|Year : 2022 | Volume
| Issue : 1 | Page : 88-99
Evidence of oral health intervention during pregnancy for spontaneous preterm birth reduction: An integrative review
Cristina Dutra Vieira1, Andreza Nayla de Assis Aguiar2, Camilla Aparecida Silva de Oliveira Lima3, Zilma Silveira Nogueira Reis4
1 Health Informatics Center, Faculty of Medicine, Universidade Federal de Minas Gerais, Minas Gerais, Brazil
2 Department of Preventive Veterinary Medicine, Faculty of Veterinary Medicine, Universidade Federal de Minas Gerais, Minas Gerais, Brazil
3 Health Informatics Center, Faculty of Dentistry, Universidade Federal de Minas Gerais; Newton Paiva University Center, Dentistry School, Minas Gerais, Brazil
4 Informatics Center in Health, Faculty of Medicine, Universidade Federal de Minas Gerais, Minas Gerais, Brazil
|Date of Submission||19-Jan-2021|
|Date of Acceptance||08-Jun-2021|
|Date of Web Publication||04-Jan-2022|
Cristina Dutra Vieira
Faculty of Medicine, Federal University of Minas Gerais, Av. Professor Alfredo Balena, 190, Funcionários, Belo Horizonte, Minas Gerais
Source of Support: None, Conflict of Interest: None
Oral health care is critical for overall well-being, which is associated with better obstetric outcomes. The aim of the present integrative review was to assess scientific reports to support the planning of effective oral health interventions to prevent preterm birth (PTB) and low birth weight (LBW), as a secondary target. Seven bibliographic bases were searched from 2013 to 2018. Studies including oral health interventions during antenatal care with measurable impact on PTB or LBW reduction were searched. Sixteen studies were included. The heterogeneity in the population of pregnant women, and the types of oral intervention as well as the lack of accurate gestational ages, made it difficult to summarize the evidence. Despite the early intervention in high-risk groups, there was not enough evidence to support a significant reduction in PTB rates. There was some evidence that untreated periodontal disease in pregnancy was associated with LBW. This review did not provide strong evidence that preventive oral interventions during pregnancy had a measurable impact on spontaneous PTB reduction. However, further research is needed to clarify the impact of oral health interventions on the general pregnant women population or on those with a high risk of PTB and LBW.
Keywords: Adult periodontitis, low birth weight, oral health, preterm birth, review
|How to cite this article:|
Vieira CD, de Assis Aguiar AN, de Oliveira Lima CA, Nogueira Reis ZS. Evidence of oral health intervention during pregnancy for spontaneous preterm birth reduction: An integrative review. J Oral Res Rev 2022;14:88-99
|How to cite this URL:|
Vieira CD, de Assis Aguiar AN, de Oliveira Lima CA, Nogueira Reis ZS. Evidence of oral health intervention during pregnancy for spontaneous preterm birth reduction: An integrative review. J Oral Res Rev [serial online] 2022 [cited 2022 Jan 28];14:88-99. Available from: https://www.jorr.org/text.asp?2022/14/1/88/334833
| Introduction|| |
Adverse pregnancy outcomes, including premature birth (before 37 weeks of gestation, represent a public health problem in both developed and developing countries. According to the World Health Organization, every year 30 million newborns are at risk due to preterm birth; 2.5 million die during the first 28 days of life and two-third of them were born prematurely. In Brazil, the Ministry of Health stated that prematurity represented 11.2% of live births. Brazil is one of the ten countries with the highest number of preterm births. However, there are a multitude of reasons for preterm delivery, it is clinically classified as spontaneous or interventional due to life-threatening pregnancy situations. Preterm prevention strategies require comprehensive approaches since public policies, educational programs, lifestyle adjustments, and actions improve the quality of obstetric health care. Among these, oral diseases have been reported as a risk factor in preterm birth and low birth weight (LBW).
Oral health is a key factor in overall health and WHO estimates that oral diseases affect 3.58 billion people worldwide. Oral diseases, especially progressive periodontal disease (PD), can cause the destruction of the alveolar bones of the jaw and other supporting tissues., Besides its effect on oral tissues leading to tooth loss, PD has been linked to systemic diseases including cardiovascular disease, diabetes mellitus, and preterm LBW. PD is a group of infectious disorders with a high prevalence in the global population. It can consist of gingivitis (reversible gingival inflammation) and periodontitis (gingivitis with gingival recession accompanied by loss of connective tissue and alveolar bone). Studies have investigated the occurrence of PD during pregnancy, yielding a wide variation in prevalence. Pregnant women with PD have been reported to be at increased risk of an adverse pregnancy outcome; however, the studies are controversial. PD during pregnancy and the impact of oral hygiene and professional treatment as measures to reduce preterm birth rates are scarcely discussed or investigated. Considering the overall paucity of evidence regarding the effect of antenatal interventions in oral health on prematurity reduction, this integrative review aims to access scientific reports to support the planning of effective interventions in oral health to prevent spontaneous prematurity or LBW rates.
| Methods|| |
An integrative review on evidence to respond to the primary research question: Are interventions to promote oral health during antenatal care associated with preterm birth (PTB) and LBW prevention? In an attempt to describe the background, objectives, design, methodology, and organization of this integrative review, it was online registered in Protocols. IO under DOI number dx. doi. org/10.17504/protocols. io. yyzfxx6. The complete search strategy is described in an additional file [Supplementary Material 1]. The databases searched included Spanish, Portuguese and English languages and were 'Bibliografía Nacional en Ciencias de la Salud', 'Biblioteca Virtual em Saúde, Indice Bibliográfico Espanhol de Ciências da Saúde', 'Literatura Latino-americana e do Caribe em Ciências da Saúde', 'Scientific Electronic Library Online', 'Segunda Opinião Informativa SOF', and 'MEDLINE via PubMed'. The literature study covered the last 5 years, until July 10, 2018. The review process was limited to this period of time to aim for latter evidences.
Four reviewers screened the search output to identify potentially relevant studies, analyzing only titles and abstracts using the following predetermined eligibility criteria: human pregnancy, oral or dental health, oral health education, health promotion, and premature birth outcome. During the selection process, the prioritized studies were clinical trials (randomized/non-randomized/after-before), systematic reviews, and case–control studies. The exclusion criteria were nonhuman pregnancy, opinion of a specialist, literature review or recommendations without scientific evidence, no clinical approach, protocols of research without results, and no intervention in oral health.
Extraction and data analysis
Variables were extracted from all the selected and fully read studies, as planned in the review protocol. The primary outcome was the reduction in spontaneous PTB or LBW rates. The results were summarized according to the characteristics of the population (scenario), the moment of pregnancy for the approach, protocols of the PDs diagnosis, modality of the intervention, and the type of treatment or oral hygiene measures. Two senior specialists conducted the review process. They read the articles to confirm they were appropriate for the review and to decide between studies that disagreed. Standard data selection, extraction, and summarization were supported by software.
| Results|| |
Bibliographic searching retrieved a total of 317 articles. There were 95 full-text articles that were assessed for eligibility, 79 of which were deemed ineligible [a descriptive summary of the 79 full-text excluded studies is showed on Supplementary Material 2], and 16 met the inclusion criteria. [Figure 1] presents the flow of identification, selection, and inclusion of studies, according to the PRISMA diagram. No clinical approach or a lack of intervention during pregnancy was the primary reason for excluding the 79 studies (83.2%).
Seven studies selected for this review (43.8%) were systematic reviews,,,,, or meta-reviews., Of the nine primary studies, eight were clinical trials with,,,,,,, or without randomization,, of the intervention and one was an experimental study.
Characteristics of the reviewed studies
[Table 1] summarizes the reviewed studies concerning the pregnancy scenario, schedule of intervention, and follow-up, as well as the study design and the quality of clinical data source.
Due to the impact of factors beyond the study design on the external validity of outcomes, the local health attention scenario, eligibility criteria, and the quality of clinical data are also detailed. The reports evaluated oral health interventions in different profiles of pregnant women, with varying levels of PD or gingivitis. Some of the studies enrolled pregnant women receiving prenatal care at a reference hospital,,, without the exclusion of maternal or fetal disease or only under vaginal delivery. Most of the reports studied selected samples with moderate or severe disturbances in their oral health, PD or gingivitis, excluding maternal comorbidities.,,,,, Other studies were systematic reviews, with a heterogeneous scenario or a lack of sufficient details.,,,,, In most of the primary studies (62.5%), the gestational age (GA) was not confirmed with an obstetric ultrasound. Standardized reports of birth weight measurements were only mentioned in Soroye et al.
Characteristics of the performed periodontal treatment
Concerning the intervention in PD, [Table 2] presents results based on the time of intervention: ≤20 weeks of gestation, >20 weeks of gestation, or time not described. The criteria for PD diagnosis and the mode of treatment are highlighted.
|Table 2: Outcomes and results according to the moment of intervention, the consideration of oral hygiene measures, and the diagnosis and treatment of periodontal diseases|
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Only six of the studies (37.5%) clarified that there was an intervention at less than 20 weeks of gestation.,,,, In five of these studies, oral hygiene education was offered and two mentioned that dental supplies (toothbrush and toothpaste) were also provided., One report added a structured and extensive questionnaire to investigate oral hygiene habits. The indices used to diagnose PDs varied among the six studies, ranging from one to three. Two studies used additional methods to diagnose the level of PD: detection of C-reactive protein (CRP) levels in blood samples, and the association among genes recovered from saliva and the obtained results. All but one study stated that periodontal scaling and root planing (PSRP) was the nonsurgical treatment offered. Despite this apparent homogeneity in treatment, a different number of dental visits was observed among the studies. In four studies,,,, the periodontal treatment resulted in an improvement in the oral health indices. One study did not demonstrate any oral health progress, but it is important to emphasize that no local intervention was applied. Another study showed that unsuccessful periodontal treatment group deteriorated their periodontal status. There were five studies that investigated intervention after 20 weeks of gestation.,,,, Oral hygiene education was part of the treatment in almost all studies, except for two systematic reviews of randomized controlled trial RCTs,, which included works that were not mentioned in the procedure. The studies cited several indices to achieve PD diagnosis. Two studies included the investigation of inflammatory mediators., The number of dental visits to perform treatment was also dissimilar among studies., All studies stated that periodontal treatment consisted of PSRP. In three of the five studies, the periodontal treatment resulted in an improved oral health status, and the remaining two did not provide the results., The time of oral health intervention was not mentioned in the last 5 of 16 studies.,,,, A miscellaneous group of indicators, combined or alone, were used to diagnose and treat PD. A single study provided some evidence about the existence of potential factors that influence the severity of PD, such as who gave the treatment (e.g., periodontists, hygienists, and therapists). The results of periodontal treatment were not clearly demonstrated in two reports., The other three studies,, demonstrated that treatment was safe and effective during pregnancy, enhancing oral and general health conditions.
Subgroups of the reviewed studies considering the moment of oral health intervention
Subgroups of early, late, or unspecified temporal approaches are organized in [Table 3] to clarify the lessons learned when planning antenatal interventions in oral health to reduce prematurity and LBW.
|Table 3: Obstetric outcomes, limitations on the evidence, and the lessons learned for planning oral health intervention during prenatal care|
Click here to view
Subgroup one is comprised four studies,,, where approaches, treatment, or prophylaxis were introduced at less than 20 weeks of gestation in women with a higher than normal severity of PD. Even with the early intervention in high-risk groups, there was not enough evidence of a significant reduction in PTB rates. However, there was little evidence that untreated PD in pregnancy was associated with LBW. Regarding the relevance of early intervention by modulating levels of inflammatory mediators, the adverse pregnancy outcome was lower when traced by the CRP. However, the following RCT in a reference center for pregnant women had no success in demonstrating that the reduction of periodontal inflammation, up to the second trimester of gestation, affected preterm birth LBW (PTLBW) rates. Subgroup two is comprised studies which investigated late interventions (>20 weeks of gestation) and the evidence is inclusive concerning the effect in PTB and LBW.,,, Inconclusive outcomes are not useful for planning oral health approaches. However, the systematic review of Boutin et al. stated that pregnant women with PD should receive periodontal therapy, adding that PTB is reduced by the use of an antimicrobial mouth rinse. Subgroup three includes studies that fail to clarify the time of oral antenatal intervention, standardize the severity of the PD, state the source of variables (e.g., GA), or state confounders (e.g., obstetric risks associated with adverse results of pregnancy). Systematic reviews that do not specify the time of intervention, despite the low quality of evidence, suggest that periodontal treatment may reduce PTB and LBW.,,, Concerning high-risk PTB populations, when periodontal treatment was properly performed and adequate criteria for periodontitis were used, the elimination of PD was potentially an effective way to prevent PTB and LBW.
| Discussion|| |
Strengths and limitations of the study
The strength of this study was the vast critical review of the impact of oral health treatment during pregnancy and the possible improvements in PTB and LBW rates. This integrative review contains several periodontal treatments, such as oral health education and the use of a mouth rinse, along with surgical and nonsurgical therapy. Our integrative review was registered online (Protocols. IO) and was performed by following a strict methodological approach. The limitations of our study are in part due to the primary articles. The source of GA calculation at birth and the number of periodontal indices to diagnose PD were not carefully considered in these studies and could be considered potential sources of prejudice in the analyses. There is a gap between these indices to diagnose PD and obstetric outcomes. In the present review, it was difficult to establish a correlation between them due to the large number of indices used and the variability in the combinations. This review should be interpreted with some caution due to these limitations.
Periodontal therapy, pregnancy, and neonatal outcomes
Periodontal therapy during pregnancy seems to decrease periodontal inflammatory status by providing a healthier oral environment.,,,, In addition, treatment was considered safe and effective if performed during pregnancy.,,,, Nonetheless, the reduction of periodontal inflammation itself and the decreasing of all PD indices,,,,,,, were not enough to affect the neonatal outcomes, although untreated PD was associated with higher LBW levels. Another perspective came from a study performed in the first half of pregnancy. The authors found an interesting relation among PD treatment failure, spontaneous PTB, and a gene associated with inflammatory response. Despite the small sample size, the authors encouraged periodontal therapy in pregnant women.
The principle of periodontal treatment, including non-surgical therapy, is to re-establish and maintain periodontal health and function. There was a consensus about PD treatment among studies that specified the time of oral health interventions. PSRP was the prevailing treatment among studies whose oral interventions were performed before,,,, and after 20 weeks,,,, of gestation. The study of Khairnar et al. included an evaluation of CRP levels, in addition to periodontal indices at baseline and after delivery. Their results demonstrated that a reduction of CRP values after delivery only occurred for the treatment group who received PSRP. The study of Aljateeli et al. demonstrated that PSRP led to a considerable reduction in PD and also eliminated the need for surgery for one patient. Hence, PSRP was considered a very important initial phase of periodontal therapy. In studies where the time of oral health intervention was not defined, several treatments were provided, sometimes a combination of treatments, including oral surgery. Among these reports, some mentioned the use of topical or systemic antimicrobial therapy.,,,,
Oral health preventive measures and pregnancy
Oral health during pregnancy is receiving more attention and is being recognized as an integral part of preventive health care for pregnant women and their newborns. Prevention measures include providing information promoting oral health, which should be incorporated into prenatal visits. Most studies in this review mentioned preventive measures, such as oral hygiene instructions/education, including a video. Six systematic or meta-reviews did not homogeneously inform about these procedures to the control and test groups. Only Khairnar et al. did not mention their approach. Some reports mentioned a statistically significant decrease in plaque index with one or more sessions of oral health education.,,,, Several indices, both associated and unassociated, were used to diagnose PD. Clinical attachment loss and bleeding on probing were the most commonly used indices among the studies that specified the time of intervention (37.5%). As this is an integrative review congregating primary and secondary studies, a multiple publication bias of research is possible. Notwithstanding, we did not consider excluding primary studies, even those used in systematic reviews, because they provided detailed analyses. For instance, Pirie et al. was included by Rangel-Rincón et al., Iheozor-Ejiofor et al., da Silva et al., and Schwendicke et al. Similarly, including systematic reviews may present some intersection of the primary base of the articles. Performance bias related to a lack of random allocation of intervention, pilot analysis, and small samples,,, as well as fragile methodology based on interview is to be expected.
Periodontal therapy and spontaneous prematurity
PTB is considered a multifactorial disorder with different causes in assorted scenarios. It is a big challenge, the rate is growing globally, reflecting racial, ethnic, and socioeconomic disparities, and it is a leading cause of death in children below 5 years of age. In this study, we focused our question on spontaneous prematurity to avoid iatrogenic pregnancy interruptions related to maternal and/or fetal diseases. Many current methods for the diagnosis of prematurity are inadequate, and little is known about how PTB can be prevented. Preterm neonate identification depends on reliable pregnancy dating, which can be challenging in low- and middle-income countries. A lack of concern about the source of GA calculation at birth was present in most of the selected studies. The last menstrual period, early or late ultrasounds, or maturity score references result in uncertainties of 5 to 40 days, directly affecting the rates of prematurity. An early crown–rump length measurement of an embryo, obtained by obstetric ultrasound, currently offers the best due date. However, none of the reports used this consensual reference.
Periodontal therapy and low birth weight
The birth weight is much easier to obtain than GA. We chose this outcome due to the lower uncertainty with this classification. Nevertheless, an LBW newborn needs specific attention to survive. Thirteen articles mentioned LBW or PTLBW outcomes, there was a lack of evidence to support a plan concerning oral health prevention to improve birth outcomes. Specific treatment may reduce the risk of LBW in groups with a high rate of PD disease or for those in poor, rural areas or when chlorhexidine is added to the intervention., In contrast, the use of 0.7 cetylpyridinium chloride to treat PD was not effective in reducing PTB or LBW.
Future studies will need to address various challenges to better understand the impact of poor oral health on pregnancies. For example, the way the severity of PD is classified needs to be addressed. Furthermore, more reliable markers are needed to measure the effectiveness of the different types of intervention. Regarding the outcomes, the impact of oral health promotion during pregnancy for PTB reduction will remain hard to robustly quantify if pregnancy dating continues to be viewed as a trivial task. An early enrolment of pregnant women confirming GA references with an obstetric ultrasound and implementing a thoroughly planned, large RCT that investigates the multifactorial environment of PTB pathogenesis could provide better answers.
This integrative review did not provide conclusive evidence to plan effective interventions in oral health to prevent spontaneous prematurity and LBW occurrence. There remains uncertainty about the best way to approach oral health during pregnancy to prevent PTB. These results did not support the absence of actions that promote oral health during pregnancy since a comprehensive view of integral health is a fundamental element of antenatal care. This review did not provide strong evidence to show that the implementation of preventive oral intervention during prenatal care had a measurable impact on spontaneous PTB reduction or LBW occurrence.
This research was supported by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior-CAPES-Brazil (Process number 88881.172810/2018-01).
This integrative review did not require Ethical approval since it did not collect participants' personal, sensitive, or confidential information. The authors affirm that the manuscript is an honest, accurate, and transparent account of the reported study.
Financial support and sponsorship
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior-CAPES-Brazil (Process number 88881.172810/2018-01).
Conflicts of interest
There are no conflicts of interest.
Group 1: Education (“Educação em Saúde” OR “Educação em Saúde Bucal” OR “Promoção da Saúde” OR “Promoção em Saúde” OR “Educación en Salud” OR “Educación en Salud Dental” OR “Promoción de la Salud” OR “Health Education” OR “Health Education, Dental” OR “Health Promotion”)
Group 2: Pregnant Women (Gestantes OR “Resultado da Gravidez” OR “Recém-Nascido de Baixo Peso” OR “Nascimento Prematuro” OR “Recém-Nascido Pequeno para a Idade Gestacional” OR “Idade Gestacional” OR “Mujeres Embarazadas” OR “Resultado del Embarazo” OR “Recién Nacido de Bajo Peso” OR “Nacimiento Prematuro” OR “Recién Nacido Pequeño para la Edad Gestacional” OR “Edad Gestacional” OR “Pregnant Women” OR “Pregnancy Outcome” OR “Infant, Low Birth Weight” OR “Premature Birth” OR “Infant, Small for Gestational Age” OR “Gestational Age”)
Group 3: Periodontitis (Periodontite OR “Doenças Periodontais” OR “Higiene Bucal” OR “número de dentes” OR Periodontitis OR “Enfermedades Periodontales” OR “Higiene Bucal” OR Periodontitis OR “Prepubertal Periodontitis” OR “Periodontal Diseases” OR “Periodontal health” OR “Periodontal treatment” OR “Periodontal therapy” OR “Number of teeth” OR “Oral Hygiene”)
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[Table 1], [Table 2], [Table 3]