Molar Area Research Articles

Assessment of fully digitalized workflow for implant-prosthetic rehabilitation in temporomandibular disorders patients: A clinical study

Digitalized workflow eliminates the need for the tray, impression materials, its decontamination, packaging and shipping, pouring with plaster, cast fabrication, mounting in an articulator, reducing storage spaces, and the risks of any loss or fracture of the plaster model is overcome by archiving on the computer. This clinical investigation aimed to evaluate the effectiveness of the fully digitalized rehabilitation [implant-supported prosthesis] method in partially edentulous patients and with TMD, using advanced software. Twelve patients requiring implant-supported prosthesis in the mandibular molar area with Temporomandibular disorders [TMD] were selected. The fully digitalized rehabilitation method with advanced software was used for rehabilitation. For each subject, Optical impressions, CBCT scan, and Digital recording of jaw movement data. Guided implant surgery and digitalized prosthetic rehabilitation; were performed. The effectiveness of the digitalized workflow was assessed by evaluating the changes in the joint symptoms before and after the end of the treatment, changes in the electromyographic tracings, the precision of the prosthetic artefact, assessed through the amount of chair adjustment operating time and the number of retouching/ modifications to be carried out before the completion of the work. The results showed that the mean operative time required in 12 patients was 9.42 min, significantly less than the time recorded in previous studies when the medium mean was 16.00 min. The mean number of touch-ups [adjustments] was less than 3, most of which were on the interproximal surfaces. There were no significant changes recorded in the electromyography tracings. There were also no changes in joint symptoms. It was found that this way of working was entirely reliable and significantly reduced operating times and the number of appointments. Digital flow is beneficial ei dysfunctional patients, not about improvements in temporomandibular symptoms but in times of operability and prosthetic retouching.

Influence of a new abutment design concept on the biomechanics of peri-implant bone, implant components, and microgap formation: a finite element analysis

BackgroundA new two-piece abutment design consisting of an upper prosthetic component and tissue-level base has been introduced; however, the biomechanical behavior of such a design has not been documented. This study aimed to investigate the effect of a two-piece abutment design on the stress in the implant components and surrounding bone, as well as its influence on microgap formation.MethodsTo simulate the implant models in the mandibular left first molar area, we established nine experimental groups that included three bone qualities (type II, III, and IV) and three implant–abutment designs (internal bone level, tissue level, and a two-piece design). After the screw was preloaded, the maximum occlusal (600 N) and masticatory (225 N) forces were established. Finite element analysis was performed to analyze the maximum and minimum principal stresses on the peri-implant bone; the von Mises stresses in the implants, abutments, bases, and screws, and the microgaps at the implant–abutment, implant–base, and base–abutment interfaces.ResultsFor all three loading methods, the two-piece abutment design and bone-level connection exhibited similarities in the maximum and minimum principal stresses in the peri-implant bone. The von Mises stresses in both screws and bases were greater for the two-piece design than for the other connection types. The smallest microgap was detected in the tissue-level connection; the largest was observed at the implant–base interface in the two-piece design.ConclusionsThe present study found no evidence that the abutment design exerts a significant effect on peri-implant bone stress. However, the mechanical effects associated with the base and screws should be noted when using a two-piece abutment design. The two-piece abutment design also had no advantage in eliminating the microgap.

Detection of Vital Anatomical Landmarks in Lower Posterior Premolars and First Molar Area (BuccallyPositioned)During Different Surgical Intervention Using Cone Beam Ct Scan

Background: The mental foramen (MF) is a very important structure; to avoid any trauma to mental nerve may be occur and in order to avoid that, its position, variation in anatomy and shapes should be clearly determined before any surgical procedure.
 Objective: To detect the exact position of MF and thickness of cortical plates in lower premolars and first molars among the Iraqi resident.
 Patients and Methods: For this prospective study, a total of 92 Iraqi adults patients (51 females, 41 males; age range 18-69 years). From October 2020 to February 2021, patients aged range from 25 to 65 years old.Five types of classification we used:
 Type 1, MF under the root of the lower first premolar.
 Type 2, MF between the root of mandibular first & second premolar.
 Type 3, MF below the root of the mandibular second premolar.
 Type 4, MF between the root of lower second premolar & first molar.
 Type 5, MF below the root of the lower first molar.
 Bone thickness is measured in the horizontal direction on the both side lingually and buccally.
 Results: The most common situation of the MF was below the root of lower second premolar.
 Conclusion: Significant difference can be noted in the mean of the distance between MF and root apex in both gender, also significant difference in mean of bone thickness noted between both genders on both sides.

Detection of Vital Anatomical Landmarks in Lower Posterior Premolars and First Molar Area (BuccallyPositioned)During Different Surgical Intervention Using Cone Beam Ct Scan

Background: The mental foramen (MF) is a very important structure; to avoid any trauma to mental nerve may be occur and in order to avoid that, its position, variation in anatomy and shapes should be clearly determined before any surgical procedure. Objective: To detect the exact position of MF and thickness of cortical plates in lower premolars and first molars among the Iraqi resident. Patients and Methods: For this prospective study, a total of 92 Iraqi adults patients (51 females, 41 males; age range 18-69 years). From October 2020 to February 2021, patients aged range from 25 to 65 years old.Five types of classification we used: Type 1, MF under the root of the lower first premolar. Type 2, MF between the root of mandibular first & second premolar. Type 3, MF below the root of the mandibular second premolar. Type 4, MF between the root of lower second premolar & first molar. Type 5, MF below the root of the lower first molar. Bone thickness is measured in the horizontal direction on the both side lingually and buccally. Results: The most common situation of the MF was below the root of lower second premolar. Conclusion: Significant difference can be noted in the mean of the distance between MF and root apex in both gender, also significant difference in mean of bone thickness noted between both genders on both sides.

A bird's-eye view of pathologist over diagnostic confusion of oral cavity lesions.

Oral cavity can be host to multitude of neoplastic, premalignant or non neoplastic pathological lesions. Diagnosis of lesions of oral cavity is always of interest to clinician and pathologist and rely on clinical appearance of lesions. There can be variation in diagnosis of clinical lesion with histopathology. Many oral carcinomas arise within the sites that previously had premalignant lesion. Incidence of oral cancers in population has increased among younger generations related to habits and lifestyle. These lesions during clinical presentation are misleading and create diagnostic dilemma owing to age, sex and distribution of lesions. Understanding distribution of oral mucosal lesions helps to diagnose lesions of oral cavity. Purpose of this study is to observe the variation in clinical diagnosis with histopathological diagnosis in patients with inflammatory, premalignant, benign and malignant lesions of oral cavity and oropharynx and also clinical distribution of lesions of oral cavity and oropharynx lesions by histopathology. Out of total 105 lesions, ulcer in oral cavity seen in 58 (55.23%) of patients, followed by swelling or feeling of lump in oral cavity in 36 (34.29%) of patients and foreign body sensation in 23 (21.90%) of patients with tongue as most frequent site for most of lesions of oral cavity accounting in 33 (31.43%) of cases, and less frequently lesions were seen in retro molar trigone area in 2 (1.90%) patients. Histopathological diagnosis of premalignant, non neoplastic and inflammatory lesions was made in 24 (22.85%) cases, benign tumours were diagnosed in 14 (13.33%) cases and rest of 67 (63.81%) lesions were malignant. Mucocoel were seen in five (4.76%) cases, radicular cyst was seen in one (0.95%) case of female patient and four cases of Leukoplakia with one case showing mild dysplasia. Among benign tumours 11 (10.47%) patients presented with gingivitis turned out to be squamous papillomas were seen in five (4.76%) cases, fibroma was diagnosed in four (3.80%) cases, pyogenic granuloma was diagnosed in four (3.80%) cases most commonly seen over gingiva and myoepithelioma of minor salivary gland was observed in one (0.95%) case over soft palate. Out of 67 cases of malignant lesions squamous cell carcinomas were seen in 59 (88.05%) cases followed by verrucous carcinoma in 3 (4.47%) cases, 2 (2.99%) cases were basaloid squamous cell carcinomas, mucoepidermoid carcinoma was seen in 2 (2.99%) cases and 1 (1.49%) case of adenoid cystic carcinoma was seen. Majority of squamous cell carcinomas cases in study were well differentiated in 49 (73.13%) cases followed by moderately differentiated in 16 (23.88%) cases and poorly differentiated in 2 (2.99%) cases. Malignant transformation of tonsil tissue post operatively was observed in 1 (0.95%) patients on histopathology. One (2.5%) case of myoepithelioma was seen in 60 years male over soft palate. Of all oral biopsies reported in study, increasing trend of malignancies in lower age groups of population making it an emerging threat to community and highlighting need to take effective measures to increase public awareness about risk factors and consequences of this condition. Screening programmes targeted to population over 25 years are recommended to overcome this.

Marginal bone loss between internal- and external- abutment connection type implants placed in the first molar area

Marginal bone loss between internal- and external- abutment connection type implants placed in the first molar area

A Case of Re-implantation at a Failed Site Using Alveolar Ridge Preservation with Open-healing Approach: A 5-year Follow-up

Immediate re-implantation after implant removal is ideal in terms of reduced treatment duration. However, in a case of severe peri-implantitis, it is difficult to predict three-dimensional changes after explantation. Alveolar ridge preservation (ARP) is an effective approach to avoid enormous soft and hard tissue augmentation. It can also reduce patient discomfort. A 55 year old patient had an implant with severe bone loss in the mandibular right first molar area. Implant removal and ARP with an open-healing approach were performed using xenogeneic bone graft and collagen membrane. The implant was placed four months after ARP. The 5-year follow-up revealed that the bone and implant conditions were maintained without any complications.

Long-term clinical outcomes of single short implants in the mandibular molar area

Other SectionsAbstractINTRODUCTIONMATERIALS AND METHODSRESULTSDISCUSSIONCONCLUSIONACKNOWLEDGEMENTSReferences

Customized in-vivo tissue engineering for bone grafting

Relevance. Jaw bone volume restoration during dental implantation and reconstructive oral surgery is a relevant problem in modern dentistry. In recent years, the needs of daily dental practice determined the search for new osteoplastic materials with desired properties, including cellular technologies, to stimulate bone regeneration and accelerate bone repair processes.Materials and methods. The study used third molar area gingival specimens to create tissue-engineered constructs for bone matrix colonization, subject to in vitro expansion. Octacalcium-phosphate-based materials (OCP), used as the carrier matrix, were characterized by a larger particle surface area for a more developed microrelief, a bioresorption rate, and a hydrophilic surface. The finished tissue-engineered construct, consisting of multipotent mesenchymal stromal cells colonized on the matrix, was implanted into an artificially created tibial defect in 8 Chinchilla male rabbits. Animal experiments were conducted according to ethical standards. Rabbits were sacrificed on days 8 and 12 for histological testing.Results. In the early follow-up period (8 weeks), there were areas of mature bone with incorporated osteoblasts. Besides, there were areas of primary bone with adhesion lines. Later (12 weeks), such granules fully integrated into the diaphysis cortical part. The results showed the preservation of the low-mineralized bone girdle, osteoid - a bone substance formation precursor, between the octacalcium phosphate granule and the bone.Conclusion. The results of the experimental study allow us to conclude that the customized tissue-engineered construct developed by us contributes to bone grafting.

Three-dimensional analysis of the relationship between mandibular retromolar space and positional traits of third molars in non-hyperdivergent adults

BackgroundThe anatomical position of the mandibular third molars (M3s) is located in the distal-most portions of the molar area. In some previous literature, researchers evaluated the relationship between retromolar space (RS) and different classifications of M3 in three‑dimensional (3D) cone—beam computed tomography (CBCT).MethodsTwo hundred six M3s from 103 patients were included. M3s were grouped according to four classification criteria: PG-A/B/C, PG-I/II/III, mesiodistal angle and buccolingual angle. 3D hard tissue models were reconstructed by CBCT digital imaging. RS was measured respectively by utilizing the fitting WALA ridge plane (WP) which was fitted by the least square method and the occlusal plane (OP) as reference planes. SPSS (version 26) was used to analyze the data.ResultsIn all criteria evaluated, RS decreased steadily from the crown to the root (P < 0.05), the minimum was at the root tip. From PG-A classification, PG-B classification to PG-C classification and from PG-I classification, PG-II classification to PG-III classification, RS both appeared a diminishing tendency (P < 0.05). As the degree of mesial tilt decreased, RS appeared an increasing trend (P < 0.05). RS in classification criteria of buccolingual angle had no statistical difference (P > 0.05).ConclusionsRS was associated with positional classifications of the M3. In the clinic, RS can be evaluated by watching the Pell&Gregory classification and mesial angle of M3.

Stress Distribution in Peri-implant Bone in the Replacement of Molars with One or Two Implants: A Finite Element Analysis.

In most cases, insertion of single implants with a standard diameter is used to replace a molar tooth but placing two implants with a narrow diameter seems to be a viable treatment modality to withstand functional and biomechanical forces. This study aimed to evaluate and compare stress distribution in the bone surrounding a single molar area rehabilitated by a single implant versus two implants with a narrow diameter. The study was conducted by computer-aided in vitro modeling. The initial model used a single implant, 4.8 mm wide in diameter, inserted with a 3.9-mm distance from both sides and 12.6-mm mesiodistal space. The second model used two 3.3-mm narrow-sized implants with a 3-mm distance from one another, 1.5 mm from both sides, and a 12.6-mm mesiodistal space. Following the completion of these models, a 100-N force was exerted obliquely, once in three locations and once in the mesial aspect of the implant-supported crown. Stress distribution was then measured using finite element analysis (FEA) with ANSYS Workbench software package in both models. The maximum stress in the bone around the single implant was less than that around double implants. The maximum stress of cortical bone in three-point loading was lower than mesial loading either in one (146.7 vs. 126.72 MPa) or two implants model (186.8 vs. 139.24). According to the results, because of more cortical bone contact area, the stress of surrounding bone in wide implant was decreased.

Assessment of Posterior Dentoalveolar Expansion with Invisalign in Adult Patients.

The primary aim was to evaluate dentoalveolar expansion with Invisalign clear aligners comparing linear measurements in ClinCheck vs. cone beam computed tomography (CBCT). This would enable an assessment of to what extent expansion gained from Invisalign clear aligners was due to buccal tipping and/or bodily translation of the posterior teeth. The study also evaluated the predictive value of Invisalign ClinCheck® (Align Technology, San Jose, CA, USA) to final outcomes. The orthodontic records of thirty-two (32) subjects comprised the sample to conduct this study. Linear values of the upper arch width were measured for premolars and molars at two different points (occlusal and gingival) utilized for ClinCheck® measurements and three different points for CBCT measurements before (T0 and after treatment (T1). Paired T-tests at a significance level of 0.05 were used for analyses. Expansion was found to be possible with Invisalign clear aligners. However, more expansion was measured at the cusp tips compared to gingival margins (p < 0.0001), indicating more tipping was occurring than bodily translation. ClinCheck® also showed a significant overestimation of the amount of expansion capable, with nearly 70% expression in the first premolar area, and the expression decreased as one moved posteriorly with only 35% expressed at the first molar area (p < 0.0001). Dentoalveolar expansion with Invisalign is achieved through buccal tipping of posterior teeth and bodily translation; and there is a significant overestimation of the amount of expansion achieved between ClinCheck® and clinical results.

Idiopathic Osteoesclerosis: A rare CBCT incidental finding in the mandibular condyle

Intrabony radiopaque lesions are common manifestations of neoplasia, sequel of carious lesions, traumatic event, malignant tumors, metastasis, neoplastic and non-neoplastic entities or developmental alterations. Idiopathic Osteosclerosis (IO) is a rare bone lesion, normally asymptomatic and not associated with inflammatory, traumatic or infectious stimulus which is usually found in the molar mandibular area. Although IO is a well-recognized radiological entity that is generally symptom-free, it is important to distinguish it from other radiopacities. Finding this type of lesion in the mandibular condyle is odd and it could be easily misdiagnosed and confused with other imaging findings. The present case report aims to describe a rare imaging finding of idiopathic osteosclerosis in temporomandibular condyle which was accidentally found in the CBCT of a patient with painful TMD symptoms by emphasizing the importance of multidisciplinary involvement between the general practitioner, the radiologist and the pain specialist to diagnose and provide an indicated treatment, whenever necessary.

Abutment-Bar Structure Connection Geometry: An Important Design Parameter for Implant-Supported Bar-Retained Overdentures With Cantilever Extension.

When extended distally due to higher loading in the posterior region, implant-supported bar-retained overdentures with cantilever bar extension exhibit greater bending moments on the implants closest to the cantilever bar and increased stresses in the overdenture components. In this study, a new abutment-bar structure connection was introduced to minimize undesired bending moments and reduce the resulting stresses by increasing the rotational mobility of the bar structure on the abutments. Copings of the bar structure were modified to have 2 spherical surfaces, sharing the same center, located at the centroid of the top surface of the coping screw head. The new connection design was applied to a 4 implant-supported mandibular overdenture to create a modified overdenture. Both the classical and modified models had bar structures with cantilever extensions in the first and second molar areas and were analyzed for deformation and stress distribution using finite element analysis, which was also conducted for both the overdenture models without cantilever bar extensions. Real-scale prototypes of both models with cantilever extensions were manufactured, assembled on implants embedded in polyurethane blocks, and subjected to fatigue testing. Both models' implants were subjected to pullout testing. The new connection design increased the rotational mobility of the bar structure, minimized the bending moment effects, and reduced the stress levels in the peri-implant bone and overdenture components, whether cantilevered or not. Our results verify the effects of rotational mobility of the bar structure on the abutments and validate the importance of the abutment-bar connection geometry as a design parameter.

Two-Step Progressive Transcrestal Sinus Augmentation Using a 4.5 mm Unloaded Implant as a "Temporary Implant" in Highly Atrophic Ridge: Case Report.

Severe atrophic posterior maxillary ridge (residual bone height < 3 mm) could be a challenging situation to place dental implants. Several treatment options have been proposed, but some of them may require advanced surgical skills to achieve best results. In this article, we present a novel and easier technique to allow implant placing in localized areas of severe atrophy. In a first step, a 4.5-length extra-short (unloaded) implant is placed after a transcrestal maxillary sinus floor augmentation (MSFA). After the gained apical bone consolidation, this "temporary implant" is atraumatically removed and a longer and wider definitive implant is placed to support the definitive single restoration. The case of a 45-year-old female treated with this approach is also presented. The patient suffered a severe resorption in the upper right molar area after a tooth extraction. Four months after the "temporary implant" placement and MSFA grafting with plasma rich in growth factors and autologous bone, 3 mm of dense apical bone gain could be observed. In a second surgical time, the 4.5 mm-length "temporary implant" was removed, and a 5.5 mm-length "definitive implant" was placed. This second implant was placed in a denser type 1 (1,000 Hounsfield Unit) new formed apical bone. Four months later, the implant was loaded with a screw-retained crown over a transepithelial (intermediate abutment). After 1-year follow-up, the implant was in health and no mechanical or biological complications were noticed. The satisfactory results of this case encourage the realization of new studies to elucidate its reproducibility.

General adsorption isotherm for polyoxyethylene alkyl ethers CnEOm adsorbed at the water/air surface

An empirical adsorption isotherm model is presented based on fundamental thermodynamic equations of adsorption for the homologous series of the nonionic surfactants polyoxyethylene alkyl ethers (CnEOm) at the aqueous solution surface to determine the surface tension and surface pressure isotherms, surface equation of state, and molar characteristics for the adsorbed surfactant molecules. The new model describes the surface properties of CnEOm much better than the original Langmuir adsorption model used as thermodynamic basis. The analysis of the results shows that the increase of the alkyl chain length n (hydrophobic part) leads to an increase in the adsorption activity, while the increase of hydrophilic head group given by the number of EO units m, leads to a better solubility in water, and hence, to a smaller adsorbed amount. The results also show that the ethylene oxide group mainly influences the molar surface area.

Evaluation of dental anomalies in pupils of educational institutions of the Ministry of Defense of Russia and its impact on the level of anxiety

Relevance. Distoclusion is the most common anomaly of occlusion in childhood. Genetic predisposition, bad habits, premature loss of teeth, somatic pathologies are predisposing factors for impaired growth and development of the maxillofacial region. Pupils of general educational organizations of the Russian Ministry of Defense serve as a personnel reserve for law enforcement agencies and services, and their health, including dental health, is a priority for its preservation and strengthening Intention – To assess effects of distoclusion on the child’s social and psychological adaptation.Methodology. 50 children of 11–12 years with distoclusion (К07.20 by ICD-10) who were enrolled in the 1st year of study underwent survey along with their legal representatives to identify complaints and somatic pathology, as well as an assessment of the psychological status using the Children’s Form of Manifest Anxiety Scale (CMAS); clinical examination; photo protocol; calculation of 3D control and diagnostic models by the method of Pont, Ton, Korkhaus.Results and Discussion. When being taken anamnesis, children and their parents complained of aesthetic and functional disorders. A significant correlation was found between the narrowing of the upper jaw in the area of the premolars by (5.4 ± 0.)7 mm, in the area of the molars by (5.7 ± 1.3) mm; narrowing of the lower jaw in the area of premolars by (6.0 ± 0.3) mm and molars by (4.1 ± 0.7) mm and the psychological state of the examined children. The average CMAS level was (7.3 ± 2.3), which indicates increased anxiety in the children. 8 (16 %) pupils had a high level of anxiety and required measures of psychological correction and psychoprophylaxis.Conclusion. In pupils with distoclusion, there is a pronounced narrowing of the dentition in the area of premolars and molars, significant overjet, protrusion of the anterior group of teeth, which affects the aesthetic perception by others and is reflected in the psychological state of the examined children.

Bone thickness and height of the buccal shelf area and the mandibular canal position for miniscrew insertion in patients with different vertical facial patterns, age, and sex.

The objectives of this article were the following: (1) to analyze bone thickness and height (BTH) of the buccal shelf area (BS) quantitatively in four different potentially eligible sites for miniscrew insertion; (2) to compare and contrast BTH and the changes in spatial position of the inferior alveolar nerve canal (IANC); and (3) to assess differences with age among vertical facial patterns (hypodivergent, normodivergent, and hyperdivergent) and well as by sex. Cone-beam computed tomography scans of 205 individuals (110 women and 95 men) were divided into groups according to age, vertical facial pattern, and sex. The BTH of the BS and the BTH to the IANC were measured in the mesial and distal roots of the first and second molars. BTH progressively increased in a posterior direction (P < .001), while BTH to the IANC increased and decreased (P < .001) for thickness and height, respectively, in the same direction in all age groups, for the three different vertical facial patterns, and in both sexes. Women showed significantly less BTH to the IANC (P < .002). Hypodivergent patients had greater BTH (P < .024) and a smaller bone height to the IANC (P < .018) only in the first molar region. Patients over 40 years of age had lower bone height in the second molar area (P < .003). The ideal place for BS miniscrew insertion is the region of the distal root of the second molars, regardless of facial pattern, sex, and age. The BS in women has less BTH and less BTH to the IANC.

Effect of 940 nm diode laser irradiation and dentin bonding agent on permeability of furcation area in primary molars.

Multiple accessory canals make furcation area of primary molars the most common port of entry of bacterial endotoxins to periradicular area. Reduction in permeability can improve prognosis of these teeth. Therefore, this study was designed to compare the effect of 940 nm diode laser and dentin bonding agent on the dye penetration of furcation area in primary molars. Thirty teeth were divided into three groups, that is, Group 1 (control group), Group 2 (dentin bonding agent applied over floor of pulp chamber), and Group 3 (diode laser irradiated over floor of pulp chamber). The samples were prepared and seven from each group were tested by dye penetration and three were sent for scanning electron microscopy. Rise in temperature in the perifurcal area was also recorded at the time of laser irradiation. Dunn's pair-wise comparison analysis was used for the analysis for the difference in dye penetration among the group. : The maximum rise in temperature recorded postirradiation was 6.90C. Dye penetration was significantly reduced in Group 2 Dentin bonding group (DBG) as compared to control group (P = 0.0025). Reduction in permeability was observed in Group 3 Laser group (LG) but this was not statistically significant (P = 0.197). Scanning electron microscope revealed open dentinal tubules in Group 1. There were no open dentinal tubules in Group 2, while Group 3 had sealed dentinal tubules with glass-like surface over the region. Dentin bonding agent led to substantial decrease in dye penetration of furcation area of primary molars. This method should be evaluated clinically to improve successful pulpectomy procedures of primary molars.

Influence of Platform-Switched Restoration on Bone Resorption in Patients Treated with Wide-Diameter, External-Hex-Connection Dental Implants: A 10-Year Follow-up Study.

Purpose: To investigate and assess the differences in crestal bone loss (CBL) between wide-diameter, external-hexagon-connection implants restored with platform-switching (PS) and platform-matching (PM) restorations with a follow-up of 10 years. Materials and Methods: This study retrospectively analyzed the updated and enlarged dataset of a 5-year prospective clinical study at 10-year follow-up. The data concerns 182 healthy adult subjects treated in a private dental practice who received a single wide-diameter implant with an external hexagon connection in the molar area, restored with either a PS restoration (test) or PM restoration (control). The amount of CBL was radiographically measured at each annual follow-up, as well as after 5 and 10 years of implant loading. In evaluating the association between the two types of abutments and bone loss (including change over time), a linear mixed effects model was run for longitudinal data. Results: Implants connected with PS restorations exhibited significantly lower reduction (0.25 mm) in CBL than those joined to PM restorations (P < .001; 95% CI from 0.22 to 0.29). However, both groups presented a higher increase in bone loss during the first year (0.58 mm in PS and 0.83 mm in PM) and a linear increment thereafter until the 10-year follow-up (0.046 mm/year; P < .001; 95% CI from .042 to .049). Conclusion: Notwithstanding the limitations of this study, it can be concluded that after 10 years of follow-up, the implant with a wide diameter and external-hexagon connection restored with a PS abutment seems to be more effective in reducing bone loss compared with the PM abutment.