloration systems (ADS) or herbal extracts may reduce side effects while retaining efficacy. CLINICAL RELEVANCE: Within the limitations of this review, it can be concluded that CHX may represent a valuable chemo-preventive tool immediately after surgery, during the time period in which oral hygiene capacity is compromised. To reduce the side effects of CHX and maintain comparable clinical effects, rinsing with less concentrated formulations (e.g., 0.12%) showed the most promising results so far.