Gingival thickness and gingival width in children: a cross-sectional study utilizing ultrasonography

PURPOSE

To measure the gingival phenotype-related features, gingival thickness (GT) and gingival width (GW), in healthy children and to investigate their association between them, with age, gender, tooth-type and arch.

METHODS

The gingival sites of 1029 teeth were included from 64 children (36 males and 28 females), with primary and mixed dentition, attending the paediatric dental clinic of Aristotle University, Thessaloniki. GT and GW were measured ultrasonically and with a periodontal probe, respectively. Mixed effects linear regression models were used to evaluate the association of gingival thickness and gingival width with the under-investigation parameters. Spearman's correlation coefficient was used to evaluate correlation between GT and GW.

RESULTS

Significantly thicker gingiva is found in posterior teeth compared to anterior teeth, in permanent teeth versus primary teeth and in maxillary teeth in comparison to mandibular teeth (p value < 0.001). Regarding GW, significantly wider gingiva is noted in posterior regions (p value = 0.022) and the maxilla (p value < 0.001). Gender-wise and concerning age GT and GW are not significantly affected. A weak and positive correlation between GT and GW is noted (rho 0.30, p < 0.001).

CONCLUSIONS

GT and GW present significant associations with arch and tooth-type. Findings from this study fulfil the further understanding of GT and GW of paediatric patients that are investigated sparsely throughout the literature and demonstrate an accurate, painless and simple method to map the gingiva.

A novel approach for gingiva thickness measurements around lower anterior teeth by means of dental magnetic resonance imaging

OBJECTIVE

This diagnostic accuracy study aims to present the first measurements of gingiva thickness around lower anterior teeth using dental magnetic resonance imaging (MRI) and to compare these measurements with two established methods: (1) gingival phenotype assessment via periodontal probing, and (2) the superimposition of cone-beam computed tomography (CBCT) scans with intraoral scans of teeth and gums.

MATERIALS AND METHODS

Ten patients with substantial orthodontic treatment need and anterior mandibular crowding were consecutively included in this clinical case series. After periodontal probing, each patient underwent a CBCT scan, an intraoral scan of the mandible, and an MRI investigation using a novel mandibula 15-channel dental coil.

RESULTS

The mean gingiva thickness was 0.72 mm measured on MRI and 0.97 mm measured on CBCT, with a mean difference between the measurement methods of 0.17 ± 0.27 mm (p < 0.001). Measurement agreement between the index tests (MRI and CBCT) and the clinical reference standard (probing) yielded an overall percent agreement of 64.94% and 47.02% for MRI and CBCT, respectively. Teeth with thin phenotypes were associated with lower soft tissue dimensions in both free (MRI: 0.56 mm vs. CBCT: 0.79 mm) and supracrestal gingiva (MRI: 0.75 mm vs. CBCT: 1.03 mm) when compared to those with thick phenotypes. However, only the measurements obtained from MRI scans showed statistically significant differences between the two phenotypes.

CONCLUSION

Dental MRI successfully visualizes delicate structures like the gingiva in the anterior mandible and achieves a high correlation with superimposed CBCT scans, with clinically acceptable deviations.

CLINICAL RELEVANCE

The present study helps to establish dental MRI as a radiation-free alternative to conventional radiographic methods.

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.

Gingival phenotype determination: Cutoff values, relationship between gingival and alveolar crest bone thickness at different landmarks

Background/purpose

Gingival phenotype (GP) has been reported to influence the treatment planning and clinical outcomes in several dental specialties. This study aimed to investigate optimal cutoff values for gingival thickness (GT) measurement at different landmarks to determine GP. The correlations between GT and bone thickness (BT) of buccal alveolar crest were also analyzed.

Materials and methods

A total of 600 teeth were included. GP was clinically determined by the transparency of a periodontal probe through the gingival margin (TRAN). Measurements for free gingival thickness (GT1), cementoenamel junction gingival thickness (GT2), supracrestal gingival thickness (GT3), subcrestal 1 mm gingival thickness (GT4) and BT at 1, 3 mm apical from the alveolar crest edge (BT1 and BT2) were assessed on cone-beam computed tomography (CBCT) images. Spearman's correlation coefficient was used to evaluate correlations between GT and BT.

Results

The optimal cutoff values of GT using CBCT method to discriminate GP were 0.75 mm for GT1, 0.85 mm for GT2, 1.15 mm for GT3 and 0.45 mm for GT4. There was significantly positive correlation between GT and BT at all levels (r: 0.375-0.903). The correlations between GT3 and BT (r: 0.789-0.903) were strong, while correlations between GT4 and BT were weak (r: 0.375-0.467).

Conclusion

The optimal cutoff values of gingival thickness using CBCT method to discriminate gingival phenotype at each gingival landmark were determined. The supracrestal gingival thickness might be an indicator of buccal alveolar crest bone thickness, which could provide valuable perspectives on clinical diagnosis, treatment planning and decision-making.

Effect of craniofacial morphology on gingival parameters of mandibular incisors

OBJECTIVES

To investigate the association between the width of keratinized gingiva (WKG), gingival phenotype (GP), and gingival thickness (GT) with craniofacial morphology in sagittal and vertical dimensions.

MATERIALS AND METHODS

WKG, GP, and GT of mandibular anterior teeth in 177 preorthodontic patients (mean age 18.38 ± 5.16 years) were assessed clinically using a periodontal probe, a Colorvue Biotype Probe, and ultrasound by a single examiner. Patients were grouped into skeletal Class I, II, and III and hyperdivergent, normodivergent, and hypodivergent based on ANB and SN-MP angles. Mandibular incisor inclination (L1-NB) was also measured. Clinical and cephalometric measurements were repeated to assess inter- and intraexaminer reproducibility.

RESULTS

A significant association was found between thin GP and skeletal Classes I and III for the left mandibular central incisor (MCI; P = .0183). In skeletal Class III patients, L1-NB angle demonstrated a decreasing trend as phenotype thickness decreased. A significant association was found between thin phenotype and normodivergent and hypodivergent groups for MCIs (left: P = .0009, right: P = .00253). No significant association between WKG or GT and craniofacial morphology was found.

CONCLUSIONS

Thin GP is associated with skeletal Class I and III for the left MCI. Thin GP is associated with hypodivergent and normodivergent skeletal patterns for the MCIs. There was no association between WKG and GT and craniofacial morphology in both skeletal and vertical dimensions. Dental compensations that exist due to different craniofacial morphology may influence the GP.

Clinical and computed tomographic evaluations of periodontal phenotypes in a Chinese population: a cross-sectional study

OBJECTIVES

To investigate the diagnostic value of probe transparency related to gingival thickness (GT) and keratinized gingival width (KGW) at individual and site levels and explore the relationship of buccal bone plate thickness (BT) with GT and KGW.

MATERIALS AND METHODS

A total of 1,606 teeth from 167 patients with periodontally healthy maxillary anterior region were included. GT was measured with probe transparency and transgingival probing. KGW was measured directly. BTs were assessed at the level 1 mm apical to the alveolar crest (BT1) and midpoint of the root (BT2) and evaluated at individual and tooth levels along with their mutual associations.

RESULTS

The prevalence of thick gingiva was 53% with probe transparency measurement and 51% with transgingival probing. The cutoff gingival thickness was 0.8 mm, which correlated moderately with a Cohen's kappa of 0.386. The mean GT, KGW, and BTs (BT1 and BT2) in the maxillary anterior region were 0.97 ± 0.46, 5.51 ± 1.62, 0.85 ± 0.31, and 0.79 ± 0.32 mm, respectively. GT and KGW correlated mildly (r = 0.261), and GT and BTs correlated moderately (BT1: r = 0.298; BT2: r = 0.338). GT and BTs differed significantly between men and women and among different tooth sites.

CONCLUSIONS

GT and BTs correlated positively in the maxillary anterior region and varied within and among individuals. Sex was a factor influencing the gingival phenotype and bone morphotype.

CLINICAL RELEVANCE

GT measured with transgingival probing, with a cutoff of 0.8 mm, could serve as an objective measure to distinguish different gingival phenotypes.

Modified coronally advanced tunnel versus epithelialized free gingival graft technique in gingival phenotype modification: a comparative randomized controlled clinical trial

OBJECTIVES

The gingival thickness (GT) and keratinized tissue (KT) height are defined as the gingival phenotype. Both the modified coronally advanced tunnel technique (MCAT) and free gingival grafts (FGG) are used in modifying the gingival phenotype. This study aims to compare MCAT and FGG in gingival phenotype modification.

MATERIALS AND METHODS

One hundred and forty recessions in 50 patients with thin and insufficient keratinized tissue at the anterior mandible were treated with either MCAT or FGG. GT, KT height, recession depth, recession width, probing depth, and clinical attachment level were evaluated at baseline and 6 weeks, 6 months, and 12 months. GT change, KT change, root coverage (RC), clinical attachment gain, and complete root coverage (CRC) were calculated. The wound healing index, tissue appearance, patient expectations, aesthetic, and dentin hypersensitivity were assessed at baseline and 6 months.

RESULTS

All periodontal variables showed significant change from baseline to 12 months in both groups (p < 0.05). While FGG resulted in more KT change (p < 0.001), all MCAT sites showed at least 2 mm KT change in 12 months. MCAT resulted in greater GT change (p < 0.05) and RC (p < 0.003). In contrast, there was no significant inter-group CRC difference (p = 0.523). All patient-based variables were favorable to MCAT (p < 0.05), except dentin hypersensitivity (p = 0.225).

CONCLUSIONS

Both techniques were successful in terms of gingival phenotype modification in the anterior mandible. Additional GT increase, RC, and patient-based outcomes favored MCAT, though KT change proved greater with FGG.

CLINICAL RELEVANCE

Clinicians may choose MCAT for higher GT increase whereas FGG for more KTC.

TRIAL REGISTRATION NUMBER

NCT04690140 and date: 12/26/2020.

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.

Gingival phenotype and its relationship with different clinical parameters: a study in a Dominican adult sample

OBJECTIVES

The purpose of this study was to estimate the prevalence of thin and thick gingival phenotype (GPh) in a sample of Dominican subjects and correlate it with clinical parameters.

MATERIALS AND METHODS

One-hundred seven periodontal healthy volunteers in the range of 18-73 years were enrolled in the study. GPh was defined by the transparency of a periodontal probe through the buccal gingival margin on the upper right or left central incisor. Clinical periodontal parameters such as keratinized gingiva width (WKG), attached gingiva width (WAG), probing depth (PD), plaque index (PI), and gingival index (GI) were recorded by a calibrated examiner. Frequency distribution of qualitative variables was calculated. For quantitative variables, Mann-Whitney and Kruskal-Wallis tests were used for comparison of groups.

RESULTS

There was no association between GPh and sex. There were no significant differences between thin and thick GPh regarding age, PD, GI, and interproximal index. The association between tooth morphology and GPh was significant (p = 0.018). Median amount of keratinized gingiva was significantly larger (p = 0.01) in subjects with thin gingival phenotype (median = 6.00 mm) when compared with subjects with thick gingival phenotype (median = 5 mm).

CONCLUSIONS

Subjects with thin GPh presented larger WKG. Furthermore, there was an association between tooth morphology and GPh.

CLINICAL RELEVANCE

This is the first study to report the distribution of gingival phenotype and its relationship with different periodontal parameters of a Caribbean population. Our findings can contribute to the clinicians when planning or performing dental procedures.

The influence of gingival phenotype on the morphology of the maxillary central papilla

BACKGROUND

Preservation of the interdental papilla is an essential part of the functional and esthetic rehabilitation of dental treatment. It has been described that thicker gingival tissues are more resistant to recession. The main objective of this investigation was to analyze whether a thin gingival phenotype represents a potential risk indicator affecting interdental papilla fill, height, or width in an esthetic region between maxillary central incisors. The secondary goals were: (1) to analyze parameters describing the papilla-fill, height, width, and effect of papilla base width on the vertical papillary dimension; (2) to determine correlation between different non-invasive measurements of gingival thickness; (3) to compare both sexes.

METHODS

A total of 54 periodontally healthy students (20-30 years old) were included in the study. Gingival thickness was measured using Pirop Ultrasonic Biometer. Gingival phenotype was also assessed by gingival probe transparency. Papilla height and width were measured, and the degree of papilla recession was classified.

RESULTS

No significant relationship between papilla fill, height, width and gingival probe transparency or gingival thickness was found. Gingival thickness and gingival probe transparency showed a significant relationship (P < 0.001). There was a significant relationship between papilla height and papilla fill (P = 0.028). A papilla which filled the interdental space completely seemed to be shorter. A strong positive correlation between papilla height and papilla width was found (P < 0.0001). The papilla between maxillary central incisors was significantly higher in males (P = 0.01).

CONCLUSION

The appearance of the interdental papilla may be influenced by various factors. Within the limitations of this study, the results showed that the thin gingival phenotype alone is no potential risk indicator affecting interdental papilla fill, height, or width. It seems that there may be some effect of papilla base width on its vertical dimension. Gingival probe transparency is a simple reliable method of assessment of gingival thickness with a threshold value of 1-mm gingival thickness between the thick and thin phenotypes.

[Research progress of the influence of gingival biotype on the prognosis of oral treatment]

The gingival biotypes, which were proposed by Ochsenbein, could be divided into thin gingival biotype and thick gingival biotype. There are several methods to judge the gingival biotypes, such as visual methods, periodontal probe transparency and cone-beam CT. Each method has its own characteristics. The gingival biotype is affected by a variety of factors, such as age, gender, crown shape, interdental papillary height, alveolar bone thickness and alveolar bone morphology. In the anterior region, different gingival biotype has different effects on oral aesthetics, and different gingival biotype also has different effects on the prognosis of periodontal, orthodontic and implant treatment. This article mainly reviews the influence of gingival biotype on the prognosis of oral treatment.

Relationship between periodontal status of mandibular incisors and selected cephalometric parameters : Preliminary results

Purpose

The aim of this cross-sectional study was to evaluate the correlation between the periodontal tissue of mandibular incisors and several dentoalveolar and skeletal cephalometric parameters.

Materials and methods

The sample consisted of 35 patients (mean age 26.42 ± 8.02 years). Eligibility criteria included good overall health status with no history of dental trauma, congenital defects, active periodontal diseases, restorative and prosthetic treatment in the area of the mandibular incisors. Gingival recession width and height (GRW, GRH), gingival thickness (GT), width of keratinized gingiva (WKT) and clinical attachment loss (CAL) were evaluated at 140 lower incisors. Incisors inclination (1-:ML), skeletal class (ANB, WITS), intermaxillary angle (NL:ML) and mandibular symphysis dimensions (symph. length and width) were assessed in cephalograms. Spearman’s correlation coefficient was used for statistical analysis at the P < 0.05 level.

Results

A statistically significant positive moderate correlation was found for GT and WITS and also symph. length. WKT correlated positively with ANB, WITS and symph. length, with moderate strength of the correlation. GRW, GRH and CAL did not correlate with any cephalometric parameters.

Conclusion

The results of this study indicated evidence for an association between WKT and GT and some cephalometric variables—ANB, WITS, and symphysis length.