The use of digital technologies in peri-implant soft tissue augmentation - A narrative review on planning, measurements, monitoring and aesthetics.

OBJECTIVE: To identify the different uses and modalities of digital technologies to diagnose, plan and monitor peri-implant soft tissue conditions and aesthetics. METHODS: A comprehensive narrative review of pertinent literature was conducted, critically appraising key digital technologies that may assist peri-implant soft tissue augmentation and assessment. An electronic search on four databases including studies published prior to 1st July 2023 was performed and supplemented by a manual search. RESULTS: Predominantly, tools such as cone beam computed tomography (CBCT), intraoral scanning (iOS), intraoral ultrasonography and digital spectrophotometry were commonly to assess and monitor peri-implant soft tissues. The main clinical and research applications included: (i) initial assessment of mucosal thickness, supra-crestal tissue height and keratinized mucosa width, (ii) evaluation of peri-implant soft tissue health and inflammation, (iii) monitoring profilometric changes and midfacial mucosal margin stability over time and (iv) aesthetic evaluation through colour assessment. While evidence for some digital tools may be limited, the integration of digital technologies into peri-implant soft tissue management holds great promise. These technologies offer improved precision, comfort and speed in assessment, benefiting both patients and clinicians. CONCLUSION: As digital technologies progress, their full potential in peri-implant soft tissue augmentation and their value will become more evident with ongoing research. Embracing these innovations and their potential benefits is recommended to ensure that during progress in implant dentistry, patient care is not hindered.

Ultrasonography-Derived Elasticity Estimation of Live Porcine Oral Mucosa.

OBJECTIVES: To investigate the biomechanical properties of porcine oral tissues with in vivo ultrasonography and to compare the difference between oral alveolar mucosa and gingival tissue concerning compressional and tensile mechanical strain. MATERIALS AND METHODS: Sinclair minipigs (6 females and 4 males, 6 to 18 months of age) were anesthetized for ultrasonography. In vivo high-frequency tissue harmonic ultrasound (12/24 MHz) cine-loops were obtained while inducing mechanical tissue stress (0 to 1 N). Post-processing strain analysis was performed in a cardiac speckle tracking software (EchoInsight®). Region of interest (ROI) was placed for gingival and alveolar mucosa tissues for longitudinal (compressional) and tensile strain analyses. A calibrated gel pad was employed to determine the absolute force (pressure) for the measured tissue strain response function. The resulting elasticity data was statistically analyzed using custom Matlab scripts. RESULTS: In total, 38 sonography cine-loops around the third premolars were included in the investigation. The longitudinal strain of alveolar mucosa ε AM L was found to be significantly (P < .05) larger than that of gingiva ε G L . Across the measured force range, ε AM L ~ 1.7 × Îµ G L . Significant differences between alveolar mucosa and gingiva tissues were found for all forces. The tensile strain of the alveolar mucosa ε AM T was found to be ~2 × Îµ G T (on the epithelial surface of the gingiva). Both were statistically significantly different for forces exceeding ~0.08 N. At depth, that is, 500 and 1000 µm below the epithelial surface, the gingiva was found to have less ability to stretch contrary to the alveolar mucosa. Gingival tissue at 500 µm depth has significantly less tensile strain than at its surface and more than at 1000 µm depth. In contrast, the tensile strain of alveolar mucosa is largely independent of depth. CONCLUSION: Ultrasonography can reveal significant differences in oral alveolar mucosal and gingival elastic properties, such as compressional and tensile strain. Under minute forces equivalent to 10 to 40 g, these differences can be observed. As dental ultrasound is a chairside, and noninvasive modality, obtaining real-time images might soon find clinical utility as a new diagnostic tool for the objective and quantitative assessment of periodontal and peri-implant soft tissues in clinical and research realms. As ultrasound is a safe modality with no known bioeffects, longitudinal monitoring of areas of concern would be particularly attractive.

Clinical and radiographic assessment of gummy smile patients with altered passive eruption: a cross-sectional study in a Thai population.

OBJECTIVES: The study aimed to evaluate the clinical crown length (CCL) among patients diagnosed with altered passive eruption (APE), the causes of a gummy smile, the prevalence of APE, and the correlation between parameters. MATERIALS AND METHODS: A total of 86 gummy smile patients (516 teeth) underwent clinical examination and assessment using cone-beam computed tomography (CBCT), photography, and intraoral scanning. RESULTS: Significantly shorter CCL and distance between the cementoenamel junction and bone crest (CEJ-BC) were observed among APE-affected teeth (p < 0.05). Among the patients, 56.1% of patients were diagnosed with APE, and most of them were affected by a combination of APE and hypermobile upper lip (HUL). Based on 183 APE-affected teeth, the prevalence of APE types and subtypes was as follows: APE1A (96; 19.3%), APE1B (78; 15.9%), APE2A (8; 1.6%), and APE2B (1; 0.2%). Positive correlations were found between keratinized gingival width (KGW) and bone thickness (BT), while negative correlations were observed between gingival thickness (GT) and BT. CONCLUSION: Shorter CCL and CEJ-BC were the highlighted features of APE. APE affected approximately half of the gummy smile patients, with most of them presenting with a combination of HUL. Almost teeth affected by APE were classified as Type I, with a nearly equal distribution between subtypes A and B. CLINICAL RELEVANCE: The clinical and radiographic features of APE contribute to a better understanding of this condition and facilitate the management of patients affected by APE. Approximately half of gummy smile patients will require multidisciplinary treatment.

Assessment of gingival translucency at the mandibular incisors with two different probing systems. A cross sectional study.

OBJECTIVES: Increasing evidence indicates that the thickness of periodontal soft tissues plays an important role in various clinical scenarios, thus pointing to the need of further clinical research in this area. Aim of the present study was to assess gingival thickness at the mandibular incisors by translucency judgement with two different probes and to validate if these methods are comparable and applicable as diagnostic tools. MATERIALS AND METHODS: A total of 200 participants were included; gingival tissue thickness was measured by judging probe translucency at both central mandibular incisors, mid-facially on the buccal aspect of each tooth using a standard periodontal probe and a set of color-coded probe, each with a different color at the tip, i.e. Colorvue Biotype Probe (CBP). Frequencies and relative frequencies were calculated for probe visibility. Agreement between the standard periodontal probe and the CBP was evaluated via the kappa statistic. RESULTS: When the periodontal probe was visible, the frequency of CBP being visible was very high. Kappa statistic for the agreement between the standard periodontal probe and the CBP was 0.198 (71.5% agreement; p-value < 0.001) for tooth 41 and 0.311 (74.0% agreement; p-value < 0.001) for tooth 31, indicating a positive association of the two methods. CONCLUSIONS: An agreement that reached 74% was estimated between the standard periodontal probe and the color-coded probe at central mandibular incisors.  CLINICAL RELEVANCE: In the context of the present study, the two methods of evaluating gingival thickness seem to produce comparable measurements with a substantial agreement. However, in the 1/4 of the cases, the visibility of the color-coded probe could not assist in the categorization of the gingival phenotype.

Relationship between soft tissue dimensions and tomographic radial root position classification system for immediate implant installation.

The aim of this study was to evaluate the relationship between soft tissue dimensions and radial root position (RRP) classification for immediate implant placement on maxillary anterior teeth. Maxillary anterior teeth (n = 420) were analyzed in the radial plane of cone beam computed tomography (CBCT) scans. Each tooth was classified according to its RRP: class I, (IA, IB); class II (IIA, IIB) class III; class IV, and class V. Soft tissue thickness at different landmarks, supracrestal soft tissue height, and crestal bone thickness were measured in CBCT. Keratinized tissue width was clinically measured. Gingival phenotype (thick or thin) was evaluated by transparency of the periodontal probe and at the landmark 2 mm from the gingival margin in CBCT. Class I tooth position accounted for 31.7%, class II for 45%, class III for 13.3%, class IV for 0.5%, and class V for 9.5%. The gingival phenotype was associated with RRP (χ2 test, p < 0.05). Soft tissue dimensions were significantly different over RRP classes (ANOVA and Tukey tests, p < 0.05). Types IA and IIA presented both thick soft and hard tissues. When planning immediate implants in the anterior maxilla, soft tissue dimensions evaluation should be incorporated into RRP classification to increase the accuracy and predictability of treatment outcomes.

Comparative evaluation of pinhole surgical technique with and without A-PRF in the treatment of multiple adjacent recession defects: A clinico radiographic study.

BACKGROUND: To evaluate and compare efficacy of pinhole surgical technique (PST) alone and with advanced platelet rich fibrin (A-PRF) in the management of bilateral multiple adjacent gingival recession defects (MAGRD). METHODS: One hundred and sixty five MAGRD were randomly assigned to control group (treated with PST) and test group (PST with A-PRF). Clinical parameters of gingival recession depth (GRD), gingival recession width (GRW), width of keratinised gingiva (WKG), complete root coverage (CRC) and gingival thickness (GT) on ST-CBCT was measured at 2, 4 and 6 mm apically from the gingival margin. Also, root coverage aesthetic score and patient satisfaction ratings were recorded at baseline, 6 and 12 months postoperatively. RESULTS: Substantial reduction in GRD (Test: 1.29 ± 0.69 mm and Control 0.98 ± 0.30 mm) (p < 0.001) and GRW (Test: 2.03 ± 0.90 mm and control 1.73 ± 0.99 mm) (p < 0.05) with associated gain in WKG and GT was observed (p < 0.001). Mean GT values were increased in both the groups at 2, 4 and 6 mm from the crest. Comparison of Test and Control groups yielded significant reductions in GRD (-0.17 ± 0.56 mm) and WKG (0.73 ± 1.07 mm) favoring the Test group (p < 0.05). Similar increase in GT was observed with better results in Test than control group. (p < 0.001). CONCLUSION: Both groups exhibited sound clinical outcomes with test group offering better resolution of MAGRD in comparison to control group. Also, it enhances clinical and therapeutic end results in terms of attaining reduction in GRD and GRW along with greater gain in KTW and GT. CLINICAL SIGNIFICANCE: PST as a minimally invasive approach has numerous benefits, some of which include the absence of scarring and improved aesthetics linked to faster wound healing. The addition of A-PRF enhances the intended therapy outcomes, which is beneficial for both patients and professionals in the field of periodontics.

Assessment of the correlation between supracrestal gingival tissue dimensions and other periodontal phenotypes components via the digital registration method: a cross­sectional 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).

A comparative study of the application of three digital imaging techniques to assess the thickness of the palatal mucosa of the maxillary anterior teeth.

BACKGROUND: This study highlights the need for precise and efficient methods to measure palatal mucosal thickness in the maxillary anterior teeth, particularly for soft tissue augmentation in the aesthetic zone. The research evaluates three digital imaging techniques, suggesting that Cone Beam Computed Tomography (CBCT) combined with intraoral scanners (IOS) is a promising approach for reliable clinical assessment. METHODS: Ten volunteers with healthy periodontium were selected, and three methods were employed: CBCT-based indirect gingival imaging, modified soft tissue CBCT (ST-CBCT), and CBCT combined with IOS. Measurements of palatal mucosal thickness were taken at multiple points along the palatal gingival margin. Statistical analysis included Bland-Altman plots for method agreement and intraclass Correlation Coefficient (ICC) analysis for reliability. All measurements were standardized, repeated for consistency, and accurate to 0.01 mm to ensure reliability. RESULTS: The Bland-Altman plots showed that less than 5% of the points for palatal mucosal thickness differences measured by the gingival indirect radiographic method, modified ST-CBCT, and CBCT combined with IOS were located outside the 95% limits of agreement (LoA). The mean value of the differences was within 0.2 mm, indicating good clinical agreement among the three methods. The inter- and intra-study ICC values for palatal mucosal thickness measurements of the maxillary anterior teeth using the three CBCT methods were greater than 0.75 (P < 0.001), demonstrating reproducibility. CONCLUSIONS: Based on the evaluation of three digital imaging techniques, this study indicates that the combination of CBCT with IOS is a feasible method for measuring palatal mucosal thickness in the maxillary anterior teeth and demonstrates good reproducibility.

[Assessment of the condition of organs and tissues of the oral cavity in people with dentition defects against the background of metabolic syndrome]. / Otsenka sostoyaniya organov i tkanei rta u lits s defektami zubnykh ryadov na fone metabolicheskogo sindroma.

OBJECTIVE: The aim of the study is comparative analysis of the condition of oral organs and tissues in people with metabolic syndrome (MS) of varying severity before orthopedic dental rehabilitation based on dental implants. MATERIAL AND METHODS: 255 patients (151 women and 104 men) aged from 35 to 65 years were examined. 3 groups were formed: 2 study groups and a comparison group. Groups 1 and 2 included individuals with excess body weight and MS. The control group consisted of 88 people without MS. An index assessment of the condition of the periodontium and tissue structures of the alveolar bone (according to cone-beam computed tomography), microcirculation in the gingival mucosa was carried out using laser Doppler flowmetry. RESULTS: The analysis of the periodontal condition indicators showed that in all groups of patients with MS, periodontal pathology occurred, the value of which was significantly higher than in patients of the control group (p <0.05). The analysis of bone tissue according to CBCT data showed that the most favorable conditions (type 1 and type 2 of bone according to Misch) for dental implantation are found in people without MS, respectively 3.5% and 35.1% of cases. The intensity of blood flow (σ) was 21.2% lower in group 1 and 48% in group 2, compared with the control group. Vasomotor activity (Kv) was 13.2% lower in the first group and 35% lower in the second group. A decrease in amplitudes in the area of all rhythms in the LDF gram was found: low-frequency - by 15.6%, high-frequency - by 16.9%, pulse - by 3.6%. CONCLUSION: Changes occurring in the organs and tissues of the mouth against the background of MS of varying severity lead to a decrease in tissue perfusion with blood and blood flow activity, a local decrease in bone density, and as a result, pathological changes in periodontal tissues. Before performing dental rehabilitation, it is necessary to take into account all the risks of possible complications caused by the general condition of organs and systems of people with MS.

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 .

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.

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.

Morphological changes in alveolar bone thickness and height after orthodontic proclination or labial movement combined with autogenous soft tissue grafting: a CBCT evaluation.

BACKGROUND: Autogenous soft tissue grafting is indicated in thin gingival biotypes before orthodontic proclination or labial movements to increase the keratinized gingiva and prevent gingival recession. However, its effect on local alveolar bone remodeling is unclear. The aim of this study was to investigate the effects of autogenous soft tissue grafting on local alveolar bone after orthodontic proclination or labial movements. METHODS: Sixteen patients with a thin scalloped gingival biotype, narrow keratinized gingiva, or thin cortical bone requiring orthodontic proclination or labial movement of teeth were included. Cone-beam computed tomography (CBCT) images were obtained before grafting and at least 6 months after surgery. Sixty mandibular teeth were included, and the vertical bone level and horizontal labial bone thickness were measured. The results were compared using paired t-tests or Wilcoxon signed-rank test. RESULTS: The horizontal labial bone thickness increased, especially at 6 mm below the cementoenamel junction (CEJ) in the mandibular central and lateral incisors (P < 0.05). The total alveolar bone area of the canines, first premolars, and second premolars increased at 3, 6, and 9 mm below the CEJ, respectively, and the differences were statistically significant (P < 0.05). Additionally, vertical bone height increased minimally on the labial side, but the differences were not statistically significant (P > 0.05). CONCLUSIONS: New bone regeneration was observed on the labial (pressure) side after autogenous soft tissue grafting, which may represent a mechanism to effectively prevent gingival recession and maintain periodontal health. IRB APPROVAL: All the experimental procedures involving humans in this study were approved by the Medical Ethics Committee of Xiangya Stomatological Hospital, Central South University ( No. 20190048).

Evaluation Of Gingival Biotype And Recession Following Non-Surgical Periodontal Treatment Using 3-Dimensional Scan Methods.

The study evaluated the position of gingival margins in anterior teeth using clinical and 3-dimensional (3D) optical scanning method among patients subjected to non surgical periodontal treatment (NSPT). A single arm, longitudinal study was undertaken at the Archway Dental Center, University of Manchester, UK. History and clinical examination were done. Gingival recession, attachment loss (AL), and periodontal probing depth (PD) were recorded at baseline and 12-weeks follow-up. NSPT was done using hand and ultrasonic instruments. Impressions were made, the resultant gypsum models were scanned to generate 3D images. The change in the gingival level and thickness of facial gingiva were assessed. Out of eight patientsrecruited, three were lost to follow up. The 3D scan showed a poor correlation with the clinical assessment of gingival recession in anterior teeth following NSPT (r=- 0.0089). Recession did not improve after NSPT (p= 0.20).

Gingival thickness threshold and probe visibility through soft tissue: a cross-sectional study.

OBJECTIVES: The aim was to retrieve the threshold of gingival thickness (GT), where the attribute of gingival translucency through probe visibility was altered. METHODS: In 200 patients, the soft tissue thickness was evaluated at both central mandibular incisors using ultrasound quantification (USD). Additionally, probe visibility was determined using a standard periodontal probe (PB) (CPU 15 UNC, Hu-Friedy), inserted 1 mm deep into the gingival sulcus. Frequencies and relative frequencies were calculated. Repeatability analyses and receiver operating characteristics (ROC) were conducted to determine the USD cut-off point for probe visibility. RESULTS: Regression model indicated that the probe was not visible at a thickness of 0.82 mm for the mandibular left central incisor (95% CIs 0.77, 0.86) and became visible at a thickness of 0.69 mm (95% CIs 0.65, 0.72). The respective values for the mandibular right central incisor were 0.82 mm (95% CIs 0.77, 0.87) and 0.70 mm (0.68, 0.74). ROC analysis confirmed the retrieved regression results by indicating the best fitting balance for specificity and sensitivity at a thickness of 0.8 mm for both mandibular incisors. CONCLUSIONS: In the frame of the current study, the data revealed that gingiva becomes non-transparent at a thickness of approximately 0.8 mm. CLINICAL RELEVANCE: Probe visibility at mandibular incisors for the discrimination between thin and thick soft tissues was correlated with a gingival thickness of 0.8 mm and a high repeatability.

Assessment of gingival thickness in the maxillary anterior region using different techniques.

OBJECTIVES: Gingival phenotype is closely related to treatment success and aesthetic results in the maxillary anterior region. Several methods were proposed to measure the dimensions of the gingival tissue. This study aimed to evaluate the gingival thickness using clinical and radiographic techniques and to explore the association between gingival thickness and gingival phenotypes classified by color-coded phenotype probes. MATERIALS AND METHODS: The gingival thickness of 86 periodontally healthy maxillary anterior teeth was assessed using transgingival probing (TGP) and cone-beam computed tomography (CBCT). The gingival phenotype was classified as thin, medium, thick, or very thick by transparency of the color-coded probes through the gingival sulcus. The labial alveolar bone thickness was measured on CBCT images. The keratinized tissue width (KTW) was recorded. RESULTS: Good to excellent agreement was found between TGP and CBCT regarding the thickness of the gingiva (p<0.001). There was a very high correlation between the phenotypes determined by color-coded probes and the gingival thickness measured by TGP (r=0.953, p<0.001). KTW was significantly higher in thick and very thick phenotype groups compared with thin phenotype group. CONCLUSION: Cone-beam computed tomography images and the probe transparency method with color-coded probes are reliable for identifying the gingival phenotype in the maxillary anterior region, based on comparisons to direct transgingival probing. CLINICAL RELEVANCE: The assessment of the gingival phenotype is essential, especially in the aesthetic zone, to obtain predictable and favorable clinical outcomes in various dental procedures. The newly introduced color-coded probes comprise a non-invasive and reliable method for this.

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.

Accuracy of digital complete-arch, multi-implant scans made in the edentulous jaw with gingival movement simulation: An in vitro study.

STATEMENT OF PROBLEM: The use of computer-aided design and computer-aided manufacturing (CAD-CAM) technologies is widely established, with single restorations or short fixed partial dentures having similar accuracy when generated from digital scans or conventional impressions. However, research on complete-arch scanning of edentulous jaws is sparse. PURPOSE: The purpose of this pilot in vitro study was to compare the accuracy of a digital scan with the conventional method in a workflow generating implant-supported complete-arch prostheses and to establish whether interference from flexible soft tissue segments affects accuracy. MATERIAL AND METHODS: An edentulous maxillary master cast containing 6 angled implant analogs was used and digitized with mounted scan bodies by using a high-precision laboratory scanner. The master cast was then scanned 10 times with 4 different intraoral scanners: TRIOS 3 with a complete-arch scanning strategy (TRI1) or implant-scanning strategy (TRI2), TRIOS Color (TRC), CEREC Omnicam (CER), and CEREC Primescan (PS). The same procedure was repeated with 4 different levels of free gingiva (G0-G3). Ten conventional impressions were obtained. Differences in implant position and direction were evaluated at the implant shoulder as mean values for trueness and interquartile range (IQR) for precision. Statistical analysis was performed by using the Kruskal-Wallis and post hoc Conover tests (α=.05). RESULTS: At G0, position deviations ranged from 34.8 µm (IQR 23.0 µm) (TRC) to 68.3 µm (12.2 µm) (CER). Direction deviations ranged from 0.34 degrees (IQR 0.18 degrees) (conventional) to 0.57 degrees (IQR 0.37 degrees) (TRI2). For digital systems, the position deviation ranged from 48.4 µm (IQR 5.9 µm) (PS) to 76.6 µm (IQR 8.1 µm) (TRC) at G1, from 36.3 µm (IQR 9.3 µm) (PS) to 79.9 µm (IQR 36.1 µm) (TRI1) at G2, and from 51.8 µm (IQR 14.3 µm) (PS) to 257.5 µm (IQR 106.3 µm) (TRC) at G3. The direction deviation ranged from 0.45 degrees (IQR 0.15 degrees) (CER) to 0.64 degrees (IQR 0.20 degrees) (TRC) at G1, from 0.38 degrees (IQR 0.05 degrees) (PS) to 0.925 degrees (IQR 0.09 degrees) (TRI) at G2, and from 0.44 degrees (IQR 0.07 degrees) (PS) to 1.634 degrees (IQR 1.08 degrees) (TRI) at G3. Statistical analysis revealed significant differences among the test groups for position (G0: P<.001; G1: P<.05; G2: P<.001; G3: P<.001) and direction (G0: P<.005; G1: P<.001; G2: P<.001; G3: P<.001). CONCLUSIONS: Without soft tissue interference, the accuracy of certain digital scanning systems was comparable with that of the conventional impression technique. The amount of flexible soft tissue interference affected the accuracy of the digital scans.

Maxillary anterior gingiva and dentoalveolar changes after en-masse retraction between thick and thin gingival biotypes.

INTRODUCTION: This study compared the changes of gingiva and alveolar bone parameters, including cortical and cancellous bones between thick and thin gingival biotypes after en-masse retraction. METHODS: Thirty-two adult subjects (mean age, 20.6 years) with maxillary anterior teeth protrusion and proclination were studied and divided into 2 equal groups: thick gingival biotype (TKB) and thin gingival biotype (TNB). Maxillary anterior teeth were retracted using nickel-titanium coil springs at 150 g of force bilaterally for 4 months. Lateral cephalograms, study models, and cone-beam computed tomography scans were taken before retraction and 3 months after 4 months of retraction. Nonparametric tests compared the changes within the groups at these periods and between the groups. RESULTS: The gingiva gained thickness and length (P <0.01) on the labial and palatal sides. The gingival thickness gained more on the palatal side (P <0.01), whereas the length gained equally in both groups. Labial alveolar bone showed increased thickness and height (P <0.01) as opposed to the palatal alveolar bone that presented with loss of thickness and height (P <0.01). The height loss occurred more in TNB (P <0.01). Labial cortical bone increased in thickness and height (P <0.01), whereas palatal cortical bone thinned (P <0.01) at levels in which no cancellous bone was present at the crestal level for TKB and the crestal and midroot levels for TNB. TKB showed slower incisor movement and less retroclination than the TNB (P <0.01) with minimal incisor extrusion. CONCLUSIONS: Favorable gingiva and labial bone responses after en-masse retraction were found in both gingival biotypes, whereas more palatal alveolar bone height loss was presented in TNB. Cortical bone thickness decreased when cancellous bone was absent.

Gingival shape analysis using surface curvature estimation of the intraoral scans.

BACKGROUND: Despite many advances in dentistry, no objective and quantitative method is available to evaluate gingival shape. The surface curvature of the optical scans represents an unexploited possibility. The present study aimed to test surface curvature estimation of intraoral scans for objective evaluation of gingival shape. METHODS: The method consists of four main steps, i.e., optical scanning, surface curvature estimation, region of interest (ROI) definition, and gingival shape analysis. Six different curvature measures and three different diameters were tested for surface curvature estimation on central (n = 78) and interdental ROI (n = 88) of patients with advanced periodontitis to quantify gingiva with a novel gingival shape parameter (GS). The reproducibility was evaluated by repeating the method on two consecutive intraoral scans obtained with a scan-rescan process of the same patient at the same time point (n = 8). RESULTS: Minimum and mean curvature measures computed at 2 mm diameter seem optimal GS to quantify shape at central and interdental ROI, respectively. The mean (and standard deviation) of the GS was 0.33 ± 0.07 and 0.19 ± 0.09 for central ROI using minimum, and interdental ROI using mean curvature measure, respectively, computed at a diameter of 2 mm. The method's reproducibility evaluated on scan-rescan models for the above-mentioned ROI and curvature measures was 0.02 and 0.01, respectively. CONCLUSIONS: Surface curvature estimation of the intraoral optical scans presents a precise and highly reproducible method for the objective gingival shape quantification enabling the detection of subtle changes. A careful selection of parameters for surface curvature estimation and curvature measures is required.