Monday, December 2, 2013

Periodontitis & Peri-Implantitis - What's the Difference?

Peri-Implantitis over 5 yrs in smoker. ( Source: Wikipedia)

Replacement of missing teeth with implant supported restorations has become increasingly common. While implant supported restorations do not share the risk of dental caries that natural teeth are subject to, they are susceptible to peri-implant mucositis and peri-implantitis, just as the natural dentition is subject to gingivitis and periodontitis. It is well established that periodic periodontal maintenance can optimize the long-term prognosis of the natural dentition. Like-wise, successful dental implant therapy must include an appropriate recall program. A major etiologic factor in periodontitis is the formation of a biofilm harboring pathogenic bacteria, and this is also true for peri-implantitis. Bacterial colonization of implant abutments has been found to be similar on both zirconia and titanium abutments.
Peri-implantitis is defined as an inflammatory process affecting the tissues around an osseointegrated implant in function, resulting in loss of supporting bone. Peri-implant mucositis is defined as reversible inflammatory changes of the peri-implant soft tissues in the absence of bone loss. The prevalence of peri-implantitis has been reported to be as low as approximately 10% to as high as 47%; the prevalence of peri-implant mucositis is generally greater, ranging from 32% to 80%.
Periodontal and peri-implant bone turnover is a balanced dynamic process that involves resorption and formation, controlled and influenced by the local production of cytokines, with a wide range of inflammatory, hemopoietic, metabolic and immunomodulatory properties. Peri-implant microbial contamination or infection (bacteria and viruses) elicit an immune response regulated by key cytokines (TNF-a, Interleukin [IL]-1ß, TGF- ß, IL-10) that control the progression and/or suppression of the inflammatory response. Over-production of pro-inflammatory cytokines, released by monocytes / macrophages and T cells in response to a microbial challenge can lead to the breakdown of the periodontal or peri-implant tissues.
The continuous balance that exists between the host immune response and potential subgingival pathogens (bacteria / viruses) determines the clinical condition, not only around teeth, but also around osseointegrated dental implants. On February 21st, at the Nowzari Symposium, peri-implantitis will be discussed by Drs. Tord Berglundh and Hessam Nowzari:

Tuesday, November 26, 2013

The Endo Blog Welcomes a New Contributing Author: Hessam Nowzari DDS, PhD

The Endo Blog would like to welcome a new contributing author Dr. Hessam Nowzari.  Dr. Nowzari was the youngest director of the University of Southern California Advanced Periodontics Program (1995-20012).  Dr. Nowzari is a diplomate of the American Board of Periodontology and holds a PhD in Biology and Health Sciences.  Dr. Nowzari is the founder of the Taipei Academy of Reconstructive Dentistry in Taiwan.  In addition to his private practice in Beverly Hills, CA, Dr. Nowzari serves as a scientific expert for the Ministry of Education and Research in Italy. This responsibility includes evaluation of medical products for patient safety and health integrity as well as assessment and ranking of proposed research projects funded by the Italian Ministry of Education and Research.  He is an editor of Aesthetic Periodontal Therapy: Periodontology 2000.  His research in the areas of autogenous bone grafting, orthodontics, guided tissue regeneration & implantology are extensive.  His symposium (www.nowzarisymposium) brings together brilliant scientists and clinicians without the commercial exhibition that ordinarily accompanies current continuing educational courses.  Dr. Nowzari is an educator, scientist, clinician and an strong advocate for scientific integrity in dentistry.

As a periodontist with extensive experience in periodontology and implantology, Dr. Nowzari brings special expertise to The Endo Blog which will contribute to the interdisciplinary discussion we hope to provide our readers and followers.  We are excited to welcome Dr. Nowzari as new contributing author to The Endo Blog.

Thursday, November 21, 2013

The Longevity of Teeth and Oral Implants

A recent systematic review published in the Journal of the American Dental Association by Levin and Halperin-Sternfeld regarding the longevity of teeth and dental implants has raised some interesting, and long overdue questions. This review should have clinicians talking and hopefully talking among dental specialties.

Levin and Halperin-Sternfeld state that the increasing popularity of dental implants may "result in the extraction of teeth that are salvageable, on the basis of convenience rather than as a result of a comparative analysis of prognosis."

Their systematic review was to evaluate the long term survival rates and treatment outcomes for retained compromised teeth in comparison with long term survival rates for dental implants.  Their research question was: "Is the long term survival rate of dental implants comparable to that of natural teeth that are adequately treated and maintained?"

Their review included studies which evaluated long term (15 yrs or more) effectiveness of implants or long term effectiveness of tooth preservation.  Of the 4943 articles identified, 19 met the inclusion criteria.  Special care was taken to evaluate bias, by using the PRISMA guidelines.  Their discussion points out areas where bias may have affected results in any of the studies included in the review.

Some of the points that I found most interesting in the article include:

Periodontally Maintained Teeth
  • Long term tooth survival - Of the several studies which identified the initial periodontal prognosis of teeth, teeth which are periodontally "hopeless" or "questionable" are often most likely to be replaced with implants.  In patients with chronic periodontitis, 20.4% of "questionable" teeth and 34.3% of "hopeless" were lost.  This means that 80% of "questionable" teeth with chronic periodontitis and 66% of "hopeless" teeth with chronic periodontitis, when properly maintained, will survive long term.
  • The overall tooth loss rate and tooth loss rate for compromised teeth were not affected by aggressive disease when the teeth were properly treatment and maintained.

Implant Survival
  • In the studies involving implants, reseachers rarely reported the cause of implant loss.
  • The percentage of implant losses during the follow-up period (minimum 15 yrs) varied between 0 and 33.6%.  The cumulative survival rate ranged between 69.6% and 100%.
  • Bone loss data was also available in several studies ranging between 0.05mm and 2.1mm.
  • Studies with longer follow up periods (up to 23 years) reported an implant loss rate and a marginal bone loss that were almost twice as large as earlier studies - suggesting that greater bone loss and implant loss occur over longer follow up periods. 
  • There was greater variability in the survival of implants placed into grafted sinuses, suggesting the sinus graft may decrease the survival rate of dental implants.
  • Since implants are exposed to the same pathogens as teeth, while implants cannot decay, they are susceptible to peri-implantitis.  They concluded that one in five implants will result in peri-implant disease.
  • Peri-implant disease currently has no standard treatment.
  • Levin and Halperin-Sternfeld concluded "We found that, overall, studies dealing with dental implants tended to present a higher risk of bias. An important issue to consider regarding implant survival is the industry-derived financial support for studies of dental implants. Anecdotal evidence suggests that many of the studies in which investigators report on implant success are supported directly or indirectly by the dental implant industry; however, this information is not always disclosed in the articles. Clinicians should keep this in mind when evaluating these materials."
  • There is still a lack of consensus regarding what constitutes a "successful implant"  This criteria varies amount different studies and different implant systems.
Levin and Halperin-Sternfeld also discussed the difficulty of comparing tooth and implant survival. For example, tooth survival studies take an epidemiological approach, while implant studies typically use a distinct or ideal-type of patient.  Dental implant systems are constantly changing and many earlier systems are no longer used.  Researchers have studied the rate of tooth loss for much longer than they have studied the rate of implant loss.  Levin and Halperin-Sternfeld stated, "When assessing the general loss rate of teeth and implants over follow-up periods of at least 15 years, we found a range of 3.6 to 13.4 percent for tooth loss and a range of 0 to 33 percent for implant loss.  This may imply a generally higher rate of implant loss than tooth loss."  A final point of their discussion is that "dental implants are not the reference standard for replacing compromised teeth because they will not survive forever".

Levin and Halperin-Sternfeld made several important points regarding dental implants that are often left out of the treatment planning discussion/informed consent regarding dental implants.  They concluded that, "…the decision to retain properly treated and maintained teeth for as long as possible seems to provide an overall solution that can reduce the treatment risks over the long term".

Further Discussion

A recent survey by Azarpazhooh et. al. demonstrated a declining pattern of preference for root canal therapy (RCT) in favor of implant supported crowns (ISC) among general dentists, periodontists, prosthodontists and oral surgeons as opposed to endodontists.  This declining pattern showed a significantly higher preference for ISC over RCT retreatment.

Implants LOOK and FEEL like natural teeth when
they are next to a natural teeth.
Given the historical success of endodontic therapy, what would cause this trend?

Effective marketing by implant manufacturers has gone a long way to convince the public and some dental practicioners that implants are just like teeth.  Some even promote them as superior, when in reality they are very different and should not be compared as alternative treatments.

We recognize that industry is behind most of the innovation that we see in dentistry today.  However, when these same companies are also the financial backers for the research done to evaluate these products there is a serious conflict of interest.  When universities and clinicians are financially supported by these same companies, they forfeit their impartiality and ability to give an objective opinion.  When implant companies or their clinician representatives are the main source of implant continuing education, we may begin to understand how a preference towards more aggressive implant placement is developing.

As clinicians, we have the responsibility to understand the research, interpret the bias, see through the sales pitch and provide our patients with the best treatment options and maintain our fiduciary/ethical relationship at the same time.  This review by Levin and Halperin-Sternfeld makes a bold statement in support of Holm-Pedersen and colleagues' conclusions "that implant survival will not surpass tooth survival over the long term." This is very different from what we hear from the implant manufacturers and their marketing teams.

To read the abstract or access the full article: click here

I look forward to your comments. This article is meant to begin a discussion.

If you don't want to share them here, then forward this article to a colleague and have a discussion with them.


1. Levin, L., Halperin-Sternfeld, M. "Tooth Preservation or Implant Placement - A systematic review of long-term tooth and implant survival rates" 2013 JADA 144:10, 1119-1133.

2. Azarpazhooh, A. Dao, T., Figueiredo, R., Krahn, M., Friedman, S.,  "A Survey of Dentist' Preferences for the Treatment of Teeth with Apical Periodontitis" 2013 JOE 39:10, 1226-1233.

3. Holm-Pedersen P., Lang, N.P., Muller, F. "What are the Longevities of Teeth and Oral Implants" 2007 Clin Oral Implants Res 18(suppl 3):15-19.

Thursday, November 14, 2013

10 Yr Success of Apicoectomy & RCT Retreatment

Endodontic Surgery and RCT Retreatment can preserve the natural tooth and the periodontium.

Apicoectomy on #10 was re-done using MTA as a retrofill and retreatment of short RCT on #11 in 2003.  10 yr recall finds both #10 and #11 are fully functional, asymptomatic & with complete radiographic healing.

Monday, October 21, 2013

Odontogenic Rhinosinusitis - An Introduction

Recently, an article in the Journal of Otolaryngology, Head and Neck Surgery, extrapolated data from a County hospital in Minnesota and calculated a national cost of inpatient hospital care for odontogenic deep neck space infections to be $200 million annually (1).  Absent from this article was any mention of the cost or incidence of odontogenic rhinosinusitis.  The reported incidence in the literature of dental pathology as a cause of rhinosinusitis is 10-12% (2).  The primary source data for this incidence is from the 1950s and there is no documentation in the referenced articles of the data used to calculate this incidence.  Therefore, the true incidence odontogenic rhinosinusitis is unknown and, based on my experience, most likely underappreciated. 

By BruceBlaus (Own work) via Wikimedia Commons
Prior to reviewing odontogenic rhinosinusitis, we need to discuss common definitions.  Rhinosinusitis is inflammation of the paranasal sinus and/or nasal cavities.  This inflammation may be caused by allergic, infectious or immunogenic etiologies.  Acute rhinosinusitis lasts up to 4 weeks, subacute rhinosinusitis lasts up to 12 weeks, and chronic rhinosinusitis lasts greater than 12 weeks.  Acute rhinosinusitis is a clinical diagnosis based on the history and physical exam.  Symptoms of sinusitis have been divided among major and minor factors (3).  The diagnosis requires either two major factors or one major factor and 2 minor factors.  Major factors include facial pain, facial congestion, nasal obstruction (blockage), purulent (discolored) nasal drainage (anterior or posterior), lack of or absence of smell, or fever.  Minor symptoms include headache, fatigue, halitosis (bad breath), and dental pain, cough or ear pressure or pain.

Major Symptoms
Minor Symptoms
Facial Pain
Facial Congestion
Nasal Obstruction
Purlent Drainage
Dental Pain
Loss of Smell
Ear Pressure/Pain

Odontogenic rhinosinusitis is defined as sinusitis induced by a dental lesion.  The common etiologies include periapical and periodontal disease, odontogenic lesions and iatrogenic and traumatic causes.  Iatrogenic causes include complications of tooth extractions, implants, sinus augmentation, osteotomies and other orthodontic surgery, and a foreign body reaction to either the root canal sealant or filling material used in root canal therapy.  A significant amount of literature is dedicated to complications associated with dental implants and sinus lifts.  The reported incidence of rhinosinusitis resulting from sinus augmentation is 0-27% (4).  However, when strict criteria are used to define rhinosinusitis, the incidence is 4.5%.  Approximately 1/3 of these patients will progress from acute to chronic rhinosinusitis.  Chronic rhinosinusitis requiring surgical intervention from sinus augmentation is reported to be 1.3% of patients(4).  Sinus inflammation consisting of mucous membrane thickening on preaugmentation CT imaging is a statistically significant risk factor for post procedure acute or chronic rhinosinusitis (5). These are patients who would benefit from a preaugmentation ENT evaluation.

Treatment of sinusitis consists of saline irrigations, topical and systemic decongestants, antibiotics, topical and systemic steroids and allergy treatment.  Antibiotics are used to treat acute rhinosinusitis and acute exacerbations of chronic rhinosinusitis.  The specific antibiotic used is based on common microbiology patterns or the result of endoscopically-guided cultures.  Recommended first-line antibiotics include Augmentin, high-dose amoxicillin, and extended spectrum cephalosporins.  Surgery for acute or chronic rhinosinusitis is usually a last resort after maximal medical therapy has failed.

Odontogenic rhinosinusitis presents a unique challenge to the otolaryngologist.  The diagnosis is frequently delayed.  A dental source for the sinus infection is frequently not considered until after both medical and surgical therapy has failed to resolve the patient's symptoms and radiographic disease.  A primary cause for the delay in diagnosis is the failure of the radiologist and ENT physician to adequately assess dental pathology on CT imaging.  In a 2010 retrospective case series involving 21 patients with known odontogenic rhinosinusitis, the initial radiology report failed to mention radiographic findings of dental pathology in 14 or 67% percent of the patients (6).  There are symptoms which suggest an odontogenic source for the infection in patient presenting with rhinosinusitis.  First, the large majority of patients will present with unilateral symptoms.  This means that the patient will complain of nasal discharge, cheek pain, dental pain or nasal obstruction primarily on one side.  Another unique symptom to odontogenic rhinosinusitis is a foul smell noted by the patient.  In 76 patients with known odontogenic rhinosinusitis, 33 or 43% reported a foul smell (6,7,8).

In addition to early diagnosis, a successful outcome of odontogenic rhinosinusitis requires appropriate antibiotic therapy based on the common microbiology findings of a mixed polymicrobial infection.  Like other odontogenic-induced infections, first-line antibiotic coverage for ORS is clindamycin.  Additionally, successful treatment depends on eliminating the source of the infection.  This requires early involvement of the dental health professional.  In general, dental procedures take precedence over the ENT procedures.  Situations where ENT surgery would precede dental surgery include the following:

1. A complications of rhinosinusitis requiring emergent surgery.

2. Sinus surgery in an infected maxillary sinus performed prior to closure of an oral antral fistula to increase the chance of success.

3. Sinus surgery for pre-existing sinus disease prior to sinus augmentation (9).

The most important aspect of successful treatment consists of good coordination of care and communication between the dentist and ENT physician.

Case 1

A 51 year old female presents with one year of left facial & tooth pain, left nasal obstruction, postnasal drainage and headaches.  Past dental history is significant for RCT of teeth 10 & 11, apicoectomy of tooth #10, and dental implants #12 & 13.  The implants failed and she developed an oral antral fistula after removal of the implants and debridement of necrotic bone. Coronal CT image demonstrating severe left maxillary and ethmoid sinus disease. This one sided sinus disease was of odontogenic origin.

A coronal CT 2 months after ethmoid and maxillary sinus surgery showing complete resolution of sinus disease. 

Several months later, she underwent a successful sinus lift with implantation and a coronal CT image demonstrating ossification of the sinus augmentation.

Case 2

A 70 year old male with postnasal drainage presents with a right nasal cavity mass demonstrated on nasal endoscopy. 

A yellow discharge is associated with the object.  A coronal CT image demonstrates extrusion of a dental implant 9.5mm into the right nasal cavity. 

Additional implants extruding into the maxillary sinuses without radiographic disease.


Case 3

A 69 year old female presents with 12 months of brown-yellow nasal drainage, mild right facial pressure, right nasal congestion and a foul taste and smell.  She presented to her general dentist 3 months prior to her ENT consultation with a right gingival buccal lesion that resolved with clindamycin. A coronal CT image of the paranasal sinuses demonstrates maxillary and ethmoid sinusitis ipsilateral to right maxillary periapical tooth disease with buccal plate and maxillary sinus floor boney erosion.  
A sagittal image through the right maxillary sinus shows periapical disease of teeth #2 and 3.  This is another odontogenic sinusitis requiring dental treatment as the initial treatment for her sinus problem.   

Posted by: Tim Haegen MD of the Arizona Sinus Center


1.  Morbidity and cost of odontogenic infections.  Eisler L, Wearda K, Romatoski K, Odland RM.  Otolaryngol Head Neck Surg. 2013 Jul;149(1):84-8.

2.  Clinical aspects of odontogenic maxillary sinusitis: a case series.  Longhini AB. Ferguson BJ.  International Forum of Allergy & Rhinology. 1(5):409-15, 2011 Sep-Oct. 

3.  Lanza DC, Kennedy DW. Adult rhinosinusitis defined. Otolaryngol Head Neck Surg 1997;117:S1-7.

4.  ENT assessment in the integrated management of candidate for (maxillary) sinus lift. Pignataro L, Mantovani M, Torretta S, et al.  ActaOto rhino laryngolItal 28:110–119, 2008.

5.  Late signs and symptoms of maxillary sinusitis after sinus augmentation. Manor Y, Mardinger O, Bietlitum I, et al.OralSurg Oral Med Oral Pathol Oral RadiolEndod 110:e1–e4, 2010.

6.  Clinical aspects of odontogenic maxillary sinusitis: a case series.  Longhini AB. Ferguson BJ.  International Forum of Allergy & Rhinology. 1(5):409-15, 2011 Sep-Oct.  

7.  Microbiology of acute and chronic maxillary sinusitis associated with an odontogenic origin. Brook I. Laryngoscope. 115(5):823--‐5, 2005 May.

8.  Late signs and symptoms of maxillary Sinusitis after Sinus augmentation. Manor Y, Mardinger O, Bietlitum I, et al. Oral Surg Oral Med Oral Pathol Oral RadiolEndod 110:e1-e4, 2010.

9.  The characteristics and new treatment paradigm of dental implant-related chronic rhinosinusitis.  Chen YW, Huang CC, Chang PH, Chen CW, Wu CC, Fu CH, Lee TJ.  Am J Rhinol Allergy. 2013 May;27(3):237-44.