GMGabriela Guadalupe Zambrano Manzaba

Gabriela Guadalupe Zambrano Manzaba

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Gabriela Guadalupe Zambrano Manzaba has a total of 39 co-authors. Here are the top co-authors by number of shared publications:


Latest Publications

  • Open Access

    Effect of Kissing on Salivary pH Recovery After Consumption of Acidogenic Beverages: A Randomised Clinical Trial

    by Marcelo Armijos Briones, Mariuxi Aguila Gaibor, Andrea Bermúdez Velásquez, Gabriela Guadalupe Zambrano Manzaba, Cristina Ludeña Sangurima, Wladimir Alejandro Guzmán Jara, Nicole Armijos Bazurto

  • Open Access

    Long-Term Aesthetic Performance of Freehand Direct Anterior Composite Resin Restorations: A Systematic Review and Meta-Analysis of Colour Alteration, Marginal Discolouration, and Surface-Quality Deterioration

    by Luis Chauca-Bajaña, Gabriela Guadalupe Zambrano Manzaba, Luis Fernando Campos Lascano, Nayely Jimena Teran Sanchez, Andrea Ordoñez Balladares, Marcela Alejandra Ordoñez Balladares, Byron Velasquez Ron, Míriam Teulé-Trull, José Martín-Cruces

    Background: Freehand direct composite resin veneers offer a minimally invasive approach for managing aesthetic alterations in anterior teeth; however, their long-term colour alteration and surface performance remain uncertain. This systematic review evaluated colour alteration, marginal discolouration, and surface-quality deterioration after at least 24 months of clinical service. Methods: MEDLINE/PubMed, Embase, Web of Science, Scopus, the Cochrane Library, and ClinicalTrials.gov were searched. Randomised and non-randomised trials and longitudinal clinical studies evaluating freehand direct anterior composite restorations were eligible. Risk of bias was assessed using RoB 2 and the JBI cohort checklist. Single-arm proportions were pooled separately using random-effects models with Freeman–Tukey transformation. Logit-REML models, binomial-normal generalised linear mixed models, Hartung–Knapp adjustments, leave-one-out analyses, and influence diagnostics were used as sensitivity analyses. Results: Eight studies were included. Colour alteration was evaluated in 893 restorations, with a pooled proportion of 14% (95% CI: 5–26%; I2 = 95.0%). Marginal discolouration involved 566 restorations and yielded a pooled proportion of 21% (95% CI: 10–34%; I2 = 91.8%). Surface-quality deterioration was assessed in 896 restorations, with a pooled proportion of 21% (95% CI: 9–35%; I2 = 95.6%). GLMM estimates were 11%, 19%, and 18%, respectively. Hartung–Knapp and leave-one-out analyses produced compatible results, although prediction intervals were wide. No study materially altered the overall interpretation. Conclusions: The pooled proportions of recorded aesthetic deterioration were 14% for colour alteration, 21% for marginal discolouration, and 21% for surface-quality deterioration. However, between-study heterogeneity was substantial, and prediction intervals were wide (0–63%, 0–68%, and 0–74%, respectively), indicating considerable variability in the outcomes expected across clinical settings. Absence of recorded deterioration should not be interpreted as equivalent to overall aesthetic success or clinical acceptability. Accordingly, the pooled estimates should be interpreted cautiously and primarily as average estimates across heterogeneous clinical settings.

  • Open Access

    Topical Hyaluronic Acid for Palatal Donor-Site Healing After Autogenous Gingival Graft Harvesting: A Systematic Review and Time-Specific Meta-Analysis with Clinical Implications for Postoperative Care

    by Luis Chauca-Bajaña, Hector Alfredo Lema Gutierrez, Gabriela Guadalupe Zambrano-Manzaba, Nayely Jimena Teran-Sanchez, Andrea Ordoñez-Balladares, Rosangela Caicedo-Quiroz, Roberto Tolozano-Benites, Marcela Alejandra Ordoñez Balladares, Carlos Carpio Cevallos, Byron Velasquez Ron

    Background: Palatal graft harvesting can cause pain, bleeding, and delayed healing, with postoperative recovery varying across patients and over time. Topical hyaluronic acid (HA) may reduce donor-site morbidity and promote tissue repair. Identifying the postoperative time points and clinical domains in which HA may provide benefit could support more informed, patient-centered postoperative management. Objective: To evaluate the time-specific effects of topical HA on palatal wound healing and postoperative morbidity after autogenous gingival graft harvesting and to examine their clinical implications for postoperative care. Methods: Randomized clinical trials comparing topical HA with placebo, no application, or standard care were reviewed. Separate random-effects meta-analyses were performed at each postoperative time point using risk ratios (RRs) for dichotomous outcomes and mean differences (MDs) for continuous outcomes. Between-study variance was estimated using REML. Leave-one-out, Hartung–Knapp, and formulation-based sensitivity analyses were performed. Risk of bias was assessed using RoB 2, and certainty of evidence using GRADE. Results: Eight randomized trials were included. HA increased complete epithelialization at day 14 (RR = 2.11; 95% CI, 1.13–3.94) and day 21 (RR = 1.62; 95% CI, 1.29–2.03). WHI favored HA at day 7 (MD = 0.58; 95% CI, 0.42–0.75). Pain reductions at days 3 and 7 and bleeding reductions at days 1 and 3 were not statistically significant. Analgesic consumption was lower at day 3 (MD = −0.80; 95% CI, −1.34 to −0.26), while color match favored HA at days 14 and 21. Hartung–Knapp analyses increased uncertainty for WHI, pain, and color match. No result was rated at high overall risk of bias; certainty ranged from low to very low. Conclusions: Topical HA appears to provide its most consistent benefit in accelerating palatal epithelialization and selected healing outcomes rather than uniformly reducing all dimensions of postoperative morbidity. These time- and outcome-specific effects may inform patient-centered and risk-adapted postoperative strategies, particularly when early wound closure is a clinical priority. However, the current aggregate evidence does not permit identification of individual treatment responders. Future adequately powered randomized trials incorporating standardized HA formulations, patient-level characteristics, potential effect modifiers, and harmonized outcome assessment are needed to support precision treatment selection.

  • Open Access

    Cell-Based Therapies for Periodontal Regeneration: A Systematic Review and Meta-Analysis with Future Implications for Personalized Medicine

    by Rafael X. Erazo Vaca, Gabriela G. Zambrano Manzaba, Luis-Chauca Bajaña, Andrea-Ordoñez Balladares, Andres-Villao Leon, Nayely J. Teran Sanchez, Gema N. Mendoza Manzaba, Rito A. Salazar Román, Jorge L. Teran Sanchez, David A. Flor Ronquillo, et al.

    Background/Objectives: Periodontitis is a chronic inflammatory disease characterized by progressive destruction of the periodontal supporting tissues. Regenerative responses may vary according to patient-related biological characteristics, periodontal defect morphology, the local inflammatory microenvironment, cellular source, biomaterial selection, and delivery strategy. Cell-based regenerative therapies may therefore provide a biological foundation for the future development of personalized periodontal regenerative approaches. This systematic review and meta-analysis evaluated the effectiveness of cell-based therapies for periodontal regeneration and considered how the current evidence may inform future personalized regenerative strategies. Methods: A comprehensive electronic search was conducted in MEDLINE via PubMed, Web of Science, Embase, and the Cochrane Library, with additional searches performed in SciELO and Latindex, in accordance with PRISMA guidelines. Randomized and quasi-randomized controlled clinical trials evaluating cell-based regenerative therapies for periodontal defects were included. The primary outcomes were clinical attachment level (CAL) gain and probing depth (PD) reduction, while radiographic bone regeneration was considered a secondary outcome. Standardized mean differences (SMDs) with 95% confidence intervals (CIs) were calculated using random-effects models. Leave-one-out sensitivity analyses were performed to assess the stability of the pooled estimates. Results: Six clinical trials were included in the qualitative synthesis, and five contributed to the quantitative analysis. Cell-based regenerative therapies showed a small, non-significant effect for CAL gain (SMD = 0.17; 95% CI: −0.12 to 0.45; I2 = 0%) and PD reduction (SMD = 0.13; 95% CI: −0.22 to 0.48; I2 = 33.0%). Radiographic bone regeneration showed a larger favorable effect, although statistical significance was not reached and substantial heterogeneity was present (SMD = 1.25; 95% CI: −0.08 to 2.58; I2 = 88.2%). Leave-one-out analyses did not materially alter the non-significant interpretation for CAL or PD, although some variation in effect magnitude and direction was observed. Radiographic bone regeneration was more sensitive to the exclusion of individual studies. Overall, superiority of cell-based regenerative therapies over control interventions was not demonstrated. Risk-of-bias assessment indicated a low overall risk for most randomized trials, with some concerns in one trial and moderate risk in the quasi-randomized study. Conclusions: Cell-based regenerative therapies showed preliminary but inconclusive signals of benefit for periodontal regeneration. However, no statistically significant superiority over control interventions was demonstrated for CAL gain, PD reduction, or radiographic bone regeneration. Further well-designed clinical trials are required before these approaches can be considered for routine or personalized periodontal regenerative strategies.

  • Open Access

    Association Between Periodontitis Severity and Oral Health-Related Quality of Life: A Cross-Sectional Study Using the 2017 Periodontitis Classification

    by Gabriela Zambrano Manzaba, Jazmin Rodríguez Grajales, Hector Alfredo Lema Gutierrez, Luis Chauca Bajaña, Mónica Gabriela Magaña Pérez, Gema Nallely Mendoza Manzaba, Rito Alfonso Salazar Roman, Daniela Galicia-Diez Barroso, Luis David Abeijon Malvaez

    Background: Periodontitis is a chronic inflammatory disease characterized by progressive destruction of the tooth-supporting tissues and may substantially impair oral health-related quality of life (OHRQoL). Although the clinical consequences of periodontitis are well documented, the extent to which disease severity is associated with patient-reported outcomes remains insufficiently understood. This study aimed to evaluate the association between periodontitis severity and OHRQoL and to examine sociodemographic, behavioral, and systemic factors associated with poorer OHRQoL. Methods: A cross-sectional analytical study was conducted among 136 adult patients diagnosed with stage II or stage IV periodontitis at the Periodontology Clinic of Universidad Tecnológica de México (UNITEC). OHRQoL was assessed using the Oral Health Impact Profile for Periodontal Disease (OHIP-14-PD). Sociodemographic characteristics, smoking status, and diabetes mellitus were recorded using a structured questionnaire. Periodontal status was determined through standardized clinical and radiographic examinations. The internal consistency of the OHIP-14-PD was evaluated using Cronbach’s alpha coefficient. Bivariate analyses were performed using non-parametric tests. An exploratory, partially adjusted multivariable linear regression model including sex, marital status, diabetes mellitus, and periodontitis stage was also performed. Results: Stage IV periodontitis was more prevalent than stage II periodontitis (55% vs. 45%). The mean OHIP-14-PD score was 24.9 ± 13.7, and the instrument demonstrated excellent internal consistency (Cronbach’s α = 0.89). Patients with stage IV periodontitis had significantly higher OHIP-14-PD scores than those with stage II disease (30.1 ± 12.4 vs. 18.6 ± 12.6; p < 0.001), indicating poorer OHRQoL. In the bivariate analyses, poorer OHRQoL was also observed among current smokers, participants with diabetes mellitus, those with lower educational attainment, and those with lower socioeconomic status (p < 0.05). In the exploratory partially adjusted model, male sex (β = 4.2; 95% CI: 0.1–8.2; p = 0.042), diabetes mellitus (β = 6.5; 95% CI: 2.1–10.9; p = 0.004), and stage IV periodontitis (β = 4.6; 95% CI: 0.4–8.7; p = 0.031) were associated with higher OHIP-14-PD scores. Conclusions: In this single-center cross-sectional sample, patients with stage IV periodontitis reported higher OHIP-14-PD scores than those with stage II periodontitis. These findings indicate an association within the studied clinical population and should not be interpreted as evidence of a causal effect or as directly generalizable to broader populations. Larger multicenter longitudinal studies including patients across all periodontitis stages are required to confirm the magnitude and external validity of this association.

  • Open Access

    Periodontal Disease and Risk of Osteoradionecrosis in Patients with Head and Neck Cancer Undergoing Radiotherapy: A Systematic Review and Meta-Analysis

    by Gabriela Guadalupe Zambrano Manzaba, Jossue Tarquino Narvaez Guerrero, Luis Chauca-Bajaña, Edwin Geovanny Socasi Dioses, Héctor Alfredo Lema Gutiérrez, Gema Nallely Mendoza Manzaba, Rito Alfonso Salazar Román, Andrea Ordoñez Balladares, Byron Velásquez Ron

    Background: Osteoradionecrosis (ORN) is a severe late complication of radiotherapy for head and neck cancer, associated with impaired bone healing, infection, pain, and exposed bone. Periodontal disease may contribute to ORN by maintaining inflammatory and infectious foci within irradiated tissues with reduced vascularity and repair capacity. Objective: To evaluate whether periodontal disease or poor periodontal status is associated with increased ORN risk in patients with head and neck cancer undergoing radiotherapy. Methods: This systematic review and meta-analysis followed PRISMA 2020 recommendations and was structured according to the PECO framework. Searches were conducted in PubMed/MEDLINE, Embase, Scopus, Web of Science, Cochrane Library, ClinicalTrials.gov, WHO databases, and gray literature. Observational studies involving head and neck cancer patients treated with radiotherapy and reporting periodontal status in relation to ORN were included. Risk of bias was assessed using a domain-based approach. Random-effects models estimated pooled relative effect estimates and ORN prevalence. Results: Six studies were included in the primary association meta-analysis. Periodontal disease was significantly associated with increased ORN risk, with a pooled relative effect estimate of 4.83 (95% CI: 1.96–11.93; p = 0.0006; I2 = 50.4%). Seven studies including 1785 patients and 118 ORN events were included in the prevalence meta-analysis, showing a pooled ORN prevalence of 9% (95% CI: 6–13%; I2 = 78.0%). Conclusions: The findings suggest that periodontal disease or poor periodontal status may be associated with an increased likelihood of ORN in patients with head and neck cancer undergoing radiotherapy. Given the observational nature of the evidence and the moderate between-study heterogeneity, this association should be interpreted cautiously. Comprehensive periodontal assessment and long-term oral surveillance may be considered as components of multidisciplinary care before and after radiotherapy.

  • Open Access

    Mechanical Performance of Milled CAD/CAM Versus 3D-Printed Dental Prostheses: A Systematic Review and Meta-Analysis of Flexural Strength and Fracture Resistance

    by Luis Chauca-Bajaña, Gabriela Guadalupe Zambrano Manzaba, Andrea Ordoñez-Balladares, Rosangela Caicedo-Quiroz, Marcos Daniel Rodríguez Zuleta, Juan Carlos Suarez Palacios, Nayely Teran-Sánchez, Andrea Carolina Sánchez Salcedo, Byron Velasquez Ron

    Background/Objectives: The growing adoption of digital technologies in prosthodontics has led to the widespread use of computer-aided design and computer-aided manufacturing (CAD/CAM) and three-dimensional (3D) printing for dental prostheses. However, differences in mechanical performance, particularly flexural strength and fracture resistance, remain a concern. Objective: To systematically evaluate and compare the flexural strength and fracture resistance of milled CAD/CAM and 3D-printed dental prostheses. Methods: A systematic review and meta-analysis were conducted following PRISMA 2020 guidelines. A comprehensive search was performed across multiple databases, including PubMed, Scopus, Web of Science, and Cochrane Library. In vitro studies comparing milled and 3D-printed prosthetic materials were included. Data extraction and risk of bias assessment were performed independently by multiple reviewers. A random-effects meta-analysis using standardized mean differences (SMD) was conducted. Results: Five studies were included in the meta-analysis for flexural strength. Milled CAD/CAM materials demonstrated significantly higher flexural strength compared to 3D-printed resins (SMD = 3.70; 95% CI: 0.80–6.59; p = 0.012), with substantial heterogeneity (I2 = 93.3%). Fracture resistance results were inconsistent and influenced by individual studies, with sensitivity analyses showing variability in pooled estimates. Overall, the risk of bias was considered low, although some concerns were identified in randomization and blinding. Conclusions: CAD/CAM-milled materials exhibit superior flexural strength, while fracture resistance outcomes remain variable. Although 3D-printed materials may be clinically acceptable, further standardized studies are required to confirm their mechanical reliability.

  • Open Access

    Periodontal Disease and Oral Squamous Cell Carcinoma: A Systematic Review and Meta-Analysis of Risk and Survival Outcomes

    by Gabriela Guadalupe Zambrano Manzaba, Luis Chauca-Bajaña, Carlos Andrés Guim Martínez, Sara Isabel Marcalupo Llerena, Andrea Ordoñez Balladares, Byron Velasquez Ron, Carlos Enrique Cuevas-Suárez, Abigailt Flores-Ledesma, Veronica Natalia Maroto Hidalgo, Gina Fernanda Vásquez Armas

    Background/Objectives: Oral squamous cell carcinoma (OSCC) accounts for over 90% of oral malignancies and remains associated with substantial global morbidity and mortality. Although tobacco and alcohol are established risk factors, they do not fully explain OSCC incidence, highlighting the need to explore additional contributors such as chronic inflammatory conditions. Periodontal disease, characterized by persistent inflammation and microbial dysbiosis, has emerged as a plausible factor in oral carcinogenesis and tumor progression. To systematically evaluate the association between periodontal disease and the risk of developing OSCC, and to assess the prognostic impact of periodontal disease–related factors, particularly intratumoral Porphyromonas gingivalis, on survival outcomes in patients with OSCC. Methods: A systematic review and meta-analysis were conducted in accordance with PRISMA guidelines and prospectively registered in PROSPERO (CRD420261296479). Comprehensive searches were performed in PubMed, EMBASE, Web of Science, Scopus, the Cochrane Library, ClinicalTrials.gov, and World Health Organization regional databases. Case–control studies evaluating OSCC risk and cohort studies assessing survival outcomes were included. Random-effects meta-analyses using inverse-variance models were applied. Heterogeneity was assessed using the I2 statistic, and robustness was evaluated through Hartung–Knapp adjustment, leave-one-out sensitivity analyses, and Trial Sequential Analysis. Results: Five case–control studies were included in the etiological analysis. Periodontal disease was significantly associated with an increased risk of OSCC (pooled OR = 3.17; 95% CI: 1.94–5.21), with moderate heterogeneity (I2 = 58.7%). Two cohort studies were included in the prognostic analysis. High intratumoral expression of P. gingivalis was significantly associated with poorer overall survival (pooled HR = 2.15; 95% CI: 1.33–3.47), with no detected heterogeneity (I2 = 0%). Conclusions: Periodontal disease is strongly associated with an increased risk of OSCC, and intratumoral P. gingivalis appears to be an adverse prognostic marker. These findings underscore the relevance of periodontal inflammation and microbial factors across the OSCC continuum, from carcinogenesis to clinical outcomes, and support their consideration as potential targets for risk stratification and prevention strategies.