Long-term effectiveness of 6 mm micro-rough implants in various indications: A 4.6- to 18.2-year retrospective study.

OBJECTIVES: To evaluate the long-term effectiveness of 6 mm implants in various indications with a micro-rough surface after 4.6-18.2 years in function and to assess key factors associated with implant survival, success, and biologic/technical complications. MATERIALS AND METHODS: Fifty-five patients with seventy-four 6 mm implants placed from 2000 to 2013 attended the re-examination assessing well-established clinical and radiographic parameters, biologic and prosthetic complications, and patient-reported outcome measures. RESULTS: Five implants were lost after a mean follow-up period of 9.1 years resulting in a survival rate of 93.2%. All losses occurred in free-end situations in the mandible. Smoking habit significantly reduced implant survival (hazard ratio 36.25). Two implants exhibited a history of peri-implantitis, and one implant showed progressive marginal bone loss (MBL) resulting in a success rate of 89.2%. The mean MBL amounted to 0.029 mm. Increased MBL was found for implants placed in the maxilla (0.057 mm) and for implants with a diameter of 4.1 mm (0.043 mm). Soft tissue thickness (1.39 mm) and width of keratinized mucosa (1.91 mm) had no effect on MBL. Patient-reported outcome measures showed high satisfaction (mean VAS scores 88%) and high quality of life (mean OHIP-G14 score 2.2). CONCLUSION: The present study demonstrated survival and success rates of 93.2% and 89.2% for 6 mm implants used in various indications. A factor leading to higher implant failure was smoking, whereas modulating factors increasing annual MBL included implants placed in the maxilla and implants with a diameter of 4.1 mm compared to 4.8 mm.

A retrospective analysis of autotransplanted teeth including an evaluation of a novel surgical technique.

OBJECTIVES: To assess survival rates and frequency of complications for immature and mature autotransplanted teeth after at least 1 year in function. MATERIALS AND METHODS: All consecutive patients who had undergone tooth autotransplantation between 2000 and 2018 were invited to a clinical and radiographic follow-up examination. First, survival rates were calculated on the basis of a phone inquiry. A clinical follow-up examination allowed for the calculation of the success rate, i.e., absence of any potentially adverse clinical and radiographic findings of the autotransplanted teeth. Moreover, the effect of demographic, dental, and surgical variables on survival/success was analyzed statistically. RESULTS: Thirty-eight teeth in 35 patients were transplanted during the study period. Three teeth in 3 patients were excluded due to missing records. All other patients were successfully contacted and interviewed by phone. Out of these 35 transplants, 32 were still in function, and 3 had been extracted, yielding a 91.4% survival probability after a median follow-up of 3.4 years. Of the 32 teeth qualifying for the success analysis, 20 (62.5%) showed absence of potentially adverse findings, while 3 (9.4%) required root canal treatment (RCT). Out of the 9 mature, root-end resected transplants, 4 exhibited ongoing pulp canal obliteration, all with a single root canal. Postoperative and potentially adverse findings or failures were found more frequently in the group of mature transplants (55.6%) than immature transplants (30.4%) and for molars (72.7%) than premolars (17.6%) or canines (25%). None of the potential predictors had a statistically significant effect on survival or success. CONCLUSION: Autotransplanted teeth yielded a satisfying midterm survival rate regardless of their stage of development. An additional, extraoral root-end resection of mature transplants may lead to rates of revascularization and postoperative pulp canal obliteration higher than the data reported on unmodified mature transplants. CLINICAL RELEVANCE: Extraoral root-end resection of mature teeth shows promising outcomes for transplants especially with a single root canal and uncomplicated root morphology.

Unique air inclusions within the nasopalatine duct indicating its presence radiographically: a case presentation.

The anterior maxilla is characterized by the nasopalatine canal that originates bilaterally from the anterior nasal floor, subsequently fuses, and terminates at the incisive foramen in the anterior palate. Embryologically, this structure forms within the primary palate, and contains the neurovascular bundle, but also continuous epithelialized bands. The latter, termed nasopalatine ducts, usually degenerate and/or obliterate before birth. However, in some individuals, the ducts may remain partially or completely patent. The present case report describes for the first time in the literature a rare finding of air inclusions within the anatomical area of the nasopalatine canal indicating the presence of a nasopalatine duct as visualized with cone beam computed tomography. The patient was asymptomatic and the radiographic findings were seen incidentally. An endoscopic inspection of the anterior nasal cavities confirmed the presence of the nasal openings of the partially patent nasopalatine ducts.

Frequency and type of incidentally detected radiodensities in the maxillary sinus: a retrospective analysis using cone beam computed tomography (CBCT).

OBJECTIVES: To evaluate the frequency, location, and characteristics of radiodensities in the maxillary sinus using cone beam computed tomography (CBCT). MATERIALS AND METHODS: All CBCT scans with a large field of view with both maxillary sinuses entirely visible were initially screened. Patients were included, if there was no suspicion of sinus pathology and no history of surgical intervention/trauma in the sinus region. The location and shape of the radiodensities were evaluated in axial, coronal, and sagittal CBCT views. The findings were correlated with age, gender, condition of the sinus mucosa, and status of the dentition. RESULTS: A total of 169 patients (338 maxillary sinuses) were included. Radiodensities were found in 35 sinuses (10.4%) of 28 patients (16.6%) with a mean age of 32.0 years. Most of the 35 affected sinuses had one radiodensity (19/54.2%). The radiodensities were typically located at the sinus floor (22/62.9%). Of the sinuses presenting with radiodensities, 17 (48.6%) were exhibiting reactive changes of the Schneiderian membrane. The presence of periodontal pathology was found to be associated with the presence of radiodensities. Age and sinus pathology were influencing factors on the shape of radiodensities, and the status of the dentition was an influencing factor on the number of lesions. CONCLUSIONS: One-sixth of the patients analyzed had incidentally diagnosed radiodensities in their maxillary sinuses. As almost 50% of the sinuses with radiodensities exhibited a form of chronic rhinosinusitis, the diagnosed ectopic calcifications may have formed as a result of mucosal changes of inflammatory origin. The presence of periodontal pathology was associated with a higher incidence of radiodensities. Nevertheless, this finding has to be interpreted with some caution due to the limited sample size available. CLINICAL RELEVANCE: Incidentally detected radiodensities in the maxillary sinus are not an infrequent finding in CBCT scans of asymptomatic patients, and are located typically on the sinus floor. Future studies are needed to assess the clinical significance of these findings especially with regard to planned surgical interventions in the posterior maxilla.

Distances of root apices to adjacent anatomical structures in the anterior maxilla: an analysis using cone beam computed tomography.

OBJECTIVES: The aim was to assess the anatomical relationship of anterior maxillary teeth to the nasal floor in patients referred for apical surgery. MATERIALS AND METHODS: Cone beam computed tomographic images (CBCT) of 83 patients were analysed retrospectively to quantify the distances between the root apices of maxillary anterior teeth (canine to canine) to the nasal floor or maxillary sinus (whichever was closer). Secondary outcome variables were the distances of the periapical lesion to the nasal floor, distances of the apices to the labial and palatal bone plates as well as to the neighbouring teeth. RESULTS: A total of 93 teeth (39 central, 35 lateral incisors and 19 canines) were analysed. The mean shortest distances of the apices to the nasal floor (or maxillary sinus) were 8.54 mm for central incisors, 9.49 mm for lateral incisors and 5.39 mm for the canines. The canines exhibited a significantly shorter distance to the nasal floor/maxillary sinus. In the presence of an osteolysis, the distance to the nasal floor was significantly shorter compared to the teeth without lesions. The lateral and central incisors showed significant proximity to each other at the level of the future surgical resection (3 mm from the apex). CONCLUSIONS: A close proximity between apices and adjacent anatomical structures such as nasal floor, maxillary sinus or adjacent roots could be shown in some cases. CLINICAL RELEVANCE: CBCT could be a valuable adjunctive imaging tool prior to apical surgery in the anterior maxilla to assess the risk for and decrease the incidence of damage to neighbouring anatomical structures such as the nasal floor, maxillary sinus or adjacent roots.

The Morphology of the Infraorbital Nerve and Foramen in the Presence of an Accessory Infraorbital Foramen.

BACKGROUND: The accessory infraorbital foramen (AIOF) is an anatomical variation associated with the infraorbital foramen (IOF) and nerve (ION). Its occurrence and neural contents have clinical implications regarding failure of loco-regional anesthesia and risk of neural damage during surgical interventions involving the maxillary region. Thus, morphologic characterization of the AIOF and neural contents as well as the spatial relationships to the IOF are potentially useful for optimizing surgical procedures. Additionally, predictive features of the AIOF based on its relationship to IOF morphology could enable the surgeon to anticipate its presence and proceed accordingly. The purpose of this study was to determine whether the presence of an AIOF and its neural contents affected the size, shape, and composition of the IOF and ION. The specific hypothesis tested was that the topography and fascicular composition of the ION and IOF differs between individuals possessing an AIOF and those lacking this anatomical variant. METHODS: Gross topographic features of the IOF (42 crania) were compared between specimens possessing (test) or lacking (control) an AIOF. Nerve fascicles of ION (60 cadaveric sides) were examined histologically and compared morphometrically between specimens presenting or lacking an AIOF. An additional sample of 30 crania was subjected to cone-beam computed tomography (CBCT) analysis to determine the course of the canal leading to the AIOF. RESULTS: The AIOF incidence was 47.6% (20 crania) and 32.1% of the sides (27 sides). A single AIOF was observed in 24 sides and double AIOF in three sides. The AIOF occurred bilaterally in 7 specimens (16.7%). The majority of AIOF (86.7%) were located superomedial to IOF. A slightly higher frequency of the AIOF was found in left side compared to the right. Using CBCT, a patient sample showed an AIOF incidence in 21 sides of 16 patients (65.6%). A single AIOF was observed in 19 sides. Only 1 double AIOF was found in the scans, whereas 3 were found in the dry skull group. The AIOF occurred bilaterally in 3 scans (10%). The majority of AIOF (90.4%) were located superomedial to the IOF based on the CBCT scans. The AIOF was consistently seen connected to the infraorbital canal and progressed superiorly and medially from the infraorbital canal to the maxillary surface. The size of the ION without an AIOF was not significantly different than the ION in the presence of an AIOF (1.45 × 10/1.32 × 10 µm, P < 0.35) based on fascicular area. However, the number of ION fascicles was greater in specimens without an AIOF compared to those showing this feature (15.15/12.71, P < 0.04) CONCLUSION:: Results indicate that the area of the ION is not affected by an AIOF, suggesting that the field of innervation of this area is not modified by its occurrence. However, the ION appears to divide more proximally into its component branches when the AIOF is present.

Characteristics and dimensions of the infraorbital canal: a radiographic analysis using cone beam computed tomography (CBCT).

PURPOSE: To analyze morphological characteristics and dimensions of the infraorbital canal-groove complex using cone beam computed tomography (CBCT), and to evaluate its relationship with adjacent anatomical structures. METHODS: This retrospective study included CBCT scans of 100 patients taken between January and May 2014. Linear measurements of the infraorbital canal (IOC), the infraorbital groove (IOG) and the infraorbital canal-groove complex (IOC/G) were performed. Morphological variants of the IOC related to the maxillary sinus were classified into three types depending on the extent of protrusion of the canal into the sinus. Angles between the IOC and specific landmarks were measured to determine the direction of the IOC relative to the axial (A-ant) and sagittal (A-horiz) planes. RESULTS: A total of 127 IOCs were analyzed. The mean length of the IOC/G was 29 ± 3.0 mm. This value comprised the mean distances of the IOC (24.4 ± 2.9 mm) and the IOG (4.6 ± 1.7 mm). For the different types of IOC morphology, Type 1 (IOC embedded in maxillary sinus roof) was the most common (n = 87, 68.5%). The mean angles of A-ant and A-horiz measured 48.9° ± 7.5° and 20.3° ± 7.9°, respectively. CONCLUSION: Knowledge of the IOC/G morphology and its variants is important for the prevention of infraorbital nerve injury due to anesthesia or surgical interventions in this area. The presented data of anatomical characteristics of the IOC/G could be helpful for the planning of surgeries in the maxillary region by means of CBCT imaging.

Frequency, location, and association with dental pathology of mucous retention cysts in the maxillary sinus. A radiographic study using cone beam computed tomography (CBCT).

OBJECTIVES: The purpose of the present study was to evaluate the frequency, locations, and dimensions of mucous retention cysts of the maxillary sinus and analyze potential associated dental pathology. MATERIALS AND METHODS: A total of 156 cone beam computed tomography (CBCT) scans were included in the analysis, resulting in an evaluation of 310 maxillary sinuses. The presence of mucous retention cysts (MRC) manifesting as dome-shaped radiopacities in the sinus was diagnosed. Their locations were recorded, and dimensions (mm) were measured in coronal and sagittal/axial slices. The patients were grouped into (a) patients/sinuses with MRCs (test), and (b) patients/sinuses with healthy or any other changes (control) for further comparison and evaluation. RESULTS: There were 40 sinuses (12.9%) with a presence of a total of 56 MRCs. The mean age of involved patients was 29.0 years. The analysis showed that gender, age, sinus side, status of dentition, endodontic status, and periodontal status did not have a significant influence on the presence of MRCs when compared between test and control groups. Age and endodontic status exhibited a significant association with cyst location. CONCLUSIONS: Most of the sinuses analyzed (79.5%) did not present any MRC, and only 28.6% of the cysts diagnosed were found on the floor of the maxillary sinus. The mean dimension of the MRCs measured 6.28 ± 2.93 mm. No influencing factors on the presence or absence of MRCs were found in the present study. CLINICAL RELEVANCE: Most MRCs were not located on the floor of maxillary sinus. Future studies should assess their impact on surgical interventions in the sinus.

The resection angle in apical surgery: a CBCT assessment.

OBJECTIVES: The primary objective of the present radiographic study was to analyse the resection angle in apical surgery and its correlation with treatment outcome, type of treated tooth, surgical depth and level of root-end filling. MATERIALS AND METHODS: In the context of a prospective clinical study, cone beam computed tomography (CBCT) scans were taken before and 1 year after apical surgery to measure the angle of the resection plane relative to the longitudinal axis of the root. Further, the surgical depth (distance from the buccal cortex to the most lingual/palatal point of the resection plane) as well as the level of the root-end filling relative to the most coronal point of the cut root face was determined. Treated teeth were categorized into four groups (maxillary and mandibular anterior and posterior teeth). The final material comprised 62 treated roots in 55 teeth. RESULTS: The mean calculated resection angle of all roots was 17.7° ± 11.4° (range -9.6° to 43.4°). Anterior maxillary roots presented the highest mean angle (25.8° ± 10.3°) that was significantly different from the mean angle in posterior maxillary roots (10.7° ± 9.4°; p < 0.001) and from the mean angle in posterior mandibular roots (15.1 ± 9.8°; p < 0.05). In roots with a shallow resection angle (≤20°), the rate of healed cases was higher than in roots with an acute resection angle (>20°), however without reaching statistical significance (p = 0.0905). Angles did not correlate either with the surgical depth or with the retrofilling length. CONCLUSIONS: Statistically significant differences were observed comparing resection angles of different tooth groups. However, the angle had no significant effect on treatment outcome. CLINICAL RELEVANCE: Contrary to common belief, the resection angle in maxillary anterior teeth was greater than in the other teeth. The surgeon is advised to pay attention to the resection angle when bevelling maxillary anterior teeth in apical surgery.

Evaluation of a possible association between a history of dentoalveolar injury and the shape and size of the nasopalatine canal.

OBJECTIVES: Maxillary incisors (MI) are often affected by dentoalveolar injury resulting in tooth devitalization and apical periodontitis. The aim of the present study was to analyze any association between a history of dentoalveolar injury and the shape and size of the nasopalatine canal (NC) using cone beam computed tomography (CBCT). MATERIAL AND METHODS: Patients were allocated to the trauma group if they had a history of dentoalveolar injury and a root filling in at least one MI and/or one missing MI. As controls, 100 matched-controlled (age and gender) patients were selected. NC dimensions including length, width at midway, and diameter of incisal and nasal foramen were measured in sagittal and axial CBCT planes. Furthermore, an evaluation of NC bulging signs, apical osteolysis of MI, and its fusion with NC was performed. RESULTS: In the trauma group (n = 96), 31.3 % had at least one missing MI, and 95.8 % had a root filling in a MI. The antero-posterior dimension of the incisive foramen (p = 0.02) and of the NC at midway (p = 0.04) was significantly larger in the trauma group. Significantly more cases with a bulging sign were found in the trauma (n = 19) than in the control group (n = 3, p = 0.001). An apical osteolysis was identified in 5.1 % of MI, and 12/38 did show a fusion with the NC. CONCLUSION: Wider dimensions of the NC and a bulging sign may suggest a former dentoalveolar injury to the anterior maxilla. Periapical osteolysis of central MI over 5 mm in diameter tends to fuse with the NC. CLINICAL RELEVANCE: In patients with a history of dentoalveolar injury and/or apical periodontitis, the NC should be evaluated on available CBCT images. Any inflammatory processes in the neighboring teeth should be recognized and eliminated as they may initiate bulging of the NC and/or the formation of a nasopalatine duct cyst (NPDC). NC with bulging signs should be monitored clinically and radiographically to diagnose a NPDC in an early stage.

Assessment of bone channels other than the nasopalatine canal in the anterior maxilla using limited cone beam computed tomography.

PURPOSE: The anterior maxilla, sometimes also called premaxilla, is an area frequently requiring surgical interventions. The objective of this observational study was to identify and assess accessory bone channels other than the nasopalatine canal in the anterior maxilla using limited cone beam computed tomography (CBCT). METHODS: A total of 176 cases fulfilled the inclusion criteria comprising region of interest, quality of CBCT image, and absence of pathologic lesions or retained teeth. Any bone canal with a minimum diameter of 1.00 mm other than the nasopalatine canal was analyzed regarding size, location, and course, as well as patient gender and age. RESULTS: A total of 67 accessory canals ≥1.00 mm were found in 49 patients (27.8%). A higher frequency of accessory canals was observed in males (33.0%) than in females (22.7%) (p = 0.130). Accessory canals occurred more frequently in older rather than younger patients (p = 0.115). The mean diameter of accessory canals was 1.31 ± 0.26 mm (range 1.01-2.13 mm). Gender and age did not significantly influence the diameter. Accessory canals were found palatal to all anterior teeth, but most frequently palatal to the central incisors. In 56.7%, the accessory canals curved superolaterally and communicated with the ipsilateral alveolar extension of the canalis sinuosus. CONCLUSIONS: The study confirms the presence of bone channels within the anterior maxilla other than the nasopalatine canal. More than half of these accessory bone canals communicated with the canalis sinuosus. From a clinical perspective, studies are needed to determine the content of these accessory canals.

Influence of hemostatic agents upon the outcome of periapical surgery: dressings with anesthetic and vasoconstrictor or aluminum chloride.

OBJECTIVE: To evaluate the effects of different hemostatic agents upon the outcome of periapical surgery. DESIGN: A retrospective study was made of patients subjected to periapical surgery between 2006-2009 with the ultrasound technique and using MTA as retrograde filler material. We included patients with a minimum follow-up of 12 months, divided into two groups according to the hemostatic agent used: A) dressings impregnated in anesthetic solution with adrenalin; or B) aluminum chloride paste (Expasyl). Radiological controls were made after 6 and 12 months, and on the last visit. The global evolution scale proposed by von Arx and Kurt (1999) was used to establish the outcome of periapical surgery. RESULTS: A total of 96 patients (42 males and 54 females) with a mean age of 40.7 years were included. There were 50 patients in the aluminum chloride group and 46 patients in the anesthetic solution with vasoconstrictor group. No significant differences were observed between the two groups in terms of outcome after 12 months - the success rate being 58.6% and 61.7% in the anesthetic solution with vasoconstrictor and aluminum chloride groups, respectively (p > 0.05). CONCLUSION: The outcome after 12 months of follow-up was better in the aluminum chloride group than in the anesthetic solution with vasoconstrictor group, though the difference was not significant.

[The mental foramen or "the crossroads of the mandible." An anatomic and clinical observation]. / Das Foramen mentale oder "the crossroads of the mandible." Eine anatomische und klinische Betrachtung.

This paper presents a clinical and anatomical review of the mental foramen (MF) based on recent publications (since 1990). Usually, the MF is located below the 2nd premolar or between the two premolars, but it may also be positioned below the 1st premolar or below the mesial root of the 1st molar. At the level of the MF, lingual canals may join the mandibular canal (hence the term "crossroads"). Accessory MF are frequently described in the literature with large ethnic variations in incidence. The emergence pattern of the mental canal usually has an upward and posterior direction. The presence and extent of an "anterior loop" of the mental canal may be overestimated with panoramic radiography. Limited cone-beam computed tomography currently appears to be the most precise radiographic technique for assessment of the "anterior loop". The mental nerve exiting the MF usually has three to four branches for innervation of the soft tissues of the chin, lower lip, facial gingiva and mucosa in the anterior mandible. The clinician is advised to observe a safety distance when performing incisions and osteotomies in the vicinity of the MF.

[Implant therapy following trauma of the anterior teeth ­ a new method for alveolar ridge preservation after post-traumatic ankylosis and external root resorption]. / Implantattherapie nach Frontzahntrauma. Eine neue Methode zum Erhalt des Alveolarkammes nach posttraumatischerAnkylose und externer Wurzelresorption.

The therapy of traumatized front teeth with ankylosis and additional root resorption is a real challenge for the clinician. Due to the infraposition ankylosed teeth are useless and esthetically unsatisfactory. The progressive replacement resorption and the vertical growth inhibition render an intervention inevitable. In the following case report, the prophylaxis of the alveolar ridge is brought into focus. The treatment of two ankylosed teeth by decoronation, preservation of the alveolar ridge and an implant-supported supraconstruction will be presented. The additional histological assessment confirms the diagnosis and the choice of treatment.

Cone beam computed tomography in mandibular molars referred for apical surgery.

INTRODUCTION: The purpose of the present study was to compare conventional intraoral periapical radiographs (PA) with limited cone beam computed tomography (CBCT) for evaluation of mandibular molars prior to apical surgery. The apical extent and homogeneity of the root canal fillings (RCF) as well as the number of root canals were examined. METHODS: 38 molars with 75 roots were included in the study. The apical extent and homogeneity of the RCFs as well as the presence of root canal posts or screws were examined on sagittal CBCT slices and on the PAs. The number of root canals was determined on sagittal CBCT slices and the PAs. The mesial and the distal roots were examined separately. RESULTS: Considerably more root canals were found on the CBCT slices compared to the PAs. The homogeneity and the extent of the RCFs as well as the presence of root canal posts or screws seem subjectively easier to determine on the PAs. CONCLUSION: In mandibular molars, because of the better discrimination of root canal anatomy we recommend a CBCT scan prior to apical surgery.

[Mucous retention cyst of the alveolar bone radiologically mimicking a radicular cyst: A case presentation.] / Aussergewöhnliche Schleimretentionszyste im Kieferknochen imponiert radiologisch als radikuläre Zyste. Ein Fallbericht.

One of the most frequent pathologies of jaw bone is a bacteria-induced inflammation at the apices of teeth with subsequent bone resorption that typically presents as a radiolucency in radiographs. Usually, corresponding clinical and radiographic findings correlate and allow for an accurate diagnosis. However, occasionally an unexpected and completely different diagnosis presents as documented in this case report. In a 55-year-old female patient, a radicular cyst was suspected in her right maxillary bone. The treatment plan included a cystectomy as well as apical surgery of the adjacent and root-canal filled teeth 15 and 16. However, the intraoperative finding absolutely did not fit a radicular cyst but rather a mucous retention cyst, as could be confirmed subsequently by histopathology. The diagnosis of a mucous retention cyst within the jaw bone is extraordinary and as such has never been described before in the literature.

Anatomical variations of the ethmoid sinuses and their association with health or pathology of the ethmoid and maxillary sinuses in a Southern Chinese population: An analysis using cone-beam computed tomography.

Purpose: The aim of this study was to evaluate the prevalence of clinically relevant anatomical variations of the ethmoid sinuses and their potential association with ethmoid and maxillary sinus pathologies on cone-beam computed tomography (CBCT) scans. Additionally, potential associations with different sides and demographic factors, including age and sex, were evaluated. Materials and Methods: In total, 273 CBCT scans with complete ethmoid and maxillary sinuses were analyzed to determine the prevalence of Agger nasi cell, supraorbital ethmoid cell, Haller cell, Onodi cell, and ethmomaxillary sinus. In addition, the health or pathology of the ethmoid and maxillary sinuses was also recorded to assess correlations with the aforementioned variations. Results: The prevalence of Agger nasi cell was found to be the highest (95.6%) in this study, followed by Onodi cell (60.4%), Haller cell (29.3%), and supraorbital ethmoid cell (19.4%). Ethmomaxillary sinus was the least common finding (16.5%). Males and persons above 61 years of age had a significantly higher frequency of supraorbital ethmoid cell and Onodi cell, respectively. However, no significant relationships were noted between anatomical variations of the ethmoid sinus and pathologies of the ethmoid or maxillary sinus. Conclusion: There was a high prevalence of ethmoid sinus variations in this Southern Chinese population. The prevalence of Agger nasi cell and Onodi cell was higher than that of other anatomical variations of the ethmoid sinuses. Anatomical variations of the ethmoid sinuses were not associated with ethmoid or maxillary sinus pathologies in this patient cohort.

Morphology of the nasopalatine canal and dental implant surgery: a radiographic analysis of 100 consecutive patients using limited cone-beam computed tomography.

OBJECTIVES: To analyze the dimensions and anatomic characteristics of the nasopalatine canal and the corresponding buccal bone plate of the alveolar process, using limited cone-beam computed tomography (CBCT) imaging. MATERIAL AND METHODS: Partially edentulous patients scheduled for CBCT imaging for further radiographic evaluation of a prospective implant recipient site in the anterior maxilla were consecutively enrolled in this study. For all CBCT images, a limited field of view (FOV) of 4 × 4 cm, 6 × 6 cm or 8 × 8 cm was selected. Reformatted sagittal and coronal slices were analyzed with regard to dimensions and anatomic characteristics of the nasopalatine canal as well as the dimensions of the buccal bone wall. Factors influencing these parameters were evaluated using univariate and multivariate linear regression models. RESULTS: The study population comprised 44 men and 56 women with a mean age of 43.09 years. Gender of the included patients had a statistically significant influence on the dimensions of the buccal bone plate, the mean values being generally higher for male subjects. In the multivariate linear regression model, the status of the central maxillary incisors (both present, one missing, and both missing) and the time elapsed since loss of the central incisors (<1 year vs. >1 year) were independently associated with buccal bone wall measurements, adjusted for age and sex. CONCLUSION: The present study demonstrates decreasing values for the coronal width of the buccal bone wall in patients with missing central incisors and a time span since tooth loss of over 1 year. The age of the patients had a significant influence only on the length of the nasopalatine canal, with the mean values generally decreasing with an increasing age. The limited CBCT scans with FOVs varying between 4 × 4 and 8 × 8 cm are a valid diagnostic alternative to cross-sectional imaging in the anterior maxilla for dental implant treatment planning.

Evaluation of location and dimensions of lingual foramina using limited cone-beam computed tomography.

PURPOSE: To assess retrospectively the frequency and location of mandibular lingual foramina and their bony canals with limited cone-beam computed tomography. PATIENTS AND METHODS: Of 389 consecutively taken cone-beam computed tomograms of the mandible, 191 fulfilled the inclusion criteria of adequate quality, dentate areas within the region of interest, and visualization of the mandibular inferior border. Foramina were located according to tooth areas and were grouped into midline, paramedian, and posterior foramina. Linear measurements included vertical and horizontal diameters of the foramen and its distance to the lower border of the mandible. In addition, the frequency of bony canals originating from lingual foramina was calculated, and the course and anastomoses with other anatomic structures were assessed. RESULTS: In total, 217 lingual foramina were detected in 1,054 sites. The midline of the symphysis had the highest frequency of foramina (96.2%), with the right first premolar area having the second highest frequency (27.5%). The mean diameter of lingual foramina ranged from 0.97 to 1.20 mm (horizontal diameter) and from 0.90 to 1.01 mm (vertical diameter). Sizes differed significantly between midline and posterior foramina. The mean distance from the foramen to the inferior mandibular border varied from 7.07 to 11.54 mm, with extreme outliers in all 3 groups. Overall, 95.4% of lingual foramina presented with a bony canal originating from the lingual surface, and 40.1% of these canals communicated with other anatomic structures, most frequently with the incisive canal. CONCLUSIONS: Mandibular lingual foramina and bony canals are frequently present and should be included in presurgical radiographic diagnostics.

Symptoms before periapical surgery related to histologic diagnosis and postoperative healing at 12 months for 178 periapical lesions.

PURPOSE: To compare the preoperative signs and symptoms with the histologic diagnosis and postoperative healing at 12 months for 178 periapical lesions. MATERIALS AND METHODS: A total of 152 patients who had undergone periapical surgery from 2005 to 2008 were studied. The study included patients presenting with signs and symptoms before periapical surgery with a sufficient tissue sample (periapical lesion) for histologic analysis and a minimal follow-up of 12 months. The signs and symptoms present in the soft tissues at the initial examination were recorded. The histologic analysis established the diagnosis as granuloma, cyst, or scar tissue. The postoperative healing at 12 months was evaluated according to the criteria of von Arx and Kurt. RESULTS: Of the 152 patients, 147, with 178 periapical lesions, were included in the present study. No significant relationship was found between the preoperative signs and symptoms, lesion type, and evolution. However, scar tissues were asymptomatic in 78.1%, and 36.4% of granulomas were painful. Of the 8 cysts, 50% were asymptomatic and 50% caused pain. Fibrous scars created no soft tissue alterations in 68.7%. Granulomas had fistulized in 31.7%, and 75% of cysts had produced no alterations. The lesions with swelling had worse healing, and those with no soft tissue alterations had better postoperative healing. CONCLUSIONS: Chronic periapical lesions (granuloma, cyst, and scar tissue) are usually asymptomatic and do not create soft tissue alterations. However, they can deteriorate, producing pain and fistulization. Worse postoperative healing was observed for lesions with swelling, although the difference was not significant.