Gum disease NYC risk factors: what you need to know for healthy gums

How old are you?
The chance of developing gum or periodontal disease increases considerably as you get older. Studies indicate that older people have the highest rates of periodontal disease and need to do more to maintain good oral health. However, as you read ahead, if you are a young patient (under 40 years old) and have any of the risk factors, you may have more serious dental problems that will worsen with time and require professional treatment in a timely way.

Are you female or male?
Studies suggest there are genetic differences between men and women that affect the risk of developing gum disease. While women tend to take better care of their oral health than men do, women's oral health is not markedly better than men's. This is because hormonal fluctuations throughout a woman's life can affect many tissues, including gum tissue.

Do your gums ever bleed?
Bleeding gums can be one of the signs of gum disease. Think of gum tissue as the skin on your hand. If your hands bled every time you washed them, you would know something was wrong. However if you are a smoker, your gums may not bleed, and therefore, “hide” the severity of your condition.

Are your teeth loose?
Periodontal (gum) disease is a serious inflammatory disease that is caused by a bacterial infection, and leads to destruction of the attachment fibers and supporting bone that hold your teeth in your mouth. When neglected, teeth can become loose and fall out. Loose teeth, even though nothing hurts, are a sign of periodontal or gum disease.

Have your gums receded, or do your teeth look longer?
One of the warning signs of gum disease includes gums that are receding or pulling away from the teeth, causing the teeth to look longer than before.

Do you smoke or use tobacco products?
Studies have shown that tobacco use may be one of the most significant risk factors in the development and progression of periodontal disease. Smokers are much more likely than non-smokers to have calculus form on their teeth, have deeper pockets between the teeth and gums, and lose more of the bone and tissue that support the teeth. And yet, smokers may have no signs or symptoms of gum disease because the smoke masks the underlying problems.

Have you seen a dentist in the last two years?
Daily brushing and flossing will help remove bacterial plaque and even keep calculus formation to a minimum, but it won't prevent gum disease or calculus from forming. A professional dental cleaning at least twice a year is necessary to remove calculus from places your toothbrush and floss may have missed. If you are prone to gum disease, more frequent professional cleanings will help maintain your periodontal condition.

How often do you floss?
Studies demonstrate that including flossing as part of your oral care routine can actually help reduce the amount of gum disease-causing bacteria found in the mouth, therefore contributing to healthy teeth and gums. Brushing, alone, will not keep your mouth and gums healthy.

Do you currently have any of the following health conditions?
i.e. Heart disease, osteoporosis, osteopenia, high stress, or diabetes
Ongoing research suggests that periodontal disease may be linked to these conditions. The bacteria associated with periodontal disease can travel into the blood stream and pose a threat to other parts of the body. Healthy gums may lead to a healthier body. High stress levels release hormones into the bloodstream that act as “food” for the bacteria that cause gum disease. When you are under stress, you are “feeding” the problem.

Have you ever been told that you have gum problems, gum infection or gum inflammation?
Over the past decade, research has focused on the role chronic inflammation may play in various diseases, including periodontal or gum, disease. Data suggests that having a history of periodontal disease makes you six-times more likely to have future periodontal problems. Periodontal disease is often silent, meaning symptoms may not appear until an advanced stage of the disease.

Have you had any adult teeth extracted due to gum disease?
Most gum problems are generalized among a number or teeth, and are not isolated to a single tooth. For this reason, if you have lost a tooth to gum disease, the likelihood exists that you have a gum condition that needs to be treated, even if nothing hurts or you are unaware of any symptoms.

Have any of your family members had gum disease?
Research suggests that the bacteria that cause periodontal disease can pass through saliva, and remain on your toothbrush. For this reason, it is unwise to share toothbrushes. Individuals with advanced gum problems should be aware that they can transmit this to another family member through their saliva. Also, research proves that up to 30% of the population may be genetically susceptible to gum disease. Despite aggressive oral care habits, these people may be six times more likely to develop periodontal disease.

Gum disease, also known as periodontal disease, is a silent disease. It is chronic, much in the way diabetes, lupus, rheumatoid arthritis and other diseases are, and as such, must be treated, contained, and monitored by a dental professional. Except in extreme instances, early intervention will help an individual save their teeth in comfort and good function when suffering gum disease in NYC.

Dental 3D Cone Beam CT Imaging: Part V Dental Incidentalomas (Pre-surgical analysis for the insertion of dental implants)

Using 3D CT imaging for diagnostic purposes in medicine has uncovered incidental tumors that had no clinical symptoms in various tissues when there was no previous suspicion that they were present. These incidental tumors have been dubbed “incidentalomas,” and been discovered in adrenal glands, kidneys, pituitary glands, thyroid glands, liver, lungs, and the parathyroid glands (1-18). It has been estimated that approximately 7% of all patients over 60 may harbor a benign growth (often of the adrenal gland) and with the increase of “whole-body CT scanning” as part of health screening programs, the chance of finding incidentalomas is expected to increase to 37% (19). These chance findings will, in many cases, require further investigation.

A search of the dental literature did not reveal any studies that dealt with incidental findings on 3D CT studies taken on cone beam scanners. Nor has the term “incidentaloma” been applied to dentistry.

In this 3D CT cone beam study, 500 consecutive patients sent to one of nine i-dontics, llc radiologic labs were analyzed for a variety of normal and abnormal findings. Part I studied why patients were referred for CT studies including their age, gender, and format of the requested study. Part II studied the lingual artery and its insertion into the mandible. Part III studied the frequency and location of bifid canals. Part IV studied the length and location of the anterior canal extending anterior to the mental foramen. And in this study, Part V, the frequency and type of incidental findings on patients ostensibly sent to a dental CT radiological lab for 3D scans for dental implants were analyzed.

Methods and Materials

Data from five hundred (500) consecutive patients sent for 3D CT cone beam studies to one of 9 centers located in 3 states were evaluated. Scans were taken on either i-CAT (8 centers) or on a NewTom 3G scanner, and uploaded to a central data center. All studies were converted to SimPlant™ (Materialise, Glen Burnie, MD.). When not specified, the data was converted to SimPlant™ version 10.

In this part of the 3D study, the following parameters were recorded for each patient: if the maxillary sinuses were free of pathology or to what extent pathology was present. In addition, the following were noted: the presence of radiolucencies at the apices of teeth; were the teeth noted with radiolucencies vital or non-vital; impacted teeth and supernumeraries, retained roots, cysts, the presence of dental implants, and the radiopaque presence of bone graft material. Other incidental findings noted on the 3D Ct images included the notation of severe periodontal bone loss, fourth molars, condensing osteitis, surgical tacks, etc.
Results

Five hundred (500) patients were included in this study. Of the five hundred, two hundred and four (204) were referred exclusively for maxillary studies and an additional seventy-nine (79) (refer to Part I of this study), were referred for both maxillary and mandibular studies. A total of two hundred and eighty-three maxillas studied (Figure 1) for observations about the maxillary sinus. The CT scans for all 500 patients were analyzed for incidental findings.

Figure 1. Of the 500 patients in this study, 279 had maxillary scans evaluated.

Ninety-one (91) patients had both maxillary sinuses free of pathology while ninety (90) patients had pathology in both sinuses at the same time, as noted on the CT images. Pathology was defined as less than 1mm of a mucosal thickening measured at any part of the sinus visible in the CT scan. When pathology was present (1mm or greater of mucosal thickening), one maxillary sinus remained clear or free of pathology in 78 patients: 41 in the right and 37 in the left.

When present, the amount of mucosal thickening was measured in each sinus. The mucosal thickening in the right sinus averaged 5.3mm and it measured 5.6mm in the left sinus.

In addition, 26 patients had polyps in the right maxillary sinus and 22 patients had polyps in the left maxillary sinus. Six maxillary sinuses were totally blocked both right and left (Figure 2). Polyps were observed in some patients with mucous thickenings, so that the total number of observations is greater than the 283 maxillary sinuses studied.

Figure 2. 91 of the 283 maxillary scans had no pathology in both the right and left maxillary sinuses. 90 patients had pathology noted in both maxillary sinuses and 78 patients had pathology in only one of the maxillary sinuses. 48 patients had a polyp noted in either the right or left maxillary sinus, or both.

Reasons for dental 3D CT scans. The predominant reason for referral for dental CT scans was for pre-surgical analysis for the insertion of dental implants. Four hundred and fifty-one patients (451) were referred for implants; 20 for impacted teeth; 10 for pathology; 7 for endodontics; 4 for orthodontics; 1 for TMJ disorder; 7 unknown (Figure 3).

Figure 3. A = 451 Patients referred for CTs for implants; B = 20 patients for impacted teeth; C = 10 patients for pathology; D = 7 patients for endodontics; E = 4 patients for orthodontics; F = 1patient for TMJ; G = 7 patients unknown reason for referral for CT.

Incidental findings. While 451 patients (out of 500) were referred for a 3D dental CT scan for the express purpose of pre-surgical planning for implant insertion, many incidental findings were noted. The most common incidental findings (Figure 4) were periapical radiolucencies (229), socket preservation bone grafts (46), impacted teeth (27), retained root tips (24), sinus grafts (12), cysts (8), and supernumerary teeth (2). In addition, 70 dental implants were previously inserted in these patients. Other observations (142) included cementomas, surgical screws and tacks, assorted opacities within the body of either arch, 4th molars, blunted apices (due to orthodontics), blocked ethmoid sinus, condensing osteitis, and advanced periodontal disease nearly to the apices of many teeth.

Figure 4 The most common incidental findings were: 229 periapical radiolucencies; 46 socket preservation bone grafts; 27 impacted teeth; 24 retained root tips; 12 sinus grafts; 8 cysts; 2 supernumerary teeth.

Discussion

In the medical literature, the term “incidentaloma” refers to the discovery of a previously unsuspected tumor when taking a CT scan for another purpose. This term has not entered the dental literature. It is suggested that a dental “incidentaloma” be defined as the discovery of any unsuspected pathology, anomaly, dental structure (such as a retained root tip, impacted tooth, or supernumerary), or deviation from normal anatomy on a CT scan. The implications of these findings challenge the dentist and dental surgeon to be familiar with both normal and abnormal structures as they present on 3D cone scan imaging, which can appear different and unfamiliar compared to traditional 2D X-ray images such as periapical dental films or panoramic X-rays. Furthermore, it is incumbent for the dentist to interpret the entire field of view of each CT scan, and not just the area of concern, such as a dental implant site or a recalcitrant endodontic lesion or where the IAN is relative to an impacted third molar.

The most frequent incidental finding in this study was periapical radiolucencies. Many authors have acknowledged that 3D cone beam CT scans are extremely accurate and can be relied on for making a diagnosis of periapical pathology (20-23). For purposes of this study, periapical pathology was defined as a lesion expanding larger than 1mm from the apex. This was chosen to remove doubt that a pseudoperiapical lesion was not a thickened PDL due to trauma from occlusion. There was no attempt to obtain the previous history of teeth with root canal therapy to compare the size of the present lesion with past X-rays. No determination was made if a periapical lesion noted in this study was old, non-expanding, or a healing granuloma.

This 3D CT study noted trends in therapy. For instance, 46 extraction sockets were treated with graft material and the dental surgeon was interested in a 3D analysis of the healing lesion. Likewise, patients who had previously had maxillary sinus grafts (12) received 3D CT scans to determine the success of these surgeries.

Twenty-seven (27) teeth other than the ones patients who were originally referred for CT scans, were impacted, and two supernumeraries were noted. These “incidental” findings were sent in a report to each dentist for their review, final approval, and action when they deemed it necessary.

It is apparent that with the advent of dental cone beam scanners, more dentists will take advantage of 3D technology for better surgical planning, improved diagnostic preparation for orthodontic patients, all of which contribute to lower risk and more successful outcomes for the patients. While dentists embrace 3D technology, they need to become familiar with normal and abnormal landmarks. In addition, they need to be prepared to identify incidental findings and inform their patients as to the existence of these findings and their clinical relevance.

Conclusion

This study noted many incidental findings on 3D dental CT scans and suggests that these findings be described as “incidentalomas.” These unexpected findings include sinus pathology, cysts, impacted teeth, supernumeraries, periapical radiolucencies, and more. It is suggested that dentists become more familiar with normal and abnormal landmarks in the increased field of view of CT studies, especially when these 3D images are taking in preparation for dental implant treatment planning.
Acknowledgements: Support for this study was generously given by Nobel Biocare AB Gothenberg, Sweden (Grant 2006-492) and Imaging Sciences Inc., Hatfield, PA.

References

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2. Young WF. Clinical practice. The incidentally discovered adrenal mass. N. Engl. J. Med. 356 (6): 601–10, 2007

3. Reddan DN, Raj GV, Polascik TJ. Management of small renal tumors: an overview. Am. J. Med. 110 7: 558–62, 2001.

4. Remzi M, Ozsoy M, Klingler HC, et al. Are small renal tumors harmless? Analysis of histopathological features according to tumors 4 cm or less in diameter. J. Urol. 176 (3): 896–9, 2006

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6. Molitch ME. Pituitary incidentalomas. Endocrinol. Metab. Clin. North Am. 26 (4): 725–40, 1997

7. Steele SR, Martin MJ, Mullenix PS, Azarow KS, Andersen CA. The significance of incidental thyroid abnormalities identified during carotid duplex ultrasonography. Archives of surgery (Chicago, Ill. 1960) 140 (10): 981–5, 2005

8. Castro MR, Gharib H . Continuing controversies in the management of thyroid nodules. Ann. Intern. Med. 142 (11): 926–31, 2005

9. Shetty SK, Maher MM, Hahn PF, Halpern EF, Aquino SL. Significance of incidental thyroid lesions detected on CT: correlation among CT, sonography, and pathology. AJR. American journal of roentgenology 187 (5): 1349–56, 2006

10. Papini E, Guglielmi R, Bianchini A, et al. Risk of malignancy in nonpalpable thyroid nodules: predictive value of ultrasound and color-Doppler features. J. Clin. Endocrinol. Metab. 87 (5): 1941–6, 2002

11. Gould MK, Fletcher J, Iannettoni MD, et al. Evaluation of Patients With Pulmonary Nodules: When Is It Lung Cancer?: ACCP Evidence-Based Clinical Practice Guidelines (2nd Edition). Chest 132 (3_suppl): 108S–130S, 2007

12. Mirilas P, Skandalakis JE. Benign anatomical mistakes: incidentaloma. The American surgeon 68 (11): 1026–8, 2002

13. Yanagi Y, Asaumi J, Maki Y, Murakami J, Hisatomi M, Matsuzaki H, Konouchi H, Honda Y, Kishi K. Incidentally found and unexpected tumors discovered by MRI examination for temporomandibular joint arthrosis. European Journal of Radiology, Volume 47, Number 1, July 2003 , pp. 6-9(4)

14. Inagaki K, Otsuka F, Miyoshi T, Watanabe N, Suzuki J, Ogura T, Makino H. Reversible pituitary dysfunction in a patient with Cushing’s syndrome discovered as adrenal incidentaloma. Endocr J. 51(2):201-6., 2004.

15. Moretti, A, Bernini G, Argenio G, Salvetti A. Primary hyperaldosteronism in normokaliemic patients with adrenal incidentalomas. Am J Hypertens 14, 254A–254A: 672: 2001

16. Miyoshi T, Otsuka F, Suzuki J, Inagaki K, Kano Y, Ogura T, Kiura K, Saika T, Makino H. Abrupt enlargement of adrenal incidentaloma: a case of isolated adrenal metastasis. Endocr J. 54 (5):829, 2007

17. El Fakih RO, Encel ML, Kumar, NG Lung Incidentaloma November 1, 2008 Consultant. Vol. 48 No.

18. Howlett DC, Speirs A. The Thyroid Incidentaloma—Ignore or Investigate? J Ultrasound Med 26:1367-1371, 2007

19. Furtado CD, Aguirre DA, Sirlin CB, et al. Whole-body CT screening: spectrum of findings and recommendations in 1192 patients. Radiology 237 (2): 385–94, 2005

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21. Nakata K, Naitoh M, Izumi M, Inamoto K , Ariji E , Nakamura H. Effectiveness of Dental Computed Tomography in Diagnostic Imaging of Periradicular Lesion of Each Root of a Multirooted Tooth: A Case Report . ?Journal of Endodontics, 32:583 – 587,? 2006

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Dental 3D Cone Beam CT Imaging: Part IV Anterior Extension of IAN from Mental Foramen (Pre-surgical analysis for the insertion of dental implants)

Dental 3D CT cone beam imaging has many purposes including accurate dental implant placement and the identification of key anatomic structures. While there is an extensive literature analyzing the many aspects of the anterior loop extending from the mental foramen which compare the frequency and accuracy of this landmark from radiographs, cadaver dissection, and CT imaging (1-5), no study has measured the anterior extension of the inferior alveolar nerve (IAN) relative to distance from the edentulous crest, apices of teeth, and more. In Greenstein and Tarnow’s exhaustive literature review of the anatomy and clinical ramifications of the mental foramen, they conclude that since there is little correlation between viewing the anterior loop on radiographic and its actual clinical location, they recommend “leaving a 2mm zone of safety between an implant and the coronal aspect of the nerve” (6). In their literature review, it is suggested to use CT scans to help identify the anterior loop. They recommend that particular attention to variations in the anatomy in the area of the mental foramen be considered in addition to both functional and esthetic demands in order to avoid complications to the neurovasculature.

This study, using dental cone beam 3D CT scanners, evaluated various normal and abnormal landmarks noted in 500 consecutive patients referred to dental CT radiological labs for a variety of reasons, but most of which were for the insertion of dental implants. Part I of this study analyzed the demographics and reasons for the patients being referred for CT scans; Part II studied anatomic considerations of the insertion of the lingual artery into the mandible; Part III analyzed the frequency and location of bifid canals. In this study, Part IV, the anterior extension of the inferior alveolar nerve is studied on 3D CT images, and its clinical ramifications are discussed.

Methods

Data from five hundred (500) consecutive patients sent to i-dontics center from 9 centers located in 3 states for 3D dental CT studies, were evaluated. Scans were taken on either i-CAT (8 centers) or NewTom 3G scanners and uploaded to a central data center. All studies were converted to SimPlant™ (Materialise, Glen Burnie, MD). When not specified, the data was converted to SimPlant™ version 10.

Two hundred and Ninety-six (296) mandibles were studied on 3D CT studies using the measuring tool on the SimPlant Master™ Program. The following were measured: the length of the anterior extension of the IAN from the most mesial aspect of the mental foramen as identified in a 1mm slice; the distance of the anterior extension from the edentulous alveolar crest; the distance of the anterior extension from the apices of teeth; how many anterior extensions of the IAN were connected from right to left at the midline; and how many mental foramina were located on the alveolar crest.

Results

Almost 97% of the 296 mandibles analyzed in this study had at least one measurable extension of the IAN anterior to the most mesial aspect of the mental foramen (Figure 1), as noted on cone beam dental CT studies.


Figure 1. Nearly 97% of all mandibles had an anterior extension; nine patients did not have a measureable anterior extension of the IAN as seen on a 3D cone beam study.

Fourteen patients (4.73%) did not have an extension on the right side; eleven patients (3.72%) did not have an extension on the left side.

The average length of the anterior extension extending from the mesial rim of the mental foramen is 12.0 mm on the right and 11.8 mm on the left (Figure 2).


Figure 2. The average length of the anterior extension from the mental foramen bilaterally is nearly 12.0 mm.

The distance from the superior most portion of the anterior extension of the IAN to the edentulous crest was measured on images from a 3D dental cone beam scanner. In most instances, the bone loss was level and the radiographic extension was parallel to the crest enabling a single measurement either on the right or left side, or both. The average depth of the extension under an edentulous right crest was 10.5mm and 11.0mm under the left side (Figure 3-3A).


Figure 3. Average measurement to edentulous alveolar crest was 10.5mm on right anterior mandible. (Stereolithographic model courtesy of BioMedical Modeling, Boston, MA).


Figure 3A. Average measurement to edentulous alveolar crest was 11.0mm on left anterior mandible. (Stereolithographic model courtesy of BioMedical Modeling, Boston, MA).

The distance from the anterior extension of the canal to the apex of a tooth measured from 3D CT images when the dentition was present was measured from the most anterior extent of the canal vertically to the apex of the adjacent tooth. The preponderance of teeth measured in this situation were situated under the apices of the lateral incisors. In all instances, the measurement was vertical from the tooth apex to the top of the extended canal. Both right and left measurements, seen on 3D CT images, were identical: 17.0mm from the anterior extent of the canal to the nearest root apex.

A continuous loop, defined as an extension of the canal that emanates from both the right and left mental foramina and is seen to connect in the midline was viewed on 77 patients (26.01%). In Figure 4, the anterior extensions of the canal can be seen in different coronal (panoramic) slices of the same individual.


Figure 4. Coronal slices in the same patient demonstrate examples of a continuous canal as observed and noted in this study.

Figures 5 and 5A demonstrate a continuous anterior extension that joins in the midline. Various branches emanate from the canal displaying that may be viewed in CT cone beam images but not 2D dental X-rays.


Figure 5. Example of a continuous anterior extension of the canal with multiple branches extending from the main trunk.


Figure 5A. Some of the many branches extending from the main canal and the anterior extension are highlighted.

Eight (8) edentulous patients (2.70%) had the mental foramina exit on top of the alveolar crest.

Discussion

The anterior loop of the mental nerve is commonly described as that part of the neurovascular bundle that transverses anterior and inferior to the mental foramen only to loop back to exit the mental foramen (8-11). While it is often difficult to follow its extend on 2D dental X-rays, it is easier to view these anterior loops on 3D CT images.

When mandibles were dissected, the anterior loop was detected in 60% of 37 cadaver mandibles (12). The length of the loop in this 3D CT study (12) ranged from 0.5 to 5mm. In another study, Neiva et al (13) probed the anterior loop in 22 cadavers, noting that it was present in 88% of the patients and that its mean length was 4.13mm ranging from 1.0 – 11.0mm.

Studies have found CT scans more accurate than traditional 2D dental imaging (14-18) and they should be considered for locating inferior alveolar canals or mental foramina not easily viewed on traditional 2D dental images (periapical films or panoramic images) when considering implant placement, removal of impacted teeth, or treating pathologic lesions.

This 3D Ct cone beam study confirmed, along with other studies, that the alveolar ridge resorbs approximately 6.0-6.5mm when teeth are extracted, which is the average distance noted between the ridge to the anterior extension when compared to root apices to the anterior extension of the canal (1-2).

Using CT scans, Rothman found that the length of the anterior loop could be as long as 10.0mm (19) compared to this study, where it was found the average length for the anterior continuation of the nerve 11.8mm on the left side and 12.0 mm on the right. What is apparent in this study is that the average length of the anterior extension of the canal is greater than in other reported studies. It is unclear if this finding is a function of interpretation or is a result of the accuracy of dental cone beam scanners. What is clear is that these radiographic canals exist, but their clinical importance is a matter of speculation and requires further investigation.

For example, are these radiographic canals filled with nerve and vascular tissues or are they empty? Do they innervate gingival tissues? The answers to these questions are clinically relevant for a host of reasons. When these anterior extensions of the canal are identified on 3D CT images, should they be avoided during dental implant placement? Should increased bleeding be anticipated? Should the patient be informed that there is a chance there will be an altered sensation to the gingiva and adjacent tissues if these canals are penetrated during dental implant surgery? Further investigation will help determine the answers to these questions.

Conclusions

In this 3D dental cone beam CT study, 296 mandibles were studied on dental cone beam scanners. The anterior extension of the IAN was measured relative to length and distance from edentulous ridges or apices of teeth. The clinical ramifications of this anatomic entity were discussed, including the value of 3D imaging when inserting dental implants.

Acknowledgements

Support for this study was generously given by Nobel Biocare AB Gothenberg, Sweden (Grant 2006-492) and Imaging Sciences Inc., Hatfield, PA.


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