Maxillary Left Central Incisor Research Articles

Fracture resistance of cement-retained lithium disilicate implant-supported crowns: Effect of material used for two-piece abutments.

This study compared the fracture strength of single lithium disilicate implant-supported crowns fabricated on two-piece abutments with various materials: ceramic-reinforced PEEK, zirconia, and lithium disilicate. Thirty-six implants were embedded in acrylic cylinders. A two-piece abutment and a crown were designed following a pre-operation scan for a maxillary left central incisor. The designed crown was used to fabricate 36 lithium disilicate crowns. The designed abutment was used to manufacture 36 abutments from 3 materials, 12 each: (A) zirconia; (B) lithium disilicate; and (C) ceramic-reinforced PEEK. Abutments were surface treated and bonded on the titanium base abutments with resin cement. Then, lithium disilicate crowns were bonded on the assigned abutments. Specimens were then subjected to dynamic loading for 1,200,000 cycles. The fracture strength (N) of the assembly was assessed using a universal testing machine. One-way ANOVA followed by multiple comparison tests was used to evaluate the effect of abutment material on the fracture strength of single implant-supported restorations at a significance of .05. The average fracture strength for the groups with zirconia, PEEK, and lithium disilicate two-piece abutments were 1362N ± 218N, 1235N ± 115N, and 1472N ± 171N, respectively. There was a significant (p < 0.05) difference in fracture strength among the groups. The lithium disilicate group had significantly higher fracture strength (p = 0.0058) than the group with PEEK; however, there was no significant (p > 0.05) difference between the other groups. Two-piece abutments restored with lithium disilicate crowns investigated in the study have the potential to withstand the average physiological occlusal forces in the anterior region.

Management of luxation injuries in line with International Association of Dental Traumatology guidelines – Two case reports

Luxation injuries represent significant traumatic events for permanent teeth. This article presents the management of intrusive and extrusive luxation injuries, following the International Association of Dental Traumatology (IADT) guidelines, through two case reports. The first case involves a 30-year-old female with an intruded maxillary left central incisor, managed through surgical extrusion, stabilization, and endodontic treatment. The second case features a 15-year-old female with an extruded maxillary left central incisor, repositioned and splinted. Follow-up examinations revealed the resolution of symptoms in both cases. These cases highlight the efficacy of IADT guidelines in diagnosing and treating luxation injuries, resulting in favorable outcomes.

Conservative management of lateral canal biofilm-related persistent intraoral sinus and other complications in traumatized, immature incisors: A case report with 30 months’ follow-up

Conservative or regenerative endodontic treatments are the preferred approaches for managing traumatized (vital or necrotic) immature permanent teeth in growing patients. Diagnosing pulp vitality preoperatively using sensitivity tests can be challenging, especially if multiple teeth are traumatized, potentially leading to the failure of the chosen endodontic treatment. Unexpected complications, such as persistent intraoral sinus related to the lateral canal (often not visible on conventional radiographs) and delayed periradicular bone healing, may also arise. This case report presents the successful conservative management of three traumatized incisors with such complications. A novel intracanal dressing method was used to treat a persistent intraoral sinus related to the lateral canal in the permanent maxillary left central incisor, which was unresponsive to traditional dressing materials and methods, thereby avoiding surgery or extraction. Additionally, delayed bone healing in response to revascularization treatment in the permanent maxillary right central incisor, and the initially involved vital permanent maxillary right lateral incisor, was addressed with re-revascularization and root canal treatment, respectively. This article discusses tailored management strategies and possible reasons for associated complications in traumatized teeth. It emphasizes the importance of high-quality radiographic images, pulp vitality tests based on blood oxygenation, understanding the presence of biofilm in lateral canals, modified dressing methods, appropriate dressing vehicles, and the necessity of patience in treating traumatic dental injuries. Keywords: Biofilm; Conservative Management; Pediatric Dentistry; Root Canal Medicaments; Teeth Injuries

Influence of Printing Angulation on the Accuracy (Trueness and Precision) of the Position of Implant Analogs in 3D Models: An In Vitro Pilot Study

Background: With CAD-CAM, dental models are often fabricated by additive manufacturing (AM) methods. Dental models for implant prostheses involve the manual placement of analogs, which could affect their final fit. Therefore, in this experimental in vitro study, the accuracy of the analogs’ position in models printed using AM methods was examined by comparing three different printing orientations. Methods: An STL file was obtained by scanning a master model with an implant placed in the maxillary left central incisor position. Three study groups (n = 10) with varying printing orientation parameters were obtained (0, 45, and 90 degrees). They were digitalized with a laboratory scanner and evaluated with an analysis metrology program. Differences between 3D datasets were measured using the RMS for trueness and SD RMS for precision. The data were statistically analyzed using the ANOVA test at a significance level of p &lt; 0.05, followed by the Bonferroni post hoc test. Results: The 45-degrees group showed the best results. Regarding trueness, statistically significant differences were found between the 45- and 90-degrees groups (p &lt; 0.005). In terms of precision, statistically significant differences appeared between the 45- and 0-degrees groups (p &lt; 0.011) and between the 45- and 90-degrees groups (0.003). Conclusions: The printing angulation parameter affects the accuracy of 3D-printed models. Implant models manufactured at 45 degrees of printing angulation are more accurate than those printed at 0 or 90 degrees.

A Comparative Study to Check the Accuracy of Tooth Shade Selection With Standardized Digital Photographs and a Spectrophotometer.

The success of any dental prosthesis depends on aesthetics and function. A proper shade selection is a prime requisite for providing aesthetics to dental patients. This study aims to compare the photographic method of shade selection with that of a digital spectrophotometer. The study included 50 participants. The primary inclusion criterion was the presence of the maxillary left central incisor without a history of restorative or endodontic procedures. The shade of the left maxillary central incisor was determined using the VITA Easyshade V spectrophotometer (VITA Zahnfabrik, BadSäckingen, Germany) and the digital photography method for all the selected participants. The CIELAB colour space utilizes three values (L*, a*, and b*) to objectively measure colour. While the digital photography approach used Adobe Photoshop software (Adobe Systems Incorporated, San Jose, CA) to report solely the L*, a*, and b* values, the spectrophotometer reported the L*, a*, and b* values along with the actual shade. After obtaining the values of L*, a*, and b*, ΔE, which is their difference, was calculated using a standard formula. Statistical analysis was carried out by using Student's t-test and proportion z-test. When the comparison of the L*a*b* values was done, Student's t-test showed similar (P>0.05) L(t=0.16, P=0.872), a (t=0.52, P=0.607), and b (t=0.23, P=0.820) values between the two groups; that is, they did not differ significantly or showed perfect matching. There was agreement (ΔE≤2) in 42 (84.0%) cases and disagreement (ΔE>2) in eight (16.0%) cases. The proportion z-test showed an agreement of 84.0%, which was statistically highly significant (z=20.44, P<0.001). The true shade of the teeth can be depicted using standardized digital images.

Surgical Management of Radicular Cyst with the Application of a Natural Platelet Concentrate and Ostoden: A Case Report

ABSTRACT The most frequent cystic lesions that affect the jaw are radicular cysts. The current case report describes the surgical management of a radicular cyst in the periapical region of maxillary central and lateral incisors, and highlights the efficacy of natural platelet concentrate [platelet-rich fibrin (PRF)] along with Ostoden bone graft material used for postoperative healing. A 46-year-old male patient presented to the department with swelling in the palatal aspect of the maxillary anterior region. On radiographic examination, a radiolucent periapical lesion was evident in relation to the left maxillary central and lateral incisor. In the maxillary anterior region, root canal therapy was performed, followed by periapical surgery, and PRF with Ostoden bone graft was placed in the surgical site to initiate the healing at a faster rate. The patient was recalled at follow-ups after 7 days, 3, 6, and 9 months. No symptoms such as pain, inflammation, or discomfort were observed during the review period.

Multidisciplinary Treatment: Follow-Up of Dental Autotransplantation for 10 Years.

The objective is to present a clinical case of dental autotransplantation managed with surgery, orthodontics, endodontics, periodontics, and aesthetic rehabilitation. A 10-year-old boy sought treatment after avulsion of the maxillary left central incisor, which was not reimplanted. Based on anamnesis, clinical examination, and complementary examinations, agenesis of the maxillary and mandibular second premolars except the mandibular right second premolar was observed. After a multidisciplinary planning, the space in the maxillary left central incisor region was opened to receive the transplanted mandibular right second premolar. The receptor site was created in a single surgical procedure. Pulp necrosis was noted in the transplanted tooth, which was treated endodontically, and the agenesis spaces were closed using fixed orthodontic appliances. After removing the appliance, gingivectomy with osteotomy was performed in the maxillary right central incisor and the transplanted tooth regions to harmonize the height and shape of the gingival contour. Next, aesthetic readjustment was performed with tooth whitening, using office and home techniques, followed by microabrasion of the vestibular surface of the maxillary right central incisor. Direct composite resin restorations were placed in the maxillary incisors, and the teeth were rehabilitated using incisal and palatal guides. A multidisciplinary approach is essential for reestablishing the function and aesthetics of complex cases involving dental autotransplantation.

Comparison of three-dimensional position of maxillary dentition model treated with two digital transfer methods

Objective: To compare and evaluate the difference in maxillary dentition position using an anatomical facebow and jaw movement analyzer. Methods: From March to May 2023, 15 medical interns from Yantai Stomatological Hospital were recruited, including 9 males and 6 females, aged 20-25 years. Digital models and plaster models of maxillary dentition were obtained from the 15 medical interns. The anatomical facebow group (AFB) and jaw movement analyzer group (JMA) were used to transfer the position of the maxillary dentition to the virtual articulator. The virtual occlusal articulator module of exocad denture design software was used to measure the inclination angle of the occlusal plane of the two groups, the distance between the mesio-incisal angle of the left maxillary central incisor and the lateral center point of the lateral condylar sphere of the virtual occlusal articulator, the distance between the mesial buccal cusp of the maxillary first molar and the lateral center point of the lateral condyle sphere of the virtual articulator. The same marks (mesial incisor point of left maxillary central incisor and mesial buccal cusp point of both maxillary first molars) were measured in two groups of maxillary dentition, and the root-mean-square error between 3 points was calculated. Results: The occlusal plane inclination angle in AFB group (9.11°±3.85°) was significantly larger than that in JMA group (4.94°±2.69°) (t=10.45, P<0.001). There were significant differences between AFB and JMA groups. The distances from the mesial cusp of the left first molar to the lateral center of the left condylar, from the mesial cusp of the left maxillary central incisor to the lateral center of the left condylar[(91.75±3.05), (129.09±4.60) mm]were significantly smaller than those in the JMA group[(95.68±5.45), (132.41±5.64) mm](t=-4.48, P=0.001; t=-4.21, P=0.001). In both groups of models, the distance of the mesial cusp of the left maxillary central incisor was (8.81±2.56) mm, and the distance between mesial buccal cusp of maxillary left first molar was (7.56±2.49) mm, the distance between mesial buccal cusp of maxillary right first molar was (7.13±2.77) mm; the root mean square error was (7.93± 2.94) mm. Compared with 0, the difference was statistically significant (t=10.45, P<0.001). Conclusions: There were differences between the two methods (anatomical facebow and the jaw movement analyzer) for transferring the maxillary dentition position to the three-dimensional space position of the virtual articulator.

Kvaal’s dental age estimation method applied to Brazilian adults—a cross-sectional test of validity

BackgroundDental age estimation of adults is a challenging procedure in forensic odontology. Radiographic techniques have enabled non-invasive age estimation of adults since the 90’s. Kvaal’s method based on the deposition of secondary dentin has demonstrated broad applicability in several populations. Population-specific studies with this method, however, are scarce in South America. This study tested the validity of Kvaal’s method in a sample of radiographs of Brazilian adults. The sample consisted of 192 periapical radiographs of 106 females (55.2%) and 86 males (44.8%) with ages between 20 and 80 years old. The permanent maxillary right (n = 84, 43.8%) and left (n = 108, 56.2%) central incisors were assessed based on Kvaal’s method.ResultsLin’s coefficient of concordance between estimated (EA) and chronological (CA) ages was 0.800 (IC95% = 0.753; 0.847) (p < 0.001). The mean difference between EA and CA was − 2.84 years (p < 0.001). For females and males, separately, the mean differences between EA and CA were − 3.82 years (CI95% = − 5.38; − 2.25) (p < 0.001) and − 1.86 years (CI95% = − 3.56; − 0.17) (p = 0.031), respectively. Underestimations were predominant and increased with time.ConclusionAfter 28 years of the original publication, Kvaal’s method remains reliable for non-invasive dental age estimation of adults, especially for the analysis of the permanent maxillary central incisors of Brazilian individuals.

A Case of Anterior Single Tooth Implant with Fractured Zirconia Abutment due to Trauma.

In recent years, a wide variety of materials have been used in dental implant treatment. In selecting the superstructures and abutments to be used it is important to consider their potential effect on the stability and durability of the planned implant. Excessive force applied to an implant during maintenance commonly results in complications, such as fracture of the superstructure or abutment, and loosening or fracture of the screws. This report describes a case of implant treatment for a 23-year-old man with esthetic disturbance due to trauma to the maxillary anterior teeth. The left maxillary central incisor could not be conserved due to this trauma, which had been caused by a traffic accident. After extraction, the tooth was restored with an anterior bridge. The crown of the left maxillary lateral incisor was fractured at the crown margin and, at the patient's request, implant treatment was selected as the restorative treatment for the missing tooth. A thorough preoperative examination was performed using placement simulation software. One titanium screw-type implant was placed in the maxillary left central incisor under local anesthesia. An all-ceramic crown with a zirconia frame was placed as a screw-fixed direct superstructure. At one year postoperatively, however, the superstructure and abutment became detached due to trauma. The fractured zirconia abutment was removed and replaced with a remanufactured abutment and superstructure. The patient has reported no subsequent dental complaint over the last 11 years. In this case, a surface analysis of the fractured zirconia abutment was performed. The scanned images revealed a difference in the fracture surfaces between the tensile and compressive sides, and electron probe microanalysis demonstrated the presence of titanium on the fracture surface. It was inferred that the hard zirconia abutment had scraped the titanium from the internal surface of the implant.

Invasión radicular del conducto incisivo durante el tratamiento de ortodoncia debido a un torque radicular palatino excesivo. Reporte de un caso

Aim: Patients presenting with bimaxillary proclinati-on often have an accompanying maxillary alveolar pro-cumbency. Case Report: Posterior relocation of the anterior alveolus is an important mechanism to reduce this prominence. Torquing the maxillary incisor roots palatally allows the anterior alveolus (point A) to remodel distally. This technique is non-invasive and therefore has good patient acceptance. Results: The following case report demonstrates the involvement of the incisive canal due to increased palatal root torque of the maxillary left central incisor root Conclusions: The use of 3D imaging in the diagnosis, its clinical complications as well as their remedial measures is also discussed. Keywords: Incisive canal; Root resorption; Torque; Orthodontics; Maxilla; Cone-beam computed tomography.

Tooth avulsion and its consequences: Case series

On an average about 30% of all school children suffer traumatic dental injury in primary dentition, whereas 22% suffer in permanent dentition. Avulsion is a serious injury which causes damage to dental and supportive tissues, ranging from 0.5-16 % among dental injuries and it mostly occurs in maxillary incisors. Tooth avulsion can be described as the complete displacement of the entire tooth out of its alveolar socket as a result of force generated due to external injury. The accepted management of choice is immediate replantation of the tooth into its socket provided dental facilities are nearby available and if it is delayed, placement of the tooth in an appropriate storage media until dental treatment can be initiated. Replantation of avulsed incisors in children has shown successful prognosis. The replanted teeth with time may lead to ankylosis followed by inflammatory or replacement resorption, as immediate replantation is practically rare. This case series showcases management of an avulsed maxillary left central incisor which was kept in patient oral cavity from the moment of trauma until its replantation in a eight year old boy. The avulsed tooth was replanted back into the alveolar socket after completion of endodontic treatment extra orally in same visit and splinted with composite resin. The other 2 case reports are 01 &amp; 1.5 years follow up of replantated avulsed central incisors. During the follow up of these cases it was found that the teeth reported in these cases have remained in a stable, functional position but revealed external root resorption &amp; replacement resorption even after completion of endodontic treatment. The amount of damage to tooth and supporting structures like bone, gingiva, emergency management and follow up period play a vital role in the prognosis of the avulsed tooth. It can be recommended to keep the avulsed tooth in saline solution as it is easily available when more appropriate storage media like HBSS are not available immediately.

Visualization of airborne droplets generated with dental handpieces and verification of the efficacy of high-volume evacuators: an in vitro study

BackgroundThe COVID-19 pandemic led to concerns about the potential airborne transmission of the virus during dental procedures, but evidence of actual transmission in clinical settings was lacking. This study aimed to observe the behavior of dental sprays generated from dental rotary handpieces and to evaluate the effectiveness of high-volume evacuators (HVEs) using laser light sheets and water-sensitive papers.MethodsA dental manikin and jaw model were mounted in a dental treatment unit. Mock cutting procedures were performed on an artificial tooth on the maxillary left central incisor using an air turbine, a contra-angle electric micromotor (EM), and a 1:5 speed-up contra-angle EM (×5EM). Intraoral vacuum and extraoral vacuum (EOV) were used to verify the effectiveness of the HVEs. The dynamics and dispersal range of the dental sprays were visualized using a laser light sheet. In addition, environmental surface pollution was monitored three-dimensionally using water-sensitive papers.ResultsAlthough the HVEs were effective in both the tests, the use of EOV alone increased vertical dispersal and pollution.ConclusionsThe use of various types of HVEs to reduce the exposure of operators and assistants to dental sprays when using dental rotary cutting instruments is beneficial. The study findings will be helpful in the event of a future pandemic caused by an emerging or re-emerging infectious disease.

Interdisciplinary treatment for an adolescent with fusion of the left maxillary lateral and central incisors: A clinical report

The interdisciplinary treatment provided for a 12-year-old boy with fusion of his left central and lateral incisors and concomitant distal space loss is described. His treatment was initiated with orthodontic therapy followed by endodontic treatment of the fused tooth. A conservative zirconia and porcelain cantilevered bonded fixed dental prosthesis was then completed to replace his left lateral incisor.

Accuracy of computer-aided design trial restorations fabricated with different digital workflows

Trial restorations are a versatile tool for visualizing the esthetic treatment plan and should be an accurate replica of the planned smile design. The accuracy of conventionally fabricated trial restorations has been investigated; however, studies on the accuracy of different digital workflows for trial restoration fabrication are lacking. The purpose of this in vitro study was to evaluate the accuracy of computer-aided design (CAD) trial restorations fabricated with different digital workflows. A patient in need of additive esthetic treatment was examined, and intraoral and extraoral photographs and intraoral digital scans were made, followed by 3D digital smile design using the exocad software program. The reference virtual design was converted into trial restorations (N=40) by using different digital workflows: subtractive manufacturing, additive manufacturing, additive manufacturing of 3D designed index, and silicone index on an additively manufactured cast. Fabricated trial restorations of all groups were scanned with a desktop scanner, providing a standard tessellation language (STL) file serving as the test data for each trial restoration. All the STL files of the test and reference data were imported into a reverse engineering software program to evaluate the 3D trueness of each workflow. Also, analog and digital 2D linear measurements (maxillary left central incisor height, maxillary left central incisor width, and intercanine width) were made to assess any dimensional alterations between the fabricated trial restorations and the reference digital smile design. A 1-way analysis of variance (ANOVA) was used to analyze the data followed by the Tukey post hoc test (α=.05). For 3D trueness measurements, root mean square (RMS) values representing the deviations between the fabricated trial restorations and the reference digital smile design varied significantly among the different groups (P<.001), with the highest mean deviation found in the group of additive manufacturing of 3D designed index (0.21 ±0.01mm), while the lowest mean value of deviation was found in the group of subtractive manufacturing (0.11 ±0.02mm). For both the digital and analog 2D linear measurements, post hoc pairwise comparisons showed the group of additive manufacturing of 3D designed index to have significantly higher values of deviation than the other groups in all assigned measurements (P<.001). The accuracy of CAD trial restorations was affected by the fabrication technique, and implementing conventional steps in the digital workflows of trial restoration fabrication may result in discrepancies that affect accuracy when compared with the reference design.

Biomimetic Post: An Innovative Approach to Reinforce Mutilated Maxillary Central Incisor - A Case Report

Ideal functional reconstruction of severely compromised anterior teeth is still a challenge for restorative dentistry. In this context a “Biomimetic Post” serves as a homologous solution for intraradicular rehabilitation of a fractured endodontically treated tooth by virtue of its biomimetic property. This case report highlights the successful esthetic and functional rehabilitation of maxillary central incisor through the preparation and adhesive cementation of a “Biomimetic Post”. A male patient aged 18 years presented with a traumatic dental injury sustained to the maxillary left central incisor. Conventional root canal therapy was initiated and apexification with mineral trioxide aggregate was done. Radicular post space was prepared and dentin post was fabricated from a freshly extracted, intact human canine. After checking for the adaptation of dentin post, it was cemented with glass ionomer cement. Follow up was done at regular intervals of three months. Keywords: Anterior tooth, Esthetic restoration, Intraradicular rehabilitation, Biomimetic post.

THREE YEARS FOLLOW UP REPLANTATION IN HEAVY SMOKER PATIENT: CASE REPORT

Tooth avulsion is different from all other dental injuries due to the extracorporeal situation with varying duration and degree of contamination of the teeth and the patient's systemic conditions. In a heavy-smoker patient, wound healing could be interrupted. Extra-alveolar handling, good replantation, and educating the patient could be the key to successful treatment of tooth avulsion, especially in a heavy smoker. The aim of this study is to discuss an avulsed tooth case that has been successfully treated by replantation in a heavy smoker. A 39-year-old female patient was refered to Siloam Hospital due to a dental trauma injury. The patient was in good general health, but she was a heavy smoker. Intraoral examination revealed that the maxillary left permanent central incisor was avulsed after the patient fell off in her bathroom. Replantation is a treatment of choice in this case. The avulsed tooth was stored in a saline solution. On one visit, root canal treatment was done on the avulsed tooth extra orally soon after the patient was refered to the AE department at Siloam Hospital. The avulsed tooth was replanted and fixed using an Erich arch bar to the previous position by finger pressure. Fix the Erich bar as far as possible to the distal and mesial of the avulsed tooth using circumferential wire in every single tooth. We decided to put the Erich bar from 15 to 25. The following oral hygiene cleaning, dietary instructions, and education to reduce or stop smoking during the healing process were given. Extra-alveolar handling, good replantation, good fixation, and adequate oral hygiene education are the keys to treating a tooth avulsion, even in a heavy smoker.

Management of Bilateral Foreign Objects in Immature Permanent Maxillary Central Incisors: A Case Report

AbstractTraumatic dental injuries are more commonly seen in children and it often results in a complicated crown fracture. This case is unique as foreign objects in the form of hand-sewing needles were accidentally lodged bilaterally in both maxillary central incisors. A 13-year-old patient was referred to the Dental Clinics at the College of Dentistry, Jazan University with a complaint of broken needles in her front teeth and a history of trauma 3 years ago. Although the patient had the habit of using a hand-sewing needle to remove the lodged food particles from the open pulp chamber, she was not able to recollect the incidence of needle separations. Radiographic examination revealed radiopaque objects in the middle third of the right maxillary central incisor (#11) and in the apical third of the left maxillary central incisor (#21). Tooth #11 was clinically diagnosed as pulp necrosis with chronic apical abscess and tooth #21 as pulp necrosis with asymptomatic apical periodontitis. The micro tweezer from the broken instrument removal kit (Zumax Medical Co.,Ltd., Jiangsu, China) was used to retrieve the separated needle pieces under the operating microscope. The open apices were managed by the formation of mineral trioxide aggregate apical plug, and the procedure of root reinforcement was achieved by bonded resin cement and fiber resin posts. Finally, teeth were restored with dual cure core build-up composite material and direct composite veneers. Recommendations are made to treat complicated crown fractures, especially in children on priority to minimize the risk of foreign object impaction.

A comparison of alveolar ridge mucosa thickness in completely edentulous patients.

The purpose of this cross-sectional clinical study was to determine and compare alveolar ridge mucosa thickness at crestal, buccal, and lingual locations of the maxillary and mandibular arches in completely edentulous patients using a dedicated, ultrasonic gingival scanner. Thirty-eight completely edentulous subjects were included in the study. In each subject, soft tissue thickness was measured at 28 sites of the edentulous ridge by a single calibrated examiner. Intra-observer reliability was calculated with Intraclass Correlation Coefficients by measuring 10 subjects twice, after 1 week. Measurements (mm) were taken at the buccal, lingual, and crestal aspects of the ridge with a dedicated ultrasonic scanner. Repeated measures ANOVA and paired t-tests were used to compare the mean buccal, lingual, and crestal soft tissue thicknesses at each site. The GeneralizedEstimating Equations model was used to study the effects of age, sex, and race. Confidence level was set to 95%. Mean tissue thickness ranged from 0.96 to 1.98mm with a mean of 1.63 ± 0.25mm. Intraclass Correlation Coefficients were > 0.97. No significant differences between buccal, crestal, and lingual sites were noted for the mandibular arch as well as at 4 sites on the maxillary arch (maxillary right second molar, maxillary right canine, maxillary left first premolar, maxillary left second molar). However, significant differences in soft tissue thickness were noted for all remaining maxillary sites. Race was found to be positively correlated with tissue thickness, with Black individuals showing a significantly greater thickness than Whiteindividuals at 4 sites (maxillary right first molar, maxillary left canine, mandibular right second premolar, mandibular right first molar). Age was found to be positively correlated with tissue thickness at 4 sites (maxillary left central incisor, maxillary left first molar, maxillary left second molar, mandibular left second premolar) and negatively correlated at 2 sites (mandibular right canine, mandibular right second molar). Female sex was positively (maxillary left second premolar, maxillary left second molar) and negatively (mandibular right canine) correlated, respectively, with tissue thickness at 3 sites. When data for anterior and posterior sites were respectively pooled, tissue thickness was significantly less at anterior sextant lingual and crestal sites, while no difference was seen for buccal sites. Statistically significant differences for alveolar ridge mucosa thickness were found at several sites in the maxilla and between anterior and posterior sextants for lingual and crestal sites in the maxillary and mandibular arches. Tissue thickness differences were also noted for race with Black individuals showing greater tissue thickness at some sites. Age and sex did not show a clear effect on tissue thickness. Recorded differences in tissue thickness were however small and appear of uncertain clinical significance.

Fingernail form as a post-extraction guide for selecting the maxillary central incisor tooth form in the Saudi Arabian population: A novel application of CAD software.

Human teeth and nails have demonstrated similar factors genetically, embryologically, and morphologically. The fingernail form may be used as a post-extraction guide for selecting the tooth form. To evaluate the correlation between the maxillary left central incisor tooth form with the left index, middle, and ring fingernails in the Saudi Arabian population. A descriptive cross-sectional study with purposive sampling was done among 200 Saudi participants. The maxillary left central incisor and the left index, middle, and ring fingernail were scanned using an intraoral scanner. The 3D digital images were converted to 3D models. The tooth form (tooth length, tooth width, and tooth shape) and nail form (nail length, nail width, and nail shape) were measured using the CAD software. Pearson's correlation coefficient and T-test were used for statistical analysis (P < 0.05). A significant correlation exists between tooth length and nail length, with a maximum correlation toward index nail length (P = 0.015). A significant correlation exists between tooth width and nail width, with a maximum correlation toward ring nail width (P = 0.002). A significant correlation exists between tooth length and nail length in females with a maximum correlation toward index nail length in females (P = 0.001). The mean percentage of similarity between tooth and nail shape (index, middle, and ring) in males and females shows a highly significant difference between them (P = 0.001). The results indicate that the tooth and nail shape are similar (70 to 90%) based on the criteria set by the software. A definite correlation exists between maxillary central incisor tooth form and fingernail form. The fingernail form may be used as a post-extraction guide for selecting the maxillary central incisor tooth form in the Saudi Arabian population.