Influence of lip retraction on the cone beam computed tomography assessment of bone and gingival tissues of the anterior maxilla

Assessment of the correlation between supracrestal gingival tissue dimensions and other periodontal phenotypes components via the digital registration method: a cross‑sectional study in a Chinese population

BACKGROUND

Supracrestal gingival tissue dimensions (SGTDs) has been considered to be an essential element of periodontal phenotype (PP) components. This study aimed to explore the relationship between SGTDs and other PP components by digital superposition method that integrated cone beam computed tomography (CBCT) with intraoral scanning.

METHODS

This cross-sectional study was conducted at the Stomatology Hospital of Fujian Medical University. Participants were recruited based on the inclusion and exclusion criteria. The data obtained from the digital scanner (TRIOS 3, 3Shape, Denmark) and CBCT images were imported into the TRIOS software (Implant Studio, 3Shape, Denmark) for computing relevant parameters. The significant level was set at 0.05.

RESULTS

A total of 83 participants with 498 maxillary anterior teeth were finally included. The mean values of supracrestal gingival height (SGH) and the distance from the cementoenamel junction (CEJ) to the crest of the alveolar ridge (CEJ-ABC) on the buccal site were significantly higher than palatal SGH (SGH-p) and palatal CEJ-ABC (CEJ-ABC-p). Men exhibited taller CEJ-ABC and SGH-p than women. Additionally, tooth type was significantly associated with the SGH, SGH-p and CEJ-ABC-p. Taller SGH was associated with wider crown, smaller papilla height (PH), flatter gingival margin, thicker bone thickness (BT) and gingival thickness (GT) at CEJ, the alveolar bone crest (ABC), and 2 mm apical to the ABC. Smaller SGH-p displayed thicker BT and GT at CEJ, the ABC, and 2 and 4 mm apical to the ABC. Higher CEJ-ABC showed lower interproximal bone height, smaller PH, flatter gingival margin, thinner GT and BT at CEJ, and 2 mm apical to the ABC. Smaller CEJ-ABC-p displayed thicker BT at CEJ and 2 and 4 mm apical to the ABC. On the buccal, thicker GT was correlated with thicker BT at 2 and 4 mm below the ABC.

CONCLUSION

SGTDs exhibited a correlation with other PP components, especially crown shape, gingival margin and interdental PH. The relationship between SGTDs and gingival and bone phenotypes depended on the apico-coronal level evaluated.

TRIAL REGISTRATION

This study was approved by the Biomedical Research Ethics Committee of Stomatology Hospital of Fujian Medical University (approval no. 2023-24).

Determining the periodontal phenotype-Probe transparency versus actual: A diagnostic study

AIMS

Assessment of the validity of the transparency of the periodontal probe as a tool for determining the periodontal phenotype.

MATERIALS AND METHODS

The periodontal phenotype was assessed at the six upper anterior teeth of 75 subjects using two methods. One is through assessing the transparency of the periodontal probe upon insertion into the gingival sulcus. The second method was through the assessment and clustering of the width of keratinized gingiva clinically and the gingival and buccal plate thickness on Cone Beam Computed Tomography scan.

RESULTS

The probe transparency approach correctly identified thick periodontal phenotype in most cases (41 out of 43 [95%]). However, this was not the case for thin periodontal phenotype; probe transparency approach identified 64% of the thin sites (261 out of 407) and misclassified nearly one third of the patients.

CONCLUSION

The probe transparency approach is a valid approach in identifying the phenotype in subjects with thick phenotype but not in subjects with thin phenotype.

CLINICAL SIGNIFICANCE

The definition of periodontal phenotype has recently changed. Accurate designation has been shown to affect treatment outcomes especially esthetic ones in different disciplines of dentistry. Probe transparency is commonly used by clinicians and researchers. Assessment of the validity of this method based on the most recent definition and compared to actual assessment of bone and gingival thickness is of great clinical value.

Comparative Evaluation of the Accuracy of Gingival Thickness Measurement by Clinical Evaluation and Intraoral Ultrasonography

This study aimed to investigate the accuracy of gingival thickness measurement by two methods of clinical evaluation and intraoral ultrasonography. The gingival thickness was measured in the midbuccal area of the right maxillary lateral incisor and first molar teeth in 30 individuals. For clinical measurement, a #15 K-file with rubber stops was vertically inserted 2 mm apical to the gingival margin and the length of the file in the tissue was measured using a digital caliper. Ultrasonographic measurement was performed using an intraoral probe on the gingival surface in the midbuccal area, at the entry point of the file. Statistical analysis was performed by paired t-test, correlation coefficient, and receiver operating characteristic (ROC) curve (α = 0.05). In the anterior region, the mean gingival thicknesses using ultrasonography (1.517 ± 0.293 mm) and clinical evaluation (1.610 ± 0.272 mm) were not significantly different (p = 0.434). In the posterior region, the mean gingival thicknesses were significantly different between ultrasonography (1.372 ± 0.442 mm) and clinical evaluation (1.626 ± 0.310 mm) (p = 0.006). The area under ROC curve values for ultrasonographic measurements in the anterior and posterior regions were 0.681 and 0.597, respectively. The use of ultrasonography with an intraoral probe has acceptable accuracy for the determination of gingival thickness, especially for the anterior regions.

Accuracy of cone-beam computed tomography in determining gingival thickness: a systematic review and meta-analysis

OBJECTIVE

To assess the accuracy of cone-beam computed tomography (CBCT) for determining gingival thickness.

MATERIAL AND METHODS

Searches were undertaken in PubMed/MEDLINE, EMBASE, LILACS, Web of Science, Scopus, LIVIVO, and gray literature (Google Scholar and ProQuest) for studies considered eligible according to the following criteria: cross-sectional observational studies, which compared CBCT accuracy with that of transgingival probing when determining gingival thickness, in adult patients with good periodontal health. No language or time restrictions were applied in this systematic review. The risk of bias was assessed using the Joanna Briggs Institute (JBI) Critical Appraisal Checklist for analytical cross-sectional studies.

RESULTS

Six articles were included for qualitative synthesis, involving a pooled sample of 132 patients with a mean age of 29 years (18-51 years). Of these 6 studies, 5 were eligible for quantitative analysis. The meta-analysis showed no statistically significant difference between CBCT and transgingival probing measures of gingival tissue (mean difference of 0.10 (95% CI-0.17-0.38). No significant level of heterogeneity was detected (Tau²-P = 0.0662; I² = 0%; H²-P = 1.000; Q-P = 1.134). According to the GRADE criterion, confidence in the cumulative evidence was considered low.

CONCLUSIONS

CBCT is an accurate method for determining gingival tissue thickness, comparable to the reference standard (transgingival probing).

CLINICAL RELEVANCE

CBCT could be considered for gingival thickness measurement when bone thickness is also needed, and thereby aid in the assessment of gingival biotype without the discomfort and anesthesia needed in transgingival probing.

TRIAL REGISTRATION

This protocol was registered at the PROSPERO database (International Prospective Register of Systematic Review) under registration number CRD42022326970. Available from: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022326970 .

Gingival landmarks and cutting points for gingival phenotype determination: A clinical and tomographic cross-sectional study

BACKGROUND

This cross-sectional study assessed the role of gingival landmarks (GLs) and cutting points (CPs) for gingival phenotype (GP) determination.

METHODS

Six maxillary anterior teeth (70 subjects) were evaluated using soft tissue cone-beam computed tomography (ST-CBCT). Gingival thickness was measured at different GLs: 1) tissue zone (gingival margin [GM], 1 and 2 mm apical to GM, cemento-enamel junction, above the bone crest); 2) bone zone (buccal bone crest [BBC], 1, 2, and 3 mm apical to BBC). CPs of 0.6, 0.8, 1.0, 1.2, and 1.5 mm were used to discriminate between thin and thick GP. The clinical determination of GP was made based on transparency of the periodontal probe (TRAN).

RESULTS

The prevalence of thin and thick GP depended on the GL and CP. Considering the CP (1 mm), thin GP at the tissue zone ranged from 99% at the GM to 10.2% above the bone crest. In the bone zone, thick GP ranged from 28% at the BBC to 6% at 3 mm apical to the BBC. The predictability of a correct assessment of GP by TRAN compared with ST-CBCT was influenced by the GLs and CPs. A slight agreement (kappa <0.2) and low accuracy (area under the curve <0.7) were found between methods.

CONCLUSIONS

The determination of thin and thick GPs is related to the gingival landmarks and CPs. Further studies are required for a well-defined treatment protocol considering different gingival landmarks in tissue and bone zones. An ST-CBCT may be useful for this purpose.

Assessment of the relationship between tooth inclination and gingival and alveolar bone dimensions using computed tomography of the maxillary anterior teeth: a cross-sectional study

OBJECTIVE

The present study aimed to investigate the relationship between tooth inclination and gingival and bone dimensions in maxillary anterior teeth.

METHODS

This cross-sectional study included cone-beam computed tomography (CBCT) images of 160 maxillary anterior teeth (30 individuals). Tooth inclination, gingival and bone thickness, and distances from cementoenamel junction to alveolar bone crest and gingival margin were measured in the labial surface. The correlations were analyzed using Pearson and partial correlation tests (p≤0.05).

RESULTS

In the central incisors, tooth inclination was positively and significantly related to apical bone thickness (R = 0.34, p= 0.001). In the canines, tooth inclination was negatively and significantly related to cervical bone thickness (R = - 0.34, p= 0.01) and positively associated to apical bone thickness (R = 0.36, p= 0.01) and to gingival margin-cementoenamel junction distance (R = 0.31, p= 0.03). In the lateral incisors, tooth inclination was not associated with gingival or bone dimensions.

CONCLUSIONS

In the central incisors, the greater the labial tooth inclination, the greater is the apical bone thickness. In the canines, the greater the labial tooth inclination, the smallest is the cervical bone thickness, the greater is the apical bone thickness, and the greater is the gingival margin. Gingival and bone dimensions should be assessed when planning orthodontic treatment involving buccal movement of central incisors and canines.

Relationship between smile type and periodontal phenotype: a clinical and tomographic cross-sectional study

OBJECTIVES

To evaluate the correlation between smile type (ST) and the periodontal phenotype (PP).

MATERIAL AND METHODS

Clinical and photographic examinations of 164 participants (48 men and 116 women, mean age 22.9 ± 4.6 years) were performed, including an evaluation of ST (high, average, and low), gingival phenotype (GP) by transparency of the periodontal probe (TRAN), keratinized tissue width (KTW), gingival architecture (GA), tooth shape (TS), and papilla height (PH). A subgroup of 70 participants underwent soft-tissue cone-beam tomographic examinations (ST-CBCT), in which GP, gingival thickness (GT), buccal bone thickness (BBT), and the distances from the gingival margin and cementoenamel junction to the buccal bone crest (GM-BBC and CEJ-BBC) were evaluated. The data were analyzed using one-way ANOVA, Student's t-test, and chi-square tests, with the level of significance set at 0.05.

RESULTS

High, average, and low STs were found in 31.7%, 56.7%, and 11.6% of the participants, respectively. Sex (p=0.001), GP evaluated using TRAN (p=0.021) and ST-CBCT scans (p=0.009), GA (p<0.001), and TS (p=0.001), were associated with STs. The prevalence of thin GP was: 63% in low, 50% in average, and 38% in high smile types. KTW (p=0.004), PH (p<0.001), GT at different landmarks (p<0.05), CEJ-BBC (p=0.017), and GM-BBC (p=0.001) were significantly different among STs. The highest GT and KTW were found in the high-smile group, average-smile presented the higher CEJ-BBC while GM-BBC and PH, were higher in low-smile group.

CONCLUSION

Periodontal phenotype components presented important difference over the smile types.

CLINICAL RELEVANCE

A detailed examination of smile types is an essential part of treatment planning, especially when the patient has high esthetic demands. Clinical and tomographic individual analysis of periodontal phenotypes over the smile types may be helpful for a case-by-case approach, and for the development of well-defined treatment protocols.

Methods to assess tooth gingival thickness and diagnose gingival phenotypes: A systematic review

OBJECTIVE

Measurement of the periodontal soft tissue dimension is crucial for clinical decision-making and aesthetic prognosis. However, the effectiveness of different measuring methods remains unclear. This systematic review aimed to explore the diagnostic accuracy of two non-invasive methods (namely CBCT and ultrasound) for gingival thickness measurement at different tooth positions.

MATERIALS AND METHODS

A systematic search was performed using PubMed (including Medline), PubMed Central, OVID, Cochrane Library, LILACS and OpenGrey. Studies focusing on comparisons between CBCT, ultrasound and direct transgingival probing were included. The means, SDs and correlation coefficients with 95% confidence intervals were extracted and analyzed using Review Manager and R software.

RESULTS

Twelve studies were selected. No significant difference was found between CBCT measurement and transgingival probing in the anterior and posterior dentition, and a moderate correlation was observed between these two methods (r = 0.41). A weak correlation was found between ultrasound measurement and transgingival probing (r = 0.32), and a slight but statistically significant difference was found when comparing ultrasonic devices and transgingival probing in the posterior area.

CONCLUSION

CBCT can be considered a relatively reliable method for gingival thickness measurement in both the anterior and posterior areas compared with direct probing. Ultrasonic devices provide limited accuracy in the posterior area but are relatively comparable with direct clinical assessments in the anterior area.

CLINICAL SIGNIFICANCE

Measurement location may affect the diagnostic accuracy and repeatability of gingival thickness measurements. Appropriate method selection in different clinical scenarios is crucial to aesthetic outcome prediction and decision-making.

Three-dimensional (3D) facially driven workflow for anterior ridge defect evaluation: a treatment concept

The esthetic rehabilitation of anterior ridge defects and the achievement of patient satisfaction has become major clinical challenges for dentists and technicians. Poor diagnosis and treatment planning are frequently associated with multiple surgical procedures which fail to meet patient expectations. The loss of hard and soft tissues in esthetic compromised zone is commonly associated with anterior ridges and affects the rehabilitation prognosis. The presence of interdental papilla and papillary configuration play a decisive role in patient satisfaction. A treatment planning considering esthetic parameters, prosthetic needs, and morphological defects must be conducted to improve treatment outcomes. Therefore, this study aims to propose a treatment concept for anterior ridge defects focusing on digital evaluation systems and guided by an ideal facially driven smile design project. In addition, the relevance of the papilla for the esthetic outcomes and the treatment alternatives for anterior ridge defects are also addressed.

Accuracy of high-resolution ultrasound (US) for gingival soft tissue thickness mesurement in edentulous patients prior to implant placement

OBJECTIVES

To evaluate and compare the accuracy of high-resolution ultrasound (US) with two different cone beam CT (CBCT) units and clinical assessment for measuring gingival soft tissue thickness in edentulous patients prior to implant placement.

METHODS AND MATERIALS

The study consisted of 40 maxillary implant sites of 40 healthy patients (20 females, 20 males; mean age, 47.88 years). We prospectively evaluated labial/buccal gingival thickness in 40 implant regions (16 anterior and 24 posterior) by using limited field of view (FOV) CBCT images and US images in comparison to gold standard transgingival probing measurements. One-way analysis of variance (ANOVA) was used to compare mean measurements obtained from CBCT (Morita and Planmeca), US, and transgingival probing. Interclass correlation coefficient (ICC) estimates were calculated based on means with two-way mixed and absolute-agreement model. Bland Altman plot was used to describe agreement between clinical vs US and CBCT measurements by constructing limits of agreement. Statistical significance was set at p < 0.05.

RESULTS

There was no significant difference between methods used according to mean gingival thickness measurements obtained from the top (p = 0.519) and bottom (p = 0.346) of the alveolar process. US and CBCT measurements highly correlated with clinical measurements for both top and bottom alveolar process gingival thickness (p < 0.001). Distribution of differences between clinical measurements and both CBCT measurements showed statistically significant differences according to 0 (p < 0.05). Distribution of differences between clinical measurements and US measurements did not show statistically significant difference (p > 0.05).

CONCLUSION

High-resolution US provided accurate information for the measurement of gingival soft tissue thickness in edentulous patients prior to implant placement.

Coronally advanced flap combined with sticky bone and i-PRF-coated collagen membrane to treat single maxillary gingival recessions: Case series

INTRODUCTION

Numerous techniques have been reported in the literature for the reconstruction of gingival recession defects. The purpose of this case series was to evaluate clinically and radiographically the efficacy of sticky bone with i-PRF-coated collagen membrane in the treatment of gingival recession.

CASE PRESENTATION

Sixteen patients exhibiting isolated Miller's Class I or II recession in the maxillary esthetic zone were treated using sticky bone (i-PRF + freeze-dried bone allograft) with i-PRF-coated collagen membrane using the coronally advanced flap. Clinical parameters including probing depth (PD), width of keratinized gingiva (WKG), gingival thickness (GT), and recession depth (RD) were recorded at baseline and 6 months post-surgery. The radiographic (ST-CBCT) measurements computed were labial plate thickness (OT1, OT3, and OT5) and GT (GT1, GT3, and GT5) at baseline and 6 months post-treatment. Twelve out of sixteen treated cases achieved complete root coverage. An increase in GT was observed in all the cases.

CONCLUSIONS

Within the limitations of this case series, sticky bone with i-PRF-coated collagen membrane showed promising results in the treatment of isolated maxillary Miller's Class I or II gingival recession and serves as an altered approach for root coverage procedure. However, histological analysis and larger sample size are needed to establish definitive proof of soft and hard tissue regeneration.

Clinical and tomography evaluation of periodontal phenotypes of Brazilian dental students

BACKGROUND

The periodontal phenotype (PP) plays an important role in the function, esthetics, and maintenance of periodontal health and has a great influence in periodontal, restorative, and dental implant therapies.

AIM

The aim of this study was to conduct a clinical evaluation of the PP and its morphometric variations through the cone-beam computed tomography (CBCT), from dentistry students with periodontal health.

MATERIALS AND METHODS

Sixty students were examined, and the clinical parameters of probing depth and width of keratinized tissue (WKT) in the upper anterior segment were accessed. The gingival thickness was evaluated as thick or thin, through the translucency of the periodontal probe through the marginal gingiva. By convenience sample, 13 students were selected to assess bone thickness and gingival thickness and biological width through the previous CBCT examination.

RESULTS

The most prevalent PP, according to the classification by De Rouck et al., was the thick scalloped (55%), and using the classification of Kao and Pasquinelli, the thick PP was most common (73,3%). The thick PP in both the classifications was more prevalent in both genders and the WKT was significantly higher in the thick-flat scalloped PP. The bone thickness was always greater than the gingival thickness in CBCT examinations both in the measures 1 mm and 3 mm above the bone crest. The average of the biological width measurement was 2.02 mm.

CONCLUSIONS

The thick PP was most prevalent in the sample studied, and the gingival thickness was always thinner than the bone thickness in the measures evaluated.

A novel soft tissue cone-beam computed tomography study in the evaluation of gingival thickness associated with subepithelial connective tissue graft versus acellular dermal matrix in the management of gingival recession: A clinical study

BACKGROUND

Dental esthetic awareness among patients led the clinicians to introduce newer materials and predictable techniques that satisfy the patients' esthetic demands.

AIM

To evaluate and compare the efficacy of subepithelial connective tissue graft (SECTG) and acellular dermal matrix (ACDM) allograft in the treatment of Millers Class I or Class II recession with the determination of gingival thickness using an impertinent method, soft tissue cone-beam computed tomography (ST-CBCT).

MATERIALS AND METHODS

A split-mouth study with a total of ten patients with bilateral Millers class I or class II recession is randomly assigned by a coin toss method as Group I (SECTG) and Group II (ACDM) along with coronally advanced flap. Clinical parameters including recession height (RH), recession width (RW), probing depth, clinical attachment level (CAL), and height of keratinized tissue (HKT) were evaluated at baseline, 90th day, and 180th day for both groups. The thickness of keratinized tissue (TKT) was determined by most reliable, predictable and noninvasive method called ST-CBCT.

RESULTS

Statistically significant reduction in RH and RW, gain in CAL, and increase in HKT and TKT in both Group I and Group II were seen in 90th day and 180th day. However, when both Group I and Group II were compared between 0 and 180th day, the change in RH and RW, gain in CAL, and increase in HKT and TKT did not show any statistically significant change.

CONCLUSION

The present study suggested that root coverage with both SECTG and ACDM is very predictable procedure and it is stable for 6 months. ST-CBCT is a newer dimension in periodontal imaging and will certainly aid clinicians in the execution of various treatment modalities with increased predictability.

Determination of intra-oral surface areas by cone-beam computed tomography analysis and their relation with anthrometric measurements of the head

Purpose

Determination of intra-oral surface areas might contribute to our understanding of the physiology of the oral cavity and oral diseases. In previous studies, the intra-oral surface area was determined using a laborious and technically challenging method. Our aim was to develop an easy and non-invasive method to determine the intra-oral surface areas.

Methods

In this study, we used cone-beam computed tomography (CBCT) and digital analysis in 20 human cadavers to determine various intra-oral surface areas, based on digital segmentation. Next, we explored whether there was a relationship between various intra-oral surface areas and anthropometric measurements of the head using Pearson correlation coefficient.

Results

Using CBCT and digital analysis, it was possible to determine various intra-oral surface areas. On average, the total intra-oral surface area was 173 ± 19 cm². Moderate, statistical significant correlations were observed between (1) the length of the head and the palatal surface area, as well as (2) the depth of the head and the surface area of the tongue. These correlations suggest the feasibility of estimating intra-oral surface areas without relying on CBCT imaging.

Conclusions

This study presents a technique for measuring the intra-oral surface areas by CBCT imaging in combination with digital analysis. The results of this study suggest that anthropometric measurements of the head might be used to estimate the surface areas of the palate and tongue.

Uso de métodos não invasivos para avaliação da espessura muco-gengival: a tecnologia a favor do diagnóstico

O objetivo no presente estudo foi realizar uma revisão atualizada da literatura sobre os diferentes métodos não invasivos utilizados para avaliação da espessura muco-gengival. O biotipo gengival é considerado um dos principais elementos de influência no resultado do tratamento estético. Pacientes com gengiva espessa demonstram ser mais resistentes à recessão gengival após terapia cirúrgica e/ou restauradora. Em contrapartida, pacientes com biotipo fino apresentam maior risco de recessão, sendo necessário, muitas vezes, o enxerto de tecido conjuntivo. O palato é a principal área doadora para enxerto de tecido conjuntivo subepitelial, sendo que a determinação da espessura da mucosa palatina é de grande importância para a previsibilidade dos procedimentos cirúrgicos. Existem diversos métodos para mensurar a espessura muco-gengival, alguns considerados invasivos, como: a avaliação transgengival (ou transmucosa); e outros, mais recentes, considerados não invasivos, como as imagens seccionais de ultrassom, tomografias computadorizadas ou imagens de ressonância magnética. Apesar de diversos estudos demonstrarem resultados positivos do uso de exames por imagens para avaliação da espessura dos tecidos muco-gengivais, concluiu-se que os métodos invasivos ainda parecem ser os mais utilizados.

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.