Gingival Displacement in the Vertical and Horizontal Dimension under the Condition of Mild Gingivitis—A Randomized Clinical Study

This randomized clinical study aimed at quantifying the gingival displacement performance in the vertical and horizontal directions of the 3M™ Astringent Retraction Paste (3M Oral Care, Seefeld, Germany) in comparison with the double-cord technique with aluminum chloride as an astringent. Afterward, any soft-tissue changes were assessed for 12 months. After inducing mild gingivitis, 18 probands received the intervention ‘cord’ and 22 probands received the intervention ‘paste’ at the palatal half of upper premolars prior to conventional impression making. The resulting plaster casts were digitized and analyzed for the vertical and horizontal gingival displacement, applying a newly developed computer-assisted methodology. The entire palatal half of the tooth was evaluated instead of only single sites. Under the condition of mild gingivitis, the gingival displacement performance was comparable for both techniques in the horizontal direction (width) and only somewhat better for the cord technique in the vertical direction (depth). The magnitude of displacement was in a similar range in both directions, with somewhat higher values in the vertical direction. The marginal gingiva height changes were of such low extent during the follow-up period of 12 months with only minimally higher values for the paste that they cannot be considered as clinically relevant recessions.

Comparative efficacy of different flapless ridge preservation techniques: A systematic review and meta-analysis

Although the efficacy of ridge preservation is well-documented, there is a lack of robust evidence regarding the influence of different surgical techniques. Flapless approaches are thought to be better at preserving soft tissue architecture and have been suggested for mild to moderate defects. This review investigates the efficacy of different flapless techniques for ridge preservation in mild to moderate defects with <50% buccal bone loss. PubMed, EMBASE, and Cochrane Library databases were searched to obtain relevant articles published in English from 1974 to December 2019. The primary outcome was horizontal and vertical hard tissue dimensional changes. Soft tissue changes were evaluated as a secondary outcome. The Bio-Col technique, subperiosteal tunnel technique, and hard tissue with autogenous soft tissue graft/collagen matrix technique were identified. Eight studies were included, and quantitative analyses were performed for four studies for the primary outcome variables. The meta-analysis revealed significant reductions for horizontal changes (WMD = 2.56 mm, 95% CI [2.18, 2.95]), vertical mid-buccal (WMD = 1.47 mm, 95% CI [1.04, 1.90]), and vertical mid-lingual (WMD = 1.28 mm, 95% CI [0.68, 1.87]), in favor of flapless ridge preservation techniques. Subgroup analysis based on technique suggest minimal hard tissue differences. The efficacy of flapless ridge preservation techniques on soft tissue changes was inconclusive. In conclusion, flapless ridge preservation techniques are effective for mild to moderate defects. The technique or material used to close the extraction socket does not seem to significantly affect hard tissue changes, while the effect on soft tissue changes warrants further investigation.

Medical Image Three-Dimensional Simulation Technology in Hospital Clinical Practice

We performed three-dimensional reconstruction of facial CT scan images of patients with mandibular angle hypertrophy to explore the related factors of mandibular angle hypertrophy. At the same time, the article uses the results of three-dimensional reconstruction to simulate the clinical operation and obtain the final operation method. It was found that all patients were able to obtain the proper surgical plan from the three-dimensional reconstructed images and can get the hypertrophy factor of the mandibular angle. For this reason, we conclude that computer reconstruction simulation technology can obtain the tissue changes before and after osteotomy of mandibular angle hypertrophy and get the cause of hypertrophy. Three-dimensional reconstruction simulation technology is the best auxiliary diagnosis plan for the selection of mandibular angle surgery.

Comparison of AdvanSync2® and Twin Block Appliances in Treatment of Class II Malocclusion With Retrognathic Mandible—An Observational Retrospective Study

Objectives: To evaluate the treatment outcomes between Twin Block and AdvanSync2® appliances by comparing the skeletal, dentoalveolar, and soft tissue changes. Materials and Methods: Radiographic data of 20 patients were retrospectively analyzed. Data were selected from patients in their skeletal growth spurt as evaluated by the cervical vertebral maturation method (CVMI 2, 3, and 4), with class II malocclusion characterized with retrognathic mandible (ANB > 4°, SNB < 77°, FMA = 25 ± 5°, overjet > 5 mm). There were 10 patients in each group that underwent orthodontic correction for class II malocclusion: either using Twin Block or AdvanSync2®. Independent t test and Paired t test and chi-square tests were used for the data analysis. The level of statistical significance was set at P value ≤.05. Results: The chronological and skeletal age were similar in both the groups. Records were taken for the functional treatment with mean treatment span of 8 ± 1 month. Changes in SNB (group I = 1.59°, group II = 3.11°) ( P < .01), Co-Gn (group I = 2.89 mm, group II = 5.34 mm), and U1-L1° (group I = −1.51°, group II = 2.97°) showed statistically different outcome between the groups, when the pre-post data were studied. Rest of the variables—cranial base, maxillary skeletal, mandibular skeletal, intermaxillary, vertical skeletal, maxillary dentoalveolar, mandibular dentoalveolar, and soft tissue—showed similar outcome ( P > .05). Conclusion: Both appliances lead to desirable outcomes in the correction of class II malocclusion. AdvanSync2® resulted in inducing more of changes in SNB and effective mandibular length as compared to Twin Block. Overjet and molar relation improved significantly with both the appliances. Both the appliances resulted in similar skeletal, dentoalveolar, and soft tissue changes.

Characteristics and morphology of lipohypertrophic lesions in adults with type 1 diabetes with ultrasound screening: an exploratory observational study

IntroductionLipohypertrophy is a common complication of exposure to insulin therapy. Despite the prevalence of lipohypertrophy and its potentially hazardous effects on glucose regulation, it remains a relatively understudied problem in diabetes. The objective of this study was to characterize lipohypertrophic tissue using ultrasound in adults with type 1 diabetes.Research design and methodsAn observational study of 74 people with type 1 diabetes from a diabetes center in South East London. Participants’ insulin exposed areas were scanned with ultrasound, with a high-frequency linear probe (6–13 MHz). The observed tissue changes were described, measured and graded according to nodule size and thickness of the dermal layer.ResultsParticipants mean age and diabetes duration were 40.6 (±14.2) and 18.3 (±10.9) years, respectively, and 60% (n=44) were male. A total of 740 lipohypertrophic nodules were observed, ranging from 1.8 mm to 40 mm in width. The mean (SD/range) number of nodules per participants was 10.4 (±6.2/1–29). Delineation between the dermal layers was disrupted in all current injection sites. In 52 participants (70%), there was a 30% increase in dermal thickness compared with local none injected tissue, and in 36 participants (48%) the increase was 50%. The level of thickness was >3 mm in the abdominal areas of 22 (40%) of these participants and in thighs of eight participants (17.8%). Hypoechogenic areas suggestive of necrotic tissue were observed within the lipohypertrophic nodules of 22 (30%) participants. Needle length and nodule depth were correlated (r=0.69, p<0.001). A conceptual model of the insulin exposed tissue changes observed was constructed.ConclusionsThe study confirms that insulin-exposed tissue changes are heterogenous and has provided conceptual and grading frameworks for classifying these changes. Further studies are required to establish the clinical implications of these classifications, in relation to glucose regulation and other clinical parameters.

Comparison of dentoskeletal and soft tissue changes between tooth-borne and tooth-bone-borne hybrid nonsurgical rapid maxillary expansions in adults: a retrospective observational study

Background Despite the gradual increase in the use of rapid maxillary expansion (RME), specifically RME with the aid of skeletal anchorage in adults, there have been no reports comparing dentoskeletal and soft tissue changes between nonsurgical tooth-borne and tooth-bone-borne RMEs in adults. This study aimed to analyse differences in dentoskeletal and soft tissue changes between tooth-borne and tooth-bone-borne RMEs using a similar appliance design and the same expansion protocol in adult patients. Methods Twenty-one patients with tooth-borne expansion (a conventional expansion screw with two premolars and two molar bands for dental anchorage [T-RME]) and the same number of patients with tooth-bone-borne hybrid expansion (a conventional expansion screw with two premolar and two molar bands for dental anchorage and four mini-implants in the palate for skeletal anchorage [H-RME]) were included. Dentoskeletal and soft tissue variables at pretreatment (T1) and after expansion (T2) were measured using posteroanterior and lateral cephalograms and frontal photographs. The sex distribution of the two groups was analysed using the chi-square test, and the change after RME in each group was evaluated using the Wilcoxon signed-rank test. Differences in pretreatment age, expansion duration, post-expansion duration, and dentoskeletal and soft tissue changes after RME between the two groups were determined using the Mann–Whitney U test. Results There were no significant differences in the expansion protocol, pretreatment conditions, and sex distribution between the two groups. Despite similar degrees of dental expansion at the crown level between the two groups, H-RME induced increased skeletal and parallel expansion of the maxilla compared to T-RME. After expansion, H-RME demonstrated increased forward displacement of the maxilla without significant changes in the vertical dimension, while T-RME exhibited increased backward displacement of the mandible, increased vertical dimension, and decreased overbite. Both groups showed significant retroclination and extrusion of the maxillary incisors without significant intergroup differences. There were no significant soft tissue changes between the two groups. Conclusion This study suggests that using skeletal anchorage in RME may induce increased skeletal and parallel expansion of the maxilla without significant effects on the vertical dimension.

Microstructural Tissue Changes in a Rat Model of Mild Traumatic Brain Injury

Our study investigates the potential of diffusion MRI (dMRI), including diffusion tensor imaging (DTI), fixel-based analysis (FBA) and neurite orientation dispersion and density imaging (NODDI), to detect microstructural tissue abnormalities in rats after mild traumatic brain injury (mTBI). The brains of sham-operated and mTBI rats 35 days after lateral fluid percussion injury were imaged ex vivo in a 11.7-T scanner. Voxel-based analyses of DTI-, fixel- and NODDI-based metrics detected extensive tissue changes in directly affected brain areas close to the primary injury, and more importantly, also in distal areas connected to primary injury and indirectly affected by the secondary injury mechanisms. Histology revealed ongoing axonal abnormalities and inflammation, 35 days after the injury, in the brain areas highlighted in the group analyses. Fractional anisotropy (FA), fiber density (FD) and fiber density and fiber bundle cross-section (FDC) showed similar pattern of significant areas throughout the brain; however, FA showed more significant voxels in gray matter areas, while FD and FDC in white matter areas, and orientation dispersion index (ODI) in areas most damage based on histology. Region-of-interest (ROI)-based analyses on dMRI maps and histology in selected brain regions revealed that the changes in MRI parameters could be attributed to both alterations in myelinated fiber bundles and increased cellularity. This study demonstrates that the combination of dMRI methods can provide a more complete insight into the microstructural alterations in white and gray matter after mTBI, which may aid diagnosis and prognosis following a mild brain injury.