with impacted teeth from 390 patients. The most common diagnosis was dentigerous cyst (56.5% of lesions; n = 230), followed by odontogenic keratocyst (6.1%) and then paradental cyst (5.7%; n = 23).
It is interesting that these figures contrast starkly with data from other studies that have shown that paradental cysts are exceedingly rare or are not diagnosed at all. Six of the studies shown in Table 4.1 did not record any inflammatory collateral cysts. Costa et al. (2014 ) also reviewed 11 studies that reported histological findings associated with third molars in 8464 patients. The most common finding was of normal dental follicle (76%), but the most common lesions were dentigerous cysts, found in 410 cases (11%). Only one paper (Al‐Khateeb and Bataineb 2006 ) reported finding any paradental cysts and there were only 2, suggesting an overall prevalence of 0.05%. In a systematic review of the prevalence of odontogenic cysts and tumours associated with impacted third molars, Mello et al. (2019 ) reviewed 16 studies reporting histological diagnoses associated with more than 50 000 teeth. There were 1371 cysts, of which 783 (57.1%) were dentigerous cysts, 400 (29.2%) radicular cysts, and 150 (10.9%) odontogenic keratocysts. These authors also found the same single study (Al‐Khateeb and Bataineb 2006 ) that had reported only 2 paradental cysts. These data are similar to other studies that have examined tissues associated with impacted third molars and have not reported a single paradental cyst (e.g. Curran et al. 2002 [USA]; Stathopoulos et al. 2011 [Greece]; Patil et al. 2014 [India]).
Table 4.2 Paradental cysts. Age, sex, and site distribution from selected reports, and from the review of 222 cases by Philipsen et al. (2004 ).
| References | n | Mean agea | Age range | Male (%) | % Bilateral |
|---|---|---|---|---|---|
| Craig (1976 ) | 48 | 3rd decade | NR | 83.0 | 2.1 |
| Ackermann et al. (1987 ) | 50 | 3rd decade | 17–62 | 70.0 | 6.0 |
| Vedtofte and Praetorius (1989 ) | 15 | 24.4 | 18–34 | 60.0 | 0.0 |
| de Sousa et al. (2001 ) | 54b | 3rd decade | 13–47 | 39.0 | NR |
| Colgan et al. (2002 ) | 15 | 27.4 | 18–43 | 46.6 | 6.6 |
| Jones et al. (2006 ) | 376 | 29.6 | 17–74 | 57.3 | NR |
| Philipsen et al. (2004 ) | 11 | 29.9 | 18–46 | 63.6 | 18.0 |
| Tamiolakis et al. (2019 ) | 53 | 29.3 | 18–56 | 52.8 | NR |
| Mohammed et al. (2019 ) | 23 | 30.2 | 11–51 | 69.5 | NR |
| Philipsen et al. (2004 ) | 222c | 27.6 | 18–47 | 70.6 | 4.1 |
n, number of patients; NR, not reported.
a In some reports, the mean age is not given, so the peak decade is included.
b Includes three cases on first or second molars.
c Total cases reviewed, n for each parameter varies.
Table 4.3 Mandibular buccal bifurcation cysts. Age, sex, and site distribution from selected reports, and from the review of 110 cases by Philipsen et al. (2004 ) (see text for discussion).
| References | First molars | Second molars | |||||||
|---|---|---|---|---|---|---|---|---|---|
| n | % Male | % Bilateral | n | Mean age | Age range | n | Mean age | Age range | |
| Vedtofte and Praetorius (1989 ) | 12 | 33.3 | 16.6 | 5 | 8.0 | 7–9 | 7 | 13.3 | 11–15 |
| Wolf and Hietanen (1990 ) | 6 | 16.6 | NR | 3 | 7.3 | 6–9 | 3 | 13.0 | 12–14 |
| Thurnwald et al. (1994 ) | 10 | 70.0 | 40.0 | 10 | 7.7 | 5–9 | – | – | – |
| Pompura et al. (1997 ) | 32 | 43.7 | 37.5 | 32 | 7.5 | 5–11 | – | – | – |
| Philipsen et al. (2004 ) | 110a | 55.2 | 23.9 | 36 | 8.7 |
|