On the relationship between gingival biotypes and gingival thickness in young Caucasians

Comparison of gingival thickness by CBCT versus transgingival probing and estimation of cut-off values for gingival phenotype - A cross-sectional study in adults

AIM

Gingival phenotype (GP) is regarded as a valuable indicator for forecasting the probability of attaining favourable aesthetic and functional results with orthodontic treatment. This study aimed to investigate the accuracy and reproducibility of cone beam computed tomography (CBCT) for assessing gingival thickness (GT) in both arches compared to the transgingival probing method. The secondary objective was to determine the optimal cut-off values for GT using CBCT.

METHODS

This cross-sectional study was conducted where GP was determined based on the probe transparency method (TRAN). The GT measurements were obtained by both methods at 2mm from the free gingival margin (FGM) for all teeth anterior to the first molar. The data was statistically analysed using intraclass correlation coefficient (ICC), Bland-Altman plots, and receiver operating characteristic (ROC) curves. The statistical significance level was set at a P-value<0.05.

RESULTS

The study included 60 subjects (1200 teeth). The mean GT in both the maxillary (1.14±0.17mm) and mandibular (0.94±0.15mm) arches was significantly greater (P<0.05) for the transgingival probing method than for the CBCT method. As shown in the Bland-Altman plot, the bias between the two methods was greater in the maxillary jaw (0.060; 95% CI: 0.044 to 0.076) and in individuals with a thick GP (0.096; 95% CI: 0.082 to 0.109). The optimal values for GT measurements were 1.15mm for the maxillary jaw, 1.02mm for the mandibular jaw, 1.02mm for males, and 1.09mm for females.

CONCLUSIONS

CBCT exhibited notable precision in diagnosing GT, while demonstrating minimal disparities compared to the conventional transgingival probing technique, particularly evident in thin GPs, and in the mandibular dental arch. The constraints associated with the utilization of CBCT were observed in the maxillary arch and in cases with thick GP.

Gingival phenotype classification by visual and probe visibility assessments: Relationship with thickness and probe design

BACKGROUND

This study investigated the agreement among dentists in classifying gingival phenotype (GP) through periodontal probe visibility (PPV) assessment with various probe types and the visual method. Additionally, the relationship between GP classifications and gingival thickness (GT) was evaluated.

METHODS

Photographs were taken with standard periodontal probe (SPP), color-coded periodontal probe (CCPP) tips in white, green, and blue, as well as metal phenotype probe (MPP) tips in gray and black. Evaluators (periodontist, periodontics resident, endodontics resident, dental student) assessed the photographs and classified the GPs. GT was measured by trans gingival probing.

RESULTS

Visual method showed poor to fair agreement to classify GP. The lowest agreement regarding PPV was noted with white-tipped CCPP. The highest agreement in singular PPV was observed with CCPP blue (κ = 0.932), followed by CCPP green (κ = 0.791), MPP black (κ = 0.783), SPP (κ = 0.730), and MPP gray (κ = 0.690). Combined PPV data revealed fair to moderate agreement with CCPP and moderate to substantial agreement with MPP in GP classification. The corresponding GT to different GP classifications based on combined PPV were comparable. The agreement between SPP and CCPP in classifying non-thin phenotypes was 89.8%, while the agreement between SPP and MPP was 75.4%. Based on PPV, no significant GT cutoff value was found to distinguish between thin and non-thin phenotypes.

CONCLUSION

Determining a precise GT that guarantees the visibility of a given probe can be difficult when evaluating GP. Regardless of the type of probe, the PPV method has a high potential for misclassifying GP, despite having an acceptable agreement.

PLAIN LANGUAGE SUMMARY

Gingival phenotype (GP) is constituted by thickness of the gums and width of keratinized tissue around teeth. Direct visual evaluation or evaluating a periodontal probe's visibility beneath gums are established techniques to classify gingival phenotype. This study investigated how dentists classify GP using visual assessments and different types of periodontal probes, while also exploring the relationship between GP classifications and gingival thickness. Results showed varied agreement among dentists in classifying GP, with lower agreement observed when using certain types of probes, notably the white-tipped phenotype probe. The highest agreement was found with the blue phenotype probe. Data from periodontal probe visibility assessments indicated fair to moderate agreement with certain probes, suggesting some inconsistency in classification methods. Interestingly, GP classification with visual assessments or probes did not correlate with gingival thickness, which may highlight the importance of considering both factors in clinical practice. These findings underline the need for attention when relying solely on visual assessments or specific probe types for accurate GP classification.

Prevalence of the Gingival Phenotype in Adults and Associated Risk Factors: A Systematic Review of the Literature

The relevance of assessing the gingival phenotype prior to the initiation of periodontal, orthodontic, or prosthetic therapy has been clearly demonstrated. However, publications on this subject are either old or concerned with the means of assessing the gingival phenotype or the main factors likely to modify it. The main objective of this systematic review of the literature was therefore to investigate the prevalence of different gingival phenotypes in adults in good general health and with a healthy periodontium. A systematic review of the literature was performed following the guidelines of PRISMA recommendations using an electronic search strategy on four databases (PubMed, Scopus, Cochrane Library, and Embase) complemented by a manual search. Three independent authors were involved in study selection, data extraction, and bias assessment. Results: Of 807 articles, 17 of them, published between 2012 and 2023, involving 3277 subjects from 11 countries and 9766 dental sites, fulfilled the inclusion criteria. The prevalence of the gingival phenotype could not be determined at the level of an individual or a dental arch because all the publications assessed this phenotype only at the level of certain dental sectors, and were not chosen at random. The maxillary central incisors and maxillary or mandibular first molar sectors were associated with a high and thick gingival phenotype, independently of the dental morphology, gender, and age of adult subjects. Furthermore, in these regions, this gingival phenotype tended to be associated with a thick vestibular bone table. In contrast, maxillary and mandibular incisors and premolars more often had a thin gingival phenotype. For other teeth, the results were less conclusive. It is important not to rely solely on the overall appearance of the dentition but to independently assess the thickness and height of the gingiva at each dental site requiring intervention. Finally, this study highlights a key point, namely the need for further longitudinal studies to determine the prevalence in healthy adults. For practicality and feasibility reasons, these studies should be designed according to therapeutic needs, dental sector by dental sector, and within homogeneous source populations. PROSPERO registration: CRD 42023392602.

An evaluation of gingival phenotype and thickness as determined by indirect and direct methods

OBJECTIVES

To evaluate gingival phenotype (GP) and thickness (GT) using visual, probing, and ultrasound (US) methods and to assess the accuracy and consistency of clinicians to visually identify GP.

MATERIALS AND METHODS

The GP and GT of maxillary and mandibular anterior teeth in 29 orthodontic patients (mean age 25 ± 7.5 years) were assessed using probing and US by a single examiner. General dentist and dental specialist assessors (n = 104) were shown intraoral photographs of the patients, including six repeated images, and asked to identify the GP via a questionnaire.

RESULTS

An increasing trend in GT values of thin, medium, and thick biotype probe categories was found, though this was not statistically significant (P = .188). Comparison of probing method to determinations of GT made by US yielded slight agreement (κ = 0.12). Using the visual method, assessors' identification of the second GP determination ranged from poor to moderate agreement (κ = 0.29 to κ = 0.53).

CONCLUSIONS

The probe method is sufficient in differentiating between different categories of GP. However, further research is required to assess the sensitivity of the probe method in recognizing phenotypes in the most marginal of cases. Assessors using the visual method lack the ability to identify GP accurately and consistently among themselves.

Revisiting the measurement of keratinized gingiva: a cross-sectional study comparing an intraoral scanner with clinical parameters

PURPOSE

The aim of this study was to investigate the relationships between gingival thickness (GT) and keratinized gingiva width (KGW), papilla height (PH), and crown ratio (CR) by employing transgingival probing and an intraoral scanner (IOS).

METHODS

This cross-sectional study examined 360 maxillary anterior teeth from 60 patients. GT was assessed using transgingival probing with an endodontic spreader. KGW, CR, and PH were measured using an IOS. One-way analysis of variance, the Student's t-test, and Spearman correlation coefficients were employed for statistical analysis.

RESULTS

Higher GT was significantly associated with thinner KGW in the central region (P=0.019). There was no statistically significant difference in GT between teeth (P=0.06). PH was lower in lateral teeth than in canines (P=0.047), with a PH of 2.99 mm in lateral teeth. The KGW was narrower in canines than in central teeth (P=0.007). A moderate correlation was observed between KGW and PH in the central region (P=0.01), while a weak negative correlation was found between KGW and CR (P=0.043).

CONCLUSIONS

A moderate negative correlation was found between GT and KGW, as well as between PH and KGW in central teeth. In contrast, a weak negative correlation existed between CR and KGW. The PH (2.99 mm) was lower in lateral teeth than in canines. The traditional paradigm, which suggests a positive correlation between KGW and GT, was re-evaluated by measuring KGW using an IOS.

Injectable Platelet-Rich Fibrin and Microneedling—A Non-Surgical Approach for Gingival Augmentation: A Randomized Controlled Clinical Trial

Aim:

The present study aimed to assess the efficacy of combining microneedling (MN) and injectable platelet-rich fibrin (i-PRF) administration with i-PRF alone in augmenting the thickness of gingiva to manage thin periodontal phenotype.

Methodology:

The clinical trial involved 36 patients who were diagnosed with thin periodontal phenotype. They were randomized under two groups: MN + i-PRF versus i-PRF alone, carried out as a split-mouth trial. One quadrant was treated only with i-PRF delivery through the gingival sulcus, while the contralateral side was treated with MN and i-PRF in 3 sessions at 10-day intervals. The primary parameter measured was the thickness of the gingiva, at baseline and 3 months following therapy. Statistical analysis was performed using the Mann-Whitney U test. Wilcoxon’s signed ranking test for inter-group and intra-group analysis, respectively.

Results:

The study results showed a significantly greater increase in gingival thickness (GT) in sites where both MN and i-PRF injection was done, compared to i-PRF alone, with a p value of .04.

Conclusion:

Both treatment modalities showed improvement in GT, being a minimally invasive alternative for mucogingival surgery. Adjunctive MN was found to be more beneficial than i-PRF alone. However, further research should be carried out to address the drawbacks of the study and for a better understanding of this novel approach.

Current landmarks for gingival thickness evaluation in maxillary anterior teeth: a systematic review

OBJECTIVES

To identify and report the current landmarks used for measuring gingival thickness (GT) in healthy maxillary anterior teeth.

MATERIAL AND METHODS

The protocol of this Preferred Reporting Items of Systematic Reviews and Meta-Analyses (PRISMA) 2020-compliant systematic review was registered in PROSPERO. A literature search was conducted to identify articles that met the eligibility criteria published up to 2022. The methods of assessing gingival thickness and the landmarks adopted on the studies were described. Primary outcomes were identified, and the frequency of reporting in the selected articles was calculated. Additionally, risk-of-bias assessments were performed for individual articles.

RESULTS

Fifty-eight articles (34 with low risk of bias and 24 with medium risk of bias) were selected. A total of 3638 individuals had their gingival thickness measured. Thirty-nine different landmarks were adopted in the studies. Fifty-six articles with 22 landmarks were included in the meta-analysis. A higher heterogeneity was found between the studies (GT ranged from 0.48 to 2.59 mm, mean GT 1.074; 95% CI: 1.024-1.104). The 3 most used landmarks were 2 mm from gingival margin (10 studies, mean GT 1.170 mm, 95% CI: 1.085-1.254), bone crest (9 studies, mean GT 1.01 mm; 95% CI: 0.937-1.083), and cemento-enamel junction (7 studies, mean GT 1.172 mm; 95% CI: 1.105, 1.239).

CONCLUSIONS

Within the limits of this study, a large heterogeneity in GT was found, and there was no consensus on the ideal landmark for GT measurement.

CLINICAL RELEVANCE

The landmark 2 mm from gingival margin, located at attached gingiva, can be used for GT measurement by clinical and image-based devices. This is an important step for a quantitative instead of a qualitative evaluation of phenotypes.

Gingival Phenotype Changes and the Prevalence of Mucogingival Deformities during the Early Transitional Dentition Phase-A Two-Year Longitudinal Study

Thin gingival phenotype (GPh) may contribute to periodontal tissue breakdown and recession development. Thus, the early identification of thin GPh in children can allow proper preventive care and the identification of children at risk during orthodontic treatment. The present long-term study aimed to monitor GPh changes, i.e., thickness (GT) and width of attached gingiva (AGW) during the early transitional dentition phase, as well as its potential associations with the mucogingival deformities. Materials and Methods: 83 systematically healthy children were examined twice with an interval of 2 years. Probing depth, GT and AGW at mandibular incisors, vestibular depth, type of lower lip frenum attachment and mucogingival defects were recorded. Results: 95.2% of participants at baseline and 93.9% at 2-year examination expressed thin GPh. During the transition from the deciduous to permanent dentition, GT and AGW declined, but the GT of permanent incisors already erupted at the baseline examination increased in the observation period. Conclusions: Gingival phenotype undergoes changes in the early transitional dentition phase. In spite of the thin gingival phenotype, only single pseudo-recessions and primary shallow vestibule were noticed.

Gingival phenotype distribution in young Caucasian women and men - An investigative study

OBJECTIVES

To evaluate the relationship between gingival phenotype and tooth location based on selected index teeth ("Ramfjord") and assess possible differences between women and men.

MATERIAL AND METHODS

Thirty-six women and 20 men voluntarily participated in this investigation with an average age of 23 years (min: 19; max: 37). Gingival phenotypes (GP) were assessed by transparency of a periodontal probe through the buccal gingival margin.

RESULTS

A comparable and similar GP on all index teeth was only found in seven out of the 56 subjects, that is, thin or thick only: Five participants (three male/two female) showed a uniform and constantly thick and two females a constantly thin GP. While the majority of molars (94.6%; p = 0.006) showed a thick GP, premolars (61.6%; p = 0.09) as well as incisors (70.5%; p = 0.046) were predominantly categorized as thin. In addition, significantly thicker GP was in general observed for maxillary teeth (p = 0.001) but without differences between genders (p = 0.722).

CONCLUSION

No constant GP can be expected within one dentition. The use of the "Ramfjord teeth" may serve as a quick overview and reliable method to screen GP distribution.

Are colored periodontal probes reliable to classify the gingival phenotype in terms of gingival thickness?

BACKGROUND

This cross-sectional study assessed the potential of colored periodontal probes (CPP) to classify gingival phenotype in terms of gingival thickness (GT).

METHODS

Buccal GT in 3 anterior teeth in each of 50 patients was measured by transgingival sounding and classified by 3 different methods by 8 examiners. Specifically, the diagnostic potential of visual judgement and transparency of a standard periodontal probe (SPP) to discriminate thin and thick gingiva, and of CPP to discriminate thin, medium, thick, or very thick gingiva was assessed.

RESULTS

GT ranged from 0.57-2.37mm. Using CPP resulted in a medium judgement in 87% of the cases, on average, and only between 1-10 cases/examiner were judged as thick or very thick. Considering 1mm GT as relevant cut-off value, all methods showed a high positive predictive value (≥0.82) to identify thick cases, but also a high false omission rate (≥0.73) indicating that many cases classified as thin were actually thick. Further, 88% of the cases being ≤1mm, were not classified as thin with CPP; this was inferior to SPP, for which, however, still 64% of the cases being ≤1mm thick were wrongly classified. The highest, yet moderate agreement among examiners was achieved by SPP (κ = 0.427), while visual judgement and CPP showed only fair (κ = 0.211) and slight agreement (κ = 0.112), respectively.

CONCLUSION

Using CPP resulted in most of the cases in a medium judgement. It seems that CPP cannot distinctly discriminate between "thick" and "very thick" cases and fails to capture the thin high-risk cases. This article is protected by copyright. All rights reserved.

Prevalance and clinical characteristics of gingival recession in Greek young adults: A cross-sectional study

OBJECTIVE

The current cross-sectional study aimed to investigate the prevalence of gingival recession (REC) in a sample of young individuals. In addition, the association with several risk factors was examined.

MATERIALS & METHODS

A 104 subjects, aged 18-30 years old, were randomly enrolled in the study. Participants were requested to fill in a simple structured questionnaire in order to provide information on dental hygiene habits, educational level, smoking and history of orthodontic treatment. Afterwards, all the included individuals were subjected to a thorough clinical periodontal examination including gingival recession (REC), gingival biotype, plaque levels and gingival bleeding index (GBI) assessment.

RESULTS

The mean prevalence of REC in the studied population surpassed 50% with an equal distribution among females and males. The most common teeth associated with REC were the lower left canine and left 1st premolar. Among the examined variables, only the bleeding index was found to be associated with the presence of REC.

CONCLUSIONS

Gingival recession was a prevalent condition among young individuals. Gingival inflammation was found to be the most significant factor affecting the incidence of REC.

Is There an Association between the Gingival Phenotype and the Width of Keratinized Gingiva? A Systematic Review

The concept of gingival phenotype and width of keratinized gingiva influencing the diagnosis and treatment in the periodontal scenario is relatively new. Soft and hard tissue dimensions of oral tissues are considered essential parameters in daily clinical practice. Factors such as the biotype category and the width of the keratinized gingiva help dentists seek the perfect therapy plan for each patient to achieve long-term stability of periodontal health. Several methods have been proposed to categorize phenotypes and each phenotype is characterized by various clinical characteristics. This review aims to discuss the possible association between the gingival phenotype and the width of keratinized gingiva along with the results appeared. After a rigorous search in major electronic databases, the results of the included studies indicated that the width of keratinized gingiva seems to be associated with the periodontal phenotype, with thick biotypes being characterized by a more pronounced keratinized gingival width. However, the heterogeneity of the included studies did not allow to make a conclusion about a direct relationship.

Gingival phenotype assessment methods and classifications revisited: a preclinical study

Objective

To compare gingival phenotype assessment methods based on soft tissue transparency on different backgrounds and assessor experience levels.

Methods

For this purpose, 24 gingival specimens were retrieved from pig jaws with tissue thicknesses from 0.2 to 1.25 mm. Three methods were assessed: periodontal probe PCP12 (thin/thick), double-ended periodontal probe DBS12 (thin/moderate/thick) and colour-based phenotype probe CBP (thin/moderate/thick/very thick). Each sample was photographed with each probe underneath and categorized whether the probe was visible or not using different coloured backgrounds. To measure experience level influence, dentists, dental undergraduate students and laypersons (n = 10/group) performed the evaluation.

Results

PCP12 probe showed a threshold between 0.4 and 0.5 mm. To distinct between thin and moderate thick gingiva, a comparable range for DBS12 was found while moderate thickness was between 0.5 and 0.8 mm and for thick above 0.8 mm. CBP also showed a comparable threshold of 0.5 mm for thin versus moderate as compared with the other methods; above 0.8 mm, predominantly a very thick tissue was measured. In general, the background colour had a minor impact on PCP12 and DBS12, and investigator experience showed no clear influence on GP assessment.

Conclusion

Based on probe transparency and within the limitation of a preclinical study, we suggest GP differentiation into three entities: thin (< 0.5 mm; high risk), moderate (0.5–0.8 mm; medium risk) and thick (> 0.8 mm; low risk).

Clinical relevance

All three GP assessment methods are easy to perform and seem to have a high predictive value with a three entities classification for DBS12 and CBP.

Correlation analysis of periodontal tissue dimensions in the esthetic zone using a non-invasive digital method

Purpose

Direct intraoral scanning and superimposing methods have recently been applied to measure the dimensions of periodontal tissues. The aim of this study was to analyze various correlations between labial gingival thickness and underlying alveolar bone thickness, as well as clinical parameters among 3 tooth types (central incisors, lateral incisors, and canines) using a digital method.

Methods

In 20 periodontally healthy subjects, cone-beam computed tomography images and intraoral scanned files were obtained. Measurements of labial alveolar bone and gingival thickness at the central incisors, lateral incisors, and canines were performed at points 0–5 mm from the alveolar crest on the superimposed images. Clinical parameters including the crown width/crown length ratio, keratinized gingival width, gingival scallop, and transparency of the periodontal probe through the gingival sulcus were examined.

Results

Gingival thickness at the alveolar crest level was positively correlated with the thickness of the alveolar bone plate (P<0.05). The central incisors revealed a strong correlation between labial alveolar bone thickness at 1 and 2 mm, respectively, inferior to the alveolar crest and the thickness of the gingiva at the alveolar crest line (G0), whereas G0 and labial bone thickness at every level were positively correlated in the lateral incisors and canines. No significant correlations were found between clinical parameters and hard or soft tissue thickness.

Conclusions

Gingival thickness at the alveolar crest level revealed a positive correlation with labial alveolar bone thickness, although this correlation at identical depth levels was not significant. Gingival thickness, at or under the alveolar crest level, was not associated with the clinical parameters of the gingival features, such as the crown form, gingival scallop, or keratinized gingival width.

Periodontal phenotype: A review of historical and current classifications evaluating different methods and characteristics

OBJECTIVE

To review the historical and current periodontal phenotype classifications evaluating methods and characteristics. Moreover, to identify and classify the methods based on periodontal phenotype components.

OVERVIEW

Several gingival morphology studies have been frequently associated with different terms used causing confusion among the readers. In 2017, the World Workshop on the Classification of Periodontal and Peri-Implant Diseases and Conditions recommended to adopt the term "periodontal phenotype". This term comprises two terms, gingival phenotype (gingival thickness and keratinized tissue width) and bone morphotype (buccal bone plate thickness). Furthermore, gingival morphology has been categorized on "thin-scalloped", "thick-scalloped" and "thick-flat" considering the periodontal biotype. However, by definition, the term phenotype is preferred over biotype. Periodontal phenotype can be evaluated through clinical or radiographic assessments and may be divided into invasive/non-invasive (for gingival thickness), static/functional (for keratinized tissue width), and bi/tridimensional (for buccal bone plate thickness) methods.

CONCLUSIONS

"Thin-scalloped," "thick-scalloped," and "thick-flat" periodontal biotypes were identified. These three periodontal biotypes have been considered in the World Workshop but the term periodontal phenotype is recommended. Periodontal phenotype is the combination of the gingival phenotype and the bone morphotype. There are specific methods for periodontal phenotype evaluation.

CLINICAL SIGNIFICANCE

The term periodontal phenotype is currently recommended for future investigations about gingival phenotype and bone morphotype. "Thin-scalloped," "thick-scalloped," and "thick-flat" periodontal phenotypes can be evaluated through specific methods for gingival thickness, keratinized tissue width, and buccal bone plate thickness evaluation.

Injectable platelet-rich fibrin and microneedling for gingival augmentation in thin periodontal phenotype: A randomized controlled clinical trial

AIM

The aim of this present study was to evaluate the effect of gingival thickness (GT) and keratinized tissue width (KTW) using injectable platelet-rich fibrin (i-PRF) alone and with microneedling (MN) in individuals with thin periodontal phenotypes.

MATERIALS AND METHODS

In this split-mouth study, 33 systemically healthy patients with thin periodontal phenotypes were randomly treated with MN + i-PRF and i-PRF. I-PRF was injected on one side, and MN + i-PRF was performed on the other side of the same patient at 4 sessions with 10-day intervals. Clinical periodontal measurements, GT and KTW were assessed before the treatment and every month for six months after the final injection.

RESULTS

After the evaluation of GT between the groups, a statistically significant difference was found in MN + i-PRF group at the sixth month. In the intra-group comparisons, a statistically significant increase in GT was observed within both i-PRF [from 0.43 mm ± 0.14 to 0.62 mm ± 0.11 (p < .001)] and MN + i-PRF [from 0.4 mm ± 0.14 to 0.66 mm ± 0.12 (p < .001)] groups at the sixth month.

CONCLUSIONS

In individuals with thin periodontal phenotypes, standalone i-PRF and i-PRF with MN may have an influence in increasing GT. The results suggest that application of i-PRF and MN may be a first step of non-surgical method for increasing gingival thickness.

Prevalence of gingival biotype in adult patients of the dentistry services of two Peruvian hospitals April-June 2018

Introduction: The gingival biotype of a population is important epidemiological data for the best treatment planning, while preserving periodontal health. In Peru there is a shortage of similar data published. Objective: To determine the prevalence of gingival biotype in adult patients of the Dental Service of the Víctor Lazarte Echegaray and Hospital Regional Docente de Trujillo, April - June 2018. Ma-terials and Methods: This cross-sectional, descriptive and observational study included 200 patients from the Dentistry Service of the Víctor Lazarte Echegaray and Hospital Regional Docente de Trujillo. Using the accidental non-probabilistic selection method, the gingival biotype was evaluated through the transparency of periodontal probe technique. To determine the reliability of the method the Kappa statistic was used, finding an inter-evaluator reliability of 0.750 and intra-evaluator of 0.762. Descriptive statistics were used for the results, presenting absolute and percentage frequencies. Results: The prevalence of the thick gingival biotype was 57.5%. Males and females presented predominantly a thick biotype, 63.1% and 54.8% respectively. The groups of 18 to 29 and 30 to 39 years old presented 62.1% and 64.5% a thick biotype, respectively. On the other hand, the majority of people 40 to 50 years old presented a thin gingival biotype (52.8%). Conclusions: The thick gingival biotype was predominant in both sexes and in both hospitals. Also, gingival biotype varies with age, with the thick biotype more prevalent in younger age groups.

Distribuição das características clínicas do fenótipo gengival em pacientes saudáveis

Resumo Introdução A determinação do fenótipo gengival possibilita compreender melhor as variações e diferenças clínicas intra e interindividuais dos tecidos periodontais saudáveis. Objetivo O objetivo deste estudo foi determinar os perfis do fenótipo gengival e compará-los em diferentes regiões da cavidade oral, levando em consideração parâmetros clínicos relacionados aos tecidos moles circunjacentes nos dentes anteriores superiores e inferiores. Material e método Noventa e um pacientes com saúde periodontal foram examinados e os parâmetros clínicos profundidade de sondagem (PS), largura de mucosa ceratinizada (MC), espessura gengival em ambos incisivos centrais superiores (EG) e fenótipo gengival (FG) foram coletados nos dentes anteriores superiores e inferiores. Os dados foram analisados estatisticamente pelos testes t-Student pareado e independente, Correlação de Pearson e Qui-quadrado, com um nível de significância de 5%. Resultado O fenótipo gengival espesso predominou nos dentes anteriores superiores (60,5%), enquanto o fenótipo fino foi mais prevalente nos dentes anteriores inferiores (84,6%). Diferenças estatisticamente significativas foram encontradas para os parâmetros largura de mucosa ceratinizada e espessura gengival em relação aos fenótipos gengivais superiores e inferiores (p<0,05). Não houve diferença estatística entre profundidade de sondagem e o fenótipo gengival nos dentes superiores e inferiores. Conclusão Concluiu-se que o fenótipo gengival espesso é mais frequente nos dentes anteriores superiores e que o fenótipo fino é mais comum nos dentes anteriores inferiores, sendo mais frequente em indivíduos do sexo masculino. Os parâmetros largura de mucosa ceratinizada e espessura gengival mostraram-se adequados à determinação do fenótipo gengival.

Reproducibility of the PIROP ultrasonic biometer for gingival thickness measurements

OBJECTIVES

Gingival thickness (GT) has a great importance in periodontal flap design, gingival recession, and soft tissue esthetic. The aim of this study was to determine the reproducibility of PIROP ultrasonic biometer, which is specially designed for human GT measurements and to compare with the invasive transgingival probing technique.

MATERIALS AND METHODS

GT was measured in 25 periodontally healthy volunteers both by PIROP and an endodontic spreader on the attached gingiva. Reproducibility was assessed by calculating standrad deviaton (SD) in five repeated measurements and Pearson correlation coefficient (r). Agreement between the two methods was evaluated based on Bland-Altman limits of agreement (LoA).

RESULTS

No systemic bias in GT was observed between the two methods. The repeatability of the PIROP was better than the spreader method (SD = 0.14 mm vs 0.20 mm, P < 0.001). With five repetitions, the measurement error of the PIROP was halved. The correlation among the repeated observations were strong (r = 0.86) for the ultrasonic, weak (r = 0.34) for the invasive method. The LoA between the two methods was -0.58 to +0.75 mm.

CONCLUSION

PIROP is a reliable device for GT measurements, but it is recommended to repeat the measurement a few times to improve the precision in individual case.

CLINICAL SIGNIFICANCE

PIROP ultrasonic biometer could be used in routine practice to reliably measure the GT in noninvasive way. After short learning curve the measurement can be done quickly and conveniently.

Assessment of Periodontal Biotype in a Young Chinese Population using Different Measurement Methods

Periodontal biotype is used to describe the morphological characteristics of periodontal tissues and is closely related to periodontal health and prognosis of many dental treatments. This study was undertaken to explore the periodontal biotype distribution in a young Chinese population and to evaluate the accuracy of different methods for gingival thickness (GT) measurement. A total of 372 teeth from 31 periodontally healthy subjects were included. GT was measured simultaneously by probe transparency, transgingival probing and cone-beam computed tomography (CBCT). Some other anatomic parameters, including crown width/crown length ratio, attached gingival width, labial bone thickness and papilla volume were recorded for periodontal biotype classification. As found by probe transparency, the gingivae of 222 teeth (59.68%) were thick, while those of 150 teeth (40.32%) were thin. The mean GT of included subjects was 1.03 ± 0.31 mm as measured by transgingival probing and 1.03 ± 0.24 mm as measured by CBCT. Four groups were identified by cluster analysis. Thick-flap biotype, average-scalloped biotype, average-flap biotype and thin-scalloped biotype comprised 137 teeth (36.83%), 96 teeth (25.81%), 39 teeth (10.48%) and 100 teeth (26.88%), respectively. These results demonstrate that the most common periodontal biotype in this young Chinese population was the thick-flap type with low aesthetic risk.

Gingival biotype revisited-novel classification and assessment tool

OBJECTIVES

To evaluate the relationship between gingival biotypes and gingival thickness based on probe transparency through the gingival margin and to assess the sensitivity of a novel classification method.

MATERIAL AND METHODS

Sixty adult Caucasian subjects were stratified by their gingival biotype (GB) as defined by the transparency of a prototype double-ended periodontal probe through the buccal gingival margin into "thin" (30 subjects), "moderate" (15 subjects), and "thick" (15 subjects) GB. Three additional parameters were also assessed: gingival thickness (GT), probing depth (PD), and gingival width (GW).

RESULTS

Median GT was 0.43 mm (P _25% 0.32; P _75% 0.58) for thin, 0.74 mm (P _25% 0.58; P _75% 0.81) for moderate, and 0.83 mm (P _25% 0.74; P _75% 0.95) for thick GB, respectively. GT was statistically significant different for thin versus moderate and thin versus thick, respectively (Kruskal-Wallis test, p < 0.05; Dunn's test, thin versus moderate: p = 0.002; thin versus thick: p < 0.001; moderate versus thick: p = 0.089). GW was directly correlated with GT (Spearman correlation p < 0.01). The sensitivity of the new classification tool for diagnosing a thin GB was 91.3%. No adverse events or complications were reported.

CONCLUSION

GT differs significantly between the presented GB groups, hence, an alternative classification especially focusing on thin biotypes based on a modified periodontal probe might be advantageous. In addition, the presence of a thick gingiva is associated with a wide band of keratinized tissue.

CLINICAL RELEVANCE

This clinical setting might to be useful to identify high-risk patients with a very thin biotype and, consequently, higher risk for gingival recession after dental treatments.

On the relationship between gingival morphotypes and different crown shape assessments in young Caucasians

OBJECTIVES

The objective of this study was to determine the relationship between crown length as well as crown width and gingival morphotypes (primary aim) and their correlation with tooth shape and papilla height (secondary aim).

MATERIAL AND METHODS

Thirty-six adult subjects were evaluated in this clinical study according to their gingival morphotype (GM) defined by transparency of a periodontal probe through the buccal gingival margin. Eighteen subjects comprised the thin entity group and 18 the control group thick entity, respectively. Besides crown length (CL) and crown width (CW), two different methods to assess crown shape (CW/CL ratio) were compared and analysis of their relation to papilla height was performed.

RESULTS

Nineteen female and 17 male volunteers were enrolled in this study, with a mean age of 24.9 years (±3.4; minimum 18, maximum 35). A statistical significant difference for the crown length could be detected between both groups (p < 0.05) but not for crown width. No significant difference was found for apical or coronal CW/CL ratio besides on tooth 22.

CONCLUSION

Within the limitations of this study and within this young Caucasian study population, only crown length seems to have an association with different gingival morphotypes. Furthermore, papilla height and crown shape do not have a clear correlation on tooth level.

CLINICAL RELEVANCE

Crown shape seems to be not a strong parameter in assessing the gingival morphotype.