Bicuspid

BACKGROUND Fibre reinforced composite bars (FRC) have applications as bonded retainers, space maintainers and anchorage/movement units. However, the bond strength of attachments to FRC anchorage bars is unknown. AIMS To compare the shear bond strengths of brackets bonded immediately to FRCs with different orthodontic adhesive systems and bonded with the same adhesives after a 48-hour delay, abraded with a diamond bur and etched with phosphoric acid. METHOD One hundred and five recently extracted upper premolars were randomly assigned to seven groups (N = 15 teeth per group). FRCs were bonded to the buccal surfaces of the teeth and stainless steel orthodontic brackets were bonded to the FRCs with the following adhesive systems: Group 0 (Tetric Flow); Groups 1, 2 and 3 (Immediate bonding with chemically cured, no-mix and light cured composites, respectively, the bars covered with Tetric Flow); Groups 4, 5 and 6 (Bonding to FRCs delayed 48 hours, then bonded with chemically cured, no-m...

The aim of this study is to compare in vitro the fracture resistance of the endodontically treated tooth restored with a novel design Sharonlay, with the two component restorative method, i.e., post with separate onlay, and onlay without post. 45 single-rooted mandibular second premolars were taken, and root canal treatment was performed. Teeth were then randomly divided into three groups (n = 15) based on the type of restoration given: Group I - metal onlay with cast post extension (Sharonlay), Group II - metal onlay with prefabricated metal post (Mani post system), Group III - metal onlay over endodontically treated tooth obturated with Gutta-percha (control group). Fracture resistance was checked using the Instron universal testing machine and the fracture patterns were analyzed. According to the values recorded, Group I showed maximum mean fracture resistance followed by Groups II and III. Statistically significant difference was found between Groups I and II and Groups I and II...

This study aimed to establish a safety zone for the placement of mini-implants in the buccal surface between the second maxillary premolar (PM2) and first maxillary molar (M1) of Mongoloids. Thirty-two digital orthopantomograms of Mongoloids were selected and the interdental distance between the second premolar and first molar at 2, 5, 8 and 11 mm from the cemento-enamel junction (CEJ) was measured. The distance between the PM2 and M1 root apices and from the apices to the maxillary sinus was also determined. The average width (mm) at 2 mm was 2.58 +/- 0.53; 5 mm was 3.47 +/- 0.61; 8 mm was 4.00 +/- 0.74, 11 mm was 4.36 +/- 0.71 and the distance between the apices was 7.49 +/- 0.79. Only half of the samples were measured at 11 mm, as many of the root apices were superimposed over the maxillary sinus. The measurement (mm) from PM2 root apex to the sinus was -0.18 +/- 1.56, from the mesiobuccal root apex of M1 (MB1) to the sinus was -1.94 +/- 1.70 and from the midpoint between their a...

In cases of disrupted apical constriction effort is made to create an apical stop and subsequently instrument and obturate the canal up to this point. The aim of this study was to in vitro evaluate the sealing ability of three root canal sealers used with the lateral compaction technique ...

In order to evaluate the uptake of fluoride (F) into tooth structures following water fluoridation in Ho Chi Minh City, F concentrations were measured from the enamel surface through the enamel–dentine junction (EDJ) to dentine close to the pulp in premolars. Calcification ...

Paresthesia of the lower lip is uncommon during orthodontic treatment. In the present case, paresthesia occurred during orthodontic leveling of an extruded mandibular left second molar. It was decided to remove this tooth from the appliance and allow it to relapse. A reanatomization was then performed by grinding. The causes and treatment options of this rare disorder are reviewed and discussed. The main cause of paresthesia during orthodontic treatment may be associated with contact between the dental roots and inferior alveolar nerve, which may be well observed on tomography scans. Treatment usually involves tooth movement in the opposite direction of the cause of the disorder.

The aims of this report are to present three cases of autotransplantation along with a review of the indications, selection criteria for patient donor and recipient sites, and the major steps in the surgical procedure. Autogenous tooth transplantation, or autotransplantation, is the surgical movement of a tooth from one location in the mouth to another in the same individual. It can be a good treatment option in many cases if the dentist knows the implications, indications, and contraindications. Three cases with different treatment indications and plans are presented. All showed autotransplantation of teeth as part of orthodontic treatment. It emphasized the benefits of this treatment modality such as new bone formation and lower costs. One case, a rare example of multiple congenitally missing teeth treated by autotransplantation, also was presented. As shown in these case reports, there are instances where the autotransplantation of teeth is appropriate and may possibly simplify f...

The aim of the study was to assess the occurrence of some putative periodonto-pathogens in "test" and "control" sites in "diseased" and "non-diseased" persons, respectively, from an adult rural Kenyan population exhibiting poor oral hygiene and widespread loss of attachment (LA). 14 persons (less than 35 years) were assigned to a "diseased" category on the basis of at least 4 sites with LA greater than or equal to 4 mm; at least 5 mm LA and a pocket greater than or equal to 4 mm interproximally in a lower incisor ("test" site): and less than 2 mm LA and no pocket greater than or equal to 4 mm distal to a lower canine or mesial to a lower first premolar ("control" site). Age-matched "non-diseased" persons were identified on the basis of no sites with LA greater than 2 mm and no pockets greater than or equal to 4 mm associated with LA. Paperpoint samples from test and control sites as well as a scraping sample from the dorsum of tongue were examined for presence of Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Bacteroides intermedius, B. melaninogenicus group, Capnocytophaga, Selenomonas spp., and Wolinella recta. P. gingivalis was found in 79% of test sites and 36% of control sites in "diseased" persons, and in 18% and 35% of test and control sites, respectively, in "non-diseased" persons. "No other bacterial group discriminated significantly between test and control sites or between diseased and non-diseased subjects. The surprisingly high occurrence of P. gingivalis in non-diseased subjects, both subgingivally and on tongue, indicates that deep periodontal pockets are not prerequisite ecological environments for P. gingivalis establishment.

AIM This paper reported a rare case of hyperdontia in a child of 10 years who revealed a mixed dentition and a light mental retardation. MATERIALS AND METHODS The therapeutic approach has been based on interdisciplinary cooperation between the pediatric dentist, orthodontist and oral surgeon. TC-Dentascan, with a panoramic and occlusal radiographs revealed the presence of two supernumerary teeth in the premaxillary region and clinical examination showed an abnormality of dentoalveolar complex. Both impacted supernumerary teeth were extracted under general anesthesia. Clinical examination revealed that they appeared two premolars in shape with fully formed crowns and partly formed roots. RESULTS Three months after the extraction of supernumerary teeth there was a spontaneous eruption of permanent central incisors and left lateral incisor. CONCLUSION The authors emphasized the importance of removal of supernumerary teeth to eliminate the cause of a delayed eruption of permanent teeth.

The aim of this report is to describe the management of a 16-year-old patient with oligodontia including six permanent teeth. Oligodontia is agenesis of six teeth or more, excluding third molars. The etiology of congenital absence of teeth is believed to be involved in heredity or developmental anomalies. It can be isolated or as part of a syndrome. There are a number of options available to restore space generated by missing teeth. Dental treatment can vary depending on the severity of the disease and generally requires a multidisciplinary approach. Treatment options include orthodontic therapy, implants, adhesive techniques, and removable prostheses. A 16-year-old male patient with oligodontia affecting six permanent teeth received conservative care that met his and his parent's expectations. The existing primary teeth were restored to resemble permanent teeth in order to achieve a favorable esthetic result using direct composite resin. The restorative treatment was provided f...

The objective of this clinical study was to evaluate the clinical performance of implant-supported zirconia crowns with a sintered veneering cap. Furthermore, the influence of the type of retention (screw-retained vs cemented single crowns) was analysed. Fifty-eight patients were accommodated with 114 implants, inserted in the molar and premolar regions. Zirconia-based crowns with a sintered veneering cap were either screw-retained (n = 53) or cemented (n = 61) on the implant. Recalls were performed every 6 months. The state of soft tissue was documented by the modified plaque and gingiva index (mPI) and sulcus bleeding index (mSBI). The restorations were evaluated for technical failures like veneering porcelain fractures, surface qualities and marginal fitting. Neither implant loss nor crown fractures occurred. After a mean clinical service time of 36.9 months, fractures of the veneering porcelain were registered in 1.8 % of the cases. The Kaplan-Meier survival probability regardin...

The identification of specific patterns of dental anomalies would allow testing the hypothesis that certain genetic and environmental factors contribute to distinct dental anomaly subphenotypes. A sexual dimorphism in tooth agenesis and its association with other dental anomalies has been suggested. The aim of this study was to investigate a large group of children to define dental anomaly subphenotypes that

The aim of this study was to assess the clinical performance of two adhesive restorative systems (Single Bond/Filtek P-60 and Single Bond/Filtek Z-250) in posterior teeth using a modified United States Public Health Service (USPHS) system. A total of 70 restorations were placed in molars and premolars in 30 patients (14 females and 16 males; 18-40 years) by one operator. All restorations were directly evaluated by two examiners at baseline, six months, and 12 months using the following modified USPHS rating criteria: marginal integrity, marginal discoloration, surface texture, contour, postoperative sensitivity, and recurrent caries. At six and 12 months all restorations were available for evaluation of marginal discoloration, surface texture, contour, postoperative sensitivity, and recurrent caries that remained with 100% Alpha-ratings at recalls for both restorative systems. Marginal integrity for P-60 was scored as 94.3% and 91.4% Alpha at six and 12 months, respectively, and rat...

BACKGROUND Contrary to the situation for amalgam restorations, obtaining acceptable proximal contacts with posterior composite restorations can be difficult. Proximal contacts that are less than ideal may permit food impaction and subsequent caries formation and periodontal problems. PURPOSE The aim of this study was to assess the quality of proximal contacts of posterior composite restorations placed with 4 restorative techniques. METHODS Seventy-five mounted ivorine teeth with large, standardized MOD cavities were divided into 5 groups of 15 teeth each. The teeth in 4 of these groups were restored with a resin composite and those in the remaining group were restored with amalgam. The restorative techniques for the 4 composite groups were traditional wedge and matrix (Group 1), use of a light-tip attachment (Group 2), use of the Contact Pro hand instrument (Group 3) and use of Beta Quartz glass-ceramic inserts (Group 4). All restorations were completed under simulated clinical cond...

Conservative instrumentation of initial posterior approximal caries is beneficial to patients and simplifies surgical management. This article describes a minimally invasive technique for preparing Class II lesions while keeping the marginal ridge and occlusal surface intact. Eradication of caries by minimally invasive techniques and restoration of tooth form after such cavity preparation necessitates specialized restorative materials that feature adhesion to tooth structure and ion exchange to facilitate remineralization. This article outlines a conservative instrumentation sequence, followed by use of a highly viscous, rapid-setting, capsulated glass ionomer cement, for the restoration of initial posterior approximal lesions.

Talon cusp is a rare dental anomaly manifested as an accessory cusplike structure on the tooth crown. This article reports four cases of talon cusp that caused clinical problems related to appearance, occlusal interference, tooth displacement, caries, and tongue irritation. The cases presented were associated with other dental abnormalities, suggesting per se that genetic inheritance may be the causative factor. Clinical and radiographic characteristics of this developmental anomaly and modes of treatment are described.

Aim To present a unique case of mandibular first and second premolars with two roots and two root canals with the aid of spiral computed tomography (SCT). Background Confirmation of morphology of mandibular first and second premolars with the aid of SCT. Case description Mandibular premolars usually have a single root and a single canal. The occurrence of two roots with two separate root canals is extremely rare. The use of SCT in this rare case greatly contributed toward making a confirmatory diagnosis and successful endodontic management. Conclusion Successful nonsurgical endodontic management of mandibular first and second premolars with two separate roots and root canals has been presented. In this case, exact root canal anatomy could not be confirmed by using radiographs alone. Hence, the use of SCT helped us in making a confirmatory diagnosis. Clinical significance Developmental anomalies can occur in any tooth and two rooted premolars are no exception. The complexity of such ...

The aim of this study was to determine the relationship between the amount of calcium loss, lesion depth, and the accuracy of storage phosphor plate (SPP) and film radiographs for the detection of artificial proximal demineralization. Standard enamel windows of extracted premolars were exposed to a demineralizing solution for 60 h, 80 h, 100 h and 120 h. Solutions were analysed for calcium concentration by atomic absorption spectrometer and the lesion depths were calculated by a specific formula. All teeth were radiographed with SPPs and F-speed films before and after acid application. Images were evaluated by five observers. Stereomicroscopic and scanning electron microscopic (SEM) observations were carried out to visualize enamel surfaces after acid exposure. Receiver operating characteristic analysis was used for diagnostic accuracy (A(z)). A(z)s were compared with factorial analysis of variance and t-tests. The relationship between A(z)s and lesion depths was determined with Pearson's correlation test. Strong positive correlation was found between A(z)s of both radiographic methods and lesion depths. No difference was found between the A(z)s of two radiographic systems for any of the demineralization durations (p > 0.05). Pair-wise comparisons revealed no significant difference in A(z)s of SPPs (p > 0.05), while significant differences were obtained for the A(z)s of films for different demineralization periods (p < 0.05). Stereomicroscopic and SEM observations confirmed demineralizations from superficial to deeper layers of enamel. Subsurface enamel demineralization was not accurately detectable with either storage phosphor plates or F-speed films. The amount of calcium loss and the depth of demineralization have a strong relationship with diagnostic accuracy with a significant effect particularly on F-speed films.

The aim of this study was to investigate the stress distribution in a 3-D model of two-rooted tooth (first maxillary premolar) under two different occlusal force vectors by using finite element analysis. In the first model overall force of 200 N was divided into three vectors (cusp to fossa occlusion), and in the second model overall force was divided into 4 vectors (cusp to fossa and cusp to marginal ridge occlusion). The greatest compressive stress was found at the dentino- enamel junction in the cervical area of the both models (about -200 MPa). The greatest tensile stress was found at the vestibular aspect of buccal cusp in second model (about +3 MPa) and in the central fossa of the both models (about +28 MPa). Results indicate that in the both types of occlusal loadings the stress distribution was mainly compression and compressive forces were predominant over tensile stresses. In the second model with 4 vectors, stresses generated in the tooth structure were higher compared to...

This study aimed to establish a safety zone for the placement of mini-implants in the buccal surface between the second maxillary premolar (PM2) and first maxillary molar (M1) of Mongoloids. Thirty-two digital orthopantomograms of Mongoloids were selected and the interdental distance between the second premolar and first molar at 2, 5, 8 and 11 mm from the cemento-enamel junction (CEJ) was measured. The distance between the PM2 and M1 root apices and from the apices to the maxillary sinus was also determined. The average width (mm) at 2 mm was 2.58 +/- 0.53; 5 mm was 3.47 +/- 0.61; 8 mm was 4.00 +/- 0.74, 11 mm was 4.36 +/- 0.71 and the distance between the apices was 7.49 +/- 0.79. Only half of the samples were measured at 11 mm, as many of the root apices were superimposed over the maxillary sinus. The measurement (mm) from PM2 root apex to the sinus was -0.18 +/- 1.56, from the mesiobuccal root apex of M1 (MB1) to the sinus was -1.94 +/- 1.70 and from the midpoint between their a...

Two case reports demonstrate a new orthodontic method that offers short treatment times and the ability to simultaneously reshape and increase the buccolingual thickness of the supporting alveolar bone. A 24-year-old man with a Class I severely crowded malocclusion and an overly constricted maxilla with concomitant posterior crossbites and a 17-year-old female with a Class I moderately to severely crowded malocclusion requested shortened orthodontic treatment times. This new surgery technique included buccal and lingual full-thickness flaps, selective partial decortication of the cortical plates, concomitant bone grafting/augmentation, and primary flap closure. Following the surgery, orthodontic adjustments were made approximately every 2 weeks. From bracketing to debracketing, both cases were completed in approximately 6 months and 2 weeks. Posttreatment evaluation of both patients revealed good results. At approximately 15 months following surgery in one patient, a full-thickness ...

This paper reported a rare case of hyperdontia in a child of 10 years who revealed a mixed dentition and a light mental retardation. The therapeutic approach has been based on interdisciplinary cooperation between the pediatric dentist, orthodontist and oral surgeon. TC-Dentascan, with a panoramic and occlusal radiographs revealed the presence of two supernumerary teeth in the premaxillary region and clinical examination showed an abnormality of dentoalveolar complex. Both impacted supernumerary teeth were extracted under general anesthesia. Clinical examination revealed that they appeared two premolars in shape with fully formed crowns and partly formed roots. Three months after the extraction of supernumerary teeth there was a spontaneous eruption of permanent central incisors and left lateral incisor. The authors emphasized the importance of removal of supernumerary teeth to eliminate the cause of a delayed eruption of permanent teeth.

This study aimed to assess whether non-extraction, two-premolars and four-premolars extraction Class II treatment protocols are different regarding long-term facial aesthetics, age appearance, and soft-tissue measures. Frontal and lateral photographs of 63 full Class II division 1 patients, treated at least 8 years before, were evaluated by 83 laypeople and 76 orthodontists, who assigned to each one's attractiveness scores from 1 to 10, and opined about their apparent ages. Patients were divided in three groups: XP0 (non-extraction, n = 20; 30.77 years, 15.63 years post-treatment), XP2 (two-premolars extractions, n = 25; 30.99 years, 15.68 years post-treatment), and XP4 (four-premolar extractions, n = 18; 32.80 years, 18.01 years post-treatment), that were matched by gender, post-treatment occlusal and soft-tissue outcomes, age, and post-treatment time. Soft-tissue measures were obtained with Dolphin Imaging 11.5 software. Two-way analysis of variance revealed that attractivenes...