Ultrasound insonation angle and scanning imaging modes for imaging dental implant structures: A benchtop study.

INTRODUCTION: High frequency ultrasound has shown as a promising imaging modality to evaluate peri-implant tissues. It is not known if the ultrasound imaging settings might influence ultrasound's ability to differentiate implant structures. The aim of this benchtop study was to evaluate the dependence of ultrasound on imaging angles and modes to measure implant geometry-related parameters. METHODS: A clinical ultrasound scanner (ZS3, Mindray) with an intraoral probe (L30-8) offering combinations of harmonic and compound imaging modes was employed for imaging 16 abutments and 4 implants. The samples were mounted to a micro-positioning system in a water tank, which allowed a range of -30 to 30-degree imaging angles in 5-degree increment between the probe and samples. The abutment angle, implant thread pitch and depth were measured on ultrasound, compared to the reference readings. The errors were computed as a function of the image angles and modes. All samples were replicated 3 times for 3 image modes and 11 image angles, thus resulting in 2,340 images. RESULTS: The mean errors of ultrasound to estimate 16 abutment angles, compared to the reference values, were between -1.8 to 2.7 degrees. The root mean squared error (RMSE) ranged from 1.5 to 4.6 degrees. Ultrasound significantly overestimated the thread pitch by 26.1 µm to 36.2 µm. The error in thread depth measurements were in a range of -50.5 µm to 39.6 µm, respectively. The RMSE of thread pitch and depth of the tested 4 implants was in a range of 34.7 to 56.9 µm and 51.0 to 101.8 µm, respectively. In most samples, these errors were independent of the image angle and modes. CONCLUSIONS: Within the limitations of this study, high-frequency ultrasound was feasible in imaging abutments and implant fixtures independent of scanning angle within ±30° of normal incidence and for compounding and non-compounding-based imaging modes.

Immediate Implant With Provisionalization and Soft Tissue Grafting After 4-Year Follow-Up.

INTRODUCTION: This paper presents a case report of immediate implant placement (IIP) with a provisionalization technique to restore function and esthetics with follow-up after 4 years. CASE PRESENTATION: Minimally traumatic extraction was performed with IIP, soft-tissue grafting, and immediate provisional crown. Six months after optimal healing, the patient was submitted to an esthetic restorative work through veneers in lithium disilicate. Fourteen-month and 4-year follow-up visits revealed stability of the peri-implant soft-tissues with peri-implant health status, with the evaluation of the pink and white esthetic score, yielding to mean scores, respectively, in 14 months of 11.62 ± 2.07 (pink esthetic score [PES]) and 18.25 ± 1.46 (PES/white esthetic score [WES]) and in 4 years of 11.0 ± 1.32 (PES) and 17.62 ± 0.65 (PES/WES). Intraoral digital radiographs showed minimal crestal bone level changes throughout the follow-up period. Thus, IIP is a sensitive technique procedure, and a 3D implant position is crucial for success. CONCLUSION: Immediate implant with grafting to fill the gap and soft tissue augmentation led to less horizontal changes and stable mucosal margin, and immediate provisionalization helped to maintain soft tissue architecture, and proper case selection is key for clinical success.

Autologous Platelet Concentrate of 2nd and 3rd generations efficacy in the surgical treatment of gingival recession: an overview of systematic reviews.

BACKGROUND: Autologous platelet concentrate (APC)/platelet-rich fibrin (PRF) of second and third generations has increased use in periodontics to optimize wound healing. Few systematic reviews (SRs) have reported improved clinical outcomes, while other studies reported significantly better results for the connective tissue graft (CTG). There is still unclear clinical evidence about APC/PRF use to treat gingival recession (GR) defects. Then, the purpose of this SR was to evaluate the use of APC/PRF membranes (2nd and 3rd generations) in root coverage (RC) procedures and assess its efficacy as a substitute biomaterial. MATERIALS AND METHODS: An electronic search was conducted in PubMed, Cochrane Central, Web of Science, Google Scholar, BookSC databases, and gray literature. The search strategy, without date restriction up to April 2020, included keywords as "platelet-rich fibrin," "autologous platelet concentrates," "blood," "systematic review," "periodontics," "surgery," "tissue," "gingiva," "gingival recession," "connective tissue," "graft," and "root coverage." The methodological quality was evaluated through the AMSTAR2, and a population, index test, comparator, outcome strategy was used to assess specific clinical parameters such as recession depth, clinical attachment levels, and RC outcomes. RESULTS: Nine SRs were included. Only three articles described the technique of APC/PRF production. Three studies reported unfavorable outcomes using APC, while six reported favorable results and postoperative discomfort reduction. Articles included in this SRs that provided information about APC/PRF membranes (n = 13) showed no significant difference between APC/PRF and the control group for the parameters analyzed. CONCLUSIONS: This implies that APC/PRF may be considered a feasible substitute biomaterial for treating GR defects, although the CTG still provides superior outcomes. Further long-term and controlled studies are needed to verify this finding.

Effect of different implant placement depths on crestal bone levels and soft tissue behavior: A 5-year randomized clinical trial.

OBJECTIVES: This randomized clinical trial analyzed the long-term (5-year) crestal bone changes and soft tissue dimensions surrounding implants with an internal tapered connection placed in the anterior mandibular region at different depths (equi- and subcrestal). MATERIALS AND METHODS: Eleven edentulous patients were randomly divided in a split-mouth design: 28 equicrestal implants (G1) and 27 subcrestal (1-3 mm) implants (G2). Five implants were placed per patient. All implants were immediately loaded. Standardized intraoral radiographs were used to evaluate crestal bone (CB) changes. Patients were assessed immediately, 4, 8, and 60 months after implant placement. The correlation between vertical mucosal thickness (VMT) and soft tissue recession was analyzed. Sub-group analysis was also performed to evaluate the correlation between VMT and CB loss. Rank-based ANOVA was used for comparison between groups (α = .05). RESULTS: Fifty-five implants (G1 = 28 and G2 = 27) were assessed. Implant and prosthetic survival rate were 100%. Subcrestal positioning resulted in less CB loss (-0.80 mm) when compared to equicrestal position (-0.99 mm), although the difference was not statistically significant (p > .05). Significant CB loss was found within the G1 and G2 groups at two different measurement times (T4 and T60) (p < .05). Implant placement depths and VMT had no effect on soft tissue recession (p > .05). CONCLUSIONS: There was no statistically significant difference in CB changes between subcrestal and equicrestal implant positioning; however, subcrestal position resulted in higher bone levels. Neither mucosal recession nor vertical mucosa thickness was influenced by different implant placement depths.

Using Digital Technique to Obtain the Ideal Soft Tissue Contour in Immediate Implants With Provisionalization.

This paper presents a newly developed digital technique to make a provisional crown that mimics the natural tooth during immediate implant placement. Basically, a digital technique results in a precise transfer tooth emergence profile for provisional restoration in immediate implant placement so that an ideal periimplant soft tissue contour can be maintained. The architecture of extraction socket is obtained digitally before the surgery that allows for implant planning by position of the implant as well as the emergence profile of provisional restoration. The introduction of this approach provides a versatile, precise, and predictable procedure leading to better esthetic outcomes.

Factors Influencing the Presence of Papilla between Adjacent Implants and between a Tooth and an Implant.

AIM: The aim this study was to evaluate the factors that influence the presence or absence of the interproximal papilla between implants adjacent to the teeth or other implants, through clinical and radiographic evaluation. MATERIAL AND METHODS: The non-probabilistic sample comprised 44 patients of both genders aged between 21 and 68 years, rehabilitated with 114 osseointegrated implants. Through a retrospective clinical study, the patients were divided according to the presence or absence of the interproximal papilla: Group 1 - Absence of Papilla, Group 2 - Partial Presence of Papilla and Group 3 - Total Presence of Papilla. The success of the implants, the periodontal biotype, and the vertical and horizontal distances of the interproximal regions included in the study were evaluated. RESULTS: Of the 114 implants, 46.5% were considered unsuccessful, and bleeding was present in 29.8%. The periodontal biotype presented as thin and scalloped was found in 85.1% of the regions. The evaluation of the groups according to the confirmation of the interproximal space showed a statistically significant difference (p = 0.007), with 61.9% of the wide and long interproximal spaces classified as Group 1, while 31% of the narrow and short interproximal spaces were classified as Group 3. CONCLUSION: It was concluded that the morphology of the interproximal space was the factor that was most strongly associated with the presence or absence of the interproximal papilla.

Resonance Frequency Analysis of Dental Implants With 2 Types of Surface Treatment Submitted to Immediate Loading: A Prospective Clinical Study.

BACKGROUND: Characteristics of the implant surface may benefit osseointegration, and the knowledge of this process in diverse clinical situations may play a role in implant dentistry practice. PURPOSE: The aim of the present study was to compare the stability of dental implants with different types of surface treatment. MATERIALS AND METHODS: Fifty-five implants were placed in the mandibles of 11 fully edentulous patients. Group 1 (G1) consisted of 27 implants with a hydrophilic surface. Group 2 (G2) consisted of 28 implants (double sandblasting and acid etching). Implants were distributed randomly; equal surfaces were not placed contiguously. Measurements were taken after surgery (baseline) and 10, 30, 60, and 90 days, 4 and 8 months after surgery. Resonance frequency analysis (RFA) was used for determining the stability. RESULTS: No statistically significant differences were found. The largest difference in implant stability quotient (ISQ) between groups occurred at the first evaluation (ISQ ≈ 69.8 in G1 and ≈ 68.4 in G2). Reductions in stability were more accentuated in the first month, returning to values similar to baseline in the subsequent months, with peak stability reached at 8 months (ISQ ≈ 69.8 in G1 and ≈ 69.8 in G2). CONCLUSION: No statistically significant differences were found in the stability of the implants placed in edentulous mandibular arch, submitted to immediate loading analyzed using RFA.

Effect of different implant placement depths on crestal bone levels and soft tissue behavior: a randomized clinical trial.

OBJECTIVES: This randomized clinical trial analyzed crestal bone changes and soft tissue dimensions surrounding implants with an internal tapered connection placed in the mandible anterior region at different depths (equicrestal and subcrestal). MATERIALS AND METHODS: Eleven edentulous patients (five implants per patient) were randomly divided in a split-mouth design: G1, 28 equicrestal implants; and G2, 27 subcrestal implants. All implants were immediately loaded. Correlation between keratinized tissue width (KTW) and vertical mucosa thickness (MT) with soft tissue recession was analyzed. Intraoral radiographs were used to evaluate crestal bone changes. Patients were assessed immediately, 4-, and 8-months after implant placement. Rank-based ANOVA-type statistical test was used for comparison between groups (α = 0.05). RESULTS: Fifty-five implants (G1 = 28 and G2 = 27) were assessed in 11 patients. Implant survival rate was 100% for both groups. Both tested implant placement depths presented similar crestal bone loss (P > 0.05). Significant crestal bone loss for each group was found in the different measurement times (T4 and T8) (P < 0.05). Implant placement depths, KTW, and vertical MT had no effect on soft tissue recession (P > 0.05). CONCLUSIONS: Different implant placement depths do not influence crestal bone changes. Soft tissue behavior is not influenced by different implant placement depths or by the amount of keratinized tissue.

Análise do desvio angular pelo escaneamento a laser de modelos, antes e após cirurgia guiada flapless na arcada maxilar edêntula: estudo in vitro com um sistema comercialmente disponível / Analysis of angular deviation by laser scanning of plaster models before and after flapless guided surgery in edentulous maxillary arches: in vitro study with a commercially available system

Objetivo: este estudo foi idealizado com a finalidade de comparar as posições dos análogos em modelos de gesso, obtidos antes e após o procedimento cirúrgico de instalação dos implantes, em dez casos clínicos. Material e métodos: foram selecionados dez guias prototipados de maxilas edêntulas, que já haviam sido utilizados para a instalação guiada de implantes e que já estavam com as próteses instaladas. Cilindros posicionadores de análogos de minipilar foram adaptados para obtenção dos modelos de gesso pré-cirúrgicos (modelo 1). Também foram reunidos os modelos dos casos que haviam sido obtidos através da moldagem realizada em boca após a instalação dos intermediários (modelo 2). Todos foram submetidos a escaneamento a laser, e a comparação entre os modelos foi realizada virtualmente com um software específico. Os dados foram analisados estatisticamente utilizando o teste de Wilcoxon (p < 0,05). Resultados: foi encontrada uma média de desvio angular de 3,17o ± 1,78o (p=0,000). A média do desvio angular encontrada na comparação entre os dois modelos avaliados foi semelhante a desvios encontrados na literatura. Conclusão: técnicas como a da adaptação passiva devem ser utilizadas com o objetivo de compensar tais desvios e facilitar o procedimento técnico laboratorial, entregando a prótese final em menos tempo.

Objective: this study compared the positions of the analogs in plaster models obtained before and after implant placement in 10 clinical cases. Material and methods: ten CAD/CAM surgical guides for maxillary edentulous patients were selected and which had already been used for the guided implant placement and with the final prosthesis already fabricated. To generate the pre-surgical cast model (model 1), mini conical replicas were mounted on the guiding sleeves using cylinder positioners. The models obtained through an impression after the surgical procedures were also analyzed (model 2). Each plaster model was subjected to laser scanning and the comparison between models was performed in specialized software. The statistical analyses were performed using Wilcoxon test (p < 0.05). Results: a mean angular deviation of 3.17o ± 1.8o (p=0.000) was found. The average angular deviation found in the comparison between the two models evaluated was similar to deviations in the literature. Conclusion: techniques such as passive adaptation, must be used in order to compensate the deviations and improve laboratory procedures, speeding the final denture delivery in less time.

Taxa de falha em implantes dentários de estágio único com conexão cone-morse em função do tempo de carregamento: avaliação retrospectiva de 245 implantes / The failure rate of one-stage, morse cone dental implants according to loading time periods: a retrospective evaluation of 245 implants

Objetivo: determinar a ocorrência de insucessos conforme o tempo de carregamento em implantes dentários de estágio único. Material e métodos: neste estudo retrospectivo com série de casos, após aplicação dos critérios de inclusão e exclusão, um banco de dados foi utilizado para coleta de desfechos clínicos (queixas subjetivas, infecção com supuração, mobilidade, profundidade de sondagem, sangramento gengival, e recessão gengival) e radiográficos (perda óssea anual). O tempo de carga foi dividido em G1(< 1 ano de carga), G2 (≥ 1 e < 5 anos de carga) e G3 (≥ 5 anos de carga). Análises bivariadas, de máxima verossimilhança, de regressão logística binária e OR foram aplicadas (nível de significância 5%). Resultados: 245 implantes cone-morse tissue level e bone level (G1=48, G2=103, G3=94; insucesso geral = 36,73%) foram avaliados em 111 indivíduos. O insucesso dos implantes foi maior em G1 (qui-quadrado = p < 0,001) do que no G2 e G3. A chance de perda de implantes no G1 (OR = 9,8) foi maior (p < 0,001) comparada ao G2 e G3 (sem diferenças estatísticas). Em geral, a radiolucência, o sangramento à sondagem, profundidade > 5 mm, e a perda óssea anual peri-implantar mostraram signifi cância estatística (qui-quadrado, p ≤ 0,001). Entretanto, apenas o sangramento (p < 0,001) e a perda óssea (p=0,014) mostraram significância na comparação entre grupos. Conclusão: a taxa de insucessos em implantes de estágio único conexão cone-morse foi maior no primeiro ano de carregamento.

Objective: to determine the failure rates of one-stage morse cone dental implants according to loading time periods. Material and Methods: in this retrospective case series study, after inclusion and exclusion criteria, a database was screened to collect clinical (subjective complaints, infection with suppuration, mobility, probing depth, gingival bleeding, and gingival recession) and radiographic (annual bone loss) outcomes. The loading time was divided into G1 (<1 year), G2 (≥ 1 and <5 years) and G3 (≥ 5 years). Bivariate analysis, maximum likelihood, and the binary logistic regression with OR were applied (5% significance level). Results: 245 morse cone implants (tissue and bone level types; G1 = 48, G2 = 103, G3 = 94, overall failure = 36.73%) were evaluated in 111 subjects. The implant failure was higher in G1 (chi-square = p < 0.001) than in G2 and G3. The chance of implant loss in G1 (OR = 9.8) was higher (p < 0.001) compared to G2 and G3 (no statistical differences). In general, radiolucency, bleeding on probing, probing depth > 5 mm, and the peri-implant annual bone loss demonstrated statistical signifi cance (chi-square, p ≤ 0,001). However, only bleeding on probing (p < 0.001) and bone loss (p = 0.014) were significant on comparison among groups. Conclusion: the failure rate of one-stage morse cone dental implants was higher in the fi rst year of loading.

Comparação de critérios de diagnóstico clínico de periodontite em diabéticos / Comparison of clinical diagnostic criteria of periodontitis in diabetics

Objetivo: A diversidade de critérios de diagnóstico clínico para periodontite em trabalhos científicos tem dificultado a determinação adequada da frequência desta doença e diminuído a possibilidade de comparações entre os estudos. O objetivo foi comparar cinco critérios encontrados na literatura que a associam a profundidade de sondagem (PS) e a perda de inserção clínica (PIC) na determinação da doença periodontal. Material e Métodos: 92 pacientes diabéticos foram submetidos à avaliação periodontal, sendo registrado medidas de PS e PIC em seis sítios em cada dente, e sangramento a sondagem. Com os dados registrados foi calculada a frequência da doença periodontal aplicando os diferentes critérios e posteriormente foi avaliado a concordância entre 5 critérios, utilizando o índice de Kappa (K). Resultados: A frequência de casos de periodontite para os critérios I (PIC ≥ 5 mm em 4 ou mais sítios, e pelo menos um deles com PS ≥ 4 mm), II (PS ≥ 4 mm e PIC ≥ 4 mm em pelo menos um sítio), III (4 ou mais dentes com pelo menos 1 sítio com PS ≥ 4 mm e PIC ≥ 3 mm), IV (2 ou mais dentes com pelo menos 1 sítio PS ≥ 4 mm e PIC ≥ 3mm) e V (PIC ≥ 6 mm em 2 ou mais dentes e PS ≥ 5 mm em 1 ou mais sítios) foi de 59,8%, 67,4%, 51,1%, 56,5% e 57,6%, respectivamente. A concordância entre os critérios de diagnósticos clínicos pelo Kappa variou entre 0,47 (47%) e 0,89 (89%). Conclusão: A frequência de distribuição da periodontite em pacientes diabéticos utilizando diversos critérios de diagnóstico não apresentou grande variação, e a concordância foi considerada entre razoável a boa e excelente. (AU)

Objective: The variability of clinical diagnostic criteria for periodontitis in scientific papers has difficulted the proper determination of the frequency of this disease and decreases the possibility of comparisons between studies. The aim of this study was to compare five criteria found in the literature associated with probing depth (PD) and clinical attachment loss (CAL) in the determination of periodontal disease. Methods: 92 diabetic patients underwent periodontal evaluation, and measures of PD and CAL was performed at six sites on each tooth, and bleeding on probing. With the recorded data the frequency of periodontal disease was calculated by applying different criteria and was subsequently evaluated the correlation between 5 criteria, using the Kappa index (K). Results: The frequency of cases of periodontitis for the criteria I (CAL ≥ 5 mm in 4 or more sites, with at least one site PD ≥ 4 mm), II (PD ≥ 4 mm and CAL ≥ 4 mm in at least one site), III (4 or more teeth with at least one site PD ≥ 4 mm and CAL ≥ 3 mm), IV (2 or more teeth with at least one site PD ≥ 4 mm e CAL ≥ 3mm) e V (CAL ≥ 6 mm in 2 or more teeth and PD ≥ 5 mm in one or more sites) was 59.8%, 67.4%, 51.1%, 56.5% and 57.6%, respectively. The agreement between the criteria for clinical diagnosis by Kappa ranged from 0.47 (47%) and 0.89 (89%). Conclusion: The frequency distribution of periodontitis in diabetic patients using various diagnostic criteria did not show great variation, and the agreement was considered reasonable to good and excelente (AU)