Canine-premolar Area Research Articles

Anterior maxillary gingival overgrowth with associated submandibular lymphadenopathy

A 50-year-old Saudi woman presented to the Department of Oral and Maxillofacial Surgery, King Saud University Dental Hospital, Riyadh, Saudi Arabia, with a mucosal overgrowth related to the labial gingiva of the right maxillary second incisor and canine of about 10 months’ duration. The mass was slow-growing with no associated recent rapid growth before presentation. There was no history of trauma to the area. The patient was a known shammah (smokeless tobacco) user for over 40 years, usually placed alternately in the right and left anterior mandibular vestibule in the canine-premolar area.

Anatomic factors influencing dimensions of soft tissue graft from the hard palate. A clinical study.

ObjectivesThe aim of the present study was to measure the thickness of the palatal mucosa in a Jordanian (Middle Eastern) population as well as identify possible factors that may influence the thickness of palatal mucosa.Material and MethodsSixty period on tally healthy subjects (29 males and 31 females) were selected. Fifteen measurement points were defined on the palate. The mucosal thickness in the hard palate was determined by “bone sounding” with a Hu‐Friedy® round periodontal probe.ResultsThe overall mean thickness of the palatal masticatory mucosa was 3.23 ± 0.47 mm.The mean thickness increased from the gingival margin to a more apical position irrespective of the tooth measured or side of the mouth in the following sequence: canine, second molar, first premolar, second premolar and lastly, the first molar. No significant difference between gender, smoking status, gingival phenotype andsides of the mouth with the thickness of palatal masticatory mucosa was determined. A significant difference between palatal shape and palatal gingival thickness was found.ConclusionsThe most appropriate site for graft harvesting is the canine‐premolar area 8‐13 mm from the mid‐palatal aspect of each respective tooth in a Jordanian population. Except for the palatal shape, the side of the mouth, smoking, gender or gingival phenotype does not affect the graft harvest.Clinical Relevance Scientific Rationale for StudyKnowledge on the thickness of the masticatory mucosa is crucialin making decisions for surgical treatment modality and may affect surgical outcome. We measured the thickness of the palatal mucosa in a Jordanian population and identified possible influencing factors.Principal FindingsThe thickness varied according to the teeth and the canine to premolar region was found to be the appropriate donor site.Practical ImplicationsThis information on safe zone for graft harvest can guide the periodontist to make appropriate incisions and choose the appropriate location to obtain a graft of adequate thickness and dimensions.

Understanding Lateral Periodontal Cyst: A Case Report

AbstractLateral periodontal cysts (LPCs) are developmental in origin and are typically seen in the canine-premolar area in the mandible and less commonly in the maxilla. Reported rate of incidence of LPCs is less than 1%, and LPCs represent only 0.8% of entire central cysts of the maxillary bone. Despite its unique clinical and radiological presentation, it is finally diagnosed due to its unique histological characteristics. Here, we present one case with characteristic findings. The routine hematoxylin and eosin–stained sections revealed reduced enamel epithelium-like cystic lining that is made of thin, nonkeratinized stratified squamous epithelium along with some epithelial plaques. The clinical-radio-pathological correlation affirmed the diagnosis of LPC. The pathogenesis of LPC has been discussed.

Comparison of stress in implant-supported monolithic zirconia fixed partial dentures between canine guidance and group function occlusal patterns: A finite element analysis.

Background. Monolithic zirconia is an emerging material for crowns and bridges. The possibility of full digital design has made it an attractive alternative material for implant-supported prostheses. A proper design is vital in the success of such a prosthesis like any other. This study, in the shortage of scientific evidence, has tried to assess the stress distribution of occlusal forces inside the implant-prosthesis system of a 3-unit bridge made of monolithic zirconia. Methods. A 3-unit monolithic zirconia bridge supported by two implant fixtures placed on the teeth #13 and #15 was digitalized. It was converted to a mesh of 59000 nodes and 34000 elements. Five types of occlusal forces (one as vertical centric, two at 15º and 30º simulating canine pattern of lateral movement, and two at 15º and 30º simulating group function pattern) were applied. The stress distribution among all the components of the implant-bridge system was assessed using Ansys Workbench 14 software and finite element analysis. Results. The maximum stress was between 286 and 546 MPa, which were found in either the fixture‒abutment screw area or in the upper part of the pontic connector between the canine and first premolar. The maximum pressure increased with an increase in the angle of occlusal force. Significantly higher stress was recorded in the group function occlusal pattern. Conclusion. Monolithic zirconia can be promising in designing bridges in the canine‒premolar area. However, proper design is necessary with more attention to the connectors and types of occlusal forces.

FRACTURE RESISTANCE OF RELINED MICROWAVE-CURED HIGH IMPACT VERSUS CONVENTIONAL HEAT-CURED ACRYLIC RESIN MANDIBULAR DENTURE BASES: AN IN VITRO STUDY

Aim: This in vitro study aimed at comparing the fracture resistance of microwave-cured high impact and conventional heat-cured acrylic resin mandibular denture bases, whether relined by a resilient liner or not. Materials and methods: Conventional heat-cured (C) and high impact microwave-cured (H) acrylic resins were used in the fabrication of 24 mandibular denture bases divided into 4 groups (n=6). Half of these bases were 4 mm in thickness to be used unrelined (CU and HU), the other half was prepared in reduced thickness (2 mm thick) to be relined (CR and HR) with addition silicon resilient liner (R). The denture bases were loaded in compression at the canine-premolar areas bilaterally until failure, using a universal testing machine. Data on fracture resistance (N), work of fracture (J) and deflection at fracture (mm), were analyzed by Kruskal-Wallis and Dunn’s test (P≤0.05). Results: Among the unrelined (CU and HU) and the relined (CR and HR) bases, there were insignificant differences regarding the fracture resistance and the work of fracture median values. Fractures/cracks were repeatedly observed either unilaterally or bilaterally at the premolar regions of the bases. The CU bases exhibited the statistically lowest significant median deflection value at fracture compared to all other denture bases which were insignificantly different from each other. Conclusions: Relining of mandibular denture bases with resilient liners reduced their fracture resistance, work of fracture and increased their amount of deflection at fracture regardless to the type of the denture base material. Economically, conventional acrylic resin denture base material is still the material of choice for dentures that would require relining with resilient liners.

To Assess and Evaluate the Variation of Mandibular Anatomy Using Cone Beam Computed Tomography Before Planning an Implant Surgery: A Population-based Retrospective Study

The accurate placement of implants in mandible requires consideration for angulations of the bone along with the vertical dimensions. The aim of this present study was to assess the variation of mandibular anatomy using computed tomography (CT) radiography and to evaluate the effect of presence and absence of teeth on the mandibular anatomy before planning an implant surgery. The present population-based retrospective study was conducted using 167 digital CT scan images those selected from departmental archives. The samples were sub-divided two groups: group 1included digital CT of edentulous mandible while group 2 included digital CT of edentulous mandible. The axial height, vertical height, and angulations were recorded separately for each group. The results of the present study showed a gradual increase in mandibular angle in both the groups with a statistically significant difference only in the canine-premolar area. The axial height showed a significant difference at canine and first premolar area and a second premolar and the first molar area. However, available height showed a significant difference in canine and first premolar area and distal to the second molar area. When both the sides were compared, no statistically significant difference was observed between right and left sides. It was concluded that due to the variability of the mandibular anatomy and because of the effects of various imperative factors, 3D imaging like CT scans should be recommended for safer and secure presurgical planning. In surgical osteotomies and implant placement especially in post-extraction sockets, two-dimensional (2D) image of panoramic radiographs should not be considered that reliable as these three-dimensional (3D) imaging radiographs. Therefore CT scans of various angulations and sections must be considered by the clinicians to rationally study the mandibular anatomy and their risk associated areas.

Treatment of Midline Deviation with Miniscrews: A Case Report

A 15-year-old female presented with the chief complaint of crowding. Extraoral examination revealed little facial asymmetry, which was related with mandibular deviation caused by constriction of the maxilla. Upon intraoral examination, Class III molar and Class II canine relationships were seen on the right side, and Class III molar and Class III canine relationships were seen on the left side. A morphological lower midline shift was detected (4 mm to the right). After the start of treatment with rapid maxillary expansion, miniscrews were inserted into the buccal shelf and canine-premolar areas in order to solve the morphological deviation without extractions. Because there was a need to shift the lower midline to the right side, miniscrews were inserted into the left buccal shelf at the right canine-premolar area. The miniscrews were placed vertically so that the angle between the long axes of the teeth and the long axes of the screws were approximately 20 degrees. Acceptable correction of the midline deviation lasted for four months. At the end of the treatment, a good occlusal relationship was obtained.

Osseointegration of titanium implants with SLAffinity treatment: a histological and biomechanical study in miniature pigs.

Electrochemical oxidation following sandblasting and acid-etching (SLA) treatment has received interest as a surface modification procedure for titanium (Ti) implants (denoted as an SLAffinity surface); however, little information is available on its impacts on the in vivo performance of SLAffinity-Ti implants. The present study evaluated the osseointegration and biomechanical bone-tissue response to SLAffinity-Ti implants with micro- and nanoporous oxide layers. The interaction between blood and the tested implants was examined. In total, 144 implants with the following surfaces were used: a standard machined (M-Ti), an SLA-Ti, and an SLAffinity-Ti surface. For each animal, four implants (one M-Ti, one SLA-Ti, and two SLAffinity-Ti) were inserted into the mandibular canine-premolar area for histomorphometric observations and another four implants were inserted into the flat surface on the anteromedial aspect of the rear tibia for removal torque (RT) tests. After 2, 4, and 8weeks of implantation, histomorphometric and RT tests were conducted. Interactions between blood and implants were better for implants with the SLAffinity-Ti surface. RT tests showed a significant improvement in fixation strength for SLAffinity-Ti implants (84.5 ± 8.7N-cm) after 8weeks compared to M-Ti (62.95 ± 11.5N-cm) and SLAffinity-Ti (76.1 ± 6.6N-cm) implants. A histological evaluation showed that osseous integration had occurred with all implants after 8weeks. SLAffinity-Ti implants exhibited 28.5 ± 6.2% bone-to-implant contact (BIC) at 2weeks and 84.3 ± 8.1% at 8weeks. M-Ti implants exhibited BIC levels of 17.0 ± 5.4 and 76.5 ± 6.3%, whereas SLA-Ti implants exhibited BIC levels of 28.5 ± 6.2 and 81.1 ± 8.4% at corresponding time intervals. In terms of the peri-implant bone area (BA), values for SLAffinity-Ti implants ranged from 29.5 ± 4.1 to 88.3 ± 3.0%. For M-Ti implants, values ranged from 20.3 ± 5.5 to 81.7 ± 4.2%. For SLA-Ti implants, values ranged from 23.0 ± 3.5 to 84.0 ± 3.6%. Electrochemical oxidation increased the oxide layers and improved the blood interaction with SLAffinity-Ti implants, resulting in significantly higher bone apposition with the SLAffinity-Ti implants after 2 and 8weeks of healing. An increase in resistance for the RT of SLAffinity-Ti implants over the 8-week healing period was also observed. The use of SLAffinity-Ti implants has potential for improvement of early osseointegration.

Early bone response to machined, sandblasting acid etching (SLA) and novel surface-functionalization (SLAffinity) titanium implants: characterization, biomechanical analysis and histological evaluation in pigs.

The purpose of the present study was to examine early tissue response and osseointegration in the animal model. The surface morphologies of SLAffinity were characterized using scanning electron microscopy and atomic force microscopy. The microstructures were examined by X-ray diffraction, and hardness was measured by nanoindentation. Moreover, the safety and toxicity properties were evaluated using computer-aided programs and cell cytotoxicity assays. In the animal model, implants were installed in the mandibular canine-premolar area of 12 miniature pigs. Each pig received three implants: machine, sandblasted, large grit, acid-etched, and SLAffinity-treated implants. The results showed that surface treatment did affect bone-to-implant contact (BIC) significantly. At 3 weeks, the SLAffinity-treated implants were found to present significantly higher BIC values than the untreated implants. The SLAffinity treatments enhanced osseointegration significantly, especially at early stages of bone tissue healing. As described above, the results of the present study demonstrate that the SLAffinity treatment is a reliable surface modification method.

Rapid Osseointegration of Titanium Implant With Innovative Nanoporous Surface Modification: Animal Model and Clinical Trial.

SLAffinity is the hybrid topography consisting of micropits and nanoporous TiO2 layers through electrochemical oxidation to mimic the natural bony environment. The aim of this study was to examine the rate of osseointegration in animal models and to further investigate the stability for implants with SLAffinity-treated surface in the clinical trial. Implants were installed in the mandibular canine-premolar area of 12 miniature pigs. Each pig received 2 implants with the same shapes but with different chemical surfaces. In the clinical trial, 25 patients were included. Each patient received 1 SLAffinity-treated implant on the posterior area of either arch. Resonance frequency analysis and computed tomography were assessed weekly over the first 12 weeks after implant placement. The results found that surface treatment did affect the bone-to-implant contact (BIC) significantly. Comparison of BIC at 3 weeks in animal study showed that the SLAffinity-treated implants presented significantly higher values than machine surface implants. SLAffinity-treated implants also proved clinically successful through 12 months, ready for prosthodontic restoration. The effect of SLAffinity treatments enhanced osseointegration significantly, especially at early stages of bone healing. Clinical trial finding, furthermore, ensured that the SLAffinity treatment was a reliable surface modification alternative.

Gingival Cyst of the Adult: Regenerative Therapy of Associated Root Exposure. A Case Report and Literature Review

The gingival cyst of the adult (GCA) is an uncommon developmental cyst of odontogenic origin most frequently seen near mandibular canines and premolars and is routinely treated with excisional biopsy. This article presents a case of a GCA treated with a combined regenerative approach and reviews the GCA literature with an emphasis on the clinical aspects of this lesion. A 54 year-old man presented for treatment of generalized severe chronic periodontitis. Clinical examination revealed a cystic lesion in the gingiva of the mandibular canine-premolar area. Radiographs revealed a well-defined radiolucency in the coronal one-third of the tooth roots. Surgical enucleation of the lesion revealed root exposure of the second premolar. Because of the anatomy of the lesion-associated defect, regenerative treatment, using a combination of freeze-dried bone allograft and a collagen membrane, was considered the therapeutic approach of choice. The biopsy revealed histologic features consistent with a GCA. Clinical and radiographic examinations 1 year post-surgery indicated uneventful soft tissue healing and bone fill of the initial defect. The review of the literature revealed only one other case of root exposure associated with GCA and no previous report of regenerative therapy. In rare instances, a GCA lesion may result in tooth-root exposure. In such cases, a combined regenerative treatment approach may be used to achieve resolution.

Effect of buccolingual root angulation on the mesiodistal angulation shown on panoramic radiographs

The purpose of this study was to evaluate the effect of buccolingual root angulation on the perception of root parallelism in panoramic images. A skull-typodont device was constructed according to cephalometric norms. The bases of the typodont were partially sectioned so that the buccolingual orientation of 4 adjacent pairs of teeth could be easily modified. Three buccolingual angulations were used for each tooth. Nine image sequences were necessary to analyze all possible buccolingual orientation combinations between adjacent teeth. The true root parallelism angulations relative to an orthodontic archwire were compared with the angulations obtained from scanned panoramic films. The largest root parallelism differences for adjacent teeth occurred between the maxillary canine and the first premolar. The second largest differences occurred in the mandibular canine-premolar area. No significant differences were found in the incisor area. The root parallelism expression in the canine-premolar region can be modified by altering the buccolingual orientation. Buccolingual orientation changes do not seem to affect the incisor area. The clinical usefulness of panoramic radiography to assess root parallelism should be approached with caution, especially in premolar extraction sites.

Near-End of Treatment Panoramic Radiograph in the Assessment of Mesiodistal Root Angulation

To test the hypothesis that there is no difference between the actual mesiodistal root angulation and the mesiodistal root angulation as measured on the panoramic radiograph. A typodont dentition was set up into a Class I occlusion. Wire struts were placed on the buccal surface of each tooth to represent their long axes. The dentition was fixed into a natural skull for imaging. The radiographic and true mesiodistal angulation of each tooth to a horizontal reference plane (the arch wire) was measured using a coordinate measuring machine (CMM). The mesiodistal root positions were then altered to a more mesial and then more distal position and the measurements were repeated. Only 26.7% of the radiographic root angulations were within the clinically acceptable angular variation range of +/-2.5 degrees . The greatest variation in the upper arch occurred in the canine-premolar area where the roots were projected as being more divergent. The greatest variation in the lower arch occurred in the lateral incisor-canine region where these roots were projected as being more convergent. The extent of radiographic distortion is statistically greater in the lower arch than in the upper arch in the ideal (P < or = .05) and distal (P < or = .01) root positions. The hypothesis is rejected. There is a clinically significant variation between the radiographic and the true root angulations recorded. Caution is advised when interpreting mesiodistal root angulation using this radiograph.

Bilateral Gingival Swellings in the Mandibular Canine–Premolar Areas

A bilateral occurrence of gingival cyst of the adult has been presented. A comparison of the gingival cyst and lateral periodontal cyst indicates that these lesions may represent intraosseous and extraosseous counterparts. Criteria for differentiation of the two similar lesions were presented. Because not all lesions are clinically apparent, the frequency of occurrence of this cyst may be underestimated.