Forth Molar?

Did you all know that some people even have more than their 3rd molar.  Although uncommon, we do come across these types of cases where patients have extra teeth, a.k.a. “supernumerary”.  In a recent study in the Journal of Oral & Maxillofacial Surgery, Dr. Shahzad and his team studied the prevalence of forth molars and found it to be 2%.  More common in black patients and typically in the upper jaw and only on one side.   The decision to whether to remove them is based on the same risks/benefits ratio as the removal of their molars.

So why are third molars such an issue?  There was a literature review done in 2007 looking at all the date on Ovid Medline, PubMed, Google Scholar, and the Cochrane.  This was later published as the “white paper”.

The following is a brief summary of some of the findings related to third molars:

  •  The presence of visible third molars is associated with overall elevated levels of periodontitis (gum disease) and that of immediately adjacent teeth (second molars). 
  •  In the presence of visible third molars, periodontitis involving adjacent teeth is progressive and only partially responsive to therapy (typically deep cleanings and antibiotics). 
  • The presence of pocket depths of ≥4-5 mm and/or bleeding on probing should be recognized as possible predictors of future progression of periodontitis (gum disease). 
  • Periodontal disease as indicated by probing depths 4 mm exists in and around asymptomatic third molars
  • GTR and/or DBP (bone grafting after extraction) may be beneficial in instances where there is evidence of significant pre-existing attachment loss (bone loss on the back side of the second molar). 
  • Absence of symptoms does not indicate absence of disease or pathology.
  • Periodontal disease progresses even in the absence of symptoms. 
  • Periodontal defects, as assessed by pocket depths, deteriorate with increasing age in the presence of retained third molars. 
  • Caries (cavities) in erupted third molars increases in prevalence with increasing age. 
  • The incidence of postoperative morbidity following third molar removal is higher in patients > 25 years. 
  • Germectomy (removal of the third molar that is premature and has one third or less of root formation) may be associated with a lower incidence of postoperative morbidity. 
This is why it is recommended to only remove the third molars, if they are impacted and causing gum disease and damage to the adjacent teeth and soft-tissue.  This evaluation should take place at a younger age, which includes taking an X-ray (panorex) to evaluate the position of the third molars versus the adjacent teeth and the presence of gum disease and bone loss.  The best time to remove the problematic third molars is when they are still premature and the roots are not fully developed, some as young as 12-13 years old.  This reduces post-operative morbidity, facial swelling, pain and so on.  Younger patients typically heal faster and have less complications.
For a complete list of all the findings please search for the actual paper online by searching “White paper of third molars”.