Molar Area Research Articles

Experience summary of 11 patients undergoing autogenous tooth transplantation by using the undersized third molar as the donor tooth

AbstractAimTo explore the clinical effect of autogenous tooth transplantation with the undersized third molar as a donor tooth.Material and methodsThe general situation, donor tooth and recipient area, timing of the operation, intraoperative and post‐operative treatments and curative effect evaluation of 11 patients undergoing autogenous transplantation of the third molar were analysed retrospectively.ResultsA total of 11 patients undergoing autogenous tooth transplantation, including 4 males and 7 females, with an average age of (34.9 ± 7.5) years. Among the donor teeth, 8 were located in the maxilla and 3 in the mandible. In the recipient area, 7 affected teeth needed to be extracted because they could not be reserved, and 4 teeth had been extracted. The recipient area was located in the anterior area in 2 patients, the premolar area in 6 patients and the molar area in 3 patients. Six patients underwent simultaneous tooth extraction and autogenous tooth transplantation, 5 patients underwent two‐stage transplantation, and all patients underwent elastic fixation of the transplanted teeth. During the operation, 8 patients only underwent soft tissue preparation, 3 patients underwent soft and hard tissue preparation, and 4 patients underwent guided bone regeneration. All 11 patients underwent improved root canal treatment, of whom, 9 patients underwent crown restoration. The mean post‐operative follow‐up time was (24.82 ± 16.41) months, the success rate was 90.91% and the survival rate was 100%.ConclusionsThe third molar can be used as the donor tooth for autogenous tooth transplantation with a higher success rate.

Micro-tomographic analysis of the root trunk and pre-furcation area of the first mandibular molars.

This study analyzed the root trunk (RT) and the pre-furcation area (PFA) of mandibular first molars. Thirty lower first mandibular molars extracted due to advanced periodontal disease were evaluated in a high-energy spiral computerized micro-tomography. Two gutta-percha markings on the cementoenamel junction (CEJ) and at the furcation entrance (FE) at buccal and lingual surfaces served as reference points for measurements of RT length, and PFA width and depth, at the levels of CEJ, 1mm apical to CEJ, 2mm apical to CEJ, and at the FE. The mean RT length was 2.49mm at buccal and 3.18mm at lingual sides. The mean widths of the PFA at CEJ, at 1 and 2mm apical to CEJ, and at FE were 2.9, 3.4, 3.9 and 4.3mm, respectively, while the mean depths were 0.19, 0.32, 0.57 and 1.1mm, respectively. The PFA coincided with CEJ in 10 buccal and 10 lingual surfaces, representing 33.33% of the sample. There was a negative correlation between RT length and PFA dimensions. This study concludes that the RT length was smaller than previous studies. From the CEJ up to the furcation entrance, the PFA showed a progressive increase in width and depth. The coincidence of the PFA area beginning at the CEJ in 1/3, and the negative correlation between RT length and PFA dimensions may represent greater risk factor for the early development of furcation lesions.

Characteristics of the alveolar bone defects evaluated by cone-beam CT in periodontitis patients with orthodontic treatment history of Angle class Ⅱ malocclusion

Objective: To evaluate the levels of alveolar bone defects by using cone-beam CT in periodontitis patients with history of orthodontic treatment and to find the special tooth positions, sites and periodontitis stages of alveolar bone defects, so as to provide reference for the formulation of clinical personalized diagnosis and treatment plans. Methods: Thirty patients who were diagnosed as Angle class Ⅱ malocclusion, treated by using labial fixed orthodontic appliances and also diagnosed as periodontitis (orthodontic group) were recuited from January 2009 to June 2019 at the School and Hospital of Stomatology, China Medical University in the present study. They were aged (27.0±5.4) years old (ranged 18-41 years old). Another 60 periodontitis patients without a history of orthodontic treatment matched according to age, gender and severity of periodontitis were selected as control group (non-orthodontic group). They were aged (26.7±5.2) years old (ranged 18-41 years old). Cone-beam CT images were used to measure the heights of the alveolar bone defects at each tooth position of the patients. The difference in the heights of the alveolar bone defects between the orthodontic group and the non-orthodontic group at the same position of the maxillary and mandibular alveolar bones were compared. The specificities of the defect heights in different positions of the maxillary and mandibular alveolar bones and different sites of the same tooth position were analyzed among orthodontic group. The specificities of the different tooth positions of the maxillary and mandibular alveolar bones of the different periodontitis stages among orthodontic group were compared. Results: The heights of the alveolar bone defects in the maxillary canine area and molar area, the mandibular incisor area, the canine area and the premolar area in the orthodontic group were higher than that in the non-orthodontic group, and the differences were statistically significant (P<0.05). In orthodontic group, the most severe teeth in the maxillary and mandibular alveolar bone defects were the canine areas [(3.75±1.00), (3.83±1.10) mm]. Secondly, the more severe tooth positions of the maxillary alveolar bone height defects were the molar area [(3.67±0.84) mm] and the incisor area [(3.39±0.83) mm] and the more severe tooth positions of the mandibular alveolar bone defects were the incisor area [(3.73±1.42) mm] and the molar area [(3.54±0.81) mm]. The height of the alveolar bone defect in the mandibular incisor area was greater than that in the maxillary (P<0.05). The bone defect in the maxillary molar area was severer than that of the mandibular area (P<0.05). The alveolar bone defects in the buccal and lingual sides were mostly larger than that of the mesial and distal sides both in maxillary and mandibular positions except for the maxillary incisor area(P<0.05). The most severe alveolar bone defect position changed with the periodontitis stage. The most severe tooth position of the maxillary in stage Ⅰ periodontitis was in the molar area [(3.26±0.63) mm], whereas the incisor area was the most severe tooth of the mandible [(3.14±1.04) mm]. In addition, among maxillary incisor area, canine area, premolar area, molar area, the most severe alveolar bone defect height was the canine area in stage Ⅱ, Ⅲ, Ⅳ mandibular (P<0.05). Conclusions: In periodontitis patients with a history of orthodontic treatment, the height of the alveolar bone defect was specific to the tooth positions and sites. With the periodontitis stage changing, the most severe defect position changed in both maxillary and mandibular alveolar bones. It is recommended to pay more attention to the alteration of alveolar bone in periodontitis patients with a history of orthodontic treatment and give timely targeted treatment plans.

FEATURES OF DIAGNOSIS AND TREATMENT OF PATIENTS WITH REDUCED BITE HEIGHT

Aesthetic and hygienic requirements of patients with reduced bite height necessitate the use of modern orthopedic constructions. The main cause of this disease is pathological abrasion of the hard tissues of the teeth, the prevalence of which ranges from 4 to 57% at a young age, reaches 91% in the elderly and is accompanied by both morphological and functional disorders of the dental-maxillary system.&#x0D; The aim of the research. Research the features of the diagnosis of dental status in patients with reduced bite height and timing of their treatment.&#x0D; Materials and methods of research. Determine the degree of reduction in the height of the bite in persons with pathological abrasion of the hard tissues of the teeth of varying severity compared with the norm and features of its recovery.&#x0D; Research results and their discussion. In order to prepare for orthopedic treatment, we determined the height of the bite in 123 patients. Accordingly, they were divided into three groups. Group 1 consisted of 32 patients with included dentition defects with reduced bite height up to 2 mm (n = 32), group 2 - examined with included dentition defects with reduced bite height 2-4 mm (n = 31), group 3 are patients with included dentition defects with reduced bite height of 4-6 mm (n = 30). All persons of the main groups belonged to the second and third age groups according to the WHO, aged 35-55 years, who required orthopedic treatment with fixed constructions of dentures.&#x0D; The control group (n = 30) are young people who belonged to the 1st WHO age group (age - 18-34 years) with intact dentition, without concomitant somatic and dental pathology, were examined in one visit.&#x0D; In order to study the degree of dependence of bite height reduction between incisors, canines, premolars and molars, we studied 30 gypsum models of supergypsum of the upper and lower jaws without reduction of bite height and 93 - with varying degrees of pathological abrasion of tooth hard tissues of all examined people.&#x0D; The models were fixed in a standard articulator in the central occlusion position. Using a caliper, we determined the size of the tooth crowns and compared it with standard sizes.&#x0D; In this research, we found the dependence of the degree of reduction in the height of the bite in the area of molars - premolars - incisors and canines in the ratio 1: 1,25: 1,5.&#x0D; We performed orthopedic treatment and subsequent clinical observation for each patient for 6 months, examining their condition after fixation of prostheses in 1 week and in 1, 3 and 6 months after orthopedic treatment.&#x0D; Based on the diagnosis of bite height reduction, we provided practical recommendations on the terms of use of fixed pharmacy bridges prostheses according to the degree of bite height reduction in the examined people.&#x0D; In the case of patients with a decrease in bite height by 3-4 mm, permanent orthopedic treatment is possible in 90 days after fixation of temporary orthopedic constructions in the oral cavity, and in patients with a reduced bite height of more than 4 mm - in 180 days.&#x0D; Conclusions. According to the results of the research, a high efficiency of determining the degree of reduction in bite height in preparing patients for permanent orthopedic treatment depending on the severity of the pathological process.

Evaluation of the anti-microbial properties of prepared herbal solution on dental impressions with irreversible hydrocolloid- an ex vivo study

Aim: of this study is evaluation of the anti-microbial properties of prepared herbal solution on dental impressions with irreversible hydrocolloid. The study is an ex-vivo comparative study.Material and methods: includes Herbal ingredients: Neem, Tulsi, Reetha, Aloe vera, Neem seed oil, Ginger oil, Peppermint oil, Gum acacia, and Rock salt were used to prepare herbal disinfectant solution. Preparation of this disinfectant solution includes extract preparation by reflux method, filtration, evaporation and homogenization. Minimum inhibitory concentration of this solution was determined and in-vitro antimicrobial properties were checked with disc diffusion method. To check whether the anti-microbial property of herbal solution was useful in dentistry, 10 sectional maxillary impressions of left side were made with irreversible hydrocolloid. In the molar area each impression was cut in two halves. One half was washed with water and other half was sprayed with herbal solution. Impressions were kept for 2 to 3 minutes and then placed in inoculated agar plates. Incubation of agar plates was done for 24 hours and checked for bacterial growth. Mann Whitney ‘U’ test and Chi Square test were used to evaluate the data.Results: found that Agar plates having sectioned alginate impression sprayed with disinfectant herbal solution showed less bacterial growth compared with the agar plates having alginate washed with water. To conclude Herbal disinfectant solution is effective in controlling the bacterial growth on impressions with irreversible hydrocolloid

Pediatric dentistry sealants, do they really protect teeth from different mechanical processes?" Literature review

The use of pit and fissure sealants in the area of pediatric dentistry has been very helpful as a preventive measure to avoid carious lesions generally given in the occlusal area of the first permanent molars erupted. These sealants have had constant variations over time, however, the most used are resinous sealants. These types of sealants are mainly classified in polymerization, viscosity and translucency. As dentistry has advanced, they have been divided into two groups (hydrophobic and hydrophilic), both with different characteristics, but with the same purpose, to provide a protective barrier between extrinsic factors and the tooth. However, when in contact with different elements such as humidity, carbohydrates and saliva, as well as having a bad application on the pits and fissures, these tend to fail and begin to present diverse problems such as microfiltration, retention failures and their microhardness. The objective of this literature review was to recognize whether these sealants are adequate to protect the teeth from external factors and whether they can resist various mechanical changes. For this purpose, a literature review was carried out in various databases and dental journals, and articles were selected according to their evidence, established criteria and the year of publication, which was between 2015 and 2020.

Stress Distribution and Displacement of Craniofacial Structures Following Rapid Maxillary Expansion in Different Types of Cleft Palate: A Three-Dimensional FEM Study.

To evaluate displacements and stress distributions in finite element models (FEMs) of the craniofacial complex of 13-yearold male patient with complete unilateral cleft palate (UCP), a 15-year-old female patient with complete bilateral cleft palate (BCP), and a 15-year-old female patient with isolated cleft palate (ICP), which may respond differently to expansive forces. The FEMs were based on computed tomography scans of patients with UCP, BCP, and ICP who needed maxillary expansion. Von Mises stress distribution after 0.2 mm of expansion and displacements after 5 mm of expansion were investigated. The highest amount of stress was observed in the ICP model. Surprisingly, no stress was noted around the nose in the BCP model. The amount of dentoalveolar expansion decreased from anterior to posterior on the cleft side of the UCP, BCP, and ICP models. In contrast, on the non-cleft side of the UCP model, the maximum dentoalveolar expansion occurred at the molar area, decreasing toward the anterior parts. Anatomical structures expressed posterior displacement in the UCP model. In the ICP model, structures close to midline showed anterior displacement, while structures in the lateral parts showed posterior displacement. In contrast with the other 2 models, the structures in the BCP model showed anterior displacement. Vertically, all the anatomic structures in the BCP model showed inferior displacement, while in the ICP and UCP models, only the structures close to the midline showed inferior displacement. Maxillary expansion caused different patterns of stress distribution and displacement in different types of clefts. Clinicians should consider the type of the cleft, and may expect differing patterns of widening following maxillary expansion.

Multiple Odontogenic Keratocysts in a Non-syndromic Young Patient: An Unusual Case Report

Odontogenic keratocyst (OKC) is a benign intraosseous lesion with invasive and aggressive behavior. It comprises approximately 2-21.8% of all jaw cysts. Odontogenic keratocysts (OKCs) are believed to arise from remnants of the dental lamina most common site in the molar ramus area. OKCs have a specific histopathologic appearance and are found to be locally aggressive and have a high recurrence rate, thus requires close long-term follow-up. OKCs are one component of the Gorlin-Goltz syndrome and all patients with multiple OKCs should be evaluated for this syndrome. In this paper, we present a case of a 13-year old non-syndromic female patient with multiple OKCs located at symphysis and bilateral mandibular angle region who was treated surgically with no obvious post-operative complications during follow-up period.

Effect of specific retention biomaterials for ball attachment on the biomechanical response of single implant-supported overdenture: A finite element analysis

The purpose of this finite element analysis (FEA) was to evaluate the effect of specific retention biomaterials with different elastic modulus on the biomechanical response to the axial and off-axial biting loads of a mandibular midline single implant-supported overdenture (SIO) model. Five 3-dimensional (3D) finite element models of an edentulous mandible with SIO were designed as follows: model M with a titanium retentive element for ball attachment, model P with a PEEK retentive element, model S with a silicone resilient liner retentive element, model T with a thermoplastic acrylic resin retentive element made from a CAD-CAM material, and model A with a polyacetal resin retentive element. Posterior bilateral vertical load (PV) at the 1st molar areas and anterior oblique load (AO) at the incisal edge of the mandibular central incisors at a 30-degree angle of 100N were applied. Stress values were recorded. Stress values were higher for all models under (AO) loading than under (PV) loading. Model M recorded the highest stress values on the implant, its components, cortical, and cancellous bone under both loading conditions. Under (AO) loading condition, the ball abutment von Mises stress value in model S was almost 7 times lower than that of model M (19 and 130MPa respectively) and the other 3 models (P, T, and A) (119, 121, and 120MPa respectively). However, model S recorded the highest value of denture base stress at the attachment area. The elastic modulus of retention materials can affect stresses generated on the implant overdenture components and supporting structures.

Correlation of Three Dimensions of Palate with Maxillary Arch Form and Perimeter as Predictive Measures for Orthodontic and Orthognathic Surgery.

Hard palate is regarded as an important part of the human skull, which contributes to the separation of the oral and nasal cavities. The aims of the study were to investigate the morphology of the hard palate in order to create a general guideline of three-dimensional values of the palate in a Kurdish sample in the city of Sulaimani as well as determining the possible correlations between different palatal parameters in class I malocclusion with the maxillary arch form and perimeter. A retrospective study design was adopted by collecting 100 study models of orthodontic patients aged 16–24 years old attending different private dental clinics in the city of Sulaimani seeking orthodontic management. In this study, three-dimensional palatal measurements including depth, length, and width were measured in an attempt to discover their correlation with each maxillary arch form and perimeter. Additionally, measurements of inter-molar width, inter-canine width, and arch perimeter were carried out. About two-thirds of those seeking orthodontic treatment were females. Nearly 80% of the study sample had narrow palate followed by 15 and 5% of intermediate palate and broad palate, respectively. In regard to arch form, almost 90% of subjects were with tapered maxillary arch form and 10% of them with oval arch form. Males had increased dimensions compared to females, with significant differences, except in palatal depth in the molar area, and palatine height index, in which females showed increased dimensions than males but the differences were statistically non-significant. A strong positive correlation was observed between arch form and canine depth. In regard to arch perimeter, a strong negative correlation was found with molar depth and a medium positive correlation with each of canine depth, palatal width, and palatal length.

Biomechanical Evaluation of Different Implant-Abutment Connections, Retention Systems, and Restorative Materials in the Implant-Supported Single Crowns Using 3D Finite Element Analysis.

This is an in silico study aimed to evaluate the biomechanical influence of different implant-abutment interfaces (external hexagon and Morse taper implants), retention systems (cement and screw retained), and restorative crowns (metal-ceramic and monolithic) using 3-dimensional finite element analysis (3D-FEA). Eight 3D models were simulated for the maxillary first molar area using InVesalius, Rhinoceros, and SolidWorks and processed using Femap and NEi Nastran software. Axial and oblique forces of 200 and 100 N, respectively, were applied on the occlusal surface of the prostheses. Microstrain and von Mises stress maps were used to evaluate the deformation (cortical bone tissue) and stress (implants/fixation screws/crowns), respectively, for each model. For both loadings, Morse taper implants had lower microstrain values than the external hexagon implants. The retention system did not affect microstrain on the cortical bone tissue under both loadings. However, the cemented prosthesis displayed higher stress with the fixation screw than the external hexagon implants. No difference was observed between the metal-ceramic and zirconia monolithic crowns in terms of microstrain and stress distribution on the cortical bone, implants, or components. Morse taper implants can be considered as a good alternative for dental implant rehabilitation because they demonstrated better biomechanical behavior for the bone and fixation screw as compared to external hexagon implants. Cement-retained prosthesis increased the stress on the fixation screw of the external hexagon implants, thereby increasing the risk of screw loosening/fracture in the posterior maxillary area. The use of metal-ceramic or monolithic crowns did not affect the biomechanical behavior of the evaluated structures.

Experience in the use of high-molecular-weight hyaluronic acid in the treatment of chronic generalized periodontitis

As a rule, periodontal diseases are accompanied by marginal recession of the gums, loss of attachment and exposure of the roots of the teeth. Traditional drugs for injection treatment are being replaced by modern drugs based on high molecular weight hyaluronic acid, which are successfully and highly efficiently used for local therapy of inflammatory and destructive periodontal diseases. In order to restore the volume of soft tissues in the interdental spaces, eliminate recessions and bleeding of the gingival margin, a preparation of high molecular weight hyaluronic acid “Revident +” was used, which was injected into the base of the gingival papilla at a distance of 2—3 mm from its top with the bevel of the needle upwards. To assess gingival bleeding, the PBI (papilla bleeding index) index was used, which is a sensitive indicator of the severity of gingival inflammation. The magnitude of gingival recession before and after treatment was assessed according to its severity: mild — up to 3 mm, moderate — 3—5 mm, and severe — 6 and more mm. Examination of periodontal patients before and 1.5 months after the application of high molecular weight hyaluronic acid in the composition of the Revident + preparation showed that the degree of gingival bleeding according to PBI decreased significantly after the third visit from 4 to 2 and from 3 to 1, respectively. The degree of gingival recession in the area of the anterior group of teeth decreased by an average of 2.1 mm, in the area of premolars — by 2.5 mm, and in the area of molars — by 2.8 mm.

Treatment of Serious Occlusal Instability Associated with Temporomandibular Disorders (TMDs) Through Implant and Dynamic Occlusal Schemes Rehabilitation. A Case Report

A case report of 35 years old male patient, partially edentulous with occlusal instability, Disc Displacement with Reduction (DDWR), Local Muscle Soreness (LMS) and Alteration of vertical dimension is presented. Rehabilitation was planned to achieve predictability of long-term treatment, providing static and dynamic occlusal stability. A therapeutic occlus ion with premature contact in the right premolar sector was planned. Implants and cemented/screwed crowns were used to obtain contacts in the molar area. The restoration of dynamic occlusal schemes was made by direct adhesive technique in the anterior sector and Curve of Spee (COS) compensation with temporary anchoring for molar inclusion was used. Patient presents objective and subjective improvements associated with the treatment performed. Temporomandibular disorder is stabilized and controlled by a specialist.

Effects of Palatal Expansion with Torque Activation using a Transpalatal Arch: A Preliminary Single-Blind Randomized Clinical Trial.

Purpose The literature regarding the treatment of posterior crossbites using a transpalatal arch (TPA) is scarce. Moreover, there is only one clinical study on the correction of unilateral crossbites using torque activation. This is an important clinical issue; therefore, this study was conducted to show the effects of an active Goshgarian TPA in correcting nonfunctional single-tooth unilateral crossbite. Methods The present single-blind, randomized clinical trial examined 60 observations on 30 individuals with nonfunctional single-tooth unilateral crossbites in the first permanent molar area. Patients were randomly divided into two groups of “symmetric expansion” [control] and “expansion + torque activation” using Goshgarian TPAs [experimental]. The palatal arch was expanded at a rate of 2 mm/month, for 2–8 months. The average treatment durations were 157.9 and 117.1 days, respectively, for the control and experimental groups. Dentoskeletal alterations were assessed on dental records, posteroanterior frontal cephalographs, and occlusal radiographs taken before and after treatment. Changes induced by treatments in each group and differences between changes in both groups were analyzed statistically (α = 0.05). Results The treatment duration was significantly shorter in the experimental group (P < 0.05). The extent of dental displacement on the crossbite side was significant no matter what treatment was applied (P < 0.001); no between-group difference was detected (P > 0.05). Both treatments tilted the teeth in crossbite (P < 0.001) without any between-group difference (P > 0.05). The noncrossbite molar was displaced in the control group, whereas this did not occur in the experimental group (between-group P < 0.001). Conclusions The Goshgarian TPA can be used with torque activation in order to deliver a more effective and faster correction of nonfunctional single-tooth unilateral crossbites with more favorable clinical results.

A strategy for characterizing the surface layer at the liquid-vapor interface of binary liquid mixtures containing non-ionic surfactants: An approach from Gibbs adsorption isotherm

In this work, an alternative physicochemical procedure is presented to characterize the liquid-vapor interface of binary liquid mixtures containing non-ionic surfactants, using the Gibbs adsorption isotherm, the solute activity, and the surface partial molar areas. This model allowed to calculate the moles of solute and solvent present in equilibrium for both bulk and surface phase. The excess surface concentration, relative surface concentration, and molar fraction of both components was also calculated. The results reflected that the excess surface concentration of the solute was not proportional to the adsorption of the solute with the increase in its concentration in the bulky phase. This gives evidence that the dilute solutions were able to saturate the surface layer at an early stage and after it, for the entire concentration range where it remains approximately constant, which showed the existence of a compact molecular arrangement.

A Case Report of Juvenile Intraoral Pleomorphic Adenoma

Pleomorphic adenoma (PA) is the most common tumour of the salivary glands. About 90% of these tumours occur in the parotid gland and ten % in the minor salivary glands. The most common sites of Pleomorphic adenoma of the minor salivary glands are the palate, followed by lips and cheeks. Throat, floor of the mouth, tongue, tonsil, pharynx, retro molar area and nasal cavity are rarely involved. Pleomorphic adenoma typically present as a slow growing, unilateral and painless mass of salivary glands, with a predilection for recurrence and risk of malignant transformation (about 1.5% up to five years and increases to 9.5% after more than 15 years). This case report describes a case of Pleomorphic adenoma of buccal mucosa in a 13-year-old male patient.

Cone-beam Computed Tomography-based three-dimensional cephalometric analysis of mandible symmetry and the occlusal plane of adult patients with high-angle skeletal class III malocclusion and jaw deformity

ObjectiveTo use cone beam computed tomography (CBCT) scans to analyze mandibular symmetry, the occlusal plane and their correlations in patients with high-angle skeletal class III malocclusion and jaw deformity. DesignReconstructed images simulated of CBCT data of 20 adult patients with high-angle skeletal class III malocclusion and jaw asymmetry (Experimental group) and 20 adult patients of skeletal class I with normal faces (Control group) were measured with a three-dimensional (3D) geometric morphological measurement system. Related landmarks, lines and planes were marked and relevant distances and angles of 3D craniofacial structures were measured. The Student t-test was performed to assess symmetry. With the help of the Pearson correlation and Linear regression, we explored the correlations and other relationships among them. ResultsCompared with control group, the symmetrical differences in experimental group were concentrated in condyle, coracoid process, mandibular angle, mandibular first molar area and the chin (P < 0.05). A strong positive correlation was found between the degree of mandibular deviation and the inclination of the occlusal plane in the coronal position (r = 0.860, P < 0.001) and a linear relationship between them was found: Y = 1.300 + 0.419X (the inclination of occlusal plane was Y, and the mandibular deviation was X). ConclusionsCertain characteristics of mandibular symmetry and the occlusal plane were found in patients with high-angle skeletal class III malocclusion and jaw asymmetry. These findings provide references for doctors to pay attention to the degree and location of mandibular asymmetry and to determine the occlusal plane.

Factors Influencing the Accuracy of Freehand Implant Placement: A Prospective Clinical Study.

(1) Background: The objective of implant prosthetic restoration is to ensure the best possible rehabilitation of function and esthetics. Optimal positioning of the implant with regard to the bone availability, surrounding soft tissue, and prosthetic sustainability should be strived for during implant placement. The factors influencing freehand implant placement and the accuracy achieved with this procedure are investigated in this prospective clinical study. (2) Methods: Implants were placed in the single-tooth edentulous sites of the premolar and molar areas in 52 patients. Three-dimensional (3D)-planning was performed virtually prior to the freehand implant operation, and the desired position of the implant was provided to the surgeon. (3) Results: The deviations between the planned and the actually achieved position with freehand implant placement showed the following mean values and standard deviations: angle 8.7 ± 4.8°, 3D deviation at the implant shoulder 1.62 ± 0.87 mm, mesiodistal deviation 0.87 ± 0.75 mm, buccolingual deviation 0.70 ± 0.66 mm, and apiocoronal deviation 0.95 ± 0.61 mm. The type of jaw had a significant influence on accuracy. Major deviations were observed in the lower jaw. Furthermore, the timing of implant placement influenced the mesiodistal deviation and angular deviation; (4) Conclusions: Freehand implant placement demonstrated a higher level of deviation between the planned and actually achieved implant positions. In particular, the ranges showed a large spread. From a prosthetic point of view, there may be complications during the restoration of the prosthetic crown if the implant exit point is not optimally located or if the implants show a high angular deviation.

Pattern of Impacted Mandibular Third Molar Teeth in Rangpur Region, Bangladesh: A Radiological Evaluation

Background: Third molar is the most commonly impacted tooth in the oral cavity and accounts for large of all impactions. The most common complication in the extraction of the third mandibular molars is nerve and vessels damage. Therefore, thorough radiographic assessment is a necessary to avoid these surgical complications.&#x0D; Objective: The purpose of this study was to evaluate the frequency, angulation, depth of the impacted mandibular third molars and its relationship with ramus on radiographs.&#x0D; Materials and Methods: This study comprised 800 orthopantomograms (OPGs) of patients attending different dental clinics and hospitals in Rangpur region, Bangladesh between June 2014 to May 2015. Panoromic Radiographic assessment was carried out to evaluate the pattern of third molar impaction in terms of age, gender, angulation of impaction, level of eruption and available retromolar space using panoramic radiographs and Pell &amp; Gregory classification.&#x0D; Results: A total of 314 radiographic third molar areas were found in this study, out of them 137 belong to male patients and 177 belong to the female patients. The mesio angular types of angulation was most prevalent (46%) whereas distoangular was rare (5%) in our study. In relation to anterior border of the ramus of mandible Level B 52% and Class II 59% were the most common pattern of impaction. The female tends to be dominant as compared to male &amp; the maximum number (35%) of impacted third molars are found in an age group of 38 years and above.&#x0D; Conclusion: Panoramic radiographs can be used as reliable investigation for evaluation of impacted mandibular third molar.&#x0D; KYAMC Journal.2021;12(01): 08-13

Gambaran idiopathic osteosclerosis gigi molar ketiga impaksi pada radiograf Cone Beam Computed Tomography

Objectives: To analyze idiopathic osteosclerosis radiographs associated with impacted third molars (M3) on cone beam computed tomography (CBCT).&#x0D; Case Report: A 36-year-old woman came to the Dentology Clinic complaining that the right mandibular third molar area often felt sore. The patient was referred for CBCT examination and incidentally, a radiopaque image with clear boundaries, irregular shape was found on the periapical impacted third molar without caries in the tooth crown. The treatment plan that will be carried out on the tooth is extraction.&#x0D; Conclusion: Idiopathic osteosclerosis lesions are lesions that occur in vital teeth that have the characteristics of a well-defined radiopaque appearance and are asymptomatic. Characteristics of idiopathic osteosclerosis lesions can be visualized by CBCT well. CBCT has the advantage of being able to display a detailed picture of the lesion in three dimensions (3D) with a fairly good image resolution.